• Title/Summary/Keyword: Non-Invasive

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Growth, Photosynthesis and Chlorophyll Fluorescence of Chinese Cabbage in Response to High Temperature (고온 스트레스에 대한 배추의 생장과 광합성 및 엽록소형광 반응)

  • Oh, Soonja;Moon, Kyung Hwan;Son, In-Chang;Song, Eun Young;Moon, Young Eel;Koh, Seok Chan
    • Horticultural Science & Technology
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    • v.32 no.3
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    • pp.318-329
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    • 2014
  • In order to gain insight into the physiological responses of plants to high temperature stress, the effects of temperature on Chinese cabbage (Brassica campestris subsp. napus var. pekinensis cv. Detong) were investigated through analyses of photosynthesis and chlorophyll fluorescence under 3 different temperatures in the temperature gradient tunnel. Growth (leaf length and number of leaves) during the rosette stage was greater at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures than at ambient temperature. Photosynthetic $CO_2$ fixation rates of Chinese cabbage grown under the different temperatures did not differ significantly. However, dark respiration rate was significantly higher in the cabbage that developed under ambient temperature relative to elevated temperature. Furthermore, elevated growth temperature increased transpiration rate and stomatal conductance resulting in an overall decrease of water use efficiency. The chlorophyll a fluorescence transient was also considerably affected by high temperature stress; the fluorescence yield $F_J$, $F_I$, and $F_P$ decreased considerably at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures, with induction of $F_K$ and decrease of $F_V/F_O$. The values of RC/CS, ABS/CS, TRo/CS, and ETo/CS decreased considerably, while DIo/CS increased with increased growth temperature. The symptoms of soft-rot disease were observed in the inner part of the cabbage heads after 7, 9, and/or 10 weeks of cultivation at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures, but not in the cabbage heads growing at ambient temperature. These results show that Chinese cabbage could be negatively affected by high temperature under a future climate change scenario. Therefore, to maintain the high productivity and quality of Chinese cabbage, it may be necessary to develop new high temperature tolerant cultivars or to markedly improve cropping systems. In addition, it would be possible to use the non-invasive fluorescence parameters $F_O$, $F_V/F_M$, and $F_V/F_O$, as well as $F_K$, $M_O$, $S_M$, RC/CS, ETo/CS, $PI_{abs}$, and $SFI_{abs}$ (which were selected in this study), to quantitatively determine the physiological status of plants in response to high temperature stresses.

Comparison of 99mTc-Tin colloid colloid and 99mTc-DISIDA Hepatoscintigraphy in Miniature Pigs (미니돼지에서 99mTc-Tin colloid와 99mTc-DISIDA를 사용한 간신티그라피의 비교 연구)

  • Shim, Kyung-Mi;Kim, Se-Eun;Lee, Won-Guk;Koong, Sung-Soo;Bae, Chun-Sik;Lee, Jae-Yeong;Choi, Seok-Hwa;Han, Ho-Jae;Kang, Seong-Soo;Park, Soo-Hyun
    • Journal of Life Science
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    • v.16 no.6
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    • pp.1060-1065
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    • 2006
  • Non-invasive evaluation of liver function in animal models remains a challenge. Hepatoscintigraphy provides information about changes in liver size and shape, and enables to understand general liver function. Futhermore it is readily used to diagnosis complications of liver transplantation like hepatitis, rejections and biliary complications. In this study, we investigated the usefulness of evaluating the liver function in miniature pigs with $^{99m}Tc-Tin$ colloid and $^{99m}Tc-DISIDA$ which are the most commonly used radiopharmaceuticals in human medicine. In result, $^{99m}Tc-Tin$ colloid was uptaked in lung, liver, gastric wall and kidney in miniature pigs. And $^{99m}Tc-DISIDA$ showed continuous uptake images of heart, lung, liver, gallbladder and duodenum, and it was similar to human's. Therefore we could conclude $^{99m}Tc-Tin$ colloid would not be suitable for evaluating hepatic function because of it's nonspecific affinity, however $^{99m}Tc-DISIDA$ scintigraphy would be an effective method for detecting hepatobiliary function in miniature pigs.

STUDY ON MUTATION OF P53 AND EXPRESSION OF MDM-2 IN DMBA INDUCED CARCINOMA OF HAMSTER BUCCAL POUCH (DMBA로 유도된 햄스터 협낭암종에서 p53 유전자 변이와 mdm-2 단백의 발현에 관한 연구)

  • Park, Yong-Sun;Kim, Kyung-Wook;Lee, Jae-Hoon;Kim, Chang-Jin
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.27 no.5
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    • pp.373-384
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    • 2001
  • Cellular proliferation is an intricately regulated process mediated by the coordinated interactions of critical growth control genes. Two of these factors in mammalian cells are the p53 and mdm-2 genes. A protein product of the mem-2 oncogene has been recently shown to associate with the protein encoded by the tumor suppressor gene p53. The p53 tumor suppressor protein is stabilized in response to DNA damage and other stress signals and causes the cell to undergo growth arrest or apoptosis, thus preventing the establishment of mutations in future cellular generations. Mutation or loss of p53 is a very common event in tumor progression. It occurs in about 50% of all tumors analysed including of colon, lung, breast and liver. The cellular mdm-2 gene, which has potential transforming activity that can be activated by overexpression, is amplified in a significant percentage of human sarcoma and in other mammalian tumors. Proteins encoded by the mdm-2 gene are able to bind to the p53 protein and, when overexpressed, can inhibit p53's transcriptional activation function, thus mdm-2 can act as a negative regulator of p53 function. Experimental study was performed to observe the relationship between p53 gene mutation and mdm-2 protein expression and apply the results to the clinical activity. 36 golden syrian hamster each weighing $60{\sim}80g$ were used and painted with 0.5% DMBA by 3 times weekly on the right buccal cheek(experimental side) for 6, 8, 10, 12, 14 and 16 weeks. Left buccal cheek(control side) was treated with mineral oil as the same manner to the right side. The hamsters were sacrificed on the 6, 8, 10, 12, 14 & 16 weeks. Normal and tumor tissues from paraffin block were examined for histology and immunohistochemistry observation, and were completely dissected by microdissection and DNA from both tissue were isolated by proteins K/phenol/chloroform extraction. Segments of the hamster p53 exons 5, 6, 7 and 8 were amplified by PCR using the oligonucleotide primers, and then confirmational change was observed by SSCP respectively. The results were as follows : 1. Dysplasia at 6 weeks, carcinoma in situ at 8 weeks and invasive carcinoma from 10 weeks could be observed in experimental groups. 2. p53 mutations were detected in 10 of the 36(28%) and the exons 6(6 of the 10 : 60%) was the most hot spot area among the highy conserved region(exons 5, 6, 7 & 8). 3. Immunohistochemical study confirmed 22 of the 36(61%) of p53 expression involving 10 of p53 mutations. 4. mdm-2 expression of was showed in 3 of the 36(8%) involving 1 of the 22 of p53 expression and 2 of the 14 of p53 non-expression. From the above results, mutation of p53 gene or expression of p53 protein may have the influence of the DMBA induced carcinoma of hamster buccal pouch but the expression of mdm-2 protein may not have relationship with tumorigenesis.

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A new diagnostic method for diabetic neuropathy using $TcpO_2$ ($TcpO_2$ 이용한 당뇨병성 신경병증 환자의 조기진단)

  • Hong, Hyun-Ki;Kim, Sung-Woo;Nam, Ki-Chang;Cha, Eun-Jong;Kim, Deok-Won
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.44 no.3
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    • pp.1-8
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    • 2007
  • PDiabetic neuropathy is one of the most common diabetes related complications including diabetic nephropathy and retinopahty. In clinical practices, nerve conduction velocity (NCV) has been used as a standard method for diagnosing diabetic neuropathy. However, it applies maximum current of 100mA to nerves causing stress and pain to patients. In this study, as a non-invasive method, $TcpO_2$ was utilized to investigate the difference and relationship between $TcpO_2$ and $SpO_2$ of normal and diabetic neuropathy subjects. In addition, a new method of diagnosing diabetic neuropathy using $TcpO_2$ is suggested. 50 normal subjects and 50 diabetic patients with neuropathy diagnosed by NCV participated in this study. Parameters used in this study were $TcpO_2$, $TcpCO_2$, and $SpO_2$. As a result of the $TcpO_2$ measurements, statistical significances were found from $TcpO_2$ of hands and feet from normal and patients group(p<0.01). $SpO_2$ measured from index finger of normal and patient groups showed no statistical significance(p>0.05). On the other hand, $SpO_2$ measured from great toes of normal and patient groups showed statistical significance(p<0.01). Correlation coefficient between $SpO_2$ of finger and $TcpO_2$ of hand was 0.400 (p<0.01) and $SpO_2$ of toe and $TcpO_2$ of foot was 0.471(p<0.01). Both correlation values were statistically significant. Sensitivities and specificities of the $TcpO_2$ method were found to be 66 % and 92 %, respectively. If the suggested $TcpO_2$ method is used periodically, prevention and early diagnosis of diabetic neuropathy would be possible.

Appling Nursing Theory to Clinical Practice of Home Health Care (가정간호실무에 적용가능한 이론적틀)

  • Woo, Seon-Hye
    • Journal of Home Health Care Nursing
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    • v.11 no.1
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    • pp.5-13
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    • 2004
  • The home health care industry has grown rapidly and can be expected to continue to grow in the foreseeable future. Home health care refers to the practice of nursing applied to clients with a health condition in the clients place of residence. clients and their designated care givers are the focus at home health nursing practice. The goal of care is to initiate. manage and evaluate the resources needed to promote the clients optimal level of well-being and function. Nursing activities necessary to achieve this goal may warrant preventive maintenance and restorative emphases to prevent potential problems from developing. Many project program were suggested home health care model for Korea's health care system and policy direction for expansion and establishment of home health care .But the aim of this paper is to provide on overview for theoretical frame work in home health care. Theories and conceptual frameworks or models are important nursing because they define and guide the boundaries of professional practice and identify key nurse-patient-caregiver relationships that emerge with caring. Following is the research with an investigation of the literature review in the University of Arizona international medline database, In conclusion, are as followers: First, many nursing theorists have had a tremendous impact on nursing practice. the following highlights those nursing theorists that are particularly helpful in understanding home health care. 1. Florence Nightingale : Our earliest theoretical legacy. Nightingale's believes are reflected in basic infection control practice such as hand washing and infectious waste disposal and are key nursing interventions in home care. 2. Martha Roger's :Science of unitary human beings theory. Rorger's believed that the focus of shared. non invasive healing modelities is the human environmental field rather than direct physical care. These modelities continue to evolve as our awareness (reflecting greater diversity, faster rhythms, motions, and ways of knowing) transcends time and space, allowing individuals to get in touch with their integral nature of unbroken wholeness. On people as ever changing energy fields have special relevance in home care especially with hospice and palliative care applications. 3. Madeline Leininger's; Transcultural nursing theory. Home care nurses move through a variety of communities and often care for patients from different cultural back grounds. Therefore Leininger's work has a good that with home care because home care nursing practice is very culturally focused. 4. Dorothea Orem's : Self care deficit theory. Orem's theory views care as something to be performed by both nurses and patients. The role of the nurse is to provide education and support that help patients acquire the necessary activities to perform self-care. Orem's theory is foundational to have care because it begins to truly acknowledge the role of the patient in managing his or her own health. which is referred to as self-care. 5. Margaret Neuman's; Health as expending consciousness theory. Neuman believes that health compasses disease and reflects an underlying pattern of person-environment interaction. A key application of 'Neuman's work to home care is for nurses to understand that health and illness do not necessarily exist at opposite ends of a continuum. 6. Jean Watson's: Theory of human caring. Watson's theory of human caring in nursing proposes human caring as the moral ideal of nursing. Nurses participate human caring to protect, enhance and preserve humanity by assisting individuals to fing meaning in illness. pain and existence and to help others gain self knowledge. self control. and self healing such thinking lends richness to theory development. as well as clinical practice in home care. Second, Robin Rice : Dynamic self determination for self care. (A theoretical framework for home care) Dynamical self determination for self care can be useful to home care nurses in a variety of ways. As research tool it can be reflected in the interview process when the home visit. The home care nurse's role is that of facilitator of patient self-determination for self care through numerous strategies. including patient education and case management.

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Airway Responses to Bronchoprovocation Using High-Resolution Computed Tomography in Patients with Bronchial Asthma (기관지천식환자에 있어서 고해상도 전산화단층촬영술을 이용한 기관지유발에 대한 기도의 반응)

  • Choi, Byoung-Whui;Kang, Yoon-Jeong;Ko, Hyung-Ki;Park, In-Won;Hue, Sung-Ho;Kim, Yang-Soo;Kim, Young-Goo;Kim, Kun-Sang;Kim, Jong-Hyo
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.6
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    • pp.813-822
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    • 1995
  • Background: Bronchial hyperresponsiveness and abnormal response such as a loss of distensibility are pathophysiologic characteristics if bronchial asthma. The only means of direct in vivo measurement of airway size had been a tantalium bronchography, until high-resolution computed tomography(HRCT) enabled to measure noninvasively two dimensional airway area more accurately and reliably. Method: To investigate airway area responses to bronchial provocation with methacholine and evaluate the major sites of bronchial constriction in patients with bronchial asthma. We examined HRCT scans in five patients with bronchial asthma who had significant bronchoconstriction(20% or more decrease in $FEV_1$) using CT scanner(5,000T CT, Shimadzu Co, Japan) before and in 3~5 min. after methacholine inhalation. Airways which were matched by parenchymal anatomic landmarks in each patient before and after methacholine inhalation were measured using film scanner(TZ-3X scanner; Truvel Co. Chatsworth CA, USA) and a semiautomated region growing method. Results: 1) We identified 9 to 12 airways in each patient which were matched by parenchymal anatomic landmarks before and after methacholine inhalation. 2) Airway responses to methacholine are quite different even in a patient. 3) The constriction of small airways(average diameter <2 mm; area < $3.14mm^2$) was 48.7%(8.3; SEM, n=43), being more prominant than that of large airways(average diameter >2 mm; area > $3.14mm^2$), 53.8% (4.4;SEM, n=10), but not significantly different(p>0.05). 4) There was no significant difference in the degree of constriction between upper(44.3% +5.8; mean + SEM, n=30) and lower lung regions(56.7% +4.5, n=23). Conclusions: Thus airway responses to methacholine bronchoprovocation is quite variable in a patient with bronchial asthma and has no typical pattern in patients with bronchial asthma.

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Radiographic change of grafted sinus floor after maxillary sinus floor elevation and placement of dental implant (상악동저 거상술과 임플란트 식립 후 상악동저 변화에 대한 연구)

  • Cho, Sang-Ho;Kim, Ok-Su
    • Journal of Periodontal and Implant Science
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    • v.36 no.2
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    • pp.345-359
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    • 2006
  • Loss of maxillary molar teeth leads to rapid loss of crestal bone and inferior expansion of the maxillary sinus floor (secondary pneumatization). Rehabilitation of the site with osseointegrated dental implants often represents a clinical challenge because of the insufficient bone volume resulted from this phenomenon. Boyne & James proposed the classic procedure for maxillary sinus floor elevation entails preparation of a trap door including the Schneiderian membrane in the lateral sinus wall. Summers proposed another non-invasive method using a set of osteotome and the osteotome sinus floor elevation (OSFE) was proposed for implant sites with at least 5-6mm of bone between the alveolar crest and the maxillary sinus floor. The change of grafted material in maxillary sinus is important for implant survival and the evaluation of graft height after maxillary sinus floor elevation is composed of histologic evaluation and radiomorphometric evaluation. The aim of the present study was radiographically evaluate the graft height change after maxillary sinus floor elevation and the influence of the graft material type in height change and the bone remodeling of grafts in sinus. A total of 59 patients (28 in lateral approach and 31 in crestal approach) who underwent maxillary sinus floor elevation composed of lateral approach and crestal approach were radiographically followed for up to about 48 months. Change in sinusgraft height were calculated with respect to implant length (IL) and grafted sinus height(BL). It was evaluated the change of the graft height according to time, the influence of the approach technique (staged approach and simultaneous approach) in lateral approach to change of the graft height, and the influence of the type of graft materials to change of the graft height. Patients were divided into three class based on the height of the grafted sinus floor relative to the implant apex and evaluated the proportion change of that class (Class I, in which the grafted sinus floor was above the implant apex; Class II, in which the implant apex was level with the grafted sinus floor; and Class III, in which the grafted sinus floor was below the implant apex). And it was evaluated th bone remodeling in sinus during 12 months using SGRl(by $Br\ddot{a}gger$ et al). The result was like that; Sinus graft height decreased significantly in both lateral approach and crestal approach in first 12 months (p$MBCP^{TM}$ had minimum height loss. Class III and Class II was increased by time in both lateral and crestal approach and Class I was decreased by time. SGRI was increased statistically significantly from baseline to 3 months and 3 months(p<0.05) to 12 months(p$ICB^{(R)}$ single use, more reduction of sinusgraft height was appeared. Therefore we speculated that the mixture of graft materials is preferable as a reduction of graft materials. Increasing of the SGRI as time goes by explains the stability of implant, but additional histologic or computed tomographic study will be needed for accurate conclusion. From the radiographic evaluation, we come to know that placement of dental implant with sinus floor elevation is an effective procedure in atrophic maxillary reconstruction.

$^{99m}Tc$-Tetrofosmin Scintimammography in Suspected Breast Cancer Patients: Comparison with $^{99m}Tc$-MIBI (유방암이 의심되는 환자에서 $^{99m}Tc$-Tetrofosmin을 이용한 유방스캔: $^{99m}Tc$-MIBI와 비교)

  • Kim, Seong-Jang;Kim, In-Ju;Kim, Yong-Ki;Bae, Young-Tae
    • The Korean Journal of Nuclear Medicine
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    • v.34 no.2
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    • pp.119-128
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    • 2000
  • Purpose: The aim of this study was to investigate the diagnostic role of $^{99m}Tc$-Tetrofosmin in detection of breast cancer and compared with that of $^{99m}Tc$-MIBI. Material and Methods: Forty-eight patients with a clinically palpable mass or abnormal mammographic or ultrasonographic findings had $^{99m}Tc-MIBI\;and\;^{99m}Tc$-Tetrofosmin scintimammographies after intravenous injection of 925 MBq of radiopharmaceuticals. The scintimammographs were correlated with histopathologic findings. Results: Thirty-three patients were diagnosed with breast cancer and 15 patients with benign breast diseases. The numbers of true positive, true negative, false positive, and false negative cases of $^{99m}Tc$-MIBI scintimammography were 29, 10, 5, and 4 respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of $^{99m}Tc$-MIBI scintimammographies were 87.8%, 66.7%, 85.3%, and 71.4% respectively. The numbers of true positive, true negative, false positive, and false negative cases of $^{99m}Tc$-Tetrofosmin were 31,10, 5, and 2 respectively. The sensitivity, specificity, positive predictive value, negative predictive value of $^{99m}Tc$-Tetrofosmin were 93.9%, 66.7%, 86.1%, and 73.3% respectively. One patient was false negative in both $^{99m}Tc-MIBI\;and\;^{99m}Tc$-Tetrofosmin acintimammographies and its size was 0.5 cm. Conclusion: $^{99m}Tc-Tetrofosmin\;and\;^{99m}Tc-MIBI$ were non-invasive and useful in detection of breast cancer and $^{99m}Tc$-Tetrofosmin was comparable to the $^{99m}Tc$-MIBI in detection of primary breast cancer.

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Pediatric Urolithiasis: Our 22-year Experience at a Single Center (소아에서의 요로결석: 단일기관에서 22년간의 경험)

  • Kim, Su-Yon;Kim, Min-Jee;Lee, Joo Hoon;Kim, Kun Suk;Park, Young Seo
    • Childhood Kidney Diseases
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    • v.17 no.2
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    • pp.101-109
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    • 2013
  • Purpose: Pediatric urolithiasis is uncommon in children but is a cause of significant morbidity and damage to the kidney. Although much information on adult urolithiasis is available in the literature, large studies on the pediatric population are still scarce. In this report, we review our experience with pediatric urolithiasis over 22 years at a tertiary referral center. Method: We retrospectively reviewed the records of children with newly diagnosed urolithiasis between January 1991 and May 2013. We assessed the age, sex, family history, initial symptoms, location of stones, underlying cause, stone analysis, treatment, and recurrence among the patients. Results: In total, 137 patients (96 male, 41 female) were assessed. The age range was 0-17 years (mean age, 6.0 years). Forty-three (31%) children were aged <1 year, and 37% (16/43) had a history of intensive care unit (ICU) admission. Thirteen patients (9.5%) had a family history of stones. The most common symptoms at presentation among the patients were gross hematuria (56/137, 41%) and flank or abdominal pain (46/137, 34%). The stones were located in the kidney (85/137, 62%), ureter (29/137, 21%), bladder (2/137, 1.4%), and multiple locations (20/137, 15 %). Congenital abnormalities of the genitourinary (G-U) tract, with or without metabolic abnormality, or urinary tract infection (UTI) was detected in 26 children (19%). Ninety-one patients (66%) underwent metabolic examination, and 38% of these patients exhibited an abnormality. UTI, with or without abnormalities of the G-U tract, or metabolic abnormality was detected in 26 children (19%). Of the 35 stones analyzed, the majority were calcium stones (20/35, 57%), followed by infected stones (5/35, 14%), uric acid stones (4/35, 11%), carbonate apatite stones (3/35, 7%), cystine stones (2/35, 6%), and phosphate stones (1/35, 3%). Five patients (4%) required open procedures, with or without non-open procedures, whereas 77 patients (56%) were managed conservatively; the remaining 55 patients (40%) received some other form of intervention. Eighteen patients (13%) had stone recurrence during the follow-up period. Conclusions: Pediatric urolithiasis is commonly associated with abnormalities of the G-U tract and/or metabolic disorders and/or UTI. Half of the patients will pass their stones spontaneously, and all the techniques of minimally invasive surgery are applicable in the treatment of children with stones. As the recurrence rates are high among this population, long-term follow-up is recommended and the complete clearance of stones is important.

Comparison of the Diagnostic Performance of $^{14}C$-urea Breath Test According to Counting Method for the Diagnosis of Helicobacter pylori Infection (Helicobacter pylori 감염 진단 시 $^{14}C$-요소호기검사의 계수측정 방법에 따른 진단성능 비교)

  • Kim, Min-Woo;Lim, Seok-Tae;Lee, Seung-Ok;Sohn, Myung-Hee
    • The Korean Journal of Nuclear Medicine
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    • v.39 no.1
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    • pp.21-25
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    • 2005
  • Purpose: $^{14}C$-urea breath test (UBT) is a non-invasive and reliable method for the diagnosis of Helicobacter pylori (HP) infection. In this study, we evaluated the diagnostic performance of a new and rapid $^{14}C$-UBT (Heliprobe method), which was equipped with $Geiger-M\ddot{u}ller$ counter and compared the results with those obtained by using the conventional method. Materials and Methods: Forty-nine patients with dyspepsia underwent gastroduodenoscopy and $^{14}C$-UBT. A 37 KBq $^{14}C$-urea capsule was administered to patients and breath samples were collected. In Heliprobe method, patients exhaled into a Hellprobe BreathCard for 10 min. And then the activities of the BreathCard were countered using Heliprobe analyzer. In the conventional method, results were countered using liquid scintillation counter. During gastroduodenoscopy, 18 of 49 patients were underwent biopsies. According to these histologic results, we evaluated the diagnostic performance of two different methods and compared them. Also we evaluated the concordant and disconcordant rates between them. Results: In all 49 patients, concordant rate of both conventional and Heliprobe methods was 98% (48/49) and the discordant rate was 2% (1/49). Thirteen of 18 patients to whom biopsies were applied, were found to be HP positive on histologic results. And both Heliprobe method and conventional method classified 13 of 13 HP-positive patients and 5 of 5 HP-negative patients correctly (sensitivity 100%, specificity 100%, accuracy 100%). Conclusion: The Heliprobe method demonstrated the same diagnostic performance compared with the conventional method and was a simpler and more rapid technique.