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991.
Anand V Sen S Jacob R Chacko J Zachariah N Thomas G Mammen KE 《Pediatric surgery international》2001,17(1):29-31
During the period 1994–1998, three patients with bilateral hydatid cysts of the lung (HCL) underwent operative removal of
the cysts. In three of the six lungs operated upon the conventional technique was used: after removal of the cyst and suture
closure of bronchial leaks, the chest was closed with an intercostal drainage tube. Two of these patients developed bronchopleural
fistulae requiring rethoracotomy and prolonged hospital stays. The other three lungs were operated upon using the pneumonostomy
technique: after excision of the cyst a separate catheter is fixed within the residual lung cavity and brought out through
the adjacent chest wall, effectively marsupialising the residual cavity to the atmosphere. All these patients had an uneventful
postoperative recovery. We conclude that the pneumonostomy technique is a very useful method of treating HCL surgically, especially
when the cysts are bilateral and complicated.
Accepted: 13 January 2000 相似文献
992.
Quantitative regional analysis of myocardial wall motion 总被引:4,自引:0,他引:4
This paper presents a new technique for semiautomatic quantification of regional heart function from 2-D echocardiography. It uses a novel left ventricular border tracking algorithm based on shape-space ideas that we have recently described. In this paper, we show how to decompose the tracked output into clinically meaningful segmental parameters (wall excursion and thickening), using what we call a computational interpretational space (CIS). This leads to a quantitative and automatic scoring scheme for endocardial excursion and myocardial thickening. The method is illustrated on data from a patient with a myocardial infarct in the apical anterior/inferior region of the heart and is also assessed in a small retrospective dobutamine stress echocardiography clinical case study. 相似文献
993.
Nattermann J Nischalke HD Kupfer B Rockstroh J Hess L Sauerbruch T Spengler U 《AIDS (London, England)》2003,17(10):1457-1462
INTRODUCTION: Epidemiological data demonstrate an association between hepatitis G virus (HGV) co-infection and improved survival of HIV-positive individuals. However, the mechanism by which HGV affects progression of HIV disease remains unclear. As down-regulation of CC chemokine receptor 5 (CCR5) delays HIV progression, we investigated whether CCR5 expression is altered by exposure of lymphocytes to HGV proteins. METHODS: A cross-sectional analysis of CCR5 expression was carried out on CD4 and CD8 T lymphocytes of 11 HGV-positive and 12 HGV-negative persons, who were homozygous for the CCR5 wild-type gene. Binding of the HGV E2 protein to CD81 was analysed by flow cytometry. Lymphocytes were stimulated with immobilized HGV E2, anti-CD81 or serum proteins from HGV-infected subjects and changes in CCR5 expression and CC chemokine secretion were determined. RESULTS: We demonstrate that the HGV envelope protein E2 specifically binds to CD81 on T lymphocytes. This interaction induces a dose-dependent release of RANTES and down-regulation of CCR5 surface expression with concomitant intra-cellular accumulation of CCR5 proteins. This effect of HGV E2 on CCR5 expression was confirmed when lymphocytes were incubated with serum proteins from HGV-infected subjects. Finally, our cross-sectional analysis revealed CCR5 expression to be reduced by 53% and 36% on CD4 and CD8 lymphocytes of HGV-infected subjects, respectively (P < 0.01). CONCLUSIONS: Our results demonstrate that an interaction of HGV E2 with CD81 leads to increased RANTES secretion and decreased CCR5 surface expression. This mechanism might contribute to the delayed progression of HIV-infection in HGV-coinfected patients. 相似文献
994.
Effects of sex steroids on components of the insulin resistance syndrome in transsexual subjects 总被引:2,自引:0,他引:2
Elbers JM Giltay EJ Teerlink T Scheffer PG Asscheman H Seidell JC Gooren LJ 《Clinical endocrinology》2003,58(5):562-571
OBJECTIVE: Sex differences are found in most components of the insulin resistance syndrome and the associated cardiovascular risk profile. These differences are attributed to sex-specific sex steroid profiles, but the effects of sex steroids on the individual components of the insulin resistance syndrome remain incompletely understood. DESIGN: Prospective, intervention study. SUBJECTS: In 37 young (age range 16-36 years), nonobese [body mass index (BMI) < 29], transsexual subjects, effects of ethinyl oestradiol (100 micro g/day) + cyproterone acetate (100 mg/day) administration were evaluated in 20 male-to-female transsexuals and of testosterone-ester administration [250 mg intramuscularly (i.m.)/2 weeks] in 17 female-to-male transsexuals. MEASUREMENTS: We studied lipid spectrum, postheparin hepatic lipase (HL) and lipoprotein lipase (LPL) activity, blood pressure, glucose utilization (by euglycaemic hyperinsulinaemic clamp), and fat areas (by magnetic resonance imaging) at baseline and during 1-year cross-sex hormone administration. RESULTS: Oestrogens + antiandrogens increased high-density lipoprotein (HDL)-cholesterol and decreased LDL-cholesterol, and HL activity, which are considered beneficial. But this combination also increased triglycerides, blood pressure, subcutaneous fat and visceral fat, and decreased the LDL-particle size, LPL activity and insulin sensitivity, which are all considered detrimental. Testosterone reduced HDL-cholesterol and the LDL-particle size, and increased triglycerides and HL activity. An android fat distribution was induced (i.e. decreased subcutaneous and increased visceral fat). Blood pressure, total and LDL-cholesterol, LPL activity and insulin sensitivity were mainly unaffected. CONCLUSIONS: The effects of cross-sex hormone treatment - in the dosages used in this study - in healthy, nonobese, young transsexual subjects do not show unequivocally that female sex steroids, given in large amounts to male subjects, have beneficial effects on cardiovascular profile and that high dose testosterone administration to female subjects is detrimental with respect to cardiovascular risk. 相似文献
995.
996.
Coverdale SA Samarasinghe DA Lin R Kench J Byth K Khan MH Crewe E Liddle C George J Farrell GC 《The American journal of gastroenterology》2003,98(6):1384-1390
OBJECTIVE: We tested whether fibrotic progression in chronic hepatitis C could be predicted by liver tests, antipyrine clearance, or platelet count. METHODS: In 58 patients (6 untreated, 52 interferon-treated), a second liver biopsy was taken median 4.5 yr after first histologic diagnosis. We used receiver operating characteristic curves to determine whether changes in conventional liver tests, antipyrine clearance, or platelet count were predictive of altered hepatic fibrosis score. RESULTS: Apart from a weak association with change in ALT, conventional liver tests (albumin, bilirubin, prothrombin time) failed to correlate with changes (Delta) in hepatic fibrosis, but there were significant correlations between deltaantipyrine clearance or deltaplatelet count and deltafibrosis score (p < 0.01). As indicated by areas under the receiver operating characteristic curves, the diagnostic accuracy of deltaantipyrine clearance for fibrotic progression was 68%; for Deltaplatelet count it was 80%. With defined cut-off values (-0.05 ml/min/kg for deltaantipyrine clearance; -41 x 10(9)/L for deltaplatelet count), the negative predictive values for fibrotic progression were 85% with antipyrine clearance and 89% with platelet count. Corresponding positive predictive values were 48% and 91%, respectively. CONCLUSIONS: Changes in antipyrine clearance and platelet count are more sensitive than conventional tests for indicating fibrotic change in chronic hepatitis C. Both could be used to reliably identify those who do not have fibrotic progression, and platelet count also has a high positive predictive value for disease progression. 相似文献
997.
Safety of nitrate withdrawal in angina-free and hemodynamically stable patients with coronary artery disease 总被引:1,自引:0,他引:1
STUDY OBJECTIVES: To assess the consequences of nitrate withdrawal in angina-free and hemodynamically stable coronary patients. DESIGN: Prospective, open, intervention study. SETTING: Cardiology outpatient clinic of a university-affiliated municipal hospital. PATIENTS: Angina-free patients who were hemodynamically stable for at least 3 months before study onset were enrolled. They were all regularly receiving nitrates for symptom control. Those with significant reasons to avoid stopping nitrates, such as heart failure (ejection fraction <35%) or high BP (> 160 mm Hg systolic and/or > 100 mm Hg diastolic), and noncompliant patients were excluded. INTERVENTIONS: After providing informed consent and undergoing an exercise test (whenever possible), the participants were randomized to abruptly discontinue (study group) or continue (control group) nitrate treatment. Follow-up continued for at least 3 months after study entry. MEASUREMENTS AND RESULTS: Eighty patients were randomized to the study group and 40 patients to the control group (mean age [+/- 1 SD], 65.5 +/- 11 years and 66.1 +/- 10.9 years, respectively; p = not significant). The first month, eight study patients (10%) had a recurrence of anginal symptoms, compared with one control subject (2.5%) [p = not significant]. All eight patients responded promptly and favorably to the resumption of nitrate administration. CONCLUSIONS: Nitrate administration can be safely discontinued in angina-free and hemodynamically stable coronary patients who receive this medication on a regular basis. If relapse of anginal symptoms occurs, it will be within 1 month following nitrate withdrawal, and will resolve satisfactorily with reinstatement of treatment. 相似文献
998.
Buchowski JM Helm PA Huckell CB Riley LH Cohen DB Ahn NU Ahn UM Okubadejo GO Zinreich SJ Kostuik JP 《American journal of orthopedics (Belle Mead, N.J.)》2003,32(2):90-7; discussion 97
Computer-assisted pedicle screw insertion is feasible but has proved to be problematic. The purpose of this study was to detail the accuracy of registration techniques and pedicle screw insertion using a frameless stereotactic system. Two registration techniques were evaluated on a model spine. The frameless stereotactic system was then used to insert 26 pedicle and 8 lateral mass screws in human cadavers. For posterior vertebral elements, trajectory accuracy was 2.5 +/- 1.0 mm between T12 and L5 and 2.2 +/- 0.9 mm between C2 and T1. Registration of the anterior elements, however, was less accurate. Despite this flaw, all screws were inserted without penetrating the cortex. Screw trajectory was accurate to 2 degrees. The main limitation of frameless stereotactic surgery in the spine stems from the fact that only the posterior vertebral elements are used during registration. Despite this flaw, the system placed all screws correctly. Given these limitations, we believe that this system is most useful for locating the screw insertion point and providing a trajectory in the pedicle. 相似文献
999.
1000.
The acronym PEMPHIGUS is suggested to encompass the numerous factors involved in the pathogenesis and course of the disease. In the following review the authors present studies documenting these factors. The acronym can serve as a handy tool to direct the physician's investigation of a case of pemphigus, aiding in its diagnosis and in the prevention of future flare-ups. 相似文献