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J Debnath Sree Ram S Balani I Chakraborty PD Gupta RK Bindal P Sengupta 《Medical Journal Armed Forces India》2005,61(3):249-252
Background
To evaluate the usefulness and limitations of graded compression ultrasonography in the diagnosis of clinically equivocal cases of suspected acute appendicitis at the setting of mid zonal military hospital of India.Methods
A prospective study, graded compression ultrasonography with self localization was carried out with 3.5 MHz convex, 5 MHz convex and 7.5 MHz linear transducers (Wipro GE) in 69 clinically equivocal suspected cases of acute appendicitis. With maximal compression the anteroposterior diameter of appendix was measured from outer to outer wall. The main criterion for diagnosing appendicitis was demonstration of a non compressible appendix with anteroposterior dimension of 7mm or more.Result
Sonologically 36 (52%) cases were diagnosed as appendicitis. Anteroposterior outer diameter of inflamed appendices ranged from 7mm to 21mm (mean 10.5mm). 30 (83%) of 36 patients could accurately self localize the point of maximum tenderness. There were 01 false positive and 04 false negative cases. Sensitivity and specificity were 89.7% and 96.6% respectively. Positive and negative predictive values were 97.2% and 87.8% respectively. Alternative diagnoses were offered in 33 (47.8%) cases. Amongst these 33 cases, 14(42.4%) had abdominal pain of unknown origin. Gynaecologic, urologic and gastrointestinal aetiologies were established in 10(30.3%), 07(21.2%) and 02(6%) cases respectively.Conclusion
Graded compression ultrasonography superadded with self localization is an accurate means of diagnosing/excluding appendicitis in clinically equivocal cases of acute appendicitis and it is of great value in establishing alternative diagnoses.Key Words: Ultrasonography, Acute appendicitis 相似文献95.
96.
BS Duggal P Tarneja RK Sharma SK Rath RD Wadhwa VSM 《Medical Journal Armed Forces India》2004,60(1):28-30
Retrospective study of 121 cases of adnexal masses which were managed laparoscopically was carried out. The aim of study was to evaluate the safety and effectiveness of laparoscopic management of adnexal masses. In 120 cases, procedure was completed safely with minimum morbidity. In one case laparotomy had to be done to complete the procedure. In 76 cases cystectomy was done, 26 required salpingo-oophorectomy and 19 required only salpingectomy. Histologic evaluation revealed 30 functional cysts, 36 endometriotic cysts, 11 dermoids, 9 serous cystadenomas, 3 mucinous cystadenomas, 11 parovarian cysts, 19 cases of hydrosalpinx and 2 cases of tuberculosis.Key Words: Adnexal mass, Laparoscopy, Ovarian cyst 相似文献
97.
This review examines proposed endocrine-based etiologies of postpartum depression (PPD) and how knowledge of these etiologies may affect future treatments. It is based on a review of papers shedding light on the etiology of PPD with special emphasis on research into endocrine-related depression. A picture of PPD is starting to emerge that suggests a variety of endocrine root causes as well as psychosocial risk factors. Hormones reviewed include progesterone, estradiol and estriol, cortisol, corticotropin-releasing hormone, prolactin, thyroid-stimulating hormone and triiodothyronine/thyroxine. Other substances examined include 3 antithyroid autoantibodies. Better understanding of the physiologic bases for depressive symptoms may lead to correction of the underlying pathology of PPD rather than treatment of symptoms. 相似文献
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Uncoupling protein 2 prevents neuronal death including that occurring during seizures: a mechanism for preconditioning 总被引:9,自引:0,他引:9
Diano S Matthews RT Patrylo P Yang L Beal MF Barnstable CJ Horvath TL 《Endocrinology》2003,144(11):5014-5021
The mitochondrial uncoupling protein (UCP2) is expressed in selected regions of the brain. Here we demonstrate that up-regulation of UCP2 is part of a neuroprotective set of responses to various cellular stresses in vitro and in vivo. PC12 cells, when transfected with UCP2, were protected against free radical-induced cell death. Seizure activity was associated with elevated UCP2 levels and mitochondrial uncoupling activity. In transgenic mice that expressed UCP2 constitutively in the hippocampus before seizure induction, a robust reduction in cell death was seen. Because UCP2 increased mitochondrial number and ATP levels with a parallel decrease in free radical-induced damage, it is reasonable to suggest that mitochondrial UCPs precondition neurons by dissociating cellular energy production from that of free radicals to withstand the harmful effects of cellular stress occurring in a variety of neurodegenerative disorders, including epilepsy. 相似文献
100.
The posterior predictive check (PPC) is a model evaluation tool. It assigns a value (p
PPC
) to the probability that the value of a given statistic computed from data arising under an analysis model is as or more extreme than the value computed from the real data themselves. If this probability is too small, the analysis model is regarded as invalid for the given statistic. Properties of the PPC for pharmacokinetic (PK) and pharmacodynamic (PD) model evaluation are examined herein for a particularly simple simulation setting: extensive sampling of a single individual's data arising from simple PK/PD and error models. To test the performance characteristics of the PPC, repeatedly, real data are simulated and for a variety of statistics, the PPC is applied to an analysis model, which may (null hypothesis) or may not (alternative hypothesis) be identical to the simulation model. Five models are used here: (PK1) mono-exponential with proportional error, (PK2) biexponential with proportional error, (PK2) biexponential with additive error, (PD1) E
max
model with additive error under the logit transform, and (PD2) sigmoid E
max
model with additive error under the logit transform. Six simulation/analysis settings are studied. The first three, (PK1/PK1), (PK2/PK2), and (PD1/PD1) evaluate whether the PPC has appropriate type-I error level, whereas the second three (PK2/PK1), (PK2/PK2), and (PD2/PD1) evaluate whether the PPC has adequate power. For a set of 100 data sets simulated/analyzed under each model pair according to a stipulated extensive sampling design, the p
PPC
is computed for a number of statistics in three different ways (each way uses a different approximation to the posterior distribution on the model parameters). We find that in general; (i) The PPC is conservative under the null in the sense that for many statistics, prob(p
PPC
)< for small . With respect to such statistics, this means that useful models will rarely be regarded incorrectly as invalid. A high correlation of a statistic with the parameter estimates obtained from the same data used to compute the statistic (a measure of statistical sufficiency) tends to identify the most conservative statistics. (ii) Power is not very great, at least for the alternative models we tested, and it is especially poor with statistics that are in part a function of parameters as well as data. Although there is a tendency for nonsufficient statistics (as we have measured this) to have greater power, this is by no means an infallible diagnostic. (iii) No clear advantage for one or another method of approximating the posterior distribution on model parameters is found. 相似文献