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994.
OBJECTIVES: A positive tourniquet test is one of several clinical parameters considered by the World Health Organization to be important in the diagnosis of dengue haemorrhagic fever, but no formal evaluation of the test has been undertaken. As many doctors remain unconvinced of its usefulness, this study was designed to assess the diagnostic utility of both the standard test and a commonly employed modified test. METHODS: A prospective evaluation of the standard sphygmomanometer cuff tourniquet test, compared with a simple elastic cuff tourniquet test, was carried out in 1136 children with suspected dengue infection admitted to a provincial paediatric hospital in southern Viet Nam. RESULTS: There was good agreement between independent observers for both techniques, but the sphygmomanometer method resulted in consistently greater numbers of petechiae. This standard method had a sensitivity of 41.6% for dengue infection, with a specificity of 94.4%, positive predictive value of 98.3% and negative predictive value of 17.3%. The test differentiated poorly between dengue haemorrhagic fever (45% positive) and dengue fever (38% positive). The simple elastic tourniquet was less sensitive than the sphygmomanometer cuff, but at a threshold of 10 petechiae (compared with the WHO recommendation of 20) per 2.5 cm2 the sensitivity for the elastic tourniquet rose to 45% (specificity 85%). Other evidence of bleeding was frequently present and the tourniquet test provided additional information to aid diagnosis in only 5% of cases. CONCLUSION: The conventional tourniquet test adds little to the diagnosis of dengue in hospitalized children. The simple, cheap elastic tourniquet may be useful in diagnosing dengue infection in busy rural health stations in dengue endemic areas of the tropics. A positive test should prompt close observation or early hospital referral, but a negative test does not exclude dengue infection.  相似文献   
995.
The uremic syndrome remains poorly understood despite the widespread availability of dialysis for almost four decades. To date, assessment of the biologic activity of uremic toxins has focused primarily on in vitro effects, rather than on specific biochemical pathways or enzymatic activity in vivo. The activity of cytochrome P450 (CYP) 3A4, the most important enzyme in human drug metabolism, is decreased in uremia. The purpose of this study was to assess the effect of hemodialysis and hence varying concentrations of uremic toxins on CYP3A4 activity using the 14C-erythromycin breath test and the traditional phenotypic trait measure, 20-min 14CO2 flux. CYP3A4 activity increased by 27% postdialysis (P = 0.002 compared with predialysis) and was significantly inversely related to plasma blood urea nitrogen concentration (rs= -0.50, P = 0.012), but not to several middle molecules. This is the first study in humans characterizing uremia as a state in which hepatic CYP3A4 activity is acutely improved by hemodialysis.  相似文献   
996.
We report the case of a 60-year-old-woman with a myeloma who was hospitalized with a cholestasis. An endoscopic retrograde cholangiopancreatography was scheduled under general anaesthesia with oral intubation. As the biliary prothesis was placed an air embolism happened. The symptomatic treatment allowed a complete recovery. This complication is rare. The pathophysiology is not well known, we discuss the possible mechanisms.  相似文献   
997.
Postoperative hemorrhage (PH) after duodenopancreatectomy (DP) is frequently lethal. The aim of this study was to delineate guidelines of management. Between August 1994 and July 2003, 172 patients underwent DP for cancer. Altogether, 26 patients were subjected to an institutional protocol (IP) with standard-dose chemoradiation (CRT) and 4 patients to an extrainstitutional protocol (EIP) with high-dose CRT. Sixteen patients (9.3%) were reoperated for PH. Hemorrhage occurred in 23% of irradiated patients (4 EIP, 3 IP) and in 6% of nonirradiated patients [confidence interval (CI) 1.8-6.5]. Pancreatic leak occurred in nine patients with PH (56%). Sentinel bleeding (SB) was noted in eight patients (50%) with a mean delay of 10 days after DP. Overall mortality after hemorrhage was 56%. Morality rates of patients with EIP or IP were, respectively, 100% and 0%. Mortality rates of patients with or without SB were similar. Mortality rates of axial bleeding (hepatic artery, mesenteric vessels) or lateral bleeding (pancreas remnant, splenic vessels) were, respectively, 88% and 25% (CI 1.6-8.6). Completion of pancreatectomy was achieved in 75% without rebleeding. Preoperative high-dose CRT increased the risk of fatal PH. Because SB occurs before massive hemorrhage, prompt reoperation could reduce mortality. Completion of pancreatectomy was essential during reintervention. Axial bleeding supports high mortality. Moving to the left, the pancreatojejunostomy could avoid contact of pancreatic juice with axial vessels in the case of pancreatic leakage. Ligating the gastroduodenal artery during DP had to leave a stump of around 1 cm to facilitate hemorrhage control without ligating the common hepatic artery.  相似文献   
998.
HIV-1 infection of the brain results in a large number of behavioural defecits accompanied by diverse neuropathological signs. However,it is not clear how the virus produces these effects or exactly how the neuropathology and behavioural defecits are related. In this article we discuss the possibility that HIV-1 infection may negatively impact the process of neurogenesis in the adult brain and that this may contribute to HIV-1 related effects on the nervous system. We have previously demonstrated that the development of the dentate gyrus during embryogenesis requires signaling by the chemokine SDF-1 via its receptor CXCR4. We demonstrated that neural progenitor cells that give rise to dentate granule neurons express CXCR4 and other chemokine receptors and migrate into the nascent dentate gyrus along SDF-1 gradients. Animals deficient in CXCR4 receptors exhibit a malformed dentate gyrus in which the migration of neural progenitors is stalled. In the adult, neurogenesis continues in the dentate gyrus. Adult neural progenitor cells existing in the subgranlar zone, that produce granule neurons, express CXCR4 and other chemokine receptors, and granule neurons express SDF-1 suggesting that SDF-1/CXCR4 signaling is also important in adult neurogenesis. Because the cellular receptors for HIV-1 include chemokine receptors such as CXCR4 and CCR5 it is possible that the virus may interfere with SDF-1/CXCR4 signaling in the brain including disruption of the formation of new granule neurons in the adult brain.  相似文献   
999.
OBJECTIVES: A qualitative study was conducted among healthcare staff and district and community leaders in May and June 2002 to describe their perceptions of violence occurring between intimate partners. It focused on male violence towards females, and its forms, consequences and preparedness to act in a rural setting in Vietnam. METHODS: Twenty men and 20 women were strategically selected for focus group discussions and a phenomenographic approach was employed. FINDINGS: Violence was described not only as physical but also, primarily, as affecting women's mental health status. Mental violence was exemplified as verbally offending, ignoring or humiliating a woman. Sexual abuse was mentioned less frequently. IPV was considered to be a private matter, occurring in the home away from relatives, neighbours and the local community. Only very serious cases would seek health care. Divorce and deteriorating family finances were reported as serious consequences, not least for the children. Local reconciliation groups, comprised of trusted community members, played a role in mediating, while health professionals were found to be uninformed about prevalence rates and reluctant to intervene. CONCLUSIONS: Gender-based violence needs to receive attention from policy makers, and effective advocacy programmes are needed at all levels. In Vietnam, partner violence against women seems to be recognized at Government level. At community level, Women's Union staff and local reconciliation groups are prepared to act. However, the subject is surrounded by silence. We found that healthcare workers exhibited a lack of understanding of violence against women as a health problem in their own working environment.  相似文献   
1000.
Laparoscopic resection is not an established treatment for pancreatic tumors. Previous reports, mainly in Europe and Japan, have demonstrated the potential utility of laparoscopic distal pancreatectomy (LDP). However, few reports have been published from the United States. We instituted a pilot program to assess LDP. A total of 11 patients were included from December 2003 to December 2004. All patients were staged with preoperative endoscopic ultrasound and received vaccinations for possible splenectomy. The indications for surgery were as follows: neuroendocrine tumor (n = 7), unspecified tumor (n = 1), and cystic neoplasm (n = 3). All procedures began with diagnostic laparoscopy and intraoperative ultrasound. Three patients underwent laparoscopic enucleation of a discrete pancreatic nodule. In eight patients, LDP was attempted. One patient required conversion to an open procedure. In the other seven patients, the procedure was completed laparoscopically, two with hand-assist. The average operative time was 5 hours and 3 minutes; average length of stay was 5 days; and the splenectomy rate was 57 per cent (n = 4). There was one complication of an infected hematoma. There were no pancreatic leaks, deaths, nor readmissions. LDP with or without splenectomy is feasible and can be performed with minimum morbidity and only slightly increased operative time.  相似文献   
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