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排序方式: 共有521条查询结果,搜索用时 15 毫秒
101.
Brajendra K Singh Nicholas J Savill Neil M Ferguson Chris Robertson Mark EJ Woolhouse 《BMC public health》2010,10(1):726
Background
Key to the control of pandemic influenza are surveillance systems that raise alarms rapidly and sensitively. In addition, they must minimise false alarms during a normal influenza season. We develop a method that uses historical syndromic influenza data from the existing surveillance system 'SERVIS' (Scottish Enhanced Respiratory Virus Infection Surveillance) for influenza-like illness (ILI) in Scotland. 相似文献102.
BACKGROUND AND AIMS: Endoscopic stent insertion is the optimum method of palliation for malignant biliary obstruction. Metal stents have several advantages over the polyethylene alternatives, but are significantly more expensive. It has been reported that patients need to survive beyond 6 months to make metal stents more cost-effective. The aim of this study was to audit the performance of expanding metal biliary stents in our endoscopy unit, and to identify factors that might help with patient selection. METHODS: The records of all patients who were selected for endoscopic metal stent insertion at the Royal Perth Hospital for malignant biliary obstruction between September 1994 and November 1998 were reviewed. RESULTS: Thirty-two patients (16 males, mean age 71 years (range 34-88 years) were identified and followed up for a mean 201 days (range 3-810 days). Fifteen (47%) had cholangiocarcinoma, 13 (41%) had pancreatic cancer, and four had metastatic disease as the cause of obstruction. Mortality rates after metal stent insertion were 16, 41 and 55% at 30, 90 and 180 days, respectively. In total, 24 (75%) patients died during the follow-up period. Eleven (34%) stents became obstructed during follow up with a median time to occlusion of 125 days (range 44-729 days). Patients with cholangiocarcinoma had significantly longer survival than pancreatic cancer cases (median 286 vs 58 days, P = 0.04). No other factors were found to correlate with the survival or stent complications. CONCLUSIONS: Less than half of this mixed cohort survived beyond 6 months. Metal stent palliation of malignant biliary obstruction should probably be targeted at those with cholangiocarcinoma, as these patients tend to survive longer. 相似文献
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104.
We report a new bleeding disease--storage pool deficiency (SPD) of platelets--in pigs from the Mayo swine colony of homozygous von Willebrand's disease (vWD) and of heterozygous carriers of vWD. Levels of factor VIII, von Willebrand factor antigen (vWF:Ag), and ristocetin cofactor (RCof) were similar in the vWD carriers and SPD pigs. The latter pigs, however, had bleeding times of 15 minutes or more and were severe bleeders, in contrast to clinically normal vWD carriers. Platelet aggregation in response to collagen was reduced in most SPD pigs. Total platelet content of ADP, ATP, and serotonin was less than that of normal pigs. While the initial uptake of 14C-labeled serotonin into platelets was similar in SPD and normal pigs, retention of serotonin was reduced in platelets of SPD pigs. Transmission electron microscopy showed a large decrease of dense bodies in the platelets of SPD pigs. These findings support a diagnosis of SPD. Genetic analyses suggest an autosomal recessive mode of inheritance. A breeding program is under way to produce pigs affected only at the SPD gene, thus allowing further characterization of SPD and SPD-carrier pigs. 相似文献
105.
Because there was a possibility that activated factor XIII (factor XIIIa) might stabilize a platelet-fibrinogen aggregate through its crosslinking action, we have isolated plasma factor XIII, activated it, and studied the effect of factor XIIIa at a concentration of 3.3 micrograms/ml on aggregation and 125I-fibrinogen binding of rabbit platelets stimulated with 9 microM ADP. Factor XIIIa did not cause aggregation in the absence of ADP, nor did it enhance ADP-induced aggregation or substantially stabilize the platelet aggregate. The presence of factor XIIIa did not affect the amount of fibrinogen bound to platelets immediately after stimulation with ADP, but it appeared to cause a slow specific binding of 125I-fibrinogen to platelets whether or not they were stimulated with ADP. This binding, which was not inhibited by prostaglandin E1, did not lead to aggregation and was accompanied by crosslinking of fibrinogen through its A alpha and gamma chains, either to other fibrinogen molecules or to a platelet protein or proteins. 相似文献
106.
107.
108.
EJ Estlin MK Bennett JR Skinner DWA Milligan C Wren 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(12):1304-1306
A female infant born at 28 weeks' gestation was found to have mild hydrops foetalis. Initial echocardiography showed a structurally normal heart. During the first week of life, episodic atrial tachycardia with 1:1 or 2:1 conduction was seen, requiring therapy with digoxin. The infant remained ventilator dependent, with a persistent, chylous pleural effusion which contained a preponderance of lymphocytes. Congenital pulmonary lymphangiectasia (CPL) was confirmed histologically. Worsening episodes of atrial tachycardia, including episodes of atrial fibrillation, were further investigated and a repeat echocardiogram revealed thickening of the entire right atrial wall. The cardiac findings of a thickened right atrial wall with the histological signs of myocarditis were thought to be the cause of paroxysms of atrial fibrillation, an extremely rare arrhythmia in the neonatal period. To the authors' knowledge there have been no previous reports of CPL in association with the cardiac abnormalities described herein. 相似文献
109.
Esophageal rupture: complication of balloon dilatation 总被引:1,自引:0,他引:1
110.
Abdominal tuberculosis: CT evaluation 总被引:23,自引:0,他引:23
The computed tomography (CT) scans of 27 patients with abdominal tuberculosis were reviewed retrospectively to determine the range of abdominal involvement. Most patients had been at increased risk because of intravenous drug abuse, alcoholism, acquired immunodeficiency syndrome (AIDS), cirrhosis, or steroid therapy. The etiologic agent was Mycobacterium tuberculosis in 23 patients and M. avium-intracellulare in four patients with AIDS. In five patients, tuberculosis was limited to the abdomen. CT findings included adenopathy, splenomegaly, hepatomegaly, ascites, bowel involvement, pleural effusion, intrasplenic masses, and intrahepatic masses. Characteristic features were a tendency for adenopathy to prominently involve peripancreatic and mesenteric compartments, low-density centers within enlarged nodes, complex nature of the ascites, and adenopathy adjacent to sites of gastrointestinal tract involvement. Recognition of these manifestations and maintenance of an index of suspicion, especially in patients at risk, should help optimize the correct diagnosis and management of intraabdominal tuberculosis. 相似文献