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61.
Ischemia of the intestines damages the permeability of the intestinal wall, allowing lipopolysaccharide (LPS) (endotoxin) to leak from the gut lumen into the blood circulation, causing shock and death. We measured LPS levels associated with corticosteroid treatment vs. no treatment in cats whose superior mesenteric artery had been occluded for 60 min. In untreated cats, the preocclusion mean plasma LPS concentration remained stable at 0.069 +/- 0.015 ng/ml. Toward the end of the occlusion period, mean plasma LPS rose to 0.239 +/- 0.032 ng/ml (p less than .01). Release of the clamp and reperfusion with oxygenated blood was followed within 20 min by a large rise in plasma LPS concentration to 0.825 +/- 0.11 ng/ml (p less than .01), which had returned to preocclusion levels about 80 min later. Methylprednisolone (30 mg/kg) was infused into a second group of cats 1.5 h before SMA occlusion. In these cats there was a complete inhibition of the LPS rise both during and after occlusion. These data suggest that the reported beneficial effect of corticosteroids in the treatment of septic shock may be mediated, in part, by reducing LPS leakage from the gut.  相似文献   
62.
63.
Coronary sinus thrombosis was found at necropsy in a girl with spina bifida who underwent ventriculoatrial shunt revision. There was secondary myocardial infarction, close to the conducting system within the interventricular septum. We suggest that this led to cardiac arrest and sudden death.  相似文献   
64.
Avulsion of the acetabular labrum with intraarticular displacement   总被引:1,自引:0,他引:1  
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65.
Surgical management of facial palsy   总被引:1,自引:0,他引:1  
Patients with facial palsy present with a multitude of different problems to which individual solutions must be carefully tailored. Although numerous surgical options exist, the results of reconstruction are rarely ideal. This article discusses different surgical procedures for reconstruction of the eye and mouth with special emphasis on the newer technique of microsurgical transfer of muscle tissue for reanimation.  相似文献   
66.
Two hundred forty-four consecutive patients (mean age 61 years), including 123 who had technically valid renal vein renin (RVR) analysis and 121 without RVR data, underwent technically successful percutaneous renal artery angioplasty (PTRA). They were retrospectively examined to evaluate the utility of RVR analysis in identifying renal hypertension (RVH), predicting benefit from PTRA, and determining if the lack of knowledge of renin levels significantly affected clinical outcome after PTRA. Abnormal RVR values were associated with clinical benefit after PTRA in 62 of 93 patients (67% sensitivity, 20% specificity, 72% positive predictive value). Clinical improvement following PTRA occurred in 31 of 37 patients with normal pre-PTRA RVR values (16% negative predictive value). RVR analysis correctly identified 86 of 117 patients with renovascular hypertension (74% sensitivity, 16% negative predictive value). Improved blood pressure (BP) control occurred in 72% with abnormal RVR analysis and 66% of the 121 patients without RVR data (p>0.1). We conclude that the very low negative predictive value significantly limited the use of RVR analysis in this elderly (mean age 60 years) patient population with a high incidence of mild renal functional impairment (mean serum creatinine 1.4 mg/dl) and bilateral renal artery stenosis (38%). The lack of pre-PTRA renin data did not significantly affect clinical outcome. If RVR data were relied upon as the exclusive selection criterion in patients of this type, many would be prevented from having the benefit of cure or improvement by PTRA.  相似文献   
67.
Bronchiectasis following colectomy for Crohn's disease   总被引:2,自引:0,他引:2       下载免费PDF全文
T Eaton  N Lambie    A Wells 《Thorax》1998,53(6):529-531
Bronchiectasis developing following colectomy for ulcerativecolitis has been reported in a few cases. This may be the first reportof bronchiectasis developing after colectomy for Crohn's disease. Theclose temporal relationship to colectomy, lack of bacterial pathogensin the sputum, and an impressive response to oral steroids suggest adifference in pathogenesis from idiopathic bronchiectasis.

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68.
The use of different approaches to measurement in drug abuse treatment outcome studies has resulted in a lack of comparability across studies. This paper reviews different approaches to timing of baseline and follow-up periods and to dealing with time periods during which follow-up subjects are not "at risk" for drug use. Length and timing of baseline and follow-up periods are considered as well as periods of time within which specific drug use outcomes are measured. It is suggested that research focus on describing the natural course of drug use both prior to and following treatment, in order to determine the most appropriate length and timing of follow-up periods. It is recommended that investigators report drug use data from both "at risk" and "not at risk" periods, and that they choose methods of controlling for time "at risk" which do not eliminate important drug use data from analyses.  相似文献   
69.
Detection bias in the diagnostic pursuit of lung cancer   总被引:2,自引:0,他引:2  
Autopsy studies have shown that lung cancer is often not detected during life and that a correct antemortem diagnosis is made preferentially in patients with pulmonary symptoms, in smokers, and in men. The current research was done as a case-control study to determine whether the autopsy suggestions of detection bias in diagnostic pursuit of lung cancer were confirmed by the way that sputum Papanicolaou smears (Pap smears) were ordered in an inpatient setting. The cases were 385 hospitalized patients in whom sputum Pap tests had been newly performed from October 1977 to September 1980. Each case was matched by age, admission date, and admission diagnosis to a control patient who had not received a Pap test. Excluded from the study were patients in whom sputum Pap tests were obligatory (e.g., those with manifestations of hemoptysis) or unnecessary (e.g., those with a previous diagnosis of lung cancer or multiple previous sputum Pap tests). Demographic data, amount and duration of cigarette smoking, and details of clinical manifestations were extracted from the patients' medical records by research assistants blind to the study hypothesis. Compared with controls, the cases had distinctive elevations in odds ratios for chronic cough, recent cough, male sex, and cigarette smoking, which also showed a distinctive dose-response relation. In multivariate analyses, all four of these "risk factors" for selective ordering of a sputum Pap smear remained independently highly significant. In the extreme category, men who smoked and coughed were 22 times more likely to have a sputum Pap test ordered than were nonsmoking women who did not cough. Clinically, the results suggest that women and nonsmokers may be deprived of appropriate diagnosis and therapy unless a diagnostic workup for lung cancer is guided mainly by radiographic findings and presenting manifestations. Statistically, detection bias has probably led to an excessively elevated magnitude for the cigarette smoking-lung cancer association and to a falsely low estimate of incidence rates in women.  相似文献   
70.
AIMS: To set up a network for remote consultation using static imaging telepathology via Internet connection between pathologists in different European countries, and to collect some numerical and subjective impressions on the usefulness of this form of telepathology. METHODS: A static image remote consultation network between 11 pathologists in nine European countries was set up; all pathologists were equipped with the same telepathology system. The pathologists formed three subject oriented subgroups concerned with prostate, melanoma, and soft tissue sarcoma pathology. Each pathologist sent and received a small number of cases, and data on each case were collected and analysed. The whole experiment was controlled through a World Wide Web site. RESULTS: A total of 56 case consultations on 34 different cases were exchanged. The average case document contained seven images, and contained 1.97 Mbytes of data. For cases in which data were recorded, average case preparation and remote consultation time was 55 minutes and 9.2 minutes, respectively. Transmission times averaged 3.9 minutes. In subjective impressions, reservations were expressed in several cases regarding the confidence that could be given to the diagnosis from the images presented. CONCLUSIONS: Remote consultation by telepathology via the Internet is now technically feasible and reasonably user friendly, but is only suitable as a method of disease diagnosis in some cases.  相似文献   
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