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Scrub typhus usually presents as acute undifferentiated fever. This cross-sectional study included adult patients presenting with acute undifferentiated fever defined as any febrile illness for ≤ 14 days without evidence of localized infection. Scrub typhus cases were defined by an antibody titer of a ≥ fourfold increase in paired sera, a ≥ 1:160 in a single serum using indirect immunofluorescence assay, or a positive result of the immunochromatographic test. Multiple regression analysis identified predictors associated with scrub typhus to develop a prediction rule. Of 250 cases with known etiology of acute undifferentiated fever, influenza (28.0%), hepatitis A (25.2%), and scrub typhus (16.4%) were major causes. A prediction rule for identifying suspected cases of scrub typhus consisted of age ≥ 65 years (two points), recent fieldwork/outdoor activities (one point), onset of illness during an outbreak period (two points), myalgia (one point), and eschar (two points). The c statistic was 0.977 (95% confidence interval = 0.960–0.994). At a cutoff value ≥ 4, the sensitivity and specificity were 92.7% (79.0–98.1%) and 90.9% (86.0–94.3%), respectively. Scrub typhus, the third leading cause of acute undifferentiated fever in our region, can be identified early using the prediction rule.  相似文献   
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Previous studies in this laboratory have demonstrated that the alpha 2-adrenergic agonist clonidine and related drugs can offer significant protection against both the acute and chronic toxicity to soman administration in rats and mice. The purpose of this study was to determine whether addition of clonidine to a standard pretreatment protective regimen against soman toxicity could offer added protection or benefit. The standard regimen employed was a mixture of physostigmine salicylate (150 micrograms/kg) and artane (trihexyphenidyl hydrochloride 2 mg/kg). Rats were randomly assigned to one of 4 experimental groups: (1) those receiving i.m. sterile saline injection followed 30 min later by s.c. saline injection (normal controls); (2) saline, i.m. followed 30 min later by one of several doses (60-110 micrograms/kg of soman, s.c.; (3) saline, i.m., followed 10 min later by the standard pretreatment regimen i.m., followed by one of several doses of soman (160-300 micrograms/kg), s.c.; and (4) clonidine hydrochloride (1 mg/kg) i.m., followed 10 min later by the pretreatment regimen, followed 30 min later by soman. All animals were examined acutely and survivors were examined over a 3-week period following soman administration. The following observations were made: (1) Addition of clonidine to the standard pretreatment regimen did not enhance survival rate over the standard regimen alone (unless the clonidine was administered after the regimen). (2) Of the acutely toxic behavioral signs promoted by soman, clonidine addition to the standard regimen was of benefit only in reducing soman-induced tremor. (3) Addition of clonidine to the standard regimen appeared to hasten the return to normal motor behavior after soman; however, all groups exhibited normal motor behavior in 9 days. (4) Despite apparent normal motor behavior, soman-treated animals exhibited a marked performance deficit in the passive avoidance parameter 3 weeks after injection. The standard regimen partially preserved this effect; addition of clonidine to the standard regimen completely reversed the effect. These results indicate that clonidine provides a measure of protection against chronic behavioral deficits caused by soman intoxication.  相似文献   
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In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
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Although alcoholism is a known risk factor for osteoporosis, there are few published reports on alcoholism-associated bone loss. To study alcoholism-associated bone loss, this study used a dual X-ray absorptiometry (DXA) densitometer to measure lumbar and femoral bone mineral density (BMD) in a previously little-studied population: 32 relatively healthy, nonhospitalized, Caucasian, alcoholic men with a period of abstinence longer than that previously studied (median abstinence 4.0 months, range 3 days–36 months). DXA is a new, highly precise densitometric method with many advantages over the methods used in previous studies. The subjects had statistically significant bone loss at three sites: lumbar spine, femoral neck, and Ward's triangle (multiple correction adjusted two-tailed P < 0.008). Compared to the mean BMD of sex-, age-, and race-matched norms, the subjects' average femoral neck, Ward's triangle, and lumbar BMDs were, respectively, 0.56, 0.69, and 0.57 standard deviations (SDs) below the normative values.This study was partially funded by a National Institutes of Health Short Term Research Training Grant (PHSHL 07491) to K.C.  相似文献   
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The bronchomotor effects of a deep inhalation (DI) may provide relevant information about the mechanisms of exercise-induced airway obstruction in children and may be assessed by respiratory conductance (Grs) measured using the forced oscillation technique. The aims of the present study were to assess the effect of DI on Grs after exercise in relationship to the lung function response to exercise. Grs at 12 Hz using a head generator and spirometric data were measured in 62 children suspected of asthma before and 5 min after a 6-min free run. After exercise, Grs was significantly increased by DI in 38 subjects, who also showed larger Grs and forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) responses to exercise than the 24 nonresponders. Stepwise regression indicated significant correlation between the response of Grs to DI and both Grs and FEV1/FVC responses to exercise. The data are consistent with exercise-induced bronchoconstriction being reversed by deep inhalation.  相似文献   
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Intestinal schistosomiasis japonica: CT-pathologic correlation   总被引:1,自引:0,他引:1  
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