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71.
Whole pancreas isografts or allografts (ACI donors, RT1a) with bladder drainage of exocrine secretions were performed in Lewis rats (RR1(1] with streptozotocin-induced diabetes. Urinary amylase, pH, and volume and serum glucose were measured daily. They were analyzed alone, or in combination, to determine patterns in deviations from normal values, from isograft control values, or from a posttransplant baseline in relation to rejection (defined as reversion of plasma glucose of greater than 200 mg/dl) in nonimmunosuppressed recipients. Also studied were the sensitivity and specificity by which such deviations predicted rejection. Functioning grafts were associated with increased urinary amylase and pH compared with normal or diabetic controls; urinary volume was less than that of diabetic rats, but greater than that of normal rats. In nonimmunosuppressed allograft recipients (n = 9), rejection occurred at a mean (+/- SD) of 7.78 +/- 0.44 days. Serum glucose rose to above normal (greater than 134 mg/dl) 1 day before rejection in 3 animals (sensitivity 33%, false negative rate 66%; false positive rate in 9 isograft recipients, 44%). Urinary volume dropped below 3 ml at a mean of 3.17 +/- 0.98 days (range 2-5 days) before rejection in 6 animals (sensitivity 66%, false negative rate 33%; false positive rate 0%). Urinary pH fell below 7.25 at a mean of 3.13 +/- 1.81 days (range 1-5 days) before rejection in 8 rats (sensitivity of 89%, false negative rate 11%; false positive rate 29%). Urinary amylase dropped from a posttransplant peak at a mean of 3.56 +/- 1.42 days (range 1-6 days) before rejection in 9 animals (sensitivity 100%, false negative rate 0%; false positive rate 43%), and dropped below 1500 units per 24 hr at a mean of 2.00 +/- 1.32 days (range 1-5 days) before rejection in 8 animals (sensitivity 89%, false negative rate 11%; false positive rate 0%). A drop in urinary amylase combined with a drop in urinary volume or pH occurred at a mean of 3.22 +/- 1.48 days (range 1-5 days) before rejection in 9 rats (sensitivity 100%, false negative rate 0%; false positive rate 0%). In a separate group of 10 allograft recipients, immunosuppression with prednisone and cyclosporine was begun concomitant with, or within 2 days of, the drop in urinary amylase from the peak value; rejection did not occur in 3 animals and was delayed to a mean of 12.0 +/- 5.0 days posttransplant in 7 animals (P less than .05 compared with the nonimmunosuppressed group).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
72.
刘红刚  郑麟蕃 《中华医学杂志》1994,74(2):92-93,T011
用Warthin-Starry螺旋体特殊染色法及透射电镜观察,分别在19例肉芽肿性唇炎和5例梅罗综合征(MRS)病人的病变组织内发现有螺旋体存在,并对其在光,电镜下的形态和在病变组织内的分布部位进行了描述。经用大刘量青霉素治疗11例病人,10例有效。本结果为MRS的发可能和螺旋体感染有关的推测提供了依据。  相似文献   
73.
应用电子自旋共振波谱仪(ESR)直接检测了缺血-再灌注兔心肌肌浆网自由基的变化,以探讨肌质网系统与氧自由基的关系。实验中将20只兔随机分为再灌注对照组、超氧化物歧化酶(SOD)组、ATP-氯化镁组和人参皂甙Re组。实验结果,g值2.0046处为半醌自由基波谱,其相对浓度各组依次为78.94±2.126,14.46±2.86,20.65±7.65,14.66±3.67(x±SD),对照组与用药组均有显著性差异(P<0.05),表明缺血-再灌注兔心肌肌浆网产生大量的自由基,用ESR可以直接检测到半醌自由基,外源性高能磷酸盐制剂ATP-氯化镁及人参皂甙Re与超氧化物歧化酶一样,发挥清除兔心肌肌浆网自由基的作用。  相似文献   
74.
Mantle cell lymphoma is non-Hodgkin's B-cell lymphoma characterized by the t(11;14)(q13;q32) translocation. Peripheral blood involvement of mantle cell lymphoma is usually associated with a poor prognosis and therefore, its identification is clinically important. In this study, we performed cyclin D1/IgH-probe fusion fluorescence in situ hybridization analysis on 223 peripheral blood samples: 185 from 125 mantle cell lymphoma patients, and 38 normal controls. The cutoff values for the test were established using normal controls. Flow cytometry on peripheral blood and corresponding bone marrow samples was used to evaluate this test. In all, 26% of the 185 peripheral blood samples and 27% of the 161 corresponding bone marrow samples were flow cytometry positive for mantle cell lymphoma. The mean numbers of single and- double-fusion signals and the mean number of CD5/CD19-positive cells, absolute blood lymphocyte count, and white blood cell count were significantly higher in peripheral blood and corresponding bone marrow samples with mantle cell lymphoma-positive flow cytometry. Double-fusion signals were more specific than single-fusion ones. Fluorescence in situ hybridization was far more likely to be positive for mantle cell lymphoma when the peripheral blood and the corresponding bone marrow samples had positive flow cytometry results or morphology (P<0.01). Our study indicates that cyclin D1/IgH-fusion fluorescence in situ hybridization analysis could be used to determine the presence and character of circulating mantle cell lymphoma cells in peripheral blood, thus enhancing our ability to evaluate leukemic mantle cell lymphoma and minimum residual disease.  相似文献   
75.
Migraine is a common subtype of headache. Epidemiological studies have revealed that migraine could be an independent risk factor for ischemic stroke even in elderly subjects. Arterial stiffness is one of the major pathophysiological bases of stroke. In the present study, we cross-sectionally investigated the possible relationship between migraine and arterial stiffness in community-dwelling subjects. The study subjects were independently recruited from two sources (Group A, n=134, 68+/-5 years; Group B, n=138, 68+/-7 years). Augmentation index (AI), the ratio of augmented pressure by the reflection pressure wave to the pulse pressure, was obtained from the radial arterial waveform as an index of arterial stiffness. Brachial blood pressure was also measured simultaneously. Migraine was diagnosed using a previously validated questionnaire. The prevalence of migraine was 5.2% (Group A) and 16.7% (Group B). Subjects with migraine had higher radial AI in both Group A (migraine, 101+/-15%; other headache, 88+/-12%; no headache, 86+/-12%, p=0.003) and Group B (95+/-11%, 90+/-11%, 91+/-14%, p=0.058). Multiple linear regression analysis revealed that migraine was an independent determinant of AI (beta=0.154, p=0.002) after adjustment for other confounding factors: age (beta=-0.024, p=0.654); sex (beta=0.141, p=0.069); body height (beta=-0.215, p=0.005); systolic blood pressure (beta=0.174, p=0.001); medication for hypertension, hyperlipidemia, and diabetes mellitus (beta=-0.014, p=0.787); and heart rate (beta=-0.539, p<0.001). In a separate analysis by sex, migraine was also a significant determinant for AI (male, beta=0.246, p=0.019; female, beta=0.159, p=0.008). Migraine in the elderly could be a clinical manifestation of enhanced arterial stiffness.  相似文献   
76.
Pulse-height and time spectra of afterpulses from a scintillation detector with NE102A scintillator sandwiching a 60Co source were observed at several different temperatures. From time analysis with a slow amplifier followed by a conventional TAC, spurious pulses are grouped into two types; time-dependent afterpulses and random noise. The intensity of afterpulses decreased considerably with increasing temperature, while the intensity of random noise pulses increased abruptly above 50 degrees C. Experiments, in which the temperatures of scintillator sheets and of the photomultiplier tube were changed separately, suggested that the time-dependent afterpulses were produced in the scintillator itself, while the random component arose from photomultiplier tube.  相似文献   
77.
Clinical diagnosis of chronic cholecystitis is made based on diffuse hyperechoic thickening of the gallbladder wall as shown by ultrasonographic examination. We herein report three cases of chronic cholecystitis showing localized hypoechoic thickening of the gallbladder wall that mimicked gallbladder cancer by ultrasonography. Histologically, hypertrophy of the muscularis propria was a common characteristic finding in these three patients. A smooth surface of the inner hypoechoic layer of the thickened wall was considered to be a reliable finding in the differential diagnosis between this type of chronic cholecystitis and gallbladder cancer.  相似文献   
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