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991.
BACKGROUND: Despite growing evidence for involvement of the dopaminergic system in obsessive-compulsive disorder (OCD), the functional anatomy of the dopaminergic system in the basal ganglia has been investigated sparsely. METHODS: Dopamine D(2) receptor binding was assessed in 10 medication-free OCD patients and 10 healthy control subjects, matched for age, gender, and handedness. The binding potential was measured with single photon emission computerized tomography (SPECT) and infusion of the D(2) receptor radiotracer [(123)I] iodobenzamide. With magnetic resonance imaging as reference, regions of interest (caudate and putamen) were delineated for each hemisphere and coregistered with the corresponding SPECT scans. RESULTS: Dopamine D(2) receptor binding in the left caudate nucleus was significantly lower in the patients with OCD than in healthy control subjects [F(1,18) = 7.0, p =.016]. In addition, an interhemispheric difference was observed in the patient sample. Both the D(2) receptor binding potential (df = 9, p =.012), and the volume (df = 9, p =.029) of the left caudate nucleus were statistically significantly reduced relative to the right caudate nucleus. CONCLUSIONS: This study provides in vivo evidence for abnormalities in the binding potential of the dopamine D(2) receptor, which suggest the direct involvement of the dopaminergic system in the pathophysiology of OCD.  相似文献   
992.
993.
Review of liver biopsy specimens, autopsy specimens, and clinical records of 107 patients with chronic ulcerative colitis and hepatobiliary diseases showed "pericholangitis" (defined as small-duct primary sclerosing cholangitis) in 37 (35%), primary sclerosing cholangitis (defined as large-duct primary sclerosing cholangitis) in 18 (17%), chronic active hepatitis in 14 (13%), cryptogenic cirrhosis in 12 (11%), and miscellaneous lesions including malignancies in 26 (24%). Documented cirrhosis was present or developed in 37 patients (35%). The spectrum of histologic features of small-duct primary sclerosing cholangitis was indistinguishable from that of confirmed large-duct primary sclerosing cholangitis. In 6 of the 18 patients who eventually developed the large-duct disease, biopsy evidence 1 to 12 years earlier had shown small-duct primary sclerosing cholangitis. Thus, small-duct and large-duct primary sclerosing cholangitis seem to be components of a disease spectrum.  相似文献   
994.
We endoscoped 322 of 422 patients with end-stage renal failure undergoing maintenance dialysis treatment to determine the prevalence of erosive prepyloric changes (EPC) in uraemia. EPC grade 1 was found in 79 patients (25%), grade 2 in 16 (5%), and grade 3 in 43 (13%). EPC grades 2 and 3 were commoner among uraemic patients than among non-uraemic patients presenting for gastroduodenoscopy (13 of 198 = 6%; p less than 0.001). Patients with EPC grades 2 and 3 were older, had been receiving dialysis longer, and were more likely to be receiving haemodialysis rather than peritoneal dialysis when compared with patients without EPC. Histologic gastritis of the body and antrum was less common among patients with EPC grades 2 and 3 than among patients without EPC. The prevalence of Campylobacter-like organisms was similar in patients with and without EPC.  相似文献   
995.
BACKGROUND AND AIMS: Nonalcoholic fatty liver disease (NAFLD) could recur after liver transplant in patients with preexisting NAFLD, and has recently been reported to occur after transplant in patients transplanted without preexisting NAFLD. The literature on posttransplant NAFLD is limited. We aimed to study the prevalence of posttransplant NAFLD in patients transplanted for non-NAFLD-related liver diseases. METHODS: Thirty liver transplant recipients: 18 with chronic hepatitis B (CHB), seven with chronic hepatitis C (CHC), five others, were recruited. Liver biopsies were performed in all CHB and CHC patients annually as per protocol, or when clinically indicated. All biopsies were reviewed by one hepato-histopathologist blindly to assess and stage for steatosis and steatohepatitis. RESULTS: After a mean follow-up of 44+/-4 months, 12 (40%) and four (13%) developed posttransplant steatosis and steatohepatitis, respectively. None developed steatosis-related fibrosis or cirrhosis. Posttransplant steatohepatitis was associated with higher pretransplant body mass index (BMI) (32.3+/-3.9 vs 23.1+/-0.8, P=0.02) and higher BMI at last biopsy (32.5+/-4.3 vs 22.9+/-0.7, P=0.01). CONCLUSION: Posttransplant steatosis is common after liver transplant even in patients transplanted for non-NAFLD-related liver diseases. However, it is mostly benign during our follow-up, with only 13% developing steatohepatitis and none with fibrosis or cirrhosis.  相似文献   
996.
Lim YA  Lee WG  Cho SR  Hyun BH  Sc D 《Vox sanguinis》2004,86(1):54-61
BACKGROUND AND OBJECTIVES: There is paucity of comprehensive data on the blood usage with regard to diagnostic categories of Asian recipients. The purpose of this study is to analyse data for blood usage in a korean university hospital in order to obtain additional information on transfusion practices in relation to diagnoses. MATERIALS AND METHODS: Data of information on patients discharged during the period from March 1996 to February 2002, who have received packed red blood cells (RBC), fresh frozen plasmas (FFP), and platelet components (PLT) were extracted from the computerized registers. We used only the principal four-digit diagnostic categories of the Tenth Revision of International Classification of Diseases. RESULTS: A total of 397 489 units of blood components (RBC 171 916 units; FFP 69 301 units; and PLT 156 272 units) were transfused for 17.2% of all discharged patients. Acute myeloid leukaemia, liver cell carcinoma, advanced gastric cancer, alcoholic or other unspecified cirrhosis of liver were the top 5 diagnoses related with the highest usage of blood component. CONCLUSIONS: The results showed a different blood usage pattern compared to those of previous studies. These provide a baseline transfusion practice at our institution, and the data would help in predicting future blood needs in a variety of diagnostic categories.  相似文献   
997.
998.
Contemporary adjuvant therapy for pancreatic cancer patients following surgical resection includes chemotherapy and chemoradiotherapy. However, the median survival remains approximately 20 months despite multi-modality treatment using gemcitabine or fluoropyrimidine systemic chemotherapy. Adjuvant randomized trials are currently underway to evaluate cytotoxic combinations found to be active in advanced disease including FOLFIRINOX, gemcitabine/nab-paclitaxel and gemcitabine/capecitabine. Immunotherapy using genetically engineered cell-based vaccines had shown promise in resected pancreatic cancer patients during early phase trials, and algenpantucel-L vaccine is currently being evaluated in adjuvant setting in a randomized trial. This review focuses on novel adjuvant therapies currently in clinical evaluation.  相似文献   
999.
Hepatitis B virus (HBV) with various mutations has been reported. The frequency of the natural occurrence of such variants and whether the heterogeneity of these genomic regions correlates with a specific serologic pattern of concurrent hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody (anti-HBs) were investigated. We analyzed the perS/S regions of HBV in six asymptomatic HBV carriers who were seropositive for both HBsAg and anti-HBs (group A), four hepatocellular carcinoma (HCC) patients with concurrent HBsAg and anti-HBs (group B), and five asymptomatic HBV carriers without anti-HBs as controls (group C). PreS/S regions of HBV-DNA were amplified by polymerase chain reaction (PCR), cloned, and sequenced. The results showed that, in some of the samples, a few deletions and numerous point mutations were presented in preS/S regions. One of the HBV carriers with anti-HBs (group A) and an HCC patient with anti-HBs (group B) had point mutations in the "a" determinant, resulting in conversion from Ile-126 of wild-type to Asn-126. The patients with anti-HBs (groups A and B) had a significantly greater divergence rate of amino acid for the preS/S gene compared with controls. Our results suggested that the HBV mutants observed in the preS/S gene may have led to changes in the immunogenicity of the viral particles, and thus influence the viral behavior and clinical course. Therefore, some HBV patients with concurrent HBsAg and anti-HBs may be HBV S mutants. Received: October 12, 1998 / Accepted: March 26, 1999  相似文献   
1000.
Aim and Methods: Obesity in humans is associated with proteinuria and an increased glomerular filtration, possibly related to an increase in glomerular capillary pressure. We investigated in obese and lean Zucker rats (10–12 weeks old) whether this might be related to alterations in the diameter of preglomerular and postglomerular microvessels and their reactivity to the resistance regulator angiotensin II (AngII), using the hydronephrotic kidney model. Results: The obese rats exhibited a hyperinsulinaemic, euglycaemic state and hypertension. Urinary protein concentration and fluid intake were both increased threefold. Basal diameters of distal interlobular arteries (ILAs) and afferent arterioles (AAs) were larger in the obese rat than in the lean rat (ILA: 25.7 ± 0.3 vs. 23.0 ± 0.4 μm and AA: 18.8 ± 0.3 vs. 16.7 ± 0.5 μm, respectively; p ≤ 0.01), while diameters of efferent arterioles (EAs) were smaller in obese animals (14.2 ± 1.1 vs. 18.2 ± 1.2 μm; p ≤ 0.05). AngII induced a concentration‐dependent constriction in ILA, AA and EA with an augmented response in the obese compared with the lean rats. Thus, at higher concentrations, AngII abolished the diameter difference between obese and lean animals in preglomerular microvessels while exaggerating that in postglomerular arterioles. Conclusions: Our data indicate that in obese rats, a vasodilated state in small preglomerular microvessels and a vasoconstricted state in the postglomerular arterioles exist. Although AngII cancelled the former, the latter remained. Therefore, these data reveal periglomerular vascular changes that may play a role in glomerular dysfunction and renal pathology associated with obesity.  相似文献   
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