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Drug use and HIV infection may affect sex hormone levels in women. One hundred and ninety-six women with and without a history of illicit drug use (50 HIV-negative and 148 HIV-infected), with regular menses, who never used antiretrovirals, were evaluated. Luteinizing hormone levels were significantly higher in women with a CD4 cell count <200/microl (p < 0.002). Current methadone use was associated with lower levels of total testosterone (p = 0.03) and higher levels of prolactin (p = 0.002); mean estradiol levels were 43% lower in women who used intravenous drugs (p < 0.001). Alcohol and crack cocaine use was not associated with sex hormone levels. Age, race, body mass index and degree of HIV immunosuppression were also associated with differences in sex hormone levels.  相似文献   
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Allogeneic hematopoietic stem cell transplantation (HSCT) is established therapy for selected patients with acute leukemia. After transplantation, antileukemic immune responses are believed to eliminate residual leukemia cells and decrease the likelihood of relapse. However, the clinical effect of successful antigen-specific immune reconstitution after HSCT on the likelihood of leukemic relapse and overall survival is not known. Pediatric recipients of unrelated cord blood transplants who underwent transplantation for acute leukemia were sequentially evaluated for their development of antigen-specific T-lymphocyte immunity to herpes viruses. The clinical effect of a positive antigen-specific response on relapse-free survival was determined. The presence of an antigen-specific response resulted in a relapse-free survival advantage (P = .0001), which was primarily due to a decrease in leukemic relapse (P = .003). Proportional hazards modeling for time to relapse and time to relapse or death defined 3 variables that were strongly associated with a poor outcome: female gender, poor remission status before transplantation, and negative antigen-specific T-lymphocyte proliferation. Notably neither acute nor chronic graft-versus-host disease had any effect on the incidence of leukemic relapse. Successful antigen-specific immune reconstitution after unrelated cord blood transplantation results in decreased leukemic relapse and improved overall survival.  相似文献   
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Abstract:  We describe a patient with acquired alpha-thalassemia myelodysplastic syndrome (ATMDS). A previously healthy 66-year-old man presented with hemoglobin of 9.3 g/dL, mean corpuscular volume 59 fL, and a bone marrow aspirate with increased erythroid precursors and hypolobulated megakaryocytes. Hemoglobin H inclusions were seen in most red cells after 1% brilliant cresyl blue supravital stain of the peripheral blood. At the molecular level, we identified of a novel mutation in the most 3' exon of the ATRX gene ( C GA→ T GA substitution in codon 2407) resulting in a premature termination codon (p.R2407X). This case provides further evidence for a link between ATRX mutations and ATMDS, and suggests a possible role for the conserved Q-box element in ATRX function.  相似文献   
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We investigated whether structural white matter abnormalities, in the form of disruption of axonal coherence and integrity as measured with diffusion tensor imaging (DTI), constitute an underlying pathological mechanism of idiopathic dystonia (ID), independent of genotype status. We studied seven subjects with ID: all had cervical dystonia as their main symptom (one patient also had spasmodic dysphonia and two patients had concurrent generalized dystonia, both DYT1‐negative). We compared DTI MR images of patients with 10 controls, evaluating differences in mean diffusivity (MD) and fractional anisotropy (FA). ID was associated with increased FA values in the thalamus and adjacent white matter, and in the white matter underlying the middle frontal gyrus. ID was also associated with increase in MD in adjacent white matter to the pallidum and putamen bilaterally, left caudate, and in subcortical hemispheric regions, including the postcentral gyrus. Abnormal FA and MD in patients with ID indicate that abnormal axonal coherence and integrity contribute to the pathophysiology of dystonia. These findings suggest that ID is not only a functional disorder, but also associated with structural brain changes. Impaired connectivity and disrupted flow of information may contribute to the impairment of motor planning and regulation in dystonia. © 2006 Movement Disorder Society  相似文献   
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Impairment of venous outflow from the liver manifests as zone 3 sinusoidal dilatation and congestion (SDC) in liver biopsy. The spectrum of histologic changes in portal tracts has not been described. We studied liver biopsies from 34 patients with a confirmed diagnosis of venous outflow impairment (VOI). Liver transplant recipients and biopsies with cirrhosis and hepatic neoplasms were excluded. Clinical records were reviewed for laboratory tests and radiographic findings. In all, 19 patients had right heart disease, 13 had classic Budd-Chiari syndrome and two had veno-occlusive disease. Liver chemistry tests showed elevated liver transaminases (n=21; 61.8%), elevated alkaline phosphatase (n=31; 91.2%) and GGT (all 13 cases tested). The elevation in ALT and AST was mild (below 200 U/l in all cases), while alkaline phosphatase (ALP) was elevated above 500 U/l in nine (26.5%) patients and above 1000 U/l in three cases. On biopsy, all cases showed SDC. The portal tracts showed (a) portal expansion with bile ductular proliferation (n=16; 47.1%) accompanied by lymphoplasmacytic infiltrate (n=10), lymphocytic cholangitis (n=3) and portal or periportal fibrosis (n=11), (b) Portal and/or periportal fibrosis without ductular proliferation (n=3; 8.8%) or (c) Normal portal tracts (n=15; 44.1%). The combination of elevated ALP and bile ductular changes on biopsy suggested chronic bile duct disease. Ultrasound/CT scan evaluation of bile ducts in 26 patients showed no biliary tree abnormality. Antimitochondrial antibody testing in eight cases also yielded negative results. In conclusion, bile ductular proliferation, portal inflammation and portal-based fibrosis are commonly seen in liver biopsies of patients with VOI even in the absence of bile duct disease. These changes are often accompanied by elevated ALP and GGT and can lead to the suspicion of chronic biliary disease. In the absence of demonstrable abnormalities in the biliary tree, these changes can be attributed to venous outflow impairment.  相似文献   
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This investigation tested the hypotheses that picrotoxin, a drug which blocks the inhibitory effect of gamma-aminobutyric acid (GABA), would, in spinal cord-transected rats, (1) suppress the cardiac vagus when localized to the forebrain and stimulate the cardiac vagus by acting in the brainstem and (2) stimulate the release of vasopressin into the systemic circulation through separate forebrain and brainstem GABAergic mechanisms. An intra-arterial infusion technique allowed for delivery of picrotoxin selectively to either forebrain or brainstem areas. Administration of picrotoxin via the vertebral artery decreased sinus rate and increased circulating levels of vasopressin. Infusion of picrotoxin into the internal carotid artery caused increases in sinus rate, blood pressure and plasma vasopressin. These data support the hypothesis that GABAergic mechanisms at different levels of the neuraxis exert opposite effects on cardiac vagal activity, and that GABAergic mechanisms in both the brainstem and forebrain inhibit the release of AVP into the systemic circulation.  相似文献   
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