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21.
Despite improved survival after liver transplantation (OLTX) in HIV-positive individuals treated with highly active antiretroviral therapy (HAART), some transplant candidates do not survive to OLTX. To determine if pretransplant outcome is related to severity of liver disease and/or HIV infection, we prospectively evaluated 58 consecutive HIV-positive candidates seen at a single center from 1997-2002. Of the 58, 15 (25.9%) were transplanted, whereas 21 (36.2%) died before OLTX, a median one month of evaluation, with more than half of those (12 of 21, 57.1%) dying from infection. By contrast, of 1,359 HIV-negative candidates, 860 (63.3%) were transplanted, whereas 211 (15.5%) died before OLTX (P < 0.001). The cumulative survival following initial evaluation was significantly shorter among HIV-positive than HIV-negative candidates (880 vs. 1,427 days, P = 0.035, Breslow) but was not related to the initial pretransplant MELD score (16 vs. 15), INR (1.5 vs. 1.5), creatinine (1.3 vs. 1.3 mg/dL), or total bilirubin (6.6 vs. 5.7 mg/dL), respectively, all P > 0.05. Among untransplanted HIV-positive candidates, the 21 who died did not differ from the 22 surviving in initial MELD (15 vs. 13), CD4 (230 vs. 327/microL), HIV load (both < 400 copies/mL), HAART intolerance (10/21, 47.6% vs. 10/22, 45.4%), or HCV infection (16/21, 76.2% vs. 16/22, 72.3%), all P > 0.05. Further, the 21 did not differ from the 15 transplanted in pre-OLTX CD4, HIV load, or MELD score, all P > 0.05. In conclusion, pretransplant survival appears shorter in HIV-positive OLTX candidates and is unrelated to severity of liver or HIV disease. Further study is warranted to determine risk factors for poorer pretransplant outcomes.  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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Multilocus enzyme electrophoresis was used to divide 124 Australian isolates of Streptococcus suis type 2 into 17 electrophoretic types (ETs). Isolates in ET 1 were the most frequent cause of disease amongst Western Australian pigs, but isolates of ET 8 were more commonly associated with disease in other Australian states. Multiple isolates from 10 of 19 farms all belonged to the same ET, whilst isolates from the other farms belonged to between 2 and 4 different ETs. Some isolates could be differentiated further by DNA restriction endonuclease analysis, whilst others with the same restriction pattern were located in different, but closely-related ETs. Fourteen isolates were tested for their virulence in mice. Most caused disease if given in high numbers, but isolates in ET 1 were virulent at lower dose rates. This virulent clone also was distinguished by the fact that 80% of isolates produced extracellular factor (EF).  相似文献   
26.
To determine whether the increase in baroreflex sensitivity previously reported in lifetime captopril-treated spontaneously hypertensive rats (SHR) was due to an inhibition of brain angiotensin II mechanisms, we tested the effect of intracerebroventricular administration of an angiotensin II receptor antagonist on baroreflex control of heart rate in lifetime captopril-treated and untreated male and female SHR. Baroreceptor reflex control of heart rate was assessed by the slope of the relationship between changes in mean arterial pressure (delta MAP, mmHg) and changes in pulse interval (delta PI, ms). MAP was raised and lowered with infusions of phenylephrine and nitroprusside, respectively. Following basal assessment of baroreflex control of heart rate, rats received an intracerebroventricular injection (100 pmol) of Sar1Thr8 angiotensin II (sarthran) and reflex control of heart rate was reassessed. Adequacy of blockade was tested with central and peripheral administration of angiotensin II. Captopril-treated male (130 +/- 7 mmHg) and female (123 +/- 4 mmHg) rats had significantly lower MAP than untreated rats (174 +/- 4 and 173 +/- 8 mmHg, respectively) and enhanced bradycardia in response to increases in MAP. Intracerebroventricular administration of sarthran had no effect on basal blood pressure or heart rate but enhanced the bradycardia in response to increases in MAP in both untreated and captopril-treated rats. The increase in the slope of the line relating delta MAP to delta PT was greater for untreated than captopril-treated SHR (male untreated 2.7-fold versus captopril-treated 1.5-fold; female untreated 1.6-fold versus captopril-treated 1.5-fold).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
27.
Depression is common in Parkinson's disease (PD) and affects 30 to 50% of all patients. In contrast to the wealth of research on depression in PD, little is known about the occurrence of depression in other movement disorders. The primary objective of the current study was to determine whether the high prevalence of depression symptoms seen in PD is also found in other movement disorders, by directly comparing rates of specific depression symptoms and depression severity across PD, dystonia, and essential tremor (ET). Three hundred and fifty-four patients with PD, 83 patients with dystonia, and 53 patients with ET completed the Beck Depression Inventory (BDI). We found no significant between-groups differences for depression severity, frequency, or endorsement of specific depression symptoms. Forty-eight percent of PD patients, 37.3% of dystonia patients, and 34% of ET patients were found to be at least mildly depressed (BDI score of 10 or higher). The most commonly endorsed symptoms were fatigability, difficulty with work, anhedonia, and sleep disturbance. Clinicians should be aware that depression is a frequent problem in dystonia and ET, in addition to PD, and inquire about depression symptoms in these patients so that they can be appropriately treated.  相似文献   
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Reviewed literature on the homeless reports higher rates of psychiatric disorder, psychological distress, and previous psychiatric hospitalization compared to the general population. However, understandardized methodology and lack of consistent findings across studies prohibit reliable prevalence estimates of mental disorder among the homeless.Dr. Robertson is with the Center for Research of Women of Wellesley College, Wellesley, Massachusetts 02181.  相似文献   
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Studies were made comparing the corneal endothelium of bisected human corneas; one half of each was mechanically agitated in McCarey-Kaufman (M-K) medium, while the other half remained static in M-K medium for an equal period of time. Scanning electron microscopic (SEM) analysis of the corneal endothelium suggested that the endothelium of the corneas undergoing agitation does not show deterioration in morphology when compared with the non-agitated group. This finding is significant as donor corneas are now being transported in greater numbers.  相似文献   
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