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41.
To compare human immunodeficiency virus (HIV) type 1 disease progression in patients infected by the predominant strain circulating recombinant form (CRF) 02_AG in western and west-central Africa and in patients infected by other strains, a prospective multicenter cohort study was conducted in Cameroon and Senegal. Among the 335 patients, a broad HIV-1 group M subtype diversity was observed in the envelope V3-V5 region, but strain CRF02_AG predominated in both Cameroon and Senegal (61.2% and 62.9%, respectively; P<.8). Multivariate analyses showed no difference between patients infected by CRF02 strains and those infected by other strains in terms of survival (adjusted hazards ratio [HR], 1.16; 95% confidence interval [CI], 0.76-1.78; P=.5), clinical disease progression (HR, 0.79; 95% CI, 0.50-1.25; P=.3), or square root CD4 cell decline (regression coefficient, -0.01; 95% CI, -0.82 to 0.81; P=.9). This study suggests that the predominance of HIV-1 CRF02_AG strain in western and west-central Africa should have no major clinical consequences.  相似文献   
42.
BACKGROUND/AIMS: Biliary strictures are a serious cause of morbidity after liver transplantation. We have studied the role of altered bile composition as a mechanism of bile duct injury after human liver transplantation. METHODS: In 28 liver transplant recipients, bile samples were collected daily posttransplantation for determination of bile composition. Hepatic expression of bile transporters was studied before and after transplantation. Histopathological criteria as well as biliary concentrations of alkaline phosphatase (ALP) and gamma-glutamyltransferase (gamma-GT) were used to quantify bile duct injury. RESULTS: Early after transplantation, bile salt secretion increased more rapidly than phospholipid secretion, resulting in high biliary bile salt/phospholipid ratio (BA/PL). In parallel with this, mRNA levels of the bile salt transporters NTCP and BSEP increased significantly after transplantation, whereas phospholipid translocator MDR3 mRNA levels remained unchanged. Bile duct injury correlated significantly with bile salt secretion and was associated with a high biliary BA/PL ratio. CONCLUSIONS: Bile salt secretion after human liver transplantation recovers more rapidly than phospholipid secretion. This results in cytotoxic bile formation and correlates with bile duct injury. These findings suggest that endogenous bile salts have a role in the pathogenesis of bile duct injury after liver transplantation.  相似文献   
43.
The clinical features, morphology and immunophenotype of 20 cases of B non Hodgkin's lymphoma (B-NHL) with chromosome abnormalities involving 11q13-14 were studied, to determine if this abnormality was closely associated with a specific sub-type of B-NHL. A t(11;14)(q13;q32) was found in 11 cases of intermediately differentiated lymphocytic lymphoma (IDLL). A breakpoint in the major translocation cluster of the BCL-1 locus was found in six of these cases. These patients were male with lymphomatous involvement of the bone marrow, marked splenomegaly and frequently had mucosa associated lymphoid tissue involvement. One patient with IDLL had a t(8;11)(p21;q13) and a rearranged BCL-1 locus, suggesting that this may be a variant of t(11;14)(q13;q32). Diagnoses of IDLL, chronic lymphocytic leukaemia, lymphoplasmacytic lymphoma and monocytoid B cell lymphoma were made in all but one of the remaining cases. These cases had either a translocation involving 11q13-14 and various partner chromosomes or an 11q13 deletion. This study demonstrates that 11q abnormalities occur mainly in a group of low-grade B-NHL of non follicle centre cell lineage.  相似文献   
44.
Metabolic Brain Disease - In Part I of this Review we evaluated the scientific evidence for a Metabolic Model of multiple sclerosis (MS). Part II outlines the implementation of an adaptive...  相似文献   
45.
BACKGROUND & AIMS: In the absence of pathognomonic markers for Crohn's disease (CD) and ulcerative colitis (UC), the diagnosis of inflammatory bowel disease depends on a compendium of clinical, radiographic, endoscopic, and histologic criteria that bears imperfect specificity to the individual disorders. In 10% of cases of colitis, no differentiation can be made between CD and UC; these patients are diagnosed with indeterminate colitis (IC). We evaluated the value of anti-Saccharomyces cerevisiae antibodies (ASCA) and perinuclear antineutrophil cytoplasmic antibodies (pANCA) to increase diagnostic accuracy in categorizing IC. METHODS: Since 1996, 97 patients with IC from 3 centers (Leuven, Lille, and Vienna) were enrolled, analyzed for pANCA and ASCA, and followed up prospectively. RESULTS: A definitive diagnosis has been reached for 31 of 97 patients (32%). In these patients, ASCA+/pANCA- correlated with CD in 8 of 10 patients, whereas ASCA-/pANCA+ correlated with UC in 7 of 11 patients. The remaining 4 cases became CD, clinically behaving as UC-like CD. Almost half of the patients (47 of 97 [48.5%]) were negative for ASCA and pANCA, and 40 remain diagnosed with IC to date. Only 7 seronegative cases (14.9%) became CD or UC compared with 48% (24 of 50) of seropositive patients (P < 0.001). CONCLUSIONS: Results so far show that ASCA+/pANCA- predicts CD in 80% of patients with IC and ASCA-/pANCA+ predicts UC in 63.6%. Interestingly, 48.5% of patients do not show antibodies against ASCA or pANCA. Most of these patients remain diagnosed with IC during their further clinical course, perhaps reflecting a distinct clinicoserological entity.  相似文献   
46.
OBJECTIVE: To describe the incidence, cause, and course of anaemia in rheumatoid arthritis (RA). METHODS: Medical records of 225 patients who received a diagnosis of RA between 1990 and 1992 were reviewed longitudinally for mention of anaemia. Anaemia was classified as anaemia of chronic disease if ferritin concentrations reflected adequate body iron stores. Among iron depleted anaemic patients, iron deficiency anaemia was identified using the response to iron supplementation. RESULTS: Anaemia developed in 64% of the patients, mostly within 18 months of follow up, but disappeared again in 54% of those patients. The prevalence of anaemia varied from 39% to 53% throughout follow up. Iron depletion was found in 38% of anaemic patients; 40% of them did not recover from their anaemia after iron supplementation and were classified as having anaemia of chronic disease. Anaemia of chronic disease thus caused 77% and iron deficiency anaemia 23% of observed anaemia. Recovery from anaemia occurred in 42% of the patients with anaemia of chronic disease and in 72% of iron depleted patients after iron supplementation. Anaemic patients, particularly those with anaemia of chronic disease, had a significantly greater number of the American College of Rheumatism criteria for RA, significantly more erosive joint damage, and significantly increased concentrations of serum rheumatoid factor than patients without anaemia. CONCLUSION: Anaemia appeared as a frequent and dynamic manifestation. Recovery and recurrence of anaemia was observed throughout follow up, leading to a longstanding and relatively high prevalence of the condition. Iron deficiency was diagnosed frequently and follow up revealed a considerable overlap with anaemia of chronic disease, making this the most important cause of anaemia in RA. Recovery from anaemia occurred more frequently in iron depleted anaemic patients than in those with anaemia of chronic disease. Anaemic patients, particularly those with anaemia of chronic disease, seemed to have a more serious course of their RA compared with non-anaemic patients.  相似文献   
47.
The efficacy and safety of intramuscular artemotil (ARTECEF) was compared to intravenous quinine in African children with cerebral malaria. This prospective block randomized open-label study was conducted at two centers in Zambia. Subjects were children aged 0 to 10 years of age with cerebral malaria and a Blantyre Coma Score of 2 or less. Ninety two children were studied; 48 received artemotil and 44 quinine. No significant differences in survival, coma resolution time, neurologic sequelae, parasite clearance time, and fever resolution time were seen between the two regimens. Rates for negative malaria smears one month after therapy were similar in both groups. Artemotil was a well-tolerated drug in the 48 patients in this study. It appears to be at least therapeutically equivalent to quinine for the treatment of pediatric cerebral malaria. It has the advantage of being able to be given intramuscularly once daily for only five days.  相似文献   
48.
Most efforts to characterize sequence variation of HIV isolates has been directed toward the structural envelope gene. Few studies have evaluated the sequence variability of auxiliary genes such as nef. In this study 41 new HIV-1 strains, representing the majority of the described envelope subtypes of HIV-1 (A to H), were genetically characterized in the nef region. Phylogenetic analysis showed that 34 strains could be classified in the same subtype in nef and env, and 7 (19%) of the 41 new viruses were recombinants. For two of the seven strains, recombination occurred upstream of the nef gene, whereas for five of the seven strains recombination occurred within the nef gene with a crossover close to the 5' end of the LTR (long terminal repeat). The low intersubtype distance between subtype B and D in the nef gene confirms previous observations in the pol, env, and gag genes, which suggest a common ancestor for these subtypes. The majority of all the previously described functional domains in the nef gene were relatively conserved among the different subtypes, with only minor differences being observed. The myristoylation signal among the different subtypes, with only minor differences being observed. The myristoylation signal was less conserved for subtype C, with one or more amino acid changes being observed at positions 3, 4, and 5. The highly conserved acidic region (positions 62 to 65), critical for the enhancement of viral synthesis with an increased virus growth rate, was less conserved among the subtype G strains from our study. At least three epitopic regions of the nef gene have been defined and each can be recognized by CTLs under a variety of HLA restrictions; all were also relatively well conserved between the different genetic subtypes. Despite the relatively important genetic variation in nef sequences obtained among the different genetic subtypes, functional domains and CTL epitopes were relatively well conserved. In vitro and/or in vivo studies are necessary to study the relevance of the observed differences.  相似文献   
49.
Noninvasive assessment and monitoring of the pulmonary circulation.   总被引:3,自引:0,他引:3  
In pulmonary vascular disease, changes in the pulmonary vascular bed will lead to altered pulmonary haemodynamics. This review describes the application of several physiological principles to measure these changes noninvasively by means of novel techniques. Flow characteristics of blood through the pulmonary vascular bed alter in pulmonary vascular disease. Recent developments in magnetic resonance imaging and computed tomography make it possible to visualise and quantify these abnormal flow patterns. Information regarding pulmonary perfusion can also be obtained by measuring the electrical impedance changes in the lung by electrical impedance tomography. A more indirect approach to measure the pulmonary blood flow is the measurement of the absorption of acetylene, a perfusion limited gas. Information on the pulmonary vascular bed can also be obtained by the measurement of exhaled products of the pulmonary vascular endothelium, such as nitric oxide. Although all the techniques described offer new ways to diagnose or monitor pulmonary vascular disease, clinical data on these techniques are limited. Further improvement and evaluation of the clinical value of these techniques are therefore obligatory before they can be used in clinical practice.  相似文献   
50.
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