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61.
The availability of a marker that could predict the course of disease progression in HIV-infected individuals would be of considerable relevance during the asymptomatic stage in order to undertake timely prophylactic measures. A prospective study was undertaken in a group of 42 children suffering from thalassemia major with HIV-1 infection to assess the status of immune parameters, such as peripheral CD4+ T lymphocyte (CD4+ cell) percentage, delayed type of hypersensitivity (DTH) response to recall antigens, detection rate and levels of p24 antigen, and levels of beta-2 microglobulin and cytokines in serum. All were assessed at an interval of 2 years during the asymptomatic period, (baseline and follow-up assessments) in relation to the development of AIDS defining illness within a follow-up period of 3 years. No difference could be observed in the mean CD4+ cell percentage at baseline between those who progressed subsequently to develop AIDS within the follow-up period (progressors) and those who did not (non-progressors). However, at the point of follow-up assessment the progressor group showed significantly lower CD4+ cell percentage compared to the non-progressor group (33 +/- 4.9 vs. 22 +/- 5.6; p < 0.05), although in the progressor group there was no correlation of the baseline and follow-up CD4+ cell percentage with the duration of the AIDS-free interval. However, in the progressor group there was a strong negative correlation between the rate of decline in CD4+ cell percentage and subsequent duration of the AIDS-free interval (r = -0.859). Analysis of additional immune parameters at baseline revealed that the progressor group, despite having CD4+ cell values comparable to non-progressors, showed impaired DTH response (number and total induration of positive responses being 2.0 +/- 1.23 and 6.2 +/- 1.4 in the former group vs. 3.2 +/- 0.76 and 12.6 +/- 3.80 in the later group; p < 0.05 for both the parameters), and elevated levels (mg/l) of serum beta-2 microglobulin (2.92 +/- 0.89 vs. 1.38 +/- 0.43; p < 0.05). The serum cytokine profile at baseline in the progressor group showed a T helper type-2 (Th2) dominant pattern, i.e. elevation of interleukin-4 (IL-4) and interleukin-10 (IL-10) levels with decreased levels of interleukin-2 (IL-2) and gamma interferon (gamma-IFN) compared to the non-progressor group that showed a T helper type-1 (Th1) dominant profile, i.e., elevation of IL-1 and gamma-IFN level with decreased levels of IL-4 and IL-10 (p < 0.05 for all four cytokines). The present study points out that rate of decline rather than single point of assessment of CD4+ cell values is a more reliable predictor for disease progression in HIV-1 infected children. In addition, parameters such as DTH response, serum levels of beta-2 microglobulin and serum cytokine profile, may provide valuable predictors of subsequent fall in CD4+ cell value.  相似文献   
62.
目的:制备用于白内障超声乳化训练的活体白内障动物模型。 方法:狗在全身麻醉下用26号带有斜面的针刺破左眼的晶状体前囊,制备白内障模型,形成白内障后,行超声乳化手术。 结果:眼部检查显示晶状体后部皮质混浊开始于穿刺术后5~7d,并于术后75d白内障全部形成,在所有的白内障形成的眼上行超声乳化手术,并植入人工晶状体,所有的狗均恢复了视力。 结论:考虑到无经验的眼科医生在行白内障超声乳化手术的初始阶段引起的巨大损失,我们认为这个活的动物模型明显优于目前用于训练超声乳化手术的尸体眼。  相似文献   
63.
Urinary tract injury in pelvic surgery   总被引:4,自引:0,他引:4  
  相似文献   
64.
Role of heparan sulfate in human parainfluenza virus type 3 infection   总被引:6,自引:0,他引:6  
Bose S  Banerjee AK 《Virology》2002,298(1):73-83
Our current studies have demonstrated that human parainfluenza virus type 3 (HPIV-3) utilizes heparan sulfate (HS) for its efficient cellular entry. HPIV-3 interacted with HS-agarose in vitro and the cellular entry and infection of HPIV-3 were reduced following (a) infection of human epithelial lung A549 cells with HPIV-3 pre-incubated with soluble HS; (b) treatment of A549 cells with heparinase to remove cell surface HS and sodium chlorate (NaClO(3)), a potent inhibitor of proteoglycan sulfation; and (c) infection of HS-deficient mutant CHO cell lines. However, in each instance, complete inhibition of HPIV-3 entry did not occur, suggesting the presence of additional nonproteoglycan cell surface molecule(s) that is required for HPIV-3 entry. Thus the cell surface HS appears to play an important role in efficient cellular entry of HPIV-3.  相似文献   
65.
This study investigated the morphological features of the soleus motoneuron pool in rats with chronic (4 months), midthoracic (T8) contusions of moderate severity. Motoneurons were retrogradely labeled using unconjugated cholera toxin B (CTB) subunit solution injected directly into the soleus muscle of 10 contused and 6 age- and sex-matched, normal controls. Morphometric studies compared somal area, perimeter, diameter, dendritic length, and size distribution of labeled cells in normal and postcontusion animals. In normal animals, motoneurons with a mean of 110.4 +/- 5.2 were labeled on the toxin-injected side of the cord (left). By comparison, labeled cells with a mean of 93.0 +/- 8.4 (a 16% decrease, P = 0.006) were observed in the chronic spinal-injured animals. A significantly smaller frequency of very small (area, approximately 100 microm2) and medium (area, 545-914 microm2) neurons, and a significantly higher frequency of larger (area, >914 microm2) neurons was observed in the labeled soleus motoneuron pools of injured animals compared with the normal controls. Dendritic bundles in the contused animals were composed of thicker dendrites, were arranged in more closely aggregated bundles, and were organized in a longitudinal axis (rostrocaudal axis). Changes in soleus motoneuron dendritic morphology also included significant decrease of total number of dendrites, increased staining, hypertrophy of primary dendrites, and significant decreased primary, secondary, and tertiary branching. The changes in size distribution and dendritic morphology in the postcontusion animals possibly resulted from cell loss and transformation of medium cells to larger cells and/or injury-associated failure of medium cells to transport the immunolabel.  相似文献   
66.
We have analysed the results of 246 cases of distal femoral tumours treated by resection and prosthetic replacement between 1988 and 2002. Patient ages ranged from 6–67 years averaging 24 years; 133 were males. The most common tumour was osteosarcoma (67% of patients). The follow-up ranged from 2 to 14 years. Stage II tumours were seen in 72% of patients. The technique of sleeve resection of the quadriceps musculature was followed to achieve local clearance of the tumour. The prosthesis used was a rotating hinge custom mega-prosthesis manufactured locally. The functional result achieved was excellent or good in 87%; 86% of the patients had no evidence of disease, and 13% had died. The 10-year patient survival was 76.9%. Periprosthetic fracture and infection were the most common complications.
Résumé Nous avons analysé les résultats de 246 cas de tumeurs fémorales distales traitées par résection et remplacement prothétique entre 1988 et 2002. Lâges des malades sétendait de 6 à 67 ans avec une moyenne de 24 ans. Cent trente trois étaient des hommes. La tumeur la plus fréquente était lostéosarcome (67% des malades). Le suivi était de 2 à 14 années. Des tumeurs de stade II étaient présentes chez 72% des malades. La technique de résection a été conduite pour faire une ablation complète de la tumeur. La prothèse qui a été utilisée était une méga prothèse à charnière rotatoire fabriqué localement. Le résultat fonctionnel obtenu était excellent ou bon dans 87%. Quatre-vingt-six pourcent des malades navait pas dévidence de maladie et 13% étaient morts. La survie à dix ans était de 76,9%. Les fractures périprothétiques et linfection étaient les complications les plus fréquentes.
  相似文献   
67.
Results from randomized, placebo-controlled clinical trials have demonstrated that escitalopram is effective and well tolerated in the treatment of depression and anxiety disorders. Such trials typically employ stringent inclusion criteria that may limit the generalizability of findings to the broader population of patients treated in psychiatric and primary care practices. The objective of the current trial was to assess the effect of escitalopram treatment on depressed outpatients in naturalistic settings. This 8-week open-label trial enrolled 5,453 outpatients aged > or = 18 years with nonpsychotic major depressive disorder from primary care (n = 2,591), psychiatric (n = 2,289), and other specialty (n = 573) practices. Escitalopram was initiated at 10 mg/day, and dose could be increased to a maximum of 20 mg/day. Efficacy measures included the Clinical Global Impressions of Improvement (CGI-I) scale, Patient Global Evaluation (PGE) scale, Hospital Anxiety and Depression Scale, Sheehan Disability Scale, and 12-Item Short Form Health Survey. Overall, 76% of patients completed 8 weeks of treatment. The mean dose of escitalopram was 11.6 mg/day. At endpoint, response rates (defined as a score < or = 2 on the CGI-I or PGE) were 68% on the clinician-assessed CGI-I and 66% on the PGE. Improvement was not related to age or response to prior antidepressant treatment. Overall, 9% of patients discontinued due to adverse events. Escitalopram treatment was well tolerated and associated with robust response rates in a broadly representative population of depressed outpatients.  相似文献   
68.
The role of art in the encounter with trauma and destructiveness is comparatively studied in the works of Frida Kahlo and Francis Bacon as examples of a direct and a more indirect way of dealing with such experiences. A creative product may function intrapsychically as a kind of messenger between dissociated self-states and consciousness, and it may also serve as a witnessing presence in a self-supporting and self-constituting way. Artistic work may thus be used by the artist for an expressive as well as for a protective purpose, as a means of sympathetic participation in painful experience, or as a medium for a view from the outside. The act itself of finding and of making expressive forms at the time of traumatic experience is a remarkable assertion of the human capability to synthesize and to counteract fragmenting dissociative processes.  相似文献   
69.
As high grade PIN is commonly associated with concomitant cancer, current literature recommends re-biopsy of patients with high grade PIN. This paper describes the prevalence of high grade prostatic intra-epithelial neoplasia (PIN) from three independent clinical settings, reported by a single pathologist (MCP). High grade PIN was diagnosed in biopsies from 131 of the 1205 (11%) of patients in whom cancer was suspected in hospital practice, 42 of the 202 (20%) asymptomatic men screened for prostate cancer and 29 of the 118 (25%) patients presenting with prostatism in a case finding study. Re-biopsy on this scale has major clinical and cost implications. However, from a literature review, there is evidence to suggest that the risk of concomitant cancer with high grade PIN may be stratified according to serum PSA. This opinion should be tested prospectively.  相似文献   
70.
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