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991.
HIV合并结核感染的流行病学特征和相关影响因素   总被引:1,自引:0,他引:1  
目的研究人类免疫缺陷病毒(humam immunodenciency virus,HIV)感染者中合并结核(tuberculosis,TB)感染的流行病学特征和相关影响因素。方法对1139例HIV感染者或艾滋病(AIDS)病人,用统一的调查表了解其流行病学一般情况,行痰涂片、X光胸片检查、PPD皮试、TB抗体以及血沉等检测,部分病人做了痰培养或病理检查。对1023例结核病人进行HIV抗体检测,用SPSS软件对不同因素对HIV合并TB感染或TB合并HIV感染的影响情况进行相关性分析。结果本组HIV合并TB的感染率为25.20%;静脉吸毒传播的HIV感染者合并的TB发病率明显高于性传播的HIV感染者(33.62%vs18.61%,)(χ2=31.63,P〈0.01),CD4^+T细胞计数≤200个/μl的AIDS病人其TB发病率明显高于其它组(35.93%VS23.55%,χ2=11.42,P〈0.01;35.93%vs21.80%,χ2=42.37,P〈0.01)。住院TB患者中HIV抗体的检出率为1.56%。不同年龄组和不同职业的结核患者其抗HIV检出率差异无统计学意义(P〉0.05);有吸烟史或其它慢性肺部疾病史的结核患者中HIV的检出率比无该类病史的患者更高。结论本组HIV合并TB感染率25.20%,静脉吸毒传播者和CD4^+T细胞〈200个/μl的HIV—AIDS合并结核感染的发病率较高。有吸烟史或肺部感染史的结核患者,HIV抗体的检出率较高。  相似文献   
992.

Background

Detailed knowledge of the distribution and distal course of periprostatic nerves is essential to improve functional outcomes (erection and continence) after radical prostatectomy (RP).

Objective

To describe the location of nerve fibres within neurovascular bundles (NVBs) and around the prostate by three-dimensional (3D) computer-assisted anatomic dissection (CAAD) in human foetuses and adult cadavers.

Design, setting, and participants

Serial transverse sections of the pelvic portion were performed in seven human male foetuses and four male adult cadavers. Sections were treated by histologic coloration and neuronal immunolabelling of S100 protein. 3D pelvic reconstruction was achieved with digitised serial sections and WinSurf software.

Measurements

We evaluated the distribution of nerve fibres within the NVB qualitatively. The distribution of periprostatic nerves was also evaluated quantitatively in the adult specimens.

Results and limitations

Periprostatic nerve fibres were dispersed around the prostate on all sides with a significant percentage of these fibres present in the anterior and anterolateral sectors. At the prostate apex and the urethral levels, the NVBs have two divisions: cavernous nerves (CNs) and corpus spongiosum nerves (CSNs). The CNs were a continuation of the anterior and anterolateral fibres around the apex of the prostate, travelling towards the corpora cavernosa. The CSNs were a continuation of the posterolateral NVBs, and they eventually reached the corpus spongiosum. The limitations of this study were the small number of specimens available and the lack of functional information.

Conclusions

The anterolateral position of CNs at the apex of the prostate and the autonomic innervation towards the corpus spongiosum via CSNs indicate possible ways to minimise the effect of prostate surgery on sexual function. The ideal dissection plane should probably include the preservation of the anterolateral tissues and fascias to avoid CN lesions. Anatomic knowledge gained from CAAD pertains directly to proper surgical technique and subsequent recovery of erectile function after RP.  相似文献   
993.
The aim of this study is to define criteria for accurate representation of the thyroid in human models used to represent external beam radiotherapy (EBRT) patients and evaluate the relationship between the volume of this organ and clinical and anthropometric characteristics. From CT images, we segmented the thyroid gland and calculated its volume for a population of 188 EBRT patients of both sexes, with ages ranging from 1 to 89 years. To evaluate uncertainties linked to measured volumes, experimental studies on the Livermore anthropomorphic phantom were performed. For our population of EBRT patients, we observed that in children, thyroid volume increased rapidly with age, from about 3 cm(3) at 2 years to about 16 cm(3) at 20. In adults, the mean thyroid gland volume was 23.5 ± 9 cm(3) for males and 17.5 ± 8 cm(3) for females. According to anthropometric parameters, the best fit for children was obtained by modeling the log of thyroid volume as a linear function of body surface area (BSA) (p < 0.0001) and age (p = 0.04) and for adults, as a linear function of BSA (p < 0.0001) and gender (p = 0.01). This work enabled us to demonstrate that BSA was the best indicator of thyroid volume for both males and females. These results should be taken into account when modeling the volume of the thyroid in human models used to represent EBRT patients for dosimetry in retrospective studies of the relationship between the estimated dose to the thyroid and long-term follow-up data on EBRT patients.  相似文献   
994.
Although signal pathways triggered via the CD40 molecule are well characterized, those induced via CD154 are less known. This study demonstrates that engagement of CD154 in Jurkat D1.1 cells with soluble CD40 leads to PKC α and δ activation, calcium mobilization, and phosphorylation of the Map kinases ERK1/2 and p38. Such response is accompanied by significant recruitment of CD154 into lipid rafts. Disruption of lipid rafts integrity with nystatin or methyl β‐cyclodextrin abrogated PKCα PKCδ and p38 phosphorylation, but had no effect on ERK1/2 phosphorylation. Inhibition of PKC activation completely abolished p38 phosphorylation but had no effect on ERK1/2 phosphorylation, suggesting that localization of CD154 within lipid rafts is an absolute requirement for CD154‐induced PKCα‐ and PKCδ‐dependent p38 phosphorylation. Furthermore, CD154 acts as co‐stimulator for the production of IL‐2 in an APC‐superantigen‐T‐cell activation model. The results obtained demonstrate for the first time, that lipid rafts are of immunological relevance for CD154‐triggered signals, and reinforce the importance of CD154 in T‐cell activation.  相似文献   
995.
996.
During the rainy season 2003, an entomological survey was undertaken in the Sahelian bioclimatic zone of the Ferlo area in northern Senegal, in order to evaluate the degree of interaction between Rift valley fever (RVF) virus vectors and domestic animals and to determine the role of natural vertebrate hosts in the transmission and maintenance cycle. The study of vector-host contact was carried out under bed net traps using man, cow, sheep, chicken as bait whereas the RVFV vectors-vertebrate host interactions were studied through the analysis by an ELISA technique of the origin of the blood meals from naturally engorged females collected by aspiration. Blood meals sources were determined using a set of eight antibodies. Overall, the different known RVFV vectors (Culex poicilipes, Aedes vexans and Aedes ochraceus) were opportunistic although the bovine-baited net was, as far the more effective trap with 53.6% of collected mosquitoes. It was followed by the sheep-baited net (16.7%), man-baited net (12.6%) and chicken-baited net (11.6%). The more effectiveness of the bovine-baited net confirms the degree of implication of this host in RVF epidemiology. The study of vector-hosts interactions in nature showed that among the 1,112 mosquito blood meals tested, 701 were identified of which 693 were from Aedes vexans. The percentage of non-reacting blood meal was 36.7% whereas 16.9 % of the blood meals were taken at least on two vertebrate hosts. Overall, 53.2% of the blood meals from Ae. vexans were taken on equine, 18.6% on bovines, 7.1% on sheep and 0.6% on human. No blood meal was taken on rodent. The greatest diversity was observed in August. These host feedings patterns show that although equine is known to play a minor role in RVF epidemiology a thorough attention should be made to this host with regard to the percentage of blood meals taken in this host. The low percentage of blood meals taken on human could probably explain the low human infection rate observed up to now in Senegal. With the high percentage of non-reacting blood meals, our results also underline the necessity of an improvement of ELISA techniques and the use of more reliable tools as molecular markers for an exhaustive identification of vertebrates hosts involved in RVF epidemiological cycle.  相似文献   
997.
Monocyte dysfunction in filarial infection has been proposed as one mechanism underlying the diminished antigen-specific T-cell response seen in patent lymphatic filariasis. Cytokine/chemokine production and gene expression in monocytes from filaria-infected patients and uninfected healthy donors were assessed unstimulated and in response to stimulation with Staphylococcus aureus Cowan I bacteria plus gamma interferon both before and 8 months following treatment. Monocytes from filaria-infected individuals were studded with intracellular microfilarial antigens. Furthermore, monocytes from these individuals were less capable of producing interleukin-8 (IL-8), Exodus II, MIP-1alpha, MIP-1beta, and IL-1alpha and preferentially expressed genes involved in apoptosis and adhesion compared with monocytes from uninfected donors. Eight months following treatment with a single dose of ivermectin-albendazole, some of these defects were reversed, with monocyte production of IL-8, IL-1alpha, MIP-1alpha, and IL-10 being comparable to that seen in the uninfected controls. In addition, a marked increase in mRNA expression of genes associated with protein metabolism, particularly heat shock proteins, was seen compared with pretreatment expression. These data suggest that the function and gene expression of monocytes in filaria-infected patients are altered but that this dysfunction is partially reversible following antifilarial treatment.  相似文献   
998.
999.
1000.
Peste des petits ruminants (PPR) is an important economically transboundary disease of sheep and goats caused by a virus which belongs to the genus Morbillivirus. This genus, in the family Paramyxoviridae, also includes the measles virus (MV), canine distemper virus (CDV), rinderpest virus (RPV), and marine mammal viruses. One of the main features of these viruses is the severe transient lymphopaenia and immunosuppression they induce in their respective hosts, thereby favouring secondary bacterial and parasitic infections. This lymphopaenia is probably accounted for by the fact that lymphoid cells are the main targets of the morbilliviruses. In early 2000, it was demonstrated that a transmembrane glycoprotein of the immunoglobulin superfamily which is present on the surface of lymphoid cells, the signalling lymphocyte activation molecule (SLAM), is used as cellular receptor by MV, CDV and RPV. Wild-type strains of these viruses can be isolated and propagated efficiently in non-lymphoid cells expressing this protein. The present study has demonstrated that monkey CV1 cells expressing goat SLAM are also highly efficient for isolating PPRV from pathological samples. This finding suggests that SLAM, as is in the case for MV, CDV and RPV, is also a receptor for PPRV.  相似文献   
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