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91.
92.
Schistosomiasis: an unusual cause of tubal infertility   总被引:3,自引:0,他引:3  
A case report of a Nigerian woman having an unusual cause oftubal infertility is presented. On histological examinationof the Fallopian tube, ova of Schistosoma haematobium enclosingliving miracidia were found in the smooth muscle layer of theFallopian tube and its mesosalpinx. Mechanisms of tubal involvementare analysed. The case indicates the need to consider schisto-somiasisas a possible aetiological factor in patients with tubal infertilitycoming from areas where the disease is endemic.  相似文献   
93.
Performance-Based Incentive Compensation (PBIC) plans currently prevail throughout industry and have repeatedly demonstrated effectiveness as powerful motivational tools for attracting and retaining top talent, enhancing key indicators, increasing employee productivity, and, ultimately, enhancing mission-based parameters. The University of Arkansas for Medical Sciences (UAMS) College of Medicine introduced its PBIC plan to further the transition of the college to a high-performing academic and clinical enterprise. A forward-thinking compensation plan was progressively implemented during a three-year period.After the introduction of an aggressive five-year vision plan in 2002, the college introduced a PBIC plan designed to ensure the retention and recruitment of high-quality faculty through the use of uncapped salaries that reflect each faculty member's clinical, research, and education duties. The PBIC plan was introduced with broad, schoolwide principles adaptable to each department and purposely flexible to allow for tailor-made algorithms to fit the specific approaches required by individual departments.As of July 2006, the college had begun to reap a variety of short-term benefits from Phase I of its PBIC program, including increases in revenue and faculty salaries, and increased faculty morale and satisfaction.Successful implementation of a PBIC plan depends on a host of factors, including the development of a process for evaluating performance that is considered fair and reliable to the entire faculty. The college has become more efficient and effective by adopting such a program, which has helped it to increase overall productivity. The PBIC program continues to challenge our faculty members to attain their highest potential while rewarding them accordingly.  相似文献   
94.
Whether persons with multiple chemical sensitivity syndrome (MCS) have immunological abnormalities is unknown. To assess the reliability of selected immunological tests that have been hypothesized to be associated with MCS, replicate blood samples from 19 healthy volunteers, 15 persons diagnosed with MCS, and 11 persons diagnosed with autoimmune disease were analyzed in five laboratories for expression of four T-cell surface activation markers (CD25, CD26, CD38, and HLA-DR) and in four laboratories for autoantibodies (to smooth muscle, thyroid antigens, and myelin). For T-cell activation markers, the intralaboratory reproducibility was very good, with 90% of the replicates analyzed in the same laboratory differing by ≤3%. Interlaboratory differences were statistically significant for all T-cell subsets except CD4+ cells, ranging from minor to eightfold for CD25+ subsets. Within laboratories, the date of analysis was significantly associated with the values for all cellular activation markers. Although reproducibility of autoantibodies could not be precisely assessed due to the rarity of abnormal results, there were inconsistencies across laboratories. The effect of shipping on all measurements, while sometimes statistically significant, was very small. These results support the reliability of fresh and shipped samples for detecting large (but perhaps not small) differences between groups of donors in the T-cell subsets tested. When comparing markers that are not well standardized, it may be important to distribute samples from different study groups evenly over time.  相似文献   
95.
Zusammenfassung Das Variolavirus konnte aus menschlichem Pustel- und Krustenmaterial intraperitoneal in infantilen Mäusen angezüchtet und in fortlaufenden Passagen weitergeführt werden. Es blieb innerhalb von 20 Passagen in bezug auf seine biologischen Eigenschaften im Hühnerembryo stabil. Eintägige Mäuse waren empfänglicher als dreitägige Tiere. Innerhalb verschiedener Mäusefamilien bestand eine unterschiedliche Resistenz gegenüber der Variolainfektion. Bei resistenteren Tieren vermehrte sich das Virus, ohne klinische Erscheinungen zu verursachen.Ein besonders bevorzugtes Organ für die Vermehrung des Variolavirus war die Lunge.Bei infizierten, klinisch aber gesunden Mäusen ließ sich aus den Lungen der Tiere in einem Zeitraum von 45 Tagen p. i. infektiöses Variolavirus züchten.  相似文献   
96.
The common γ chain (γc) forms a critical component of the receptors for interleukins (IL)-2, IL-4, IL-7, IL-9, and IL-15. We analyzed γc-deficient mice to define a role for γc signaling in the development and function of the macrophage lineage. No major differences in absolute cell numbers, cell surface phenotype, or in vitro function of γ?c compared to γ+c macrophages were observed. We therefore conclude that signaling through the γc chain is not essential for the differentiation of mouse macrophages. Although B and T cells require γc for IL-4 responses, IL-4 up-regulated major histocompatibility class II molecules and inhibited nitric oxide production from γ?c macrophages following stimulation with lipopolysaccharide and interferon-γ. γ?c macrophages could also respond to IL-13, consistent with the model of a type II IL-4 receptor α/IL-13R which can function in the absence of γc. Both IL-4 and IL-13 responses could be completely inhibited with the mouse IL-4 antagonist QY, suggesting that all of the observed IL-13 responses pass through the type II receptor, making it the primary signaling receptor complex for IL-13 in mouse macrophages.  相似文献   
97.
Further evidence for a separate MLC-locus   总被引:2,自引:0,他引:2  
  相似文献   
98.
Genetically altering the disease vector status of insects using recombinant DNA technologies is being considered as an alternative to eradication efforts. Manipulating the endogenous immune response of mosquitoes such as the temporal and special expression of antimicrobial peptides like cecropin may result in a refractory phenotype. Using transgenic technology a unique pattern of expression of cecropin A (cecA) in Anopheles gambiae was created such that cecA was expressed beginning 24 h after a blood meal in the posterior midgut. Two independent lines of transgenic An. gambiae were created using a piggyBac gene vector containing the An. gambiae cecA cDNA under the regulatory control of the Aedes aegypti carboxypeptidase promoter. Infection with Plasmodium berghei resulted in a 60% reduction in the number of oocysts in transgenic mosquitoes compared with nontransgenic mosquitoes. Manipulating the innate immune system of mosquitoes can negatively affect their capacity to serve as hosts for the development of disease-causing microbes.  相似文献   
99.
Vaccine development and our understanding of the pathology of bovine tuberculosis in cattle would be greatly facilitated by definition of the immunological correlates of protection and/or pathology. In this study we analyzed humoral immune responses in Mycobacterium bovis BCG-vaccinated and control cattle (in particular, the relationship between the intradermal comparative tuberculin skin test and serum immunoglobulin G [IgG] responses) against a range of mycobacterial antigens (MPB59, MPB64, MPB70, MPB83, ESAT-6, CFP-10, Acr1, and PstS-1) by multiantigen print immunoassay and conventional enzyme-linked immunosorbent assay. Following M. bovis infection, the comparative tuberculin skin test strongly boosted IgG, IgG1, and IgG2 antibody responses, particularly against MPB83 and MPB70, in unvaccinated cattle but failed to boost these responses, or did so only weakly, in BCG-vaccinated calves. In addition, the skin test-induced increases in MPB83-specific IgG responses correlated positively with bacterial loads and ESAT-6-induced in vitro gamma interferon responses. In conclusion, both the negative correlation of skin test-enhanced MPB83-specific antibody responses with BCG-induced protection and their positive correlation with bacterial loads can serve as useful markers for vaccine efficacy after challenge.  相似文献   
100.
Previous studies have suggested that the primary site of action of purified staphylococcal alpha toxin is the cell membrane. Scanning and transmission electron microscopy studies were undertaken, therefore, to define toxin-induced alterations in the surface morphology of rabbit and human red blood cells. During the prelytic lag phase, scanning electron microscopy revealed multiple discrete blisters on the surface of rabbit red blood cells; during hemolysis, cellular collapse and ghosts were seen, but most striking was the separation of large fragments of cell membrane from red blood cell surfaces. In contrast, alterations in less sensitive human red blood cells were limited to occasional fingerlike protrusions during the period of accelerated lysis. Transmission electron microscopy substantiated these changes. These studies have provided further evidence that the cell membrane is the primary site of action of staphylococcal alpha toxin.  相似文献   
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