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991.
992.
In late January 1985, a measles outbreak occurred at a community hospital in Columbia county, Florida. The outbreak spread throughout the county and to two neighboring counties (Alachua and Marion), resulting in 79 cases with a 29% hospitalization rate. Hospitals represented the site with the highest frequency of transmission. At the Alachua county hospitals, where strict respiratory isolation measures were taken, no secondary cases occurred among hospitalized patients. Two independent risk factors existed for hospitalization: measles exposure in a hospital setting (P less than 0.05) and nonvaccination (P less than 0.001). Of the total measles cases, 24% were under the age of 16 months and 47% of those aged 16 months or older had a history of appropriate vaccination. Columbia county, which experienced 86% of the cases, had a 5% frequency of unvaccinated students compared to 0.6% frequency at Alachua (P less than 0.001) where only 10% of the cases occurred. This outbreak demonstrates the role of uncontrolled nosocomial transmission of measles in the propagation of a community outbreak.  相似文献   
993.
Increasing evidence supports a role for HA as a neurotransmitter and neuromodulator in various brain functions, including emotion, cognition, and feeding. The recent cloning of the histamine H3 receptor allowed for the subsequent cloning of a variety of H3 receptor isoforms from different species as well as the H4 receptor. As a result a wide variety of H3-receptor isoforms are now known that display differential brain expression patterns and signalling properties. These recent discoveries are discussed in view of the growing interest of the H3 receptor as a target for the development of potential therapeutics.  相似文献   
994.
Background: An outbreak of typhoid fever among school children of a school in military station in central India is reported here. It comprises of 98 students out of which 87 students were from one school.  相似文献   
995.
Pentastarch may cause fewer effects on coagulation than hetastarch   总被引:9,自引:0,他引:9  
Hetastarch, the currently marketed preparation of hydroxyethyl starch, affects coagulation by prolonging partial thromboplastin, prothrombin, and bleeding times; by lowering clotting proteins such as fibrinogen via hemodilution; by lowering clotting factor VIII (coagulant, von Willebrand antigen, and von Willebrand activity) to a greater degree than can be explained simply by hemodilution (i.e., presumably factor VIII affected by both hemodilutional plus additional, independent effects); and, finally, by shortening thrombin, reptilase, and urokinase-activated clot lysis times. Pentastarch, a new analog of hetastarch, was found to exert lesser effects on blood coagulation, despite its greater hemodiluting properties. When compared with hetastarch, pentastarch had little effect on factor VIII (except that due to hemodilution), shortened thrombin times to a significantly lesser degree, exerted no effect on the urokinase-activated clot lysis time, and did not prolong the bleeding time. Even when plasma hydroxyethyl starch levels were similar, pentastarch seemed to alter the results of coagulation assays to lesser degree than did hetastarch, which suggests the possibility of greater safety. Therefore, pentastarch may be a desirable drug, not only for leukapheresis, but also for plasma volume expansion in trauma and surgical patients who often have additional hemostatic abnormalities that place them at increased risk of hemorrhage.  相似文献   
996.
BACKGROUND: The most common human immunodeficiency virus (HIV)-related cause of death in persons with transfusion-acquired (TA) AIDS has been Pneumocystis carinii pneumonia (PCP). While better treatment for PCP accounts for improved survival among HIV-infected homosexual or bisexual men, the extent to which others have benefitted from these developments is unknown. STUDY DESIGN AND METHODS: Patterns of PCP care among persons with TA-AIDS, intravenous drug users, and homosexual or bisexual men are compared. RESULTS: TA-AIDS patients were older (mean, 46 years vs. < 40 for others, p < 0.05), more severely ill (59% had an alveolar-arterial oxygen gradient > 48.5 torr vs. 41% of others, p < 0.05), and less likely to have received PCP prophylaxis (16% of TA-AIDS patients versus 24–41% of others, p < 0.05). PCP care and outcomes also differed: TA-AIDS patients were less than half as likely to have early use of PCP medications (relative odds ratio = 0.45; 95% CI, 70% vs. > 80% for others, p < 0.05), more likely to be intubated (22% vs. 9–13% of others, p < 0.05), and more likely to die in-hospital (26% vs. 13- 22% of others, p < 0.05). After controlling for differences in severity of illness, insurance, age, and hospital characteristics, TA-AIDS patients were 45 percent as likely to have early PCP therapy (95% CI, 22%, 91%) as were persons in high-risk groups. CONCLUSION: For persons whose only risk factor was transfusion, recognition of the HIV infection and its complications appears to be problematic, which may help explain poorer outcomes in persons with HIV-related PCP.  相似文献   
997.
Introduction: Nerve regeneration across nerve constructs, such as acellular nerve allografts (ANAs), is inferior to nerve auto/isografts especially in the case of long defect lengths. Vascularization may contribute to poor regeneration. The time course of vascular perfusion within long grafts and constructs was tracked to determine vascularization. Methods: Male Lewis rat sciatic nerves were transected and repaired with 6 cm isografts or ANAs. At variable days following grafting, animals were perfused with Evans Blue albumin, and grafts were evaluated for vascular perfusion by a blinded observer. Results: Vascularization at mid‐graft was re‐established within 3–4 days in 6 cm isografts, while it was established after 10 days in 6 cm ANAs. Conclusions: Vascular perfusion is reestablished over a shorter time course in long isografts when compared with long ANAs. The differences in vascularization of long ANAs compared with auto/isografts suggest regenerative outcomes across ANAs could be affected by vascularization rates. Muscle Nerve 54 : 319–321, 2016  相似文献   
998.
Expression and release of CD27 in human B-cell malignancies   总被引:2,自引:2,他引:2  
CD27, a transmembrane disulfide-linked 55-kD homodimer, belongs to the nerve growth factor-receptor family, a group of homologous molecules involved in lymphocyte differentiation and selection. It is expressed on mature thymocytes, peripheral blood T cells, and a subpopulation of B cells. We investigated the expression of CD27 on malignant B cells representative for a broad range of stages in physiologic antigen- independent and -dependent B-cell development. In normal lymphoid tissue CD27+ B cells were only found in the peripheral blood (29.8% +/- 10.8%, n = 13) and in germinal centers. With the exception of pro-B and the majority of pre-pre-B acute lymphocytic leukemias and of myelomas, CD27 expression of variable intensity was detected on almost all immature and mature malignant B cells tested. Moreover, using a sandwich enzyme-linked immunosorbent assay we could show the presence of sometimes very high (up to 6,000 U/mL; normal values < 190 U/mL) amounts of the soluble 28- to 32-kD form of CD27 (sCD27) in the sera of patients with B-cell malignancies. The highest levels of sCD27 were observed in patients with chronic lymphocytic leukemia and low-grade non-Hodgkin's lymphomas. Most importantly, both in transversal and longitudinal studies, we found a strong correlation between sCD27 levels in the serum and tumor load, indicating that sCD27 can be used as a disease-marker in patients with acute and chronic B-cell malignancies.  相似文献   
999.
Thirty-eight children between the ages of 0.8 and 17 years with acute nonlymphoblastic leukemia in first remission induced by chemotherapy were given cyclophosphamide, total body irradiation, and bone marrow transplants from HLA-matched donors. Six patients died of pneumonia, one died of metabolic problems, and one died of chronic graft-v-host disease complications. Five patients relapsed between six months and 3.2 years after transplantation. Three of the five died of leukemia, one survives with leukemia three years after transplantation, and one survives in remission off treatment following chemotherapy for 22 months. Twenty-five survive in continuous remission from 1.7 to 8.4 years after transplantation, and the actuarial analysis shows a disease- free survival rate of 64%, with a plateau extending from 3.5 to 8.4 years. All lead normal lives.  相似文献   
1000.
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