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991.
Increasing numbers of elderly people are being treated in hospitals and are at particular risk of acquiring infections. The incidence, risk factors and types of hospital-acquired infection (HAI) in the elderly are reviewed. Special reference is made to urinary tract infections, respiratory tract infections, gastrointestinal infections including Clostridium difficile, bacteraemia, skin and soft tissue infections and infections with antibiotic-resistant organisms.  相似文献   
992.
A method for aligning cadaver knee specimens to a mechanical testing rig and determining local anatomical coordinate systems using landmarks identifiable on plane X-rays is introduced. Three sequential rotational alignments arc used to position the femur and tibia relative to the coordinate system of the testing mechanism. To validate this methodology five independent observers aligned the same knee specimen. The maximum error in the alignment orientations of the tibia and femur was 2.2 from the mean. These small misalignments produced variations of up to 4.7 in tibio-femoral rotations measured during knee flexion. Kinematic measurements of 15 specimens aligned using this procedure indicate that knee alignment is reproducible and physiologically relevant.  相似文献   
993.
OBJECTIVE: The number of geriatric patients seeking surgical treatment for cervical myelopathy is steadily increasing. Although anecdotal experiences have been good, insufficient data exists in the spine literature concerning this particular group. We decided to review our experience to determine efficacy of surgical management and examine our morbidity with this select group. METHODS: We undertook a retrospective review of all surgical procedures for nontraumatic cervical myelopathy performed at Mt Sinai Medical Center and Jackson Memorial Medical Center between January 1 1987 and June 1 1992, in patients older than 70 years of age (33 men and 18 women). RESULTS: A total of 53 cervical surgical procedures were performed in 51 patients (nine expansile laminoplasties, 20 anterior cervical diskectomies and fusion and 24 decompressive posterior laminectomies). The average hospital stay was 7.7 +/- 3.4 days. Twenty-one (41%) patients required inpatient rehabilitation; the remaining 30 patients received outpatient rehabilitative therapy. The major morbidity rate was 3.9%, and the minor morbidity rate was 5.8%. Perioperative medical complications included cardiac arrhythmias, hypertensive episodes, atelectasis, confusion, urinary dysfunction and hyponatremia. All of these complications resolved except in one patient. The perioperative mortality rate was 2%. Office follow-up was performed for a mean of 11.1 +/- 2.5 months postoperatively. Comparison of preoperative and postoperative functional status was performed using Nurick's criteria as described in the literature. At follow-up, 60.8% of the patients had improvement in their myelopathic symptoms, especially in regard to gait; 33.3% were stabilized and 5.9% had worsened neurological function. CONCLUSION: This study demonstrates that corrective surgical procedures for significant nontraumatic cervical myelopathy in the geriatric population may be performed safely, that is, with acceptable risk of morbidity and reasonable expectation for clinical improvement.  相似文献   
994.
STUDY OBJECTIVES: To determine whether British lung cancer (LC) trends are adequately explained by cigarette smoking trends, and whether modelling using aggregated smoking prevalence estimates can validly replace modelling using individual smoking histories. METHODS: Observed LC trends for 1955-1985 for both sexes and three age groups were compared with multistage model predictions using smoking history data from two surveys (HALS, AHIP). The modelling used the individual smoking data directly or aggregated prevalence estimates. It allowed for variation in age of starting and stopping smoking, amount smoked, tar levels, and environmental tobacco smoke (ETS) exposure. RESULTS: Observed male LC rates fell faster than predicted by a model (with the first and penultimate stages assumed affected by smoking) that allowed for variation in amount smoked and in tar level (with some provision for "compensation"), and was based on aggregated smoking data from HALS. The discrepancy equated to an annual change unexplained by smoking of -2.4%, -2.8%, and -1.9% for ages 35-44, 45-54, and 55-64. The annual unexplained changes were less in women, and reversed at age 55-64; -1.7%, -0.8%, and +0.8% for the three ages. They were similar using individual smoking histories (-2.6%, -1.8%, and -1.6%; women, -0.9%, -0.5%, and +0.2%). The discrepancies were unexplained by plausible alternative multistage parameters, full allowance for tar reduction, alternative estimates of amount smoked, or ETS. CONCLUSIONS: British LC trends cannot be fully explained by cigarette consumption trends, implying factors other than cigarette smoking contribute importantly to overall risk. Predictions using aggregated prevalence estimates provide useful information.  相似文献   
995.
Sixty-six human enterovirus serotypes have been described using antibody neutralization, with antigenic variants defined within several serotypes. Despite the availability of sequence data for numerous enteroviruses, the molecular basis of serotype is unknown. Previous studies by others have identified four major phylogenetic groups within the human enteroviruses, but there has been no complete database of homologous sequences for all human enterovirus serotypes. We have determined the homologous partial VP2 sequences for the 12 prototype strains for which VP2 sequence was unavailable and for eight well-characterized antigenic variants. Phylogenetic analysis of all prototype strains produced four major groups, consistent with published enterovirus phylogenies. Many antigenic variants, however, failed to cluster with their respective prototype strains, suggesting that this portion of VP2 may be inappropriate for consistent molecular inference of serotype and for detailed study of enterovirus evolution.  相似文献   
996.
AIM: Trial of the modified protocol BFM in the treatment of children with B-cell lymphomas. MATERIALS AND METHODS: 26 children with B-cell lymphoma were treated. Of them 2 children were treated according to the program for risk 2 group and 24 children were treated as risk 3 group. RESULTS: Complete remission was achieved in 23 patients. Two children were resistant. There were 2 cases of early recurrence, 1 case of early death, 1 case of death in remission. 20 patients are in complete remission. The 4-year survival is 78%. CONCLUSION: The modified protocol BFM proved to be highly effective against B-cell lymphoma in children. Its drawback is high toxicity.  相似文献   
997.
BACKGROUND: Platinum-based chemotherapy is the cornerstone of modern treatment for ovarian, testicular, and other cancers, but few investigations have quantified the late sequelae of such treatment. METHODS: We conducted a case-control study of secondary leukemia in a population-based cohort of 28,971 women in North America and Europe who had received a diagnosis of invasive ovarian cancer between 1980 and 1993. Leukemia developed after the administration of platinum-based therapy in 96 women. These women were matched to 272 control patients. The type, cumulative dose, and duration of chemotherapy and the dose of radiation delivered to active bone marrow were compared in the two groups. RESULTS: Among the women who received platinum-based combination chemotherapy for ovarian cancer, the relative risk of leukemia was 4.0 (95 percent confidence interval, 1.4 to 11.4). The relative risks for treatment with carboplatin and for treatment with cisplatin were 6.5 (95 percent confidence interval, 1.2 to 36.6) and 3.3 (95 percent confidence interval, 1.1 to 9.4), respectively. We found evidence of a dose-response relation, with relative risks reaching 7.6 at doses of 1000 mg or more of platinum (P for trend <0.001). Radiotherapy without chemotherapy (median dose, 18.4 Gy) did not increase the risk of leukemia. CONCLUSIONS: Platinum-based treatment of ovarian cancer increases the risk of secondary leukemia. Nevertheless, the substantial benefit that platinum-based treatment offers patients with advanced disease outweighs the relatively small excess risk of leukemia.  相似文献   
998.
In 1995, we mapped a gene for Lafora's progressive myoclonus epilepsy in chromosome 6q23-25. In 1997 and 1998, we reduced the size of the locus to 300 kb, and an international collaboration identified mutations in the protein tyrosine phosphatase gene. Here, we examine for heterogeneity through the admixture test in 22 families and estimate the proportion of linked families to be 75 to 85%. Extremely low posterior probabilities of linkage (Wi), exclusionary LOD scores, and haplotypes identify 4 families unlikely to be linked to chromosome 6q24.  相似文献   
999.
The bacterial capsule is an important virulence determinant in animal and plant disease. Bacterial capsule and slime can be inhibited by bismuth compounds, especially when complexed with lipophilic thiol chelators. Bismuth dimercaprol (BisBAL) at 1 ppm of Bi3+ repressed Klebsiella pneumoniae capsule expression in defined medium by nearly 90%, which exposed subsurface structures. The phagocytic index for BisBAL-treated bacteria increased from <10 to 360 bacteria per 100 neutrophils in the presence of complement and anticapsular or anti-O antigen antiserum. BisBAL treatment also enhanced the reactivity of monoclonal antibodies (MAbs) specific for the O1-antigen lipopolysaccharide (LPS) or the LPS core in a dose-dependent manner as indicated by the results of enzyme-linked immunosorbent assays. When anti-O1 MAb was used, the reactivity increased significantly for fully encapsulated O1:K1 or O1:K2 cells but not for O1:K- cells. Deposition of C3b also increased significantly for BisBAL-treated O1:K1 or O1:K2 cells but not for O1:K- cells. Survival of a serum-sensitive strain was <0.1% when nonimmune human serum absorbed with O1:K1 cells was used and 107% when BisBAL-treated cells were used for absorption. Outer membrane proteins were also more accessible on the surface of K. pneumoniae after BisBAL treatment. Thus, at subinhibitory levels, BisBAL inhibited capsule expression, which promoted phagocytosis, enhanced the reactivity of specific antibodies for LPS O antigen, LPS core epitopes, or outer-membrane proteins, and enhanced complement interaction with encapsulated K. pneumoniae. By unmasking bacterial surface structures and enhancing the immune system reactivity to bacteria, bismuth thiols may prove useful as adjuncts for vaccination.  相似文献   
1000.
1. Nursing home residents have the right to be involved in decision making relative to their care, which researchers have demonstrated has a positive effect on residents. 2. The authors designed a study to explore discrepancies between residents' perceptions of choice and the amount of choice preferred and their relationship to self-care abilities and functional abilities in nursing home residents. 3. The results indicate that residents desired more choice than they felt they were given, but that this difference was not related to their perceptions of their self-care abilities. As residents' functional abilities increased, actual choice as well as desired choice increased slightly. 4. Nurses should structure the nursing home's approach to residents so that choice is maximized within the constraints of the institution.  相似文献   
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