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71.
The treatment of antibody-mediated spermagglutination by corticosteroidtherapy has a high incidence of side-effects and sperm washingis often followed by re-agglutination. The possibility of enzymaticdisagglutination was therefore investigated. In the first partof the study the effects of four proteases on sperm motility,vitality and longevity were evaluated. Subtilisin had prohibitivelydetrimental effects even at 10 U/ml. However, chymotrypsin (500U/ml), trypsin (500 U/ml) and papain (50 U/ml) had no adverseeffects. In the second series of experiments one or more ofthese latter three enzymes was found to disagglutinate spermatozoawhich had previously been incubated with sperm-agglutinatingantibody-positive sera in 87% of cases. Although further investigationis required, enzymatic disagglutination may be beneficial forthe treatment of immunologically mediated spermagglutination.  相似文献   
72.
Asthma is a very common chronic illness in Australia; however,unrecognized and undertreated asthma is responsible for muchpreventable morbidity in the community. In 1988, a coalitionof private and public sector agencies was formed to conducta national mass communications program aimed at increasing awarenessabout asthma. This pilot campaign comprised a mailout to allprimary care physicians and a mass media campaign, entitled"Could it be asthma?". The impact of this media-based strategywas assessed using population surveys of 1300 adults beforeand after the campaign. Following the campaign, recall of recentasthma media messages increased from 24 to 49% (P < 0.001)and the proportion who recognized possible asthma symptoms intheir household increased from 3.4 to 5.5% following the campaign.Of those with symptoms, twice as many reported that they visiteda doctor to have their symptoms assessed after the campaign.Knowledge of asthma symptoms was significantly higher followingthe campaign (P < 0.001), after adjustment for age, sex andthe presence of asthma in the respondents family. The campaignappeared to have some success in raising awareness about asthma,and has been followed by the development of a National AsthmaCampaign in Australia focusing on reducing asthma morbidityand improving its management.  相似文献   
73.
The article describes the computerized system developed and used at the Ohio State University Medical Center in Columbus, Ohio to affix a physician's signature electronically. The system electronically sends dictated reports (e.g., discharge summaries, history and physical examinations, and operative reports) and attestation statements to the physician for review. The physician selects the report individually and may approve or enter comments. Comments are forwarded electronically to medical information management. The article describes the fiscal intermediary's requirements and approval process and the impact on delinquent records and accounts awaiting attestation signature before billing.  相似文献   
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Summary PD153035 is a potent (Ki=6 pm) and specific inhibitor of the epidermal growth factor (EOF) receptor tyrosine kinase that suppresses tyrosine phosphorylation of the EGF receptor in A431 cells at nanomolar concentrations in cell culture. We have examined the pharmacokinetics of this compound and its ability to rapidly suppress phosphorylation of the EGF receptor in A431 human epidermoid tumors grown as xenografts in immunodeficient nude mice. Following a single i.p. dose of 80 mg/kg, the drug levels in the plasma and tumor rose to 50 and 22 M within 15 minutes. While the plasma levels of PD153035 fell below 1 M by 3 hours, in the tumors it remained at micromolar concentrations for at least 12 hours. The tyrosine phosphorylation of the EGF receptor was rapidly suppressed by 80–90% in the tumors. However receptor phosphorylation returned to control levels after 3 hours despite the continued presence of the drug at concentrations which, based on previousin vitro results, were predicted to maintain inhibition. EGF-stimulated tyrosine kinase activity in tumor extracts was decreased and recovered in parallel with the effects of PD153035 on receptor phosphorylation though the activity had reached only about half of the control activity after three hours. These results demonstrate the potential for using small molecule inhibitors to inhibit the EGF receptor tyrosine kinasein vivo, though a fair evaluation of their potential anti-cancer activity will have to wait for solutions to problems with sustained delivery which may allow us to maintain suppression of EGF receptor phosphorylation.  相似文献   
76.
The effect of pesticide exposure on time to pregnancy   总被引:10,自引:0,他引:10  
The Ontario Farm Family Health Study provided data for examination of the effects of pesticide exposure on time to pregnancy. In this retrospective cohort study of farm couples in Ontario, Canada, the farm operator, husband, and wife completed questionnaires during 1991-1992. We asked about pesticides used on the farm and pesticide activities of the husband and wife for each month of trying to conceive. After exclusions, 2,012 planned pregnancies remained for analysis. We used an analog of the Cox proportional hazards model to calculate conditional fecundability ratios (conditional on pregnancy). There was no strong or consistent pattern of associations of pesticide exposure with time to pregnancy. During exposure intervals in which women participated in pesticide activities (during most of which the men also participated), however, 6 of 13 pesticide exposure categories were associated with a decrease in fecundability (conditional fecundability ratio range = 0.51-0.80). For exposure intervals in which only the men participated in pesticide activities or in which neither men nor women participated in pesticide activities but pesticides had been used on the farm, conditional fecundability ratios ranged from 0.75 to 1.50, with no apparent consistency among pesticide classes, chemical families, or active ingredients.  相似文献   
77.
The United States Military deploys its forces with minimal lead time. These forces must be medically qualified and physically fit for any locale and mission scenario. Historically, up to half of the force identified for deployment at any given time were not medically qualified. Matching individuals to specific occupations using validated medical and physical performance standards is an occupational medicine tenet that increases the effectiveness and efficiency of the workforce. To establish a cost-effective, valid medical program ensuring a fit and ready force, the military must: (1) develop validated physical fitness/occupational standards; (2) consolidate one fitness standard for males/females on the basis of workload requirements; (3) eliminate differing age standards; (4) provide statistically relevant medical screening, testing for health maintenance, and fitness for duty; and (5) mandate one joint medical standard for all military services.  相似文献   
78.
The design and coordination of antirabies measures (e.g., oral vaccine and disease awareness campaigns) often depend on surveillance data. In Kentucky, health officials are concerned that the raccoon rabies epizootic that has spread throughout the east coast since the late 1970s could enter the state. The quality of surveillance data from Kentucky's 120 counties, however, may not be consistent. This article presents a geographic model that can be used with a geographic information system (GIS) to assess whether a county has a lower number of animals submitted for rabies testing than surrounding counties. This technique can be used as a first step in identifying areas needing improvement in their surveillance scheme. This model is a variant of a spatial filter that uses points within an area of analysis (usually a circle) to estimate the value of a central point. The spatial filter is an easy-to-use method of identifying point patterns, such as clusters or holes, at various geographic scales (county, intraurban), by using the traditional circle as an area of analysis or a GIS to incorporate a political shape (county boundary).  相似文献   
79.
80.
This article uses linked data from the 1995 Morocco DHS calendar and the 1992 Morocco DHS service-availability module to study the effect of service environment on contraceptive discontinuation, switching, and adoption of a modern method following a birth. The 1995 Morocco DHS also collected information on the source of supply for each episode of use of a modern method recorded in the calendar, allowing study of the association between the source of supply and discontinuation and switching rates. Multilevel event-history models are used to evaluate the impact of individual-level sociodemographic characteristics and community-level indicators of family planning service provision. The findings show that the presence of a nearby public health center is associated with higher modern-method adoption after a birth and lower method-failure rates; the presence of a pharmacy is associated with lower discontinuation due to side effects or health concerns. The degree of method-choice potential has a positive impact on both the rate of switching from the pill to another modern method and on modern-method adoption after a birth.  相似文献   
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