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1.
This paper addresses an evaluation of an administrative decision to change the manner in which services were paid for at a Student Health Center (SHC). The impact of the change in payment was observed through monitoring the number of scheduled appointments at the SHC which the patient failed to attend, reschedule, or cancel. The impact was assessed through a comparison of the weekly no-show rates from the year prior to the change in payment practices through the year following the change. A time-series statistical package was used to analyze the no-show data. Collateral measures on the number of students attending the university, staff opinions, and usage of the SHC by different student groups were collected. Evaluations of the impact of administrative decisions on health-related behavior were discussed, in addition to a discussion of the usefulness of time-series models for this type of evaluation.  相似文献   
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目的探讨石家庄市大气气态污染物SO2、NO2、O3-8 h和CO浓度与居民每日死亡人数之间的关系。方法收集石家庄市2013—2016年每日死亡人数、大气污染物浓度、气象资料,采用广义相加时间序列模型,分析气态污染物浓度对死亡的影响,并按照性别、年龄进行分层分析。结果大气SO2浓度每增加10μg/m3,人群非意外总死亡和因循环系统疾病死亡的风险分别增加0.46%(0.02%,0.90%)和0.75%(0.07%,1.42%);NO2浓度每增加10μg/m3,人群非意外总死亡和因循环系统疾病死亡的风险分别增加1.00%(0.26%,1.74%)和1.30%(0.16%,2.44%);O3-8 h和CO对死亡风险存在正向影响,但无统计学意义。分层分析表明,SO2对女性健康的影响要高于男性,且差异具有统计学意义;NO2对女性健康的影响要高于男性,对65岁及以上人群的影响明显高于(0~64)岁人群,但两者的差异均不具有统计学意义。结论石家庄市大气气态污染物中SO2和NO2污染较为严重,其浓度的升高会增加居民非意外死亡和循环系统疾病死亡的风险。建议政府和民众在防护颗粒物污染的同时,也要关注气态污染物对人群健康的影响,并加强对女性的防护。  相似文献   
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《Vaccine》2022,40(41):5950-5958
BackgroundLimited data are available on long-term indirect effects of ten-valent pneumococcal conjugate vaccine (PCV10) programmes. We evaluated changes in invasive pneumococcal disease (IPD) incidence, mortality, and serotype distribution in adults up to 9 years after infant PCV10 introduction.MethodsCulture-confirmed IPD cases ≥18 years (n = 5610; 85% were pneumonia) were identified through national, population-based laboratory surveillance; data were linked with population registry to conduct nationwide follow-up study. In a time-series model, we compared serotype-specific IPD incidence and associated 30-day mortality rates before and after PCV10 by using negative binomial regression models.ResultsDuring pre-PCV10 period (7/2004–6/2010), overall IPD incidence in adults ≥18 years increased yearly by 4.8%. After adjusting for trend and seasonality, the observed PCV10 serotype IPD incidence in 7/2018–6/2019 was 90% (12/100,000 person-years) lower than the expected rate without PCV10 program. Non-PCV10 serotype incidence was 40% (4.4/100,000 person-years) higher than expected; serotypes 3, 19A, 22F, and 6C accounted for most of the rate increase. However, incidence of non-PCV10 IPD levelled off by end of follow-up. The observed-expected incidence rate-ratio (IRR) was 0·7 (95 %CI 0·5–0.8) for all IPD and 0·7 (95 %CI 0·3–1·3) for IPD-associated 30-day mortality. Case-fatality proportion decreased from 11·9% to 10.0% (p < 0.01). In persons ≥65 years, the IRR was 0·7 (95 %CI 0·5–0.95).ConclusionsSignificant indirect effects were seen for vaccine-serotype IPD and for overall IPD in all adult age groups. For non-vaccine IPD, the incidence stabilized 5 years after infant PVC10 program introduction, resulting in a steady state in which non-vaccine IPD accounted for nearly 90% of overall IPD. Substantial pneumococcal disease burden remains in older adults.  相似文献   
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目的 分析大气污染急性暴露对居民每日脑卒中死亡的影响。方法 采用时间序列的半参数广义相加模型 ,在控制死亡的长期趋势、气象因素、“星期几效应”等混杂因素的基础上 ,分析了上海市某区 2 0 0 1年 1月 1日~ 12月 31日大气污染与居民每日脑卒中死亡的关系。结果 大气PM10 ,SO2 和NO2 4 8h平均浓度每增加 10 μg m3 ,居民因脑卒中而死亡的相对危险度分别为 1 0 0 8(95 %CI 1 0 0 0~ 1 0 16 ) ,1 0 17(95 %CI 0 998~ 1 0 36 )和 1 0 2 9(95 %CI1 0 0 1~ 1 0 5 7)。结论 上海市某区目前的PM10 和NO2 水平对居民脑卒中死亡有影响。  相似文献   
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Meta-analysis is applied to aggregate-level studies that model the demand for cigarettes using static, myopic, or rational addiction frameworks in an attempt to synthesize key findings in the literature and to identify determinants of the variation in reported price elasticity estimates across studies. The results suggest that the rational addiction framework produces statistically similar estimates to the static framework but that studies that use the myopic framework tend to report more elastic price effects. Studies that applied panel data techniques or controlled for cross-border smuggling reported more elastic price elasticity estimates, whereas the use of instrumental variable techniques and time trends or time dummy variables produced less elastic estimates. The finding that myopic models produce different estimates than either of the other two model frameworks underscores that careful attention must be given to time series properties of the data.  相似文献   
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The effectiveness of the utensil swab test as part of the periodic inspection of food establishments was studied both as an indicator of cleanliness during the period between inspections and as an educational tool.

Two to seven samplings were taken at intervals of two to three months at 95 food establishments in rural areas in the northern part of Israel. A statistical analysis showed a high variation and almost no correlation between repeated samplings of the same establishment. Also, no trend to suggest an educational effect was found. We concluded that, though the swab test had proved to be useful in special projects, it had no value as part of the periodic sanitary inspections.  相似文献   
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The patterns of variations in fisheries time series are known to result from a complex combination of species and fisheries dynamics all coupled with environmental forcing (including climate, trophic interactions, etc.). Disentangling the relative effects of these factors has been a major goal of fisheries science for both conceptual and management reasons. By examining the variability of 169 tuna and billfish time series of catch and catch per unit effort (CPUE) throughout the Atlantic as well as their linkage to the North Atlantic Oscillation (NAO), we find that the importance of these factors differed according to the spatial scale. At the scale of the entire Atlantic the patterns of variations are primarily spatially structured, whereas at a more regional scale the patterns of variations were primarily related to the fishing gear. Furthermore, the NAO appeared to also structure the patterns of variations of tuna time series, especially over the North Atlantic. We conclude that the patterns of variations in fisheries time series of tuna and billfish only poorly reflect the underlying dynamics of these fish populations; they appear to be shaped by several successive embedded processes, each interacting with each other. Our results emphasize the necessity for scientific data when investigating the population dynamics of large pelagic fishes, because CPUE fluctuations are not directly attributable to change in species' abundance.  相似文献   
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目的探索大气二氧化氮(NO_2)对苏州市居民肺癌发病、死亡影响的程度和特点,确定滞后时间,评估健康效应。方法收集2006—2014年苏州市居民肺癌发病、死亡资料,大气污染物和气象数据,采用时间序列的广义相加模型,在控制长期趋势、星期几效应和气象因素的影响后,定量分析单污染物模型和双污染物模型中,大气NO_2对肺癌发病死亡人数的影响。结果单污染物模型中,滞后3天的NO_2(lag3)对肺癌日发病数的效应有统计学意义(P=0.03)。随着NO_2浓度每升高10μg/m~3,肺癌全人群和女性人群日发病数分别增加1.001%(95%CI:0.075,1.926)和2.541%(95%CI:0.744,4.338)。双污染物模型结果显示,NO_2对肺癌发病影响需要和PM2.5相互作用才发挥效应,不受SO_2和PM10的影响。结论苏州市肺癌,特别是女性肺癌发病人数随着大气NO_2浓度的增加而呈上升趋势;其影响存在滞后性,需要PM2.5的联合作用才能发挥效应。  相似文献   
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Hepatitis A incidence has been decreasing in Brazil since child vaccination was implemented in 2014. This trend was interrupted by an outbreak among adult male in São Paulo in 2017. This study was outlined to estimate whether the increase of hepatitis A cases among adult men in Brazil was restricted to São Paulo. Cases reported to the national surveillance system from 14 large cities of all Brazilian regions were analyzed. Trends in time series from 2012 to 2018 were estimated by Prais-Winsten regression. The outbreak in São Paulo extended to 2018. In Rio de Janeiro, the number of cases rose again, achieving the same levels reported before the vaccination era. Three of six cities from South and Southeast regions showed an upward trend in the number of cases among adult men (P < .005). The large cities in the other three Brazilian macroregions showed a decrease or stabilization of cases without an increase among male adults. The increase of hepatitis A virus (HAV) cases in Brazil has happened not only in São Paulo, but also in other cities of South and Southeast regions. The northernmost cities were not affected. A change in the epidemiological pattern of HAV infection is emerging in Southern Brazil.  相似文献   
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