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Many studies have shown that health conditions experienced in childhood play an important role on an individual's adult mortality. Recent research suggests that past reductions in early life exposure to infectious diseases have been a major contributor to the historical decline in old-age mortality. Drawing on French-Canadian data from cohorts born in the 17th and 18th centuries, we test whether a progressive deterioration in early life conditions (as revealed by an increasing infant mortality rate) translates into a decrease in survival prospects in late life. We use traditional demographic measures such as the age-specific probability of death, and a series of proportional hazard models to control for familial and environmental conditions. Results point toward little evidence of any early life effects. The trend of increasing infant mortality does not correlate with a general increase of mortality in older ages within the same cohorts. Period changes affecting survival at older ages (war, epidemics) as well as demographic and biological characteristics shared within families have a much larger role in old-age mortality than early life characteristics shared within the same cohorts. 相似文献
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《Indian journal of medical microbiology》2014,32(3):310-314
This study was undertaken to evaluate the clinico-demographical profile of keratomycosis. (January 2004 to January 2012). The corneal scrapings were processed by direct microscopic methods and standard culture techniques. Of 209 cases of keratitis studied, culture yielded growth in 80 cases (38.3%). Out of these 80 cases of growth, fungi were isolated in 77.5% and bacteria in 22.5%. The spectrum of keratomycosis was Aspergillus flavus (22.5%), Fusarium solani (16.1%), A. fumigatus (11.3%), Candida albicans (6.4%), etc., Routine surveillance of fungal keratitis is necessary to know the existing and emerging pattern of pathogens and to prevent use of un-warranted anti-microbial therapy. 相似文献
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A robust estimate of the number and characteristics of persons released from prison in Australia
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Objective: To estimate the number and characteristics of adults released from prison in Australia. Method: We calculated ratios, stratified by age, sex and Indigenous status, by comparing the number of persons released from prison in New South Wales (NSW), with the number in NSW prisons on 30 June of the corresponding year. These stratified ratios were applied to Australia‐wide prison data to estimate the number and characteristics of persons released annually. Results: We estimated that in 2013, 38,576 persons were released from prison in Australia ? 25.3% more than the daily prison population. Young people, Indigenous people and women were over‐represented among those released. We estimated that 3.69 Indigenous women aged 18–24 were released annually for each equivalent person in prison; and 2.75 non‐Indigenous women aged 18–24 were released annually for each equivalent person in prison. Conclusions: The annual ‘flow’ through Australia's prisons is well in excess of the daily number, but information on those moving through prison systems is not yet publicly available. The characteristics of those released from prison differ meaningfully from those of people in prison. Routine, national reporting of prison separations is critical to informing upscaling and targeting of Throughcare services for this profoundly vulnerable population. 相似文献
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Abdullah Altunışık Serkan Gül Nurhayat Özdemir 《Anatomical record (Hoboken, N.J. : 2007)》2021,304(8):1745-1758
In this study, we used the skeletochronology method to estimate various growth parameters, such as age structure, minimum and maximum life span, age of sexual maturity, and the relationship between body size and weight of eight different populations of the variable toad, Bufotes viridis sitibundus, in Turkey. Further, we determined the relationship between these parameters and ecologic factors using the partial Mantel test. A significant difference was found among the populations with respect to age, body size, and body weight in both males and females. On average, the maximum life span was recorded as 10 years for males and 11 years for females. In the studied populations, the average age of sexual maturity ranged between 2 and 4 years for both sexes. Sexual dimorphism in terms of snout-vent length (SVL) was not observed between males and females in all the populations. Toads from the higher altitudes tended to be significantly larger, older, and heavier than those from lower altitudes. We concluded that altitude and temperature have an impact on the growth rate, body size, and body mass. 相似文献
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Finkelstein ME Doak DF George D Burnett J Brandt J Church M Grantham J Smith DR 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(28):11449-11454
Endangered species recovery programs seek to restore populations to self-sustaining levels. Nonetheless, many recovering species require continuing management to compensate for persistent threats in their environment. Judging true recovery in the face of this management is often difficult, impeding thorough analysis of the success of conservation programs. We illustrate these challenges with a multidisciplinary study of one of the world's rarest birds-the California condor (Gymnogyps californianus). California condors were brought to the brink of extinction, in part, because of lead poisoning, and lead poisoning remains a significant threat today. We evaluated individual lead-related health effects, the efficacy of current efforts to prevent lead-caused deaths, and the consequences of any reduction in currently intensive management actions. Our results show that condors in California remain chronically exposed to harmful levels of lead; 30% of the annual blood samples collected from condors indicate lead exposure (blood lead ≥ 200 ng/mL) that causes significant subclinical health effects, measured as >60% inhibition of the heme biosynthetic enzyme δ-aminolevulinic acid dehydratase. Furthermore, each year, ~20% of free-flying birds have blood lead levels (≥450 ng/mL) that indicate the need for clinical intervention to avert morbidity and mortality. Lead isotopic analysis shows that lead-based ammunition is the principle source of lead poisoning in condors. Finally, population models based on condor demographic data show that the condor's apparent recovery is solely because of intensive ongoing management, with the only hope of achieving true recovery dependent on the elimination or substantial reduction of lead poisoning rates. 相似文献
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Brenna M. Henn L. L. Cavalli-Sforza Marcus W. Feldman 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(44):17758-17764
Genetic and paleoanthropological evidence is in accord that today’s human population is the result of a great demic (demographic and geographic) expansion that began approximately 45,000 to 60,000 y ago in Africa and rapidly resulted in human occupation of almost all of the Earth’s habitable regions. Genomic data from contemporary humans suggest that this expansion was accompanied by a continuous loss of genetic diversity, a result of what is called the “serial founder effect.” In addition to genomic data, the serial founder effect model is now supported by the genetics of human parasites, morphology, and linguistics. This particular population history gave rise to the two defining features of genetic variation in humans: genomes from the substructured populations of Africa retain an exceptional number of unique variants, and there is a dramatic reduction in genetic diversity within populations living outside of Africa. These two patterns are relevant for medical genetic studies mapping genotypes to phenotypes and for inferring the power of natural selection in human history. It should be appreciated that the initial expansion and subsequent serial founder effect were determined by demographic and sociocultural factors associated with hunter-gatherer populations. How do we reconcile this major demic expansion with the population stability that followed for thousands years until the inventions of agriculture? We review advances in understanding the genetic diversity within Africa and the great human expansion out of Africa and offer hypotheses that can help to establish a more synthetic view of modern human evolution. 相似文献
9.
目的 了解上海市家庭医生签约现状,探讨社区就诊居民人口学特征与签约的关系.方法 采用自行编制的调查问卷,选取5个社区卫生服务中心拦截式调查社区就诊居民,共计调查1 021人,回收有效的959份,回收有效率为93.9%.结果 调查居民平均年龄(59.91±14.30)岁,其中50岁以上占81.2%,男性348人(36.3%),女性611人(63.7%),居民自报家庭医生签约率为30.2%,多因素非条件Logistic回归分析发现女性(OR=1.44,95%CI (1.04~2.00))、年龄大于70岁(OR=2.17,95%CI(1.13~4.14))以及长期服药(OR=2.66,95%CI(1.56~4.54))的人群更倾向于签约家庭医生.结论 病人自报家庭医生签约率尚低,在推广家庭医生签约制时,应在扩大宣传、完善基本配套政策措施上,重点从女性、70岁以上人群及长期服药人群入手,提高居民签约率,以带动其他居民. 相似文献
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K Nandar LW Ang J Tey L James KM Kyi Win CBE Chee OT Ng JL Cutter YT Wang 《HIV medicine》2018,19(1):59-64
Cross‐matching of records between Singapore's tuberculosis and HIV registries showed that 3.3% of individuals with tuberculosis (TB) were coinfected with HIV (2000?2014), the TB incidence among individuals with HIV infection was 1.65 per 100 person‐years, and 53% of coinfections were diagnosed within 1 month of each other. The findings supported joint prevention programmes for early diagnosis and treatment. 相似文献