全文获取类型
收费全文 | 263篇 |
免费 | 45篇 |
专业分类
耳鼻咽喉 | 2篇 |
基础医学 | 13篇 |
临床医学 | 5篇 |
内科学 | 14篇 |
皮肤病学 | 1篇 |
神经病学 | 1篇 |
外科学 | 13篇 |
综合类 | 3篇 |
预防医学 | 31篇 |
药学 | 32篇 |
中国医学 | 3篇 |
肿瘤学 | 190篇 |
出版年
2024年 | 5篇 |
2023年 | 4篇 |
2022年 | 8篇 |
2021年 | 16篇 |
2020年 | 17篇 |
2019年 | 18篇 |
2018年 | 13篇 |
2017年 | 10篇 |
2016年 | 19篇 |
2015年 | 14篇 |
2014年 | 19篇 |
2013年 | 12篇 |
2012年 | 27篇 |
2011年 | 12篇 |
2010年 | 7篇 |
2009年 | 11篇 |
2008年 | 8篇 |
2007年 | 12篇 |
2006年 | 13篇 |
2005年 | 12篇 |
2004年 | 8篇 |
2003年 | 10篇 |
2002年 | 8篇 |
2001年 | 4篇 |
2000年 | 10篇 |
1999年 | 3篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1982年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有308条查询结果,搜索用时 15 毫秒
1.
H. H. Schubiner W. D. LeBar S. Joseph C. Taylor C. Jemal 《European journal of clinical microbiology & infectious diseases》1992,11(6):553-556
The performance of two new enzyme immunoassays (EIA) for the detection ofChlamydia trachomatis in a practice setting was compared. A consecutive series of 207 female patients seen at an inner-city sexually transmitted disease clinic were tested by cell culture, the Kodak SureCell (SC) and Abbott TestPack Chlamydia (TP) EIAs. In addition 210 male patients, selected by physicians on the basis of the fact that multiple urethral samples could be obtained, were tested by cell culture and SC. The prevalence of infection was 19 % in the females and 12.5 % in males. The sensitivity, specificity, positive predictive value and negative predictive value for the SC and TP were 88 %, 95 %, 81 %, 97 % and 59 %, 99 %, 95 %, 91 %, respectively, in the female population. The sensitivity of the SC was significantly greater than that of the TP (p 0.002). The performance values of the SC in men (in the same order) were 64 %, 96 %, 71 % and 95 %, respectively. The SC in male patients and the TP in female patients had low sensitivity. The sensitivity of the SC in female patients was significantly higher than that of the TP. However, the SC yielded more false positive results. To determine the utility of these tests in a practice setting further studies are required. 相似文献
2.
Jemal Abawajy Andrei Kelarev Morshed Chowdhury Andrew Stranieri Herbert F. Jelinek 《Computers in biology and medicine》2013
Cardiovascular autonomic neuropathy (CAN) is a serious and well known complication of diabetes. Previous articles circumvented the problem of missing values in CAN data by deleting all records and fields with missing values and applying classifiers trained on different sets of features that were complete. Most of them also added alternative features to compensate for the deleted ones. Here we introduce and investigate a new method for classifying CAN data with missing values. In contrast to all previous papers, our new method does not delete attributes with missing values, does not use classifiers, and does not add features. Instead it is based on regression and meta-regression combined with the Ewing formula for identifying the classes of CAN. This is the first article using the Ewing formula and regression to classify CAN. We carried out extensive experiments to determine the best combination of regression and meta-regression techniques for classifying CAN data with missing values. The best outcomes have been obtained by the additive regression meta-learner based on M5Rules and combined with the Ewing formula. It has achieved the best accuracy of 99.78% for two classes of CAN, and 98.98% for three classes of CAN. These outcomes are substantially better than previous results obtained in the literature by deleting all missing attributes and applying traditional classifiers to different sets of features without regression. Another advantage of our method is that it does not require practitioners to perform more tests collecting additional alternative features. 相似文献
3.
4.
Saurabh Chavan Freddie Bray Joannie Lortet-Tieulent Michael Goodman Ahmedin Jemal 《European urology》2014
Context
Previous studies have reported substantial worldwide regional variations in bladder cancer (BCa) incidence and mortality.Objective
To describe contemporary international variations in BCa incidence and mortality rates and trends using the most recent data from the International Agency for Research on Cancer (IARC).Evidence acquisition
Estimated 2008 BCa incidence and mortality rates for each country by sex were obtained from GLOBOCAN. Recent trends in incidence for 43 countries and in mortality for 64 countries were assessed by join-point model using data from the IARC's Cancer Incidence in Five Continents and from the World Health Organisation's mortality database, respectively.Evidence synthesis
The highest incidence rates for both men and women are found in Europe, the United States, and Egypt, and the lowest rates are found in sub-Saharan Africa, Asia, and South America. Mortality rates are highest in parts of Europe and northern Africa and lowest in Asia, Central America, and middle Africa. Incidence rates among men decreased in 11 of 43 countries (46 registries) (North America, western and northern Europe), remained stable in 20, and increased in 12 countries (southern, central, and eastern Europe). Among women, incidence rates decreased in 10 countries, stabilised in 22 countries, and increased in 12 countries. Mortality rates among men decreased in 32 of 65 countries (throughout all world regions except Central and South America), stabilised in 30 countries, and increased in 3 (Romania, Slovenia, and Cuba). Among women, mortality rates decreased in 24 countries, remained stable in 36 countries, and increased in 5 countries (central and eastern Europe).Conclusions
Incidence and mortality rates in general decreased in most Western countries but increased in some eastern European and developing countries. These patterns in part may reflect differences in the stage and extent of the tobacco epidemic, changes in coding practices, prevalence of schistosomiasis (Africa), and occupational exposure. 相似文献5.
A cross-sectional study was carried out from November 2010 through April 2011 to determine the prevalence, risk factors, number, size, and fertility of hydatid cysts in infected organs and assess the economic losses due to condemnation of organs in sheep and goats slaughtered in different restaurants in Jimma Town. For this purpose, a total of 804 small ruminants (502 sheep and 302 goats) slaughtered in Jimma Town were examined for presence of hydatid cysts. Hydatid cysts were detected in 149 (29.5 %) sheep and 75 (24.8 %) goats examined. Results of the study showed that statistically significant variation was never observed in the prevalence of hydatid cysts between sheep and goat hosts. In the study, 162 (25.8 %) males and 62 (35.5 %) females were found to harbor hydatid cysts in one or more of their organs. Significantly higher prevalence in females than males was recorded. An overall prevalence of 26.3 % in young and 29.4 % in adult sheep and goats of hydatid cysts was recorded. Our study showed that the liver was the most commonly infected organs of sheep and goats with the prevalence of 50.7 % followed by the lungs (37.5 %) whereas the rest 11.3 % was mixed infection. In sheep, out of the total 508 cysts collected, 38.6 % small, 45.5 % medium, and 21.3 % large were recorded. Similarly, for goats, the corresponding values of 33.8, 43.5, and 22.4 % were detected, respectively. In this study, a total of 168 from sheep and 135 cysts from goats collected from different infected organs were subjected to fertility and viability studies. Results of the study revealed that out of the total 95 (56.5 %) of the fertile cysts in sheep, 81 (85.3 %) were viable; however, the rest 14 (14.7 %) were nonviable. In goats, out of the total 59 (43.7 %) of the fertile cysts, 44 (74.6 %) were viable; however, the rest 15 (25.4 %) were nonviable. Significantly higher numbers of fertile cysts were recorded in the livers than in the lungs in both sheep and goats hosts. The total annual economic loss incurred due to cystic echinococcosis in sheep and goats slaughtered in restaurants in Jimma Town was estimated to be 149,312.8 USD (249,324 ETB). In view of the findings of the current study, there is a need and recommendation for proper disposal of offal, reduction of backyard slaughtering, and control of stray dogs to prevent the economic losses and public health hazard associated with the cystic echinococcosis. The findings of the current study imply that cystic echinococcosis is highly prevalent and incurs huge financial losses through condemnation of infected internal organs in sheep and goats slaughtered in Jimma. Further epidemiological studies on the comparative importance of intermediate host species, definitive hosts, genotype of strains from different host species, and zoonotic and economic significance of cystic echinococcosis are urgently needed in different parts of Ethiopia. 相似文献
6.
7.
8.
9.
10.
Miranda M. Fidler-Benaoudia Lindsey A. Torre Freddie Bray Jacques Ferlay Ahmedin Jemal 《International journal of cancer. Journal international du cancer》2020,147(3):811-819
Previous studies have reported converging lung cancer rates between sexes. We examine lung cancer incidence rates in young women vs. young men in 40 countries across five continents. Lung and bronchial cancer cases by 5-year age group (ages 30–64) and 5-year calendar period (1993–2012) were extracted from Cancer Incidence in Five Continents. Female-to-male incidence rate ratios (IRRs) and 95% confidence intervals (95%CIs) were calculated by age group and birth cohort. Among men, age-specific lung cancer incidence rates generally decreased in all countries, while in women the rates varied across countries with the trends in most countries stable or declining, albeit at a slower pace compared to those in men. As a result, the female-to-male IRRs increased among recent birth cohorts, with IRRs significantly greater than unity in Canada, Denmark, Germany, New Zealand, the Netherlands and the United States. For example, the IRRs in ages 45–49 year in the Netherlands increased from 0.7 (95% CI: 0.6–0.8) to 1.5 (95% CI: 1.4–1.7) in those born circa 1948 and 1963, respectively. Similar patterns, though nonsignificant, were found in 23 additional countries. These crossovers were largely driven by increasing adenocarcinoma incidence rates in women. For those countries with historical smoking data, smoking prevalence in women approached, but rarely exceeded, those of men. In conclusion, the emerging higher lung cancer incidence rates in young women compared to young men is widespread and not fully explained by sex differences in smoking patterns. Future studies are needed to identify reasons for the elevated incidence of lung cancer among young women. 相似文献