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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   
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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   
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Seid J  Asrat D 《Acta tropica》2005,95(2):143-148
Extended Spectrum beta-Lactamases (ESBLs) producer and multidrug resistant Klebsiella spp. are becoming a major nosocomial pathogen globally. There are no documented reports yet on the occurrence of ESBL enzymes in Klebsiella spp. species from Ethiopia. This study was undertaken to isolate and determine the occurrence of ESBLs and multi-drug resistant Klebsiella spp. in different clinical samples obtained from patients. A cross-sectional survey was conducted in four different hospitals of Harar region (Hiwot Fana, Misrak-Arbegnoch, Police and Army) from December 2003 to February 2004. Three hundred and eighty four clinical specimens (202 sputum, 164 urine and 18 pus) were collected from patients admitted in different wards. Antimicrobial susceptibilities were performed on 57 clinical isolates by standard disk diffusion procedures against eight antimicrobial agents. The ESBLs detection was made by using cefotaxime and ceftazidime alone and in combination with clavulanate. A total of 57 (15%) Klebsiella spp. were isolated from 384 patients. Of the 57 isolates, 33 (58%) were from sputum, 18 (31.5%) from urine and 6 (10.5%) from pus. Of the 57 Klebsiella spp., 54 (94.7%) were identified as K. pneumoniae and 3 (5.3%) as K. oxytoca. Resistance was found against cephalosporins [cefotaxime (39.0%), cefoxitin (39.0%), ceftazidime (40.0%), ceftriaxone (40.0%), cephalothin (42.0%)], chloramphenicol (70.0%), gentamicin (61.0%) and trimethoprim-sulphamethoxazole (65.0%). Analyzed Klebsiella isolates were characterized also by a high degree of multi-resistance (67.0%). In 19/57 (33.3%) of the Klebsiella isolates, ESBL production was detected. Rates of detection of ESBL producers were 42.1, 26.3, 26.3 and 5.3% in Hiwot-Fana, Misrak-Arbegnoch, Police and Army hospitals, respectively. Multi-drug resistant isolates were more prevalent among the ESBLs producers (95.0%) than non-producers (53.0%) (p=0.24). In conclusion, our results show that awareness of ESBL production by Klebsiella spp. is clinically important. In the absence of infection control measures, ESBL producing organisms readily pass horizontally from patient to patient. These strains also transiently colonize the hands of hospital staff members, thereby facilitating patient-to-patient transmission of the organism.  相似文献   
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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   
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