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排序方式: 共有1191条查询结果,搜索用时 15 毫秒
41.
42.
An assessment of polymorphonuclear leukocyte rigidity in HIV-infected individuals after immune recovery 总被引:1,自引:0,他引:1
Goldenberg DT Holland GN Cumberland WG Fisher TC Folz IC Wang RC Terry BG Moe AA Kramer F Lim JI Rao NA Meiselman HJ 《Investigative ophthalmology & visual science》2002,43(6):1857-1861
PURPOSE: To determine whether polymorphonuclear leukocytes (PMNs) remain rigid after immune reconstitution in human immunodeficiency virus (HIV)-infected individuals with a history of severe immunosuppression. METHODS: PMN rigidity was measured in vitro in three groups: (1) HIV-infected individuals with a history of CD4+ T-lymphocyte counts of less than 50/microL, but with current counts of more than 200/microL attributable to potent antiretroviral therapy (group 1); (2) HIV-infected individuals whose CD4+ T-lymphocyte counts had always been more than 200/microL (group 2); and (3) HIV-negative control subjects. Rigidity was determined with a cell transit analyzer (containing a micropore filter with 30 identical, 8-microm diameter pores), representing a simple in vitro model of a capillary bed. A longer PMN pore transit time reflects increased PMN rigidity. RESULTS: PMN transit time (median) in group 1 (n = 11) was 3.34 ms, in group 2 (n = 9) was 3.19 ms, and in control subjects (n = 15) was 2.66 ms. PMN rigidity was significantly greater in groups 1 (P = 0.014) and 2 (P = 0.046) than in control subjects (Wilcoxon rank-sum test). A significant difference was not identified between groups 1 and 2 (P = 0.518). CONCLUSIONS: The increased PMN rigidity known to occur in severely immunosuppressed HIV-infected individuals persists after immune reconstitution. Furthermore, PMN rigidity is increased in those HIV-infected individuals who do not have a history of severe immunosuppression. Because PMN rigidity can alter microvascular blood flow, HIV-infected individuals may remain at risk for retinal vascular damage in the era of potent antiretroviral therapy. 相似文献
43.
Giancola PR Helton EL Osborne AB Terry MK Fuss AM Westerfield JA 《Journal of studies on alcohol》2002,63(1):64-73
OBJECTIVE: The purpose of this study was to investigate the manner in which acute alcohol consumption and provocation affect aggressive behavior in men and women. METHOD: Subjects were 102 (56 men) healthy social drinkers between 21 and 35 years of age. Aggression was measured using a modified version of the Taylor Aggression Paradigm, in which electric shocks are received from and administered to a fictitious opponent during a competitive task. RESULTS: Provocation was a stronger elicitor of aggression than either gender or alcohol. Under low provocation, men were more aggressive than were women. Under high provocation, men and women were equally aggressive, except in the case of extreme aggression, in which men again exhibited higher levels than did women. Alcohol increased aggression for men but not for women. CONCLUSIONS: These results are important because there now appears to be some convergence among studies indicating that, whereas provocation and alcohol are effective in lifting inhibitions against the expression of aggression for men, only provocation seems to be an effective aggression-elicitor for women. 相似文献
44.
This review paper discusses potential relationships between Cholesterol levels, the therapeutic use of Statins and the risk of Alzheimer s Disease. Comparisons have also been made between the Western populations and Oriental populations. Epidemiological studies have shown that statins, which reduce the levels of plasma cholesterol by inhibiting the enzyme 3 hydroxy-3methylglutaryl-coenzyme A (HMGCoA) reductase, reduce the risk of Alzheimer s disease by up to 70%. Further research is required to determine whether cholesterol levels have a direct, causative, or indirect relationship with Alzheimer disease. Also, it is not clear why some statins reduce the prevalence of AD and others do not. Statins may have an affect on other AD risk factors, or act by mechanisms which are independent of their effects on cholesterol levels? 相似文献
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Terry DA McGuire MK McLaren E Fulton R Swift EJ 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》2003,15(5):284-296
Several classes of tooth-colored materials are available for restoring carious and noncarious cervical lesions. Included are the composite resins, which can be bonded into the cervical area to provide predictable form, function, and esthetics. Part I of this two-part report reviewed the etiology of noncarious cervical lesions and provided a series of clinical case reports showing the importance of the periodontal aspect of lesion management. In part II we present information about adhesive preparation design and esthetic restoration of the noncarious cervical lesion.
CLINICAL SIGNIFICANCE
When used with proper attention to preparation design and restoration placement and finishing, resin composites can be used to successfully restore form, function, and esthetics to defective cervical areas of teeth. 相似文献
CLINICAL SIGNIFICANCE
When used with proper attention to preparation design and restoration placement and finishing, resin composites can be used to successfully restore form, function, and esthetics to defective cervical areas of teeth. 相似文献
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The omega-3 fatty acids, especially long-chain eicosapentaenoic acid (20:5n-3) and docosahexaenoic (22:6n-3) contained in "fatty" fish, have consistently been shown to retard the growth of breast cancer in vitro and in animal experiments. In contrast, studies of the association between fish consumption and breast cancer risk in human populations have not consistently shown inverse associations. However, previous studies have not considered the specific types of fish consumed. Using data from a large, nationwide case-control study conducted in Sweden, we examined the association between consumption of fatty and lean fish and breast cancer risk. Odds ratios (OR) and 95% confidence intervals were computed from unconditional logistic regression models. High consumption of fish was weakly associated with reduced breast cancer risk, and the association was not statistically significant. With multivariate adjustment, the OR for women with the highest consumption (> or =3.5 servings/wk) compared with women with the lowest (virtually none) was 0.88 (95% confidence interval = 0.60-1.29, P for trend = 0.15). When type of fish was examined separately, the association was similar for fatty and lean fish. 相似文献
50.
Dietary calcium and vitamin D intake and risk of colorectal cancer: a prospective cohort study in women 总被引:5,自引:0,他引:5
Although laboratory data and a few adenoma prevention trials suggest that calcium supplementation may reduce the risk of colorectal neoplasia, the results of observational studies of calcium intake and colorectal cancer risk are contradictory. However, few studies have examined the association among women or effects in specific colon subsites. Women with colorectal cancer diagnosed through 31 December 2000 were identified by linkage to regional cancer registries. During an average 11.3 yr of follow-up of 61,463 women, we observed 572 incident cases of colorectal cancer. Using data obtained from a 67-item food frequency questionnaire and Cox proportional hazards models to estimate rate ratios and 95% confidence intervals, we found an inverse association between dietary calcium intake and colorectal cancer risk. Women with the highest calcium intake (median 914 mg/day) had a reduced risk of colorectal cancer (rate ratio = 0.72, 95% confidence interval = 0.056-0.93, P for trend = 0.02) compared with women with the lowest intake (median 486 mg/day). Furthermore, our results suggest that the inverse association may be strongest in relation to distal cancers and among older women. The association with dairy products was less clear, suggesting that calcium intake per se is more important than specific calcium sources. Vitamin D intake was not clearly associated with risk. In sum, our data suggest that high calcium intake may lower colorectal cancer risk. 相似文献