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91.
目的:探讨在缺氧性损害下肼屈嗪对视网膜色素上皮(ARPE-19)细胞的抗氧化效果以及活性氧(ROS)在此效果中的作用。方法:用人视网膜色素上皮细胞研究肼屈嗪对氧化应激的作用,包括特丁基氢过氧化物(t-BHP)、过氧化氢(H2O2)、叠氮化钠(NaN3),以及缺氧引起的细胞坏死。用MTT检验测试细胞活性。结果:用ROS诱导的氧化应激治疗ARPE-19细胞,肼屈嗪在抵抗t-BHP、H2O2、缺氧引起的细胞坏死中表现出浓度依赖性,但对NaN3不具有浓度依赖性。这一作用中不涉及到一氧化氮(NO)。结论:肼屈嗪在ARPE-19细胞中表现出抗氧化应激诱导的破坏,这一作用可能是因为对ROS的净化剂作用。所以肼屈嗪可能用于治疗老年黄斑变性。 相似文献
92.
Plasmid DNA encoding herpes simplex virus type-1 glycoprotein D (gD-1) was complexed with asialoorosomucoid conjugated to poly-L-lysine. Following its intravenous injection into BALB/c mice, this complex was targeted to the liver. Liver cells expressing gD-1 were detected immunohistochemically through day 6 post-immunization, while gD-1 DNA was detectable through 14 days post-immunization. Decline of gD-1 expression and detectable gD-1 DNA in the liver correlated with influx of T cells, predominantly CD4(+). The ASOR-poly-L-lysine DNA carrier system promotes hepatic expression of gD-1 and may be useful in vaccination against herpes simplex virus type-1. 相似文献
93.
94.
Long-term arsenic exposure and incidence of non-insulin-dependent diabetes mellitus: a cohort study in arseniasis-hyperendemic villages in Taiwan 总被引:11,自引:0,他引:11
Tseng CH Tai TY Chong CK Tseng CP Lai MS Lin BJ Chiou HY Hsueh YM Hsu KH Chen CJ 《Environmental health perspectives》2000,108(9):847-851
Diabetes prevalence in arseniasis-hyperendemic villages in Taiwan has been reported to be significantly higher than in the general population. The aim of this cohort study was to further evaluate the association between ingested inorganic arsenic and the incidence of non-insulin-dependent diabetes mellitus in these villages. A total of 446 nondiabetic residents in these villages were followed biannually by oral glucose tolerance test. Diabetes is defined as a fasting plasma glucose level > or = 7.8 mmol/L and/or a 2-hr post-load glucose level > or = 11.1 mmol/L. During the follow-up period of 1499.5 person-years, 41 cases developed diabetes, showing an overall incidence of 27.4/1,000 person-years. The incidence of diabetes correlated with age, body mass index, and cumulative arsenic exposure. The multivariate-adjusted relative risks were 1.6, 2.3, and 2.1 for age > or = 55 versus < 55 years, a body mass index ¿Greater/Equal to] 25 versus < 25 kg/m(2), and a cumulative arsenic exposure > or = 17 versus < 17 mg/L-years, respectively. The incidence density ratios (95% confidence intervals) between the hyperendemic villages and the two nonendemic control townships were 3.6 (3.5-3.6), 2.3 (1.1-4.9), 4.3 (2.4-7.7), and 5.5 (2.2-13.5), respectively, for the age groups of 35-44, 45-54, 55-64, and 65-74 years. The findings are consistent with our previous cross-sectional observation that ingested inorganic arsenic is diabetogenic in human beings. 相似文献
95.
96.
Breynia officinalis has the Chinese proprietary name, Chi R Yun, which means dizziness or vertigo for 7 d. In daily practice, it has been used to treat venereal diseases, contusion, heart failure, growth retardation and conjunctivitis in combination with other traditional Chinese medicines. Two hospital-based cases of Breynia officinalis poisoning have been reported to the Poison Control Center. Case 1 was a 43-y-old female who consumed a mixture of 1500 g lower stem and root of Ji Mu Ju in boiled water in a suicide attempt. Her AST reached 264 and ALT reached 2443. Case 2 was a 51-y-old female who consumed 20 pieces of lower stem and root of Ji Mu Ju stewed with meat and 100 ml of wine to treat chronic contact dermatitis. Her AST reached 3815 and ALT reached 6625. In both cases Breynia officinalis was identified as the cause of poisoning. Poisoning in humans involves the neurologic, gastrointestinal, hepatic, urinary and respiratory systems. Hepatotoxic effects have been reported for some Chinese herbal medicines, but not Breynia officinalis: Breynia officinalis poisoning causes hepatocellular liver injury rather than cholestatic liver injury. 相似文献
97.
98.
BACKGROUND/AIM: Uremic patients are at an increased risk of being affected by tuberculosis (TB). Periodical tuberculin skin tests were suggested to detect TB-infected patients. These were replaced by chest radiographs in endemic areas like Taiwan. However, almost 50% of the TB incidence in dialysis patients was extrapulmonary. In this study, we tried to investigate the value of tuberculin tests in dialysis patients in endemic areas. METHODS: The patients were recruited from our dialysis unit. Purified protein derivative (PPD) and control tests with antigens for Candida and toxoid were performed using the Mantoux method. PPD with >10-mm induration will be considered positive. Skin anergy meant that the indurations of all antigens were less than 5 mm. A follow-up was done 12 months after the tests. RESULTS: A total of 177 patients were evaluated. Anergy was found in 40 patients (22.6%). A positive predictor of anergy was age >45 years (p = 0.03), while a negative predictor was prealbumin >20 mg/dl (p = 0.04). Fifty-three patients (30%) had positive PPD tests. Seven of the positive PPD patients (13.2%) developed active TB during the following years. Among the 40 patients with skin anergy, 6 (15%) were found to have active TB. Of the 48 patients (21.1%) with indurations of the PPD tests between 5 and 10 mm, none was found to have active TB. CONCLUSION: Although anergy will influence the sensitivity of PPD tests, these tests in combination with anergy tests could help to establish the diagnosis of TB in uremic patients, even in TB-endemic areas. 相似文献
99.
BACKGROUND: This study evaluates the impact of free annual health examinations on survival of elderly (> or =65 years of age) residents in Kaohsiung City, Taiwan. METHODS: A stratified random sample scheme was used in each of the 11 districts of Kaohsiung City. A total of 1,193 elderly people were selected and interviewed in 1993; deaths and results of health check-ups were recorded through 1998. RESULTS: While over 50% of the subjects received at least one health examination between 1993 and 1998, only 18% received three or more. Most (60%) subjects who received examinations in a given year also received examinations the subsequent year; most (over 70%) who did not receive examinations in a given year did not receive check-ups the following year. Cox proportional hazards model showed that those who utilized the examination service had better survival probability than those who did not, given the same age, sex, education, marital status, living arrangements, and number of chronic diseases at baseline: The relative risk (RR) of mortality for those who ever utilized the health examination service was 0.50 (P < 0.0001). CONCLUSIONS: Elderly subjects who received annual health examinations had lower mortality than those who did not. This finding should be interpreted cautiously, however, as the difference in survival may reflect better general health behaviors among those who participated in the program. 相似文献
100.
A series of 4-(cyclic amido)-2H-naphtho[1,2-b]pyrans related to cromakalim (1) has been prepared and their vasorelaxant activities on isolated rat thoracic aorta precontracted with phenylephrine have been evaluated. The relaxant mechanism of 3a was found not through ATP-sensitive K(+) channels as cromakalim, but through opening voltage-sensitive K(+) channels. 相似文献