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991.
ABSTRACT

Objective: This study aimed to understand the usage patterns and correlates of illicit drug use among schoolchildren in Colombo district, Sri Lanka. Methods: A cross-sectional study was carried out among grade 10 and 12 students using a self-administered questionnaire. Results: From the 6000 students selected, 5353(89.22%) responded. Betel chewing with tobacco was seen in 28.48% males and 10.44% females. Substances such as Barbul, Madana Modaka, and cough syrups that are not established as illicit drugs were used as psychoactive substances. Ingredients of some of these compounds are not fully understood or regulated. Prevalence of cannabis use was 3.85% in males and 0.24% in females. Studying nonscience subjects for Advanced Level, doing sports, low academic performance, and peer smoking significantly increased the odds of using one or more substances (P < .05). Conclusions: Many types of illicit substances were used by schoolchildren. More strategies to prevent further aggravation of these behaviors are needed. Constituents of some compounds are not understood and need further evaluation. Recognized high-risk groups can be targets for preventive and cessation programs.  相似文献   
992.
Background: Aluminum (Al) contamination of parenteral nutrition (PN) solutions remains a concern for long‐term PN patients. Al accumulates particularly in bone. Excessive exposure to Al may result in increased Al body burden and impaired bone formation and mineralization, leading to bone disease. Although the U.S. Food and Drug Administration (FDA) has limited Al contamination in large‐volume parenteral solutions, small‐volume parenterals may still contribute considerable amounts of Al to PN solutions. The goal of this study is to determine whether or not long‐term adult PN patients remain at risk for increased bone Al accumulation. Methods: We measured Al accumulation in autopsy bones from 7 patients who had received PN for 2–21 years and compared bone Al levels with those in living control patients undergoing hip or knee replacement. Electrothermal atomic absorption spectrometry was used for bone Al measurements. Results: When compared with bone Al content in controls, markedly elevated Al levels (P < .0001) were found in the bones of all but 1 patient, who received PN for only 2 years before death. Even greater Al accumulation was found for PN patients who developed late renal impairment (P = .0159). Conclusions: We conclude that long‐term adult PN patients continue to be at risk for Al toxicity.  相似文献   
993.
目的 比较常用的3种检测单纯疱疹性角膜炎(HSK)辅助诊断方法的敏感性和临床实用性。方法6只新西兰白兔双眼接种1×105PFU单纯疱疹病毒I型(HSV-I)McKrea株。病毒接种后第8天应用无环鸟苷眼膏每2 h 1次,共4次。另外2只兔中1只兔双眼在角膜上划痕但不接种病毒,另1只兔双眼角膜接种曲霉菌作为阴性对照。在病毒接种后的3、9、21天,利用病毒分离、多聚酶链反应(PCR)和蛋白吸附膜快速单纯疱疹病毒I型抗原检测方法进行检测。结果 接种后第2天全部角膜出现典型的HSK点状或树枝状浸润,第5天出现地图状溃疡,第21天仍有2只角膜有持续性感染。抗病毒治疗1天后无明显好转。2只兔于接种后14和16天死亡。病毒分离方法只有接种后3天的泪液培养阳性,第9、21天的标本检测均为阴性。有11/12、11/12和6/8只角膜在接种后的第3、9、21天用PCR方法检测到了HSV-I DNA。蛋白吸附膜抗原检测在接种后的第3、9、21天的阳性率分别为12/12、12/12和3/8。结论 蛋白吸附膜快速HSV—I检测是一种快速、简便、经济的方法。其阳性结果与临床表现相吻合。  相似文献   
994.
995.

Background and purpose:

Checkpoint kinase 2 (CHK2) is activated by DNA damage and can contribute to p53 stabilization, modulating growth arrest and/or apoptosis. We investigated the contribution of CHK2 to oxaliplatin-mediated toxicity in a colorectal cancer model.

Experimental approach:

We evaluated the ability of CHK2 small molecule inhibitors to potentiate oxaliplatin-induced toxicity. The role of CHK2 in oxaliplatin-induced apoptosis was investigated in HCT116 cells that were wild-type (WT) or KO for CHK2. Small molecule inhibitors of CHK2 were used in combination studies with oxaliplatin in this cell model.

Key results:

In oxaliplatin-treated CHK2 KO cells, accelerated apoptosis was accompanied by attenuated p53 stabilization and p21WAF-1 up-regulation correlating with increased Bax expression, cytochrome c release and elevated caspase activity. The higher levels of apoptosis in CHK2 KO cells were restored to control (WT) levels when CHK2 was re-introduced. This ‘uncoupling’ of p53 stabilization and Bax up-regulation in CHK2 KO cells suggested oxaliplatin-induced apoptosis was due to a p53-independent response. Combination studies revealed that CHK2 inhibitor II or debromohymenialdisine antagonized the responses to oxaliplatin. This inhibitory effect correlated with decreases in apoptosis, p53 stabilization and DNA inter-strand cross-link formation, and was dependent on the presence (but not activity) of CHK2.

Conclusions and implications:

Combinations of CHK2 inhibitors with oxaliplatin should further sensitize cells to oxaliplatin treatment. However, these inhibitors produced an antagonistic effect on the response to oxaliplatin, which was reversed on the re-introduction of CHK2. These observations may have implications for the use of oxaliplatin in colorectal cancer therapy in combination with therapies targeting CHK2.  相似文献   
996.
OBJECTIVE: To explore the expectations of patients and parents of children with asthma regarding access to complementary therapies via the NHS. METHODS: Fifty semi-structured interviews with adults and parents of children with asthma, from a range of health-care settings, including users and non-users of complementary therapies. Interviews were recorded, transcribed verbatim and the data were analysed thematically. RESULTS: Thirty-one patients were using complementary therapies for asthma, six were using complementary therapies for other health problems and 13 were non-users. Various therapies were used for asthma, most commonly homeopathy and breathing techniques, predominantly outside the NHS. Two broad themes emerging from the data were expectations about access to information and knowledge about complementary therapies via NHS health professionals, and expectations regarding access to complementary therapy services via the NHS. As a minimum, the majority of participants wanted NHS health professionals to be more 'open' towards and know more about complementary therapies than their patients - perceived as not currently usual. Most were positive about greater NHS access to complementary therapy services, for enhancing patient choice, improving equality in access for less affluent patients and facilitating patients' self-help. Participants who were highly sceptical about complementary therapies argued that lack of scientific evidence of effectiveness prohibited the need for greater complementary therapy knowledge or service provision within the NHS. Alongside their expectations, patients and parents expressed realistic views about facilitators and barriers to greater access. CONCLUSIONS: While health service planners and providers often express reservations about the value of complementary therapies, it is important to take patients' preferences into account if policy discourses regarding patient-centred care and choice are to be realized in practice.  相似文献   
997.
998.
近年来,随着临床经验的不断积累,学者们发现RouxY吻合术后,相当一部分患者出现饭后上腹饱胀、腹痛、恶心、呕吐,重者发生营养不良,胃粪石形成等.这组症状称为胃切除术后RouxY滞留综合征(RouxYstasissyndromeaftergast...  相似文献   
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1000.
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