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Cholinesterases, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), have a role in cholinergic deficit which evidently leads to Alzheimer's disease (AD). Inhibition of cholinesterases with small molecules is an attractive strategy in AD therapy. This study demonstrates synthesis of pyrido[2,3‐b]pyrazines ( 6a ‐ 6q ) series, their inhibitory activities against both cholinesterases, AChE and BChE, and molecular docking studies. The bioactivities data of pyrido[2,3‐b]pyrazines showed 3‐(3′‐nitrophenyl)pyrido[2,3‐b]pyrazine 6n a potent dual inhibitor among the series against both AChE and BChE with IC50 values of 0.466 ± 0.121 and 1.89 ± 0.05 μm , respectively. The analogues 3‐(3′‐methylphenyl)pyrido[2,3‐b]pyrazine 6c and 3‐(3′‐fluorophenyl)pyrido[2,3‐b]pyrazine 6f were found to be selective inhibition for BChE with IC50 values of 0.583 ± 0.052 μm and AChE with IC50 value of 0.899 ± 0.10 μm , respectively. Molecular docking studies of the active compounds suggested the putative binding modes with cholinesterases. The potent compounds among the series could potentially serves as good leads for the development of new cholinesterase inhibitors.  相似文献   
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A new phenylpropanoid glycoside, dolichandroside‐A, together with seven known compounds α‐lapachone, lapachol, aloesaponarin II, 8‐hydroxydehydroiso‐α‐lapachone, β‐sitosterol, 3,8‐dihydroxydehydroiso‐α‐lapachone and verbascoside were isolated from the active ethyl acetate soluble extract of heartwood of Dolichandrone falcata. All except for dolichandroside‐A are known compounds, but have been isolated for the first time from this plant. The structure of all these compounds was determined on the basis of 1D‐ and 2D‐NMR spectral data. All the isolates were tested for α‐glucosidase inhibitory and DPPH radical scavenging activity. This is the first report identifying DPPH scavenging activity and α‐glucosidase inhibitory activity in D. falcata. Furthermore, along with a new compound, dolichandroside‐A, this study also assigns for the first time α‐glucosidase inhibitory activity to verbascoside and aloe saponarin‐II. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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It is not always possible to achieve a successful induction. Bishop scoring system is an efficient method used in determining whether the induction will be effective or not. The aim of this study was to train midwives on the benefits and use of the Bishop scoring system and to minimize the unnecessary use of induction. This study was conducted as pretest–posttest quasi‐experimental design. This study was conducted in a maternity hospital in Erzurum between 01 February and 31 July 2012. In the study, the midwives received training on the use of the Bishop scoring system, and changes in their knowledge levels and application during practice of induction were then evaluated. While only 20% of midwives were using the Bishop score before the training, 56.7% started to use this tool after the training. Comparing the examinations performed on pregnant women by the midwives in the pre‐induction period before and after the training, the mean of the Bishop score changed from 7.26 to 9.68 after the training. It was determined that the training could increase the knowledge levels of midwives regarding the Bishop scoring system and their attention paid to the Bishop scoring system in the practice of induction.  相似文献   
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The quality of sexual life is based on a physical, relational, and emotional assessment of an individual. This study aimed to analyze the relationship between sexual quality of life, happiness, and satisfaction with life. The research comprised of 204 women, aged between 18 and 63. The average age of participants was 31.98. In this study, the sexual quality of life questionnaire-female, Oxford happiness questionnaire-short form, and satisfaction with life scale were used as data collection tools. The findings indicated that the sexual quality of life in women has a positive relationship with happiness and satisfaction with life. Therefore, sexual quality of life is a significant predictor of happiness and satisfaction with life. It also explains 19 % of the variance concerning happiness and 25 % of the variance regarding satisfaction with life. As a result, the findings obtained from the present study show that the sexual quality of life in women is important in relation to happiness and satisfaction with life.  相似文献   
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Until last the decade, the renin-angiotensin system (RAS) was considered as a circulating endocrine system. It is now known that there are local RASs in many tissues. It has also recently been hypothesized that there exists a local bone marrow (BM) RAS with paracrine/autocrine pathobiological functions. The aim of this study was to detect BM and peripheral blood levels of the essential RAS components in normal and leukemic hematopoiesis. Concentrations of renin and angiotensin-converting enzyme (ACE) were assayed in BM aspirates and in simultaneously drawn peripheral blood samples of 16 pre-chemotherapy leukemic and 10 post-treatment megaloblastic anemia patients with normal blood counts, as controls. In the leukemia group, the ACE concentration was found to be significantly higher in the BM (38+/-6.2 U/l) than in the peripheral blood (29.5+/-5.3 U/l), (p=0.029). In the leukemia group, although the BM renin concentration was higher than the peripheral blood levels (21.3+/-8.3 vs. 18.6+/-6.2 U/l), this difference was not statistically significant (p=0.196). In the control group, mean BM renin levels were insignificantly lower than in the peripheral blood (8.6+/-3 vs. 12.1+/-4.6 pg/ml) (p=0.059). In the leukemia group, serum ACE levels positively correlated with BM and peripheral blood blast percentages (p<0.05). Serum LDH level (p<0.01), BM blast (p<0.05) and peripheral blast percentages (p<0.01) were inversely correlated with serum potassium in the leukemia group.The results of this study can be considered as the preliminary evidence supporting the hypothesis of the presence of a local BM RAS. Further, molecular biologic and immunohistochemical studies are needed to shed light on this important subject. A better understanding of the interrelationships of RAS and hematopoiesis will bring new insights into the pathobiology and even novel therapies for such neoplastic diseases.  相似文献   
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BACKGROUND: The pathogenic role of TT virus (TTV) is not clear in patients with chronic hepatitis B. The aims of the present study were to determine the frequency of TTV positivity in serum and saliva samples and the possible role of TTV in children with chronic hepatitis B. METHODS: Sera and saliva from 29 healthy children and 25 children with chronic hepatitis B were tested for TTV-DNA by means of real-time polymerase chain reaction (PCR). RESULTS: Fifty-two percent (13/25) of the serum samples and 32% (8/25) of the saliva samples were positive for TTV-DNA in children with chronic hepatitis B. In healthy non-transfused children, TTV-DNA was detected in 58% (17/29) of the serum samples and 41% (12/29) of the saliva samples. Six (46%) of 13 children with chronic hepatitis and 10 (59%) of 17 healthy children had TTV-DNA positivity both in serum and saliva samples. Two serum samples were negative for TTV-DNA while the saliva samples were positive for TTV-DNA in chronic hepatitis B and control groups. Mean age, sex, serum alanine aminotransferase levels, hepatitis B virus (HBV)-DNA values were similar in TTV-positive and -negative children with chronic hepatitis B. However, total histologic activity index (HAI), periportal necrosis and portal inflammation scores were significantly higher in children with HBV-DNA and TTV-DNA viremia (P = 0.013, P = 0.008, P = 0.015, respectively). CONCLUSIONS: Because total HAI, periportal necrosis and portal inflammation scores were higher in children with TTV coinfection, TTV infection may contribute to the progression of liver damage in children with chronic hepatitis B.  相似文献   
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