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61.
In potassium-depolarized guinea-pig left atria treated with isoproterenol, calcium entry blocking activities of adenosine and its potentiating compounds, dipyridamole, lidoflazine and dilazep were studied and compared to verapamil and diltiazem. pA2 values for various drugs were calculated using concentration-response curves for calcium (parallel shift to the right). The order of potency for the calcium entry blocking effect was: verapamil greater than diltiazem greater than adenosine greater than lidoflazine = dilazep greater than dipyridamole. Adenosine caused negative inotropic effects in depolarized left atria. The negative inotropic effect of adenosine was very quick in onset and was potentiated by erythro-6-amino-9(2-hydroxy-3-nonyl)-purine hydrochloride (EHNA), an adenosine deaminase inhibitor, suggesting that adenosine was being degraded. The effect of adenosine was quickly abolished by adenosine deaminase (ADA) and antagonized by 8-phenyltheophylline (8-PT), suggesting that the action of adenosine was most likely through the surface membrane receptor sites. The negative inotropic effects of dilazep and dipyridamole were only partially reversed by ADA and 8-PT, while that of lidoflazine was not affected by these agents. These findings suggest that the mechanism(s) of negative intotropic effect of lidoflazine was different from that of dilazep and dipyridamole. These data suggest that the negative intropic effect of dilazep is most likely due to a direct calcium entry blocking effect and in part due to its adenosine potentiating effect. However, the calcium entry blocking effect of lidoflazine is independent of adenosine. 相似文献
62.
Rizwan Azam Muhammad Rizwan Riaz Muhammad Umer Farooq Faraz Ali Muhammad Mohsan Ahmed Farouk Deifalla Abdeliazim Mustafa Mohamed 《Materials》2022,15(9)
In the past, many studies have been conducted on the optimization of reinforced concrete (RC) structures. These studies have demonstrated the effectiveness of different optimization techniques to obtain an economical design. However, the use of optimization techniques to an obtain economical design is not so practical due to the difficulty in applying most of the optimization techniques to achieve an optimal solution. The RC beam is one of the most common structural elements encountered by a practising design engineer. The current study is designed to highlight the potential of the Solver tool in MS Excel as an easy-to-use option for optimizing the design of simply supported RC beams. A user-friendly interface was developed in a spreadsheet in which beam design parameters from a typical design can be entered and an economical design can be obtained using the Evolutionary Algorithm available in the MS Excel Solver tool. To demonstrate the effectiveness of the developed optimization tool, three examples obtained from the literature have been optimized. The results showed that up to 24% economical solution can be obtained by keeping the same material strengths that were assumed in the original design. However, if material strength is also considered as a variable, up to 44% of the economical solution can be obtained. A parametric study was also conducted to investigate the effect of different design variables on the economical design of simply supported RC beams and to derive useful rules of thumb for their design and proportioning, with the objective of cost minimization. The results of the parametric study suggest that the grade of the reinforcing steel is one of the most influential factors that affect the cost of simply supported RC beams. Practicing engineers can use the trends derived from this research to further refine their optimal designs. 相似文献
63.
Evren Fidan Halil Kavgaci Asim Orem Mustafa Yilmaz Bulent Yildiz Sami Fidan Buket Akcan Feyyaz Ozdemir Fazil Aydin 《Tumour biology》2012,33(5):1519-1525
The relation between cancer and coagulation is the subject of investigation since a relation between tumor and thrombosis has been determined. Antithrombin III is an important thrombin inhibitor, and increased thrombin?Cantithrombin (TAT) complex levels activate coagulation. Activated thrombin activatable fibrinolysis inhibitor (TAFI) inhibits the conversion of plasminogen to plasmin. In addition, it directly inactivates plasmin. Defective fibrinolysis increases the risk of thrombosis. In this study, we evaluated homeostatic parameters, TAFI, and TAT levels in patients with gastric cancer applying to the medical oncology outpatient clinic. Fifty-two patients and 35 healthy controls were included. ELISA was used to measure TAFI and TAT complex levels. These were statistically higher in the patient group (p?<?0.05 and p?=?0.001, respectively). D-dimer levels were higher in stage IV (p?=?0.05). Correlations between lymph nodes and TAFI and TAT levels were examined. Weak but positive correlation between lymph nodes and TAFI was detected (R?=?0.452, p?=?0.027). TAFI and TAT levels were evaluated using relative operating characteristic analysis to differentiate the disease. TAT was more specific than TAFI according to this analysis (TAFI area under curve (AUC), 0.676; TAT AUC, 0.874). Thrombotic events and bleeding disorders need to be borne in mind in gastric cancer. This situation is due to the impairment of the balance between coagulation and fibrinolysis. Further studies are now needed to evaluate the effects of TAFI and TAT on survey and prognosis as well as the potential of these parameters as tumor markers for gastric cancer. 相似文献
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66.
PURPOSEAlthough imaging-guided core needle breast biopsy is a minimally invasive diagnostic procedure, it is reported that patients may experience anxiety and pain. Interventions to reduce anxiety are important for high quality health services during imaging-guided core needle breast biopsy. The purpose of this study was to evaluate the effect of music intervention on anxiety and pain levels of patients undergoing ultrasound-guided core needle breast biopsy.METHODSIn a prospective randomized controlled design, patients who were referred for ultrasound-guided core needle breast biopsy were invited to the study and randomized into the intervention group who received standard care with classical music intervention before and during the biopsy procedure, and the control group who received only standard care. Both groups received local anesthesia. The Spielberger State-Trait Anxiety Inventory and the Visual Analogue Scale (VAS) were used for measuring anxiety and pain levels after the procedure. One-way multivariate analysis of variance test was used to find the effect of music intervention on patient anxiety and pain.RESULTSThere were 31 patients (48.4%) in the intervention group and 33 (51.6%) in the control group; the groups were similar in terms of sociodemographic characteristics and general (trait) anxiety levels. The patients in the music intervention group had significantly lower state anxiety score than the control group (p = 0.008) with a mean difference of 3.8 (95% CI, 1.0–6.6). The mean difference of VAS pain score was 6.0 (95% CI, 2.2–14.2), which not statistically significant between groups (p = 0.150). There was no significant correlation between the VAS and the state anxiety scale (r = 0.003, p = 0.980).CONCLUSIONMusic reduced anxiety, but not pain during ultrasound-guided core needle breast biopsy. These results have implications especially for low and middle-income countries where low-cost and easily implemented interventions are needed to address patient anxiety during breast biopsy procedures.Imaging-guided core needle breast biopsy is a safe and cost-effective procedure that is essential for managing suspicious breast lesions (1, 2). Although imaging-guided core needle breast biopsy is a minimally invasive procedure, patients may experience anxiety and distress (3). Reducing anxiety during biopsy procedures is important as higher anxiety during different biopsy procedures was found to be associated with higher pain (4, 5), and reducing anxiety may reduce the pain and increase the patient comfort. Furthermore, the regulation of anxiety during breast biopsy plays an important role in adherence to follow-up (6).Music regulates emotions by affecting the expression of opiate, nitric oxide, cytokine, and hormone levels through neuroendocrinological pathways (7). Music has been shown to reduce anxiety and pain levels in different medical procedures like chemotherapy, chest tube removal, endoscopy, colonoscopy, magnetic resonance imaging, fine needle aspiration biopsy, transrectal ultrasound-guided prostate biopsy, bone marrow biopsy, surgery, labor and caesarian section (8–11). A systematic review recommended that music intervention should be applied to clinical management of biopsy patients (12). However, there is scarce research on the effect of music on ultrasound-guided core needle breast biopsy patients’ anxiety and pain levels (13–15). Two of these trials showed that music reduced the anxiety levels of breast biopsy patients (13, 15), whereas one study reported that music intervention was not effective (14). All of the mentioned studies are from high income countries and have inconsistent results. There is no study on the effect of music intervention on anxiety and pain levels of ultrasound-guided core needle breast biopsy patients from low- and middle-income countries where there may be cultural and socioeconomical differences that may affect the patients’ response to music interventions. Furthermore, these countries are in need of low-cost interventions to increase the quality of life of patients.This study investigated whether or not classical music changed patient anxiety and/or pain levels of patients undergoing ultrasound-guided core needle breast biopsy in Turkey. It was hypothesized that music intervention will decrease the patients’ anxiety and pain levels. 相似文献
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Fahrettin Yildiz Alpaslan Terzi Sacid Coban Hakim Celik Nurten Aksoy Muharrem Bitiren Hale Çakir Mustafa K Ozdogan 《Journal of gastroenterology and hepatology》2009,24(11):1781-1785
Background and Aim: The aim of this study was to determine whether resveratrol could prevent intestinal tissue injury induced by ischemia–reperfusion (I/R).
Methods: Intestinal I/R was induced in rats' intestines by 60-min occlusion of the superior mesenteric artery, followed by a 60-min reperfusion. Thirty rats were divided into three groups as follows: sham (group 1), control (group 2), and the treatment groups (group 3). The rats in the treatment group received resveratrol both before ischemia and before reperfusion. In all groups, serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase levels were determined. Total antioxidant capacity (TAC), catalase, total oxidative status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) in the intestinal tissue were measured. Intestinal tissue histopathology was also evaluated by light microscopy.
Results: The levels of liver enzymes in group 3 were significantly lower than those in group 2 ( P < 0.05). TAC in the intestinal tissue was significantly higher in group 3 than in group 2 ( P < 0.05). TOS, OSI, and MPO in the intestinal tissue were significantly lower in group 3 than in group 2 ( P < 0.05 for all). Histological tissue damage was milder in the resveratrol treatment group than in the control group.
Conclusions: The results of this study indicated that resveratrol treatment limits the oxidative injury of the small intestine induced by I/R in rats. However, more precise investigations are required to evaluate the antioxidative effect of resveratrol on small intestine tissue damage in clinical and experimental models. 相似文献
Methods: Intestinal I/R was induced in rats' intestines by 60-min occlusion of the superior mesenteric artery, followed by a 60-min reperfusion. Thirty rats were divided into three groups as follows: sham (group 1), control (group 2), and the treatment groups (group 3). The rats in the treatment group received resveratrol both before ischemia and before reperfusion. In all groups, serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase levels were determined. Total antioxidant capacity (TAC), catalase, total oxidative status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) in the intestinal tissue were measured. Intestinal tissue histopathology was also evaluated by light microscopy.
Results: The levels of liver enzymes in group 3 were significantly lower than those in group 2 ( P < 0.05). TAC in the intestinal tissue was significantly higher in group 3 than in group 2 ( P < 0.05). TOS, OSI, and MPO in the intestinal tissue were significantly lower in group 3 than in group 2 ( P < 0.05 for all). Histological tissue damage was milder in the resveratrol treatment group than in the control group.
Conclusions: The results of this study indicated that resveratrol treatment limits the oxidative injury of the small intestine induced by I/R in rats. However, more precise investigations are required to evaluate the antioxidative effect of resveratrol on small intestine tissue damage in clinical and experimental models. 相似文献
69.
Karti SS Ovali E Ozgur O Yilmaz M Sonmez M Ratip S Ozdemir F 《Hepato-gastroenterology》2003,50(54):1864-1866
BACKGROUND/AIMS: Apoptotic and anti-proliferative effects of heparin on a number of cancers have been described. There have been no studies analyzing the effect of heparin on human hepatoma cells. The aim of this study was to investigate the effect of heparin on human hepatoma cell line, HepG2. METHODOLOGY: HepG2 cell line was cultured with different concentrations of heparin. Colony count, viability assay, percentage of the apoptosis and proliferative index were assessed at the end of the 7th day. Trypan blue was used to assess viability. Apoptosis and proliferative indexes were assessed by flow-cytometry. RESULTS: Hepatoma cells were arrested at the G0/G1 phase with heparin incubation and proliferative indexes decreased significantly in 20, 40 and 80 U/mL of heparin concentrations in comparison with the control (36 +/- 1%, 30 +/- 5% and 29 +/- 8% vs. 44 +/- 1%, p < 0.01). Flow cytometry revealed a statistically significant increase in apoptosis in groups incubated with 40 and 80 U/mL of heparin in comparison with the control (39 +/- 26% and 58 +/- 18% vs. 0.83 +/- 1.3%, p < 0.01). Colony counts per well and viable cells per microL decreased significantly in 80 U/mL of heparin. CONCLUSIONS: Heparin leads to a significant anti-proliferative and an apoptotic effect on human hepatoma cells in vitro. 相似文献
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