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991.
We have, whenever possible, substituted cryoablation for incisions in the maze procedure. Cryoablation helps prevent massive bleeding because the number of resuturing sites is reduced and aortic cross-clamp time decreased. We are careful not to injure the atrio-ventricular conduction system during incision at the side of the Koch triangle or cryoablation while manipulating the atrial septum. In prior versions of the right-sided maze procedure, the IVC return cannula has obstructed the surgical field approaching the IVC and the tricuspid valve annulus. This report describes a new modification of maze procedure that includes changing the venous return site. We have obtained a satisfactory surgical field without being afraid of the anatomical pitfall, between the appendage and the tricuspid valve, and between the right coronary artery and the extended T incision. We studied 12 patients (8 males and 4 females, mean age 61 years) who underwent the maze procedure. Sinus rhythm was restored in 11 patients, whose clinical condition was improved to NYHA class I status. This technique has proven effective in obtaining satisfactory exposure of the-right atrium during the maze procedure.  相似文献   
992.
We report a case of pulmonary cryptococcosis diagnosed by video-assisted thoracoscopic surgery (VATS) with CT-guided localization. A 61-year-old man was admitted to our hospital for the precise diagnosis of a solitary mass in the left upper lung. Because the mass was too small to be detected under VATS, we tried CT-guided localization for surgery. One day before VATS, we placed a marking device besides the lesions after percutaneous puncture. We used a Naruke point marker as a marking device. After this procedure, the wedge resection was performed. The pathological diagnosis was cryptococcosis of the lung. The identification of small lesions in the lung has frequently been detected by helical and thin slice CT. Therefore, CT-guided localization procedure may be the most reliable technique to employ before surgery.  相似文献   
993.
994.
Metallothionein-inducing activities of 11 saponins were investigated in mice. Of the saponins investigated, echinoside A and sakuraso-saponin were highly effective. Sakuraso-saponin showed dose-dependent and time-dependent induction of hepatic metallothionein. The isoforms of the induced metallothionein in the liver were determined to be metallothionein 1 and 2. Induction of metallothionein was observed specifically in the liver and heart. Echinoside A showed similar effects to sakuraso-saponin except that no induction was observed in the heart. Pretreatment of mice with these saponins blocked CCl4-induced hepatic injury, such as the elevation of plasma transaminase activity and centrilobular necrosis in the liver. CCl4-induced elevation of lipid peroxide level in the liver was also blocked by injection of sakuraso-saponin. The hepatoprotective activities of the saponins found in this study may have been due to their MT-inducing activity. © 1997 by John Wiley & Sons, Ltd.  相似文献   
995.
Pt is an excellent and widely used hydrogen evolution reaction (HER) catalyst. However, it is a rare and expensive metal, and alternative catalysts are being sought to facilitate the hydrogen economy. As tungsten carbide (WC) has a Pt-like occupied density of states, it is expected to exhibit catalytic activity. However, unlike Pt, excellent catalytic activity has not yet been observed for mono WC. One of the intrinsic differences between WC and Pt is in their magnetic properties; WC is non-magnetic, whereas Pt exhibits high magnetic susceptibility. In this study, the WC lattice was doped with ferromagnetic Co nanocrystals to introduce an ordered-spin atomic configuration. The catalytic activity of the Co-doped WC was ∼30% higher than that of Pt nanoparticles for the HER during the hydrolysis of ammonia borane (NH3BH3), which is currently attracting attention as a hydrogen fuel source. Measurements of the magnetisation, enthalpy of adsorption, and activation energy indicated that the synergistic effect of the WC matrix promoting hydrolytic cleavage of NH3BH3 and the ferromagnetic Co crystals interacting with the nucleus spin of the protons was responsible for the enhanced catalytic activity. This study presents a new catalyst design strategy based on the concept of an internal magnetic field. The WC–Co material presented here is expected to have a wide range of applications as an HER catalyst.

The catalytic activity of the Co-doped WC is 30% higher than that of Pt nanoparticles for the hydrogen evolution reaction arising from an internal magnetic field.  相似文献   
996.
Objectve To assess the impact of glycemic variability on blood pressure in hospitalized patients with cardiac disease. Methods In 40 patients with cardiovascular disease, the glucose levels were monitored by flash continuous glucose monitoring (FGM; Free-Style Libre™ or Free-Style Libre Pro; Abbott, Witney, UK) and self-monitoring blood glucose (SMBG) for 14 days. Blood pressure measurements were performed twice daily (morning and evening) at the same time as the glucose level measurement using SMBG. Results The detection rate of hypoglycemia using the FGM method was significantly higher than that with the 5-point SMBG method (77.5% vs. 5.0%, p<0.001). Changes in the systolic blood pressure from evening to the next morning [morning - evening (ME) difference] were significantly correlated with night glucose variability (r=0.63, P<0.001). A multiple regression analysis showed that night glucose variability using FGM was more closely correlated with the ME difference [r=0.62 (95% confidence interval, 0.019-0.051); p<0.001] than with the age, body mass index, or smoking history. Night glucose variability was also more closely associated with the ME difference in patients with unstable angina pectoris (UAP) than in those with acute myocardial infarction (AMI) or heart failure (HF) (r=0.83, p=0.058). Conclusion Night glucose variability is associated with the ME blood pressure difference, and FGM is more accurate than the 5-point SMBG approach for detecting such variability.  相似文献   
997.
998.
BACKGROUND: The pharmacologic response and microvascular effects associated with the endoscopic injection of sclerosing agents around vessels (paravascular injection) to stop bleeding from the digestive tract remain to be clarified. METHODS: Using in vivo microscopy, we directly visualized submucosal microvessels of the rat stomach and intestine. We studied differences among sclerosing agents in thrombus formation and vascular diameter change that occur through a pharmacologic response and/or local compression after topical application or paravascular injection of the agents. RESULTS: Except for absolute ethanol, topical application of the agents did not cause constriction or thrombi in either arterioles or venules. Polidocanol topical application and paravascular injection significantly dilated arterioles. Injecting ethanolamine oleate near venules constricted them the longest and most effectively, but vasoconstriction in arterioles was transient. Injecting absolute ethanol formed long-lasting thrombi and caused vasoconstriction in venules, but arteriole thrombi persisted no more than 3 minutes. The vascular response to thrombin did not significantly differ from that to physiologic saline. CONCLUSION: The paravascular injection of ethanolamine oleate, because of its long-lasting vasoconstriction, or of absolute ethanol, because of its thrombogenic effect, is a valid therapeutic approach to treating venous bleeding. The efficacy of paravascular injection of sclerosing agents for treating acute arterial bleeding, however, is not supported in this experimental model.  相似文献   
999.
Summary We report a case of acute pancreatitis complicating Salmonella enteritis. A 43-yr-old woman who was admitted to our department because of Salmonella enteritis developed clinical acute pancreatitis with laboratory and radiographic signs on the fourth hospital day. She was free from symptoms on the eighth hospital day, but her elevated serum amylase and lipase levels persisted for more than 2 mo. In this case, clinical acute pancreatitis was a complication of bacterial enteritis caused by Salmonella enteritidis, and it was characterized by onset a few days after the onset of enteritis and by sustained elevation of serum pancreatic enzyme levels.  相似文献   
1000.
Objective: We conducted a randomized controlled trial to compare the efficacy of two different dosages of lymphoblastoid interferon α (IFN) for the treatment of chronic hepatitis C. Methods: Eighty-four patients with chronic hepatitis C were enrolled and randomly assigned into the two groups; group A was treated with 6 million units (MU) and group B with 9 MU daily for the first 2 wk, and then thrice weekly for an additional 14 or 22 wk. Results: Eighty patients were evaluated (39 patients in group A and 41 in group B); 14 patients in group A (35.9%) and 15 in group B (36.6%) obtained sustained response. The percentages of patients who became negative for HCV RNA at the end of the second wk differed slightly between the groups, without statistical significance (56.4% and 68.3%). When assessed in detail, patients with genotype 1 and < 1 Meq/ml of viral load became negative for HCV RNA significantly more frequently in group B (eight of eight) than in group A (three of seven) (   p < 0.05  ) at the end of the second week, whereas the sustained response rate was similar between the groups (five of eight and four of seven). Predictors of sustained response by multivariate analysis were low viral load (< 1.0 Meq/ml) and negativity of HCV RNA at the end of the second wk of IFN. Conclusions: The results indicated that there was no difference in sustained response rate between the 6-MU and 9-MU doses. The earlier disappearance of HCV RNA, at the end of the second wk or at least by the end of the fourth week, is an essential condition for sustained response.  相似文献   
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