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71.
The recent surge in injection drug use (IDU) in Prague, Czech Republic, provided an opportunity to compare the distribution of hepatitis C virus (HCV) genotypes among recent injection drug users and nonusers. We provide evidence that the most common HCV subtype, 1b, has been circulating in Prague longer than the other subtypes but that IDU practice has magnified its recent prevalence, and that the primary drug of choice among IDU subjects appears to influence the prevalence of a particular HCV subtype.  相似文献   
72.

Objectives

The REAC-TAVI (Assessment of platelet REACtivity after Transcatheter Aortic Valve Implantation) trial enrolled patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) pre-treated with aspirin + clopidogrel, aimed to compare the efficacy of clopidogrel and ticagrelor in suppressing high platelet reactivity (HPR) after TAVI.

Background

Current recommendations support short-term use of aspirin + clopidogrel for patients with severe AS undergoing TAVR despite the lack of compelling evidence.

Methods

This was a prospective, randomized, multicenter investigation. Platelet reactivity was measured at 6 different time points with the VerifyNow assay (Accriva Diagnostics, San Diego, California). HPR was defined as (P2Y12 reaction units (PRU) ≥208. Patients with HPR before TAVR were randomized to either aspirin + ticagrelor or aspirin + clopidogrel for 3 months. Patients without HPR continued with aspirin + clopidogrel (registry cohort). The primary endpoint was non-HPR status (PRU <208) in ≥70% of patients treated with ticagrelor at 90 days post-TAVR.

Results

A total of 68 patients were included. Of these, 48 (71%) had HPR (PRU 273 ± 09) and were randomized to aspirin + ticagrelor (n = 24, PRU 277 ± 08) or continued with aspirin + clopidogrel (n = 24, PRU 269 ± 49). The remaining 20 patients (29%) without HPR (PRU 133 ± 12) were included in the registry. Overall, platelet reactivity across all the study time points after TAVR was lower in patients randomized to ticagrelor compared with those treated with clopidogrel, including those enrolled in the registry (p < 0.001). The primary endpoint was achieved in 100% of patients with ticagrelor compared with 21% with clopidogrel (p < 0.001). Interestingly, 33% of clopidogrel responder patients at baseline developed HPR status during the first month after TAVR.

Conclusions

HPR to clopidogrel is present in a considerable number of patients with AS undergoing TAVR. Ticagrelor achieves a better and faster effect, providing sustained suppression of HPR to these patients. (Platelet Reactivity After TAVI: A Multicenter Pilot Study [REAC-TAVI]; NCT02224066)  相似文献   
73.
74.
INTRODUCTION AND OBJECTIVES: Five percent of the patients with hypertrophic obstructive cardiomyopathy (HOCM) have symptoms unresponsive to medical treatment and are candidates for invasive therapy. The objective of this study was to analyze our results with surgical treatment of HOCM during the last 10 years. PATIENTS AND METHOD: Between July 1993 and January 2004 26 patients with HOCM refractory to drug therapy were operated on. An extended septal myectomy was performed, in combination with anterior mitral leaflet plication in 19 cases (73%) and with mitral valve replacement in 5 (19%). Evolution of the grade of dyspnea, left ventricle outflow tract gradient (LVOTG), mitral regurgitation, and systolic anterior motion after surgery was analyzed. RESULTS: Mean follow-up was 63 (37) months. After surgery, a significant reduction in LVOTG (from 96.5 to 19.5 mmHg; P<.001), grade of mitral regurgitation (from 2.54 to 0.69; P<.001) and systolic anterior motion (from 2.92 to 0.23; P<.001) was achieved, which led to improvement in functional class. Hospital mortality and need for pacemaker implantation due to complete heart block after surgery was 3.8% (n=1). There were no cases of iatrogenic ventricular septal defect or mitro-aortic valve injury. Actuarial survival at 5 years was 96% (4%). CONCLUSIONS: Surgery in patients with HOCM yields great clinical improvements with low morbidity and mortality. Simultaneous intervention for both myocardial and valvular components of the disease allows not only reduction in the LVOTG but also correction of mitral regurgitation and abolition of systolic anterior motion.  相似文献   
75.
Robotic and Laparoscopic Surgery for Treatment of Colorectal Diseases   总被引:8,自引:0,他引:8  
PURPOSE In the last ten years, several robotic systems have been developed to overcome the loss of the three-dimensional view and dexterity characteristic of laparoscopic surgery. The aim of this study was to compare the traditional laparoscopic approach and robotic techniques in the treatment of colorectal diseases.METHODS The study compares a consecutive series of patients treated surgically for colorectal disease from June 2001 to May 2003 with the da Vinci robotic system (Intuitive Surgical®) and a matched number of patients who underwent conventional laparoscopy during the same time interval. The factors analyzed were the time required to prepare the patient and the room, total time of surgery, length of specimens, number of lymph nodes retrieved, blood loss, complications, and postoperative results.RESULTS The study included 106 patients (53 in each group). No differences were observed in total time of surgery (laparoscopic group, 222 ± 77 minutes vs. robotic group, 240 ± 61 minutes), specimen length (laparoscopic group, 29 ± 11 cm vs. robotic group, 27 ± 13 cm), or number of lymph nodes retrieved (laparoscopic group, 16 ± 9 vs. robotic group, 17 ± 10). It took significantly longer to prepare the operating room and patient in the robotic group (24 ± 12 minutes) than in the laparoscopic group (18 ± 7 minutes). There were three conversions to laparotomy in the laparoscopic group; in the robotic group, two cases were converted to laparoscopy and three to hand-assisted laparoscopy. No significant differences were observed between the two groups in terms of recovery of bowel function and postoperative hospital stay.CONCLUSIONS Robot-assisted surgery proved to be as safe and effective as laparoscopic techniques in the treatment of colorectal diseases. Because of its dexterity and three-dimensional view, the da Vinci system was particularly useful in specific stages of the procedure, e.g., takedown of the splenic flexure, dissection of a narrow pelvis, identification of nervous plexus, and handsewn anastomosis. The cost-effectiveness of the procedure still needs to be evaluated.  相似文献   
76.
OBJECTIVES: To understand the role of Gemella species as a pathogen causing extra-abdominal infections in the Hospital General Universitario Gregorio Mara?ón. MATERIALS AND METHODS: Between 1994 and 1998, one or more isolates of Gemella sp. were found in 128 patients. The 113 patients with isolates from nonsignificant specimens or representing intra-abdominal infections were excluded. The clinical records of the remaining 15 patients were reviewed as well as the more recent literature. RESULTS: Mean age of patients was 41 years. The underlying conditions most frequently noted were intravenous drug users (n=6; 3 positive for human immunodeficiency virus), alcoholism (n=2), cardiovascular disease (n=2), chronic lung disease (n=2), diabetes (n=1), kidney transplant (n=1). The extra-abdominal infections were skin and soft tissue abscess (n=5), empyema (n=4), brain abscess (n=2), primary bacteremia (n=1), lung abscess (n=1), septic thrombophlebitis (n=1), complicated urinary tract infection (n=1). The infection was monomicrobial in six and polymicrobial in nine cases. Surgical drainage and betalactam antibiotics were used. The outcome was favorable in almost all cases. CONCLUSIONS: Gemella sp. should be included as a cause of localized soft-tissue abscesses, empyema, and bloodstream infection. No case of infective endocarditis was found. Although it is susceptible to several antibiotics, Gemella sp. requires a careful microbiologic diagnosis and a subtle clinical interpretation.  相似文献   
77.
BACKGROUND: Tuberculosis (TB) recurrences can be due to either reactivation by the same strain (standard assumption) or reinfection by a new strain. Reinfection has mainly been studied in selected populations with a high risk of reexposure to TB. Our aim was to analyze the role of reinfection in TB recurrences in unselected populations, without the clinical/epidemiological circumstances that favor the involvement of a new different strain of Mycobacterium tuberculosis in the recurrence. METHODS: A molecular typing analysis was performed with 92 sequential isolates of M tuberculosis from 43 patients with recurrent TB, during a 12-year period. The subjects were both positive and negative for the human immunodeficiency virus, most did not adhere to anti-TB therapy, and they lived in an area with a moderate incidence of TB. Recurrence was considered as being caused by reinfection when the molecular fingerprints for the strains involved in the sequential episodes of TB were different. RESULTS: In 14 (33%) of the 43 patients, different M tuberculosis strains were involved in the first and in subsequent episodes of TB. Reinfection was found for patients who were both positive and negative for the human immunodeficiency virus, and most patients did not adhere to anti-TB therapy. Differences between the reinfection and reactivation groups were not significant (P =.77) according to the time interval between episodes. CONCLUSIONS: Reinfection plays an important role in recurrent TB in a population without the clinical/epidemiological circumstances that are usually assumed to favor it. Reinfection should, thus, be considered as a cause of TB recurrences in a wider context than before.  相似文献   
78.
79.
The optimal timing of surgery in case of synchronous presentation of colorectal cancer and liver metastases is still under debate. Staged approach, with initial colorectal resection followed by liver resection (LR), or even the reverse, liver-first approach in specific situations, is traditionally preferred. Simultaneous resections, however, represent an appealing strategy, because may have perioperative risks comparable to staged resections in appropriately selected patients, while avoiding a second surgical procedure. In patients with larger or multiple synchronous presentation of colorectal cancer and liver metastases, simultaneous major hepatectomies may determine worse perioperative outcomes, so that parenchymal-sparing LR should represent the most appropriate option whenever feasible. Mini-invasive colorectal surgery has experienced rapid spread in the last decades, while laparoscopic LR has progressed much slower, and is usually reserved for limited tumours in favourable locations. Moreover, mini-invasive parenchymal-sparing LR is more complex, especially for larger or multiple tumours in difficult locations. It remains to be established if simultaneous resections are presently feasible with mini-invasive approaches or if we need further technological advances and surgical expertise, at least for more complex procedures. This review aims to critically analyze the current status and future perspectives of simultaneous resections, and the present role of the available mini-invasive techniques.  相似文献   
80.
For many years, it has been recognized that hypertension tends to cluster with various anthropometric and metabolic abnormalities including abdominal obesity, elevated triglycerides, reduced high-density lipoprotein cholesterol, glucose intolerance, insulin resistance and hyperuricemia. This constellation of various conditions has been transformed from a pathophysiological concept to a clinical entity, which has been defined metabolic syndrome(MetS). The consequences of the MetS have been difficult to assess without commonly accepted criteria to diagnose it. For this reason, on 2009 the International Diabetes Federation, the American Heart Association and other scientific organizations proposed a unified MetS definition. The incidence of the MetS has been increasing worldwide in parallel with an increase in overweight and obesity. The epidemic proportion reached by the MetS represents a major public health challenge, because several lines of evidence showed that the MetS, even without type 2 diabetes, confers an increased risk of cardiovascular morbidity and mortality in different populations including also hypertensive patients. It is likely that the enhanced cardiovascular risk associated with MetS in patients with high blood pressure may be largely mediated through an increased prevalence of preclinical cardiovascular and renal changes, such as left ventricular hypertrophy, early carotid atherosclerosis, impaired aortic elasticity, hypertensive retinopathy and microalbuminuria. Indeed, many reports support this notion, showing that hypertensive patients with MetS exhibit, more often than those without it, these early signs of end organ damage, most of which are recognized as significant independent predictors of adverse cardiovascular outcomes.  相似文献   
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