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991.
Cardiac failure is among the most significant conditions associated with acute coronary syndrome. In ischemic heart disease, serious hemodynamic problems are reported in patients with left ventricular dysfunction during the acute phase despite mechanical revascularization. Several positive inotropic agents in addition to intra-aortic balloon pump (IABP) are required to support patients with impaired left ventricular pump function during this phase. Intravenous inotropic agents, beta-mimetics, and phosphodiesterase inhibitors lead to increases in the incidence of arrhythmia and myocardial O2 consumption owing to their effect of increasing intracellular calcium amount, although they produce rapid hemodynamic improvements in cardiac failure. This causes severe problems particularly in cardiac failure of ischemic origin. Recently, levosimendan, a calcium-sensitizing agent with cardioprotective properties, is being used alone or in combination with IABP in cases with severe left ventricular systolic dysfunction during mechanical revascularization procedures (percutaneous coronary interventions, coronary bypass surgery). This review includes studies with levosimendan in cases not recovering due to myocardial stunning in the acute phase despite mechanical approaches applied.  相似文献   
992.
Purpose  We consider quality of surgery throughout the learning curve and attempt to determine the learning curve for competency in performing laparoscopic colorectal surgery. Methods  The study included 1,014 patients who underwent laparoscopic colorectal resection between June 1996 and December 2007. We categorized patients into nine periods according to number of cases performed. Results  Operative time continuously decreased for right hemicolectomy (216 versus 150 min) and anterior resection (214.8 versus 147.7 min), whereas for low anterior resection it did not change over many periods and then significantly decreased after the ninth period (221.3 versus 176.4 min). The proportion of patients who had undergone previous abdominal surgery increased after the second period. Anastomotic leakage rate was 6–9% for the first 200 cases, and then decreased to less than 2%. More than 10% of operations were converted to open surgery during the first period, after which this rate significantly decreased to 2%. Number of harvested lymph nodes stabilized to 35–40 for right hemicolectomy after 200 cases, whereas for anterior and low anterior resection it was consistently 15–20 after the initial 20 cases. Overall, disease recurrence rate was 16–25%. For rectal cancer, local recurrence rate was highest (12%) in the fourth period and decreased thereafter to about 3%. Conclusion  Postoperative complications and local recurrence rate increased even after accumulation of experience because of expansion of indications for laparoscopic procedures.  相似文献   
993.

Background/Purpose

Fetal tracheal occlusion (TO) was developed in an attempt to enhance prenatal lung growth and improve survival in fetuses with severe congenital diaphragmatic hernia (CDH). We conducted a randomized, controlled clinical trial in 24 fetuses with severe left CDH (liver herniated into the thorax and low lung-to-head ratio) to compare survival after endoscopic fetal TO vs standard perinatal care (control) and prospectively followed up the 16 survivors (9 control, 7 TO) to compare neurodevelopmental, respiratory, surgical, growth, and nutritional outcomes.

Methods

At 1 and 2 years old, subjects underwent evaluation consisting of medical and neurological history and physical, developmental testing, nutritional assessment, oxygen saturation and pulmonary function testing, chest radiograph, and echocardiogram. Growth and developmental measures were corrected for prematurity. Data were analyzed by Mann-Whitney rank sum test, Fisher's Exact test, and logistic and linear regression.

Results

Infants with TO were significantly more premature at birth (control vs TO, 37.4 ± 1.0 vs 31.1 ± 1.7 weeks; P < .01). Growth failure (z score for weight <2 SDs below mean) was severe in both groups at 1 year of age (control vs TO, 56% vs 86%; P = .31). There was considerable catch-up growth by age 2 years (growth failure: control vs TO, 22% vs 33%; P = .19). There were no differences in other growth parameters. There were also no differences in neurodevelopmental outcome at 1 and 2 years. Supplemental oxygen at hospital discharge was a significant predictor of worse neurodevelopmental outcome at 1 and 2 years old (P = .05 and P = .02, respectively). Hearing loss requiring amplification has been diagnosed in 44% of the group (control vs TO, 44% vs 43%; P = 1.0).

Conclusions

In this group of infants with severe CDH, there were no differences in outcome at 2 years old despite significant prematurity in the TO group. Oxygen supplementation at hospital discharge identified the most vulnerable group with respect to neurodevelopmental outcome, but all infants had significant growth failure, and hearing impairment is a substantial problem in this population. Severe CDH carries significant risk of chronic morbidity.  相似文献   
994.

Purpose:

This blinded study evaluates the N2O concentration variations in an ambulatory surgery centre using a small, simple on-line trace gas concentration monitor (GasFinder™ [Medair AB, Delsbo, Sweden]).

Scope:

Thirty-seven day surgical sessions using standardised anaesthesia with propofol/fentanyl induction and sevoflurane/N2O with larynx mask. Five of 37 time-weighted averages (TWA) were greater than 25 ppm but less than 100. Peak registered concentrations reached 2000 ppm. Eleven sessions showed peak values higher than 100 ppm (range 13-1693).

Conclusions:

This simple, on-line N2O monitor is a useful tool for detecting deviations from strict gas hygiene.  相似文献   
995.
Robotic systems are increasingly being incorporated into general laparoscopic and thoracoscopic surgery to perform procedures such as cholecystectomy and prostatectomy. Robotic assisted surgery allows the surgeon to conduct minimally invasive surgery with increased accuracy and with potential benefits for patients. However, current robotic systems have their limitations. These include the narrow operative field of view, which can make instrument manipulation difficult. Current robotic applications are also tailored to specific surgical procedures. For these reasons, there is an increasing demand on surgeons to master the skills of instrument manipulation and their surgical application within a controlled environment. This study describes the development of a surgical simulator for training and mastering procedures performed with the da Vinci surgical system. The development of a tele-surgery simulator and the construction of a training center are also described, which will enable surgeons to simulate surgery from or in remote places, to collaborate over long distances, and for off-site expert assistance.  相似文献   
996.
997.
Recently, some useful robotic surgical systems have been developed and applied in many surgical situations. Systems such as the da Vinci surgical system of Intuitive Surgical Inc., which facilitates minimally invasive surgery with increased dexterity, are commercially available. Preoperative simulation and planning of surgical robot setups should accompany advanced robotic surgery if their advantages are to be further pursued. Feedback from the planning system will play an essential role in computer-aided robotic surgery in addition to preoperative detailed geometric information from patient CT/MRI images. Surgical robot setup simulation systems for appropriate trocar site placement have been developed especially for abdominal surgery. The motion of the surgical robot can be simulated and rehearsed with kinematic constraints at the trocar site, and the inverse-kinematics of the robot. Results from simulation using clinical patient data verify the effectiveness of the proposed system.  相似文献   
998.
BACKGROUND: Previous studies have shown conflicting results regarding the effect of autotransfusion of mediastinal shed blood after coronary artery bypass grafting (CABG) on the serum levels of myocardial band (MB) isoenzymes of creatine kinase (CK-MB) and cardiac troponins. The effect of autotransfusion on serum levels of human heart fatty acid binding protein (H-FABP), another marker of myocardial necrosis, has not been studied. The aim of the present study was to investigate the effects of autotransfusion of mediastinal shed blood on the serum levels of CK-MB, cardiac troponin T (cTnT), and H-FABP after uncomplicated primary CABG. METHODS: Fifty patients were randomized to post-operative autotransfusion of mediastinal shed blood or no autotransfusion. Blood samples for the analysis of the biochemical markers of myocardial damage were drawn pre-operatively and 1, 4, 12, 24, 48, and 72 h after the termination of cardiopulmonary bypass. Samples from the mediastinal shed blood were collected after 1 and 4 h. RESULTS: The levels of the biochemical markers of myocardial injury were all markedly elevated in mediastinal shed blood. Autotransfusion did not significantly affect the serum levels of cTnT or H-FABP. However, during the early post-operative hours, there was a trend towards a higher level of cTnT and H-FABP in the autotransfusion group. During the first 24 h after surgery, the autotransfusion group had a significantly higher serum level of CK-MB. CONCLUSION: Post-operative autotransfusion of mediastinal shed blood may contribute to elevated serum levels of biochemical markers of myocardial injury.  相似文献   
999.
1000.
OBJECTIVE: To report an unusual and asymptomatic cause of cord compression treated surgically with good clinical outcome. METHODS AND MATERIAL: We report a case of extradural arachnoid cyst in the thoracic region and review the literature on the clinical, neuroradiologic and therapeutic features. RESULTS: A 17-year-old man, with unremarkable past medical history was referred to our institution of Neurosurgery, CHU Mohammed-VI, Marrakech, with progressive spastic paraparesis. Magnetic resonance imaging (MRI) showed a posterior extradural cystic lesion in the thoracic region from T6-T7 thoracic vertebra. The cyst was completely removed by posterior approach. An arachnoid cyst was confirmed at the histological study. Neurological symptoms improved after surgery. CONCLUSION: Given its infrequency, the diagnosis of arachnoid cyst should be suspected when a cystic lesion causes cord compression. Surgery is the treatment of choice, providing good clinical outcome.  相似文献   
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