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1.
During the period 1966-1985, 66 patients were submitted for curative treatment of a carcinoma of the base of the tongue in the Netherlands Cancer Institute. Treatment consisted of radiotherapy (59 patients), surgery and post-operative radiotherapy (4 patients) and surgery alone (3 patients). Patients were staged according to the UICC (1982) and UICC (1987)/AJCC (1988) criteria. Regrouping by the latter system caused enlargement of the N2-group and of stage IV. The crude 5-year survival was 22%, the 5-year tumour control was 36% and the locoregional control was 47%. The most important prognostic factors for the tumour-free interval are the T-category (P = 0.01) and stage grouping (UICC 1982) (P = 0.022). The same factors predict the locoregional control (P = 0.005 and 0.02 respectively). Crude survival is lower in smokers, and in patients in poor general condition (P = 0.04 and 0.007 respectively).  相似文献   
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The OPA1 gene, encoding a dynamin-related GTPase that plays a role in mitochondrial biogenesis, is implicated in most cases of autosomal dominant optic atrophy (ADOA). Sixty-nine pathogenic OPA1 mutations have been reported so far. Most of these are truncating mutations located in the GTPase domain coding region (exons 8-16) and at the 3'-end (exons 27-28). We screened 44 patients with typical ADOA using PCR-sequencing. We also tested 20 sporadic cases of bilateral optic atrophy compatible with ADOA. Of the 18 OPA1 mutations found, 14 have never been previously reported. The novel mutations include one nonsense mutation, 3 missense mutations, 6 deletions, one insertion and 3 exon-skipping mutations. Two of these are de novo mutations, which were found in 2 patients with sporadic optic atrophy. The recurrent c.2708_2711delTTAG mutation was found in 2 patients with a severe congenital presentation of the disease. These results suggest that screening for OPA1 gene mutations may be useful for patients with optic atrophy who have no affected relatives, or when the presentation of the disease is atypical as in the case of early onset optic atrophy.  相似文献   
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Byssinosis in carpet weavers exposed to wool contaminated with endotoxin   总被引:1,自引:0,他引:1  
All the 303 full time day workers in a carpet weaving factory were submitted to a physical examination, chest radiography, and vitalograph test, and answered a respiratory questionnaire. Fifty four healthy non-exposed subjects served as controls. Dust concentrations and concentrations of bacterial endotoxin were measured. Of the 303 workers, 259 (85.5%) had airway symptoms and 62 (20.5%) had maximum mid-expiratory flow (MMF) values of less than 60% compared with 9.2% of the controls. The symptoms in 68 workers (22%) were compatible with byssinosis and 36 of these workers underwent vitalography before starting work and after four hours work on Mondays when significant reductions of their FEV1 and MMF were found. Twenty one of these 36 workers were tested on Tuesday and no differences in these measurements were found between measurements before work started and four hours later. The airborne dust concentrations in the factory were high and bacterial endotoxin was found. These findings suggest that a large number of workers in this carpet weaving factory suffer from a disease indistinguishable from byssinosis even though wool is used almost exclusively, the only cotton being the warp. The finding of endotoxin together with the absence of cotton confirms the theory that "byssinosis" is due to bacterial endotoxin rather than to cotton per se.  相似文献   
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Background/AimsTo investigate the presence of seronegative celiac disease in patients with isolated refractory dyspepsia and gastroesophageal reflux disease (GERD)-related complaints.MethodsThis was a single-center, prospective study performed at a tertiary care referral hospital. Among 968 consecutive patients, 129 seronegative patients with tissue damage consistent with Marsh IIIa classification or above were included. The patients were divided into two groups dyspepsia (n=78) and GERD (n=51). Biopsies were taken from the duodenum regardless of endoscopic appearance, and patients with Marsh IIIa or above damage were advised to consume a gluten-free diet. The Glasgow Dyspepsia Severity (GDS) score, Reflux Symptom Index (RSI), and Biagi score were calculated at baseline and every 3 months. Control endoscopy was performed every 6 months during follow-up.ResultsThe median follow-up time was 19.9 months (range, 6 to 24 months) in the dyspepsia group and 19.2 months (range, 6 to 24 months) in the GERD group. All the patients were positive for the HLA-DQ2 and DQ8 haplotypes. The differences between the mean GDS scores (14.3±2.1 vs 1.1±0.2, respectively, p<0.05), RSI scores (6.3±0.8 vs 0.7±0.1, respectively, p<0.05), and Biagi scores (3.1±0.4 vs 0.7±0.3 in the dyspepsia group and 2.5±0.4 vs 0.5±0.2 in GERD group) before and after implementation of the gluten-free diet were statistically significant. The decreases in the scores were consistent with improvements in the histological findings. There was no significant correlation between endoscopic appearance and histological examination results (p=0.487).ConclusionsSeronegative celiac disease may be considered in this group of patients. Even if a patient is seronegative and has normal endoscopic findings, duodenal biopsy should be considered.  相似文献   
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OBJECTIVE: It has been advocated that a reduced injection volume with highly concentrated (1 M) contrast material can produce a sharper bolus peak and an increased intravascular first-pass gadolinium concentration when compared with the use of a lower concentration (0.5 M). A higher concentration would also cause a reduction in dose. The purpose of our study was to test the use of a low dose (0.05 mmol/kg) of gadobutrol in magnetic resonance renography and angiography and compare the findings with a dose of 0.1 mmol/kg. MATERIALS AND METHODS: One-hundred-thirty-four patients referred for magnetic resonance angiography for suspected renovascular disease participated in the study. Contrast enhanced MR renography and angiography were performed after administration of a bolus of 0.1 mmol/kg or 0.05 mmol/kg gadobutrol in randomized patients. The relative signal intensity-time curves of the aorta, peripheral cortex and parenchyma, were obtained. Two radiologists evaluated the angiographic images and evaluated the quality of angiography. RESULTS: The signal intensity with a low dose of gadobutrol was significantly lower in early phases, in the peripheral cortex (for 36, 54, 72 and 90 seconds), the parenchyma (for 36, 54, 72 seconds) and the aorta (for 18, 36, 54, 72 seconds). The decreases in the early phase obtained with a low dose of gadobutrol caused blunter time intensity curves. The difference in the quality scores of the readers for the angiographic images for the use of the two different doses was not statistically significant (p > 0.05). CONCLUSION: A lower dose of gadobutrol can be used for MR renal angiography, but for MR renography the normal dose should be used.  相似文献   
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Study Type – Diagnostic (exploratory cohort)
Level of Evidence 2b What’s known on the subject? and What does the study add? Currently, systematic prostate biopsies are obtained with minimal information about their actual location. This study demonstrates that a electromagnetically tracked ultrasound probe can be used to guide biopsies into specific areas of the prostate. By registering the ultrasound to an MRI scan of the prostate, obtained prior to biopsy, it is possible to accurately map the location of biopsies. Thus, if a patient requires a repeat biopsy, or there is a question about whether a specific area of the prostate was sampled, this system can be used to more accurately guide biopsies in the future. OBJECTIVE To develop a system that documents the location of transrectal ultrasonography (TRUS)‐guided prostate biopsies by fusing them to MRI scans obtained prior to biopsy, as the actual location of prostate biopsies is rarely known. PATIENTS AND METHODS Fifty patients (median age 61) with a median prostate‐specific antigen (PSA) of 5.8 ng/ml underwent 3T endorectal coil MRI prior to biopsy. 3D TRUS images were obtained just prior to standard TRUS‐guided 12‐core sextant biopsies wherein an electromagnetic positioning device was attached to the needle guide and TRUS probe in order to track the position of each needle pass. The 3D‐TRUS image documenting the location of each biopsy was fused electronically to the T2‐weighted MRI. Each biopsy needle track was marked on the TRUS images and these were then transposed onto the MRI. Each biopsy site was classified pathologically as positive or negative for cancer and the Gleason score was determined. RESULTS The location of all (n= 605) needle biopsy tracks was successfully documented on the T2‐weighted (T2W) MRI. Among 50 patients, 20 had 56 positive cores. At the sites of biopsy, T2W signal was considered ‘positive’ for cancer (i.e. low in signal intensity) in 34 of 56 sites. CONCLUSION It is feasible to document the location of TRUS‐guided prostate biopsies on pre‐procedure MRI by fusing the pre‐procedure TRUS to an endorectal coil MRI using electromagnetic needle tracking. This procedure may be useful in documenting the location of prior biopsies, improving quality control and thereby avoiding under‐sampling of the prostate as well as directing subsequent biopsies to regions of the prostate not previously sampled.  相似文献   
9.

Background/Purpose

The aim of this study was to investigate the effect of peritonitis on spontaneous contractions of distal and proximal colon smooth muscle isolated from rats.

Methods

Peritonitis was induced by cecal ligation and puncture in 8 rats. Another group of 8 rats underwent a sham operation and acted as controls. Twenty-four hours after the operation, the rats were killed; and their distal and proximal colon smooth muscle was excised and placed in circular muscle direction in a 10-mL organ bath. Changes in the amplitude and frequency of contractions were analyzed before and after the addition of antagonists.

Results

Peritonitis induced the increase in the amplitude and frequency of spontaneous contractions. In both distal and proximal colon of the control group, the amplitude of spontaneous contractions was elevated by NG-nitro-l-arginine and tetradotoxin; but the frequency of spontaneous contractions was significantly elevated only in the presence of NG-nitro-l-arginine. In both distal and proximal colon of the peritonitis group, the enhanced amplitude and frequency were significantly decreased and returned to control values in the presence of celecoxib.

Conclusions

Peritonitis induces the increase in the amplitude and frequency of spontaneous contractions of distal and proximal colon, which can be attributed to a loss of inhibitor nitrergic and other neural control or rise of cyclooxygenase-2 levels.  相似文献   
10.
PURPOSE: The purpose of this study was to evaluate the treatment of patients with Mason type III radial head fracture with and without elbow dislocation by open reduction with internal fixation, collateral ligament repair, and early mobilization. An additional purpose was to investigate whether there is any effect of elbow dislocation on the severity and functional outcome. METHODS: Twenty-five patients were treated with open reduction with internal fixation using low-profile miniplate and screws for comminuted fracture of the radial head. Eighteen fractures were Mason type III, and 7 fractures were Mason type III with elbow dislocation. There were 5 women and 20 men with a mean age of 34 years. The mean follow-up time was 27 months. Patients were reviewed for functional ability, physical examination, and radiographic assessment. RESULTS: The mean functional index in Mason type III fracture and Mason type III fracture with elbow dislocation was 87 for both groups. The mean range of motion at the elbow joint was calculated as 5 degrees extension to 136 degrees flexion for Mason type III and 7 degrees extension to 133 degrees flexion for Mason type III with elbow dislocation. The mean pronation and supination for all patients were 74 degrees and 67 degrees , respectively. CONCLUSIONS: Selected Mason III radial head fractures and fracture dislocations could be stabilized satisfactorily with internal fixation. Meticulous surgical technique, combined with rigid internal fixation, can allow early motion of the forearm and elbow after fixation of Mason type III radial head fractures with and without elbow dislocation and ligamentous injury. We believe there is still a role for prosthetic replacement in comminuted Mason III radial head fractures that cannot reliably be treated with open reduction and internal fixation. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.  相似文献   
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