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981.
Pyogenic hepatic abscess with biliary communication   总被引:1,自引:0,他引:1  
BACKGROUND: The aims of this study were to compare the effectiveness of percutaneous drainage between pyogenic hepatic abscesses with and those without biliary communication and to evaluate the role of endoscopic biliary stent placement in the treatment of communicating abscesses. METHODS: Sixty-one patients with hepatic abscesses underwent percutaneous drainage. For communicating abscesses refractory to drainage alone, endoscopic biliary stenting was performed. RESULTS: After drainage, all patients showed improvement in their clinical condition and reduction in abscess size. Drainage alone completely cured abscesses in none of 10 patients with biliary communication and obstruction, in 3 of 10 with communication but without obstruction, and in 37 of 41 without communication. Endoscopic stenting was completely effective in all 7 patients with persistent discharge from a communicating abscess without biliary obstruction. CONCLUSIONS: Percutaneous drainage is less effective for communicating abscesses without biliary obstruction than for noncommunicating abscesses. Endoscopic biliary stenting is recommended, if drainage does not achieve a cure.  相似文献   
982.
BACKGROUND: A standardized neck management strategy for oral cancer patients without clinical nodal metastases remains to be established. Consequently, a decision and sensitivity analysis of two neck management protocols, involving either prophylactic neck dissection or careful observation, was conducted using the Oral Cancer Registry of Kyushu, Japan. METHODS: We calculated probabilities of subclinical nodal metastases and 5-year survival using the registry data. A two-way sensitive analysis was conducted using the probabilities and parameters of the complete nodal metastasis resection rate (x) and a utility rating that describes the health state induced by dissection (y) compared with the neck condition in a careful-observation group. RESULTS: We solved the threshold curve for y and x for the expected utility between the two groups. The results showed that prophylactic neck dissection must guarantee a complete resection of subclinical nodal metastases with no disadvantage to health state to be evaluated as equally satisfactory as careful observation. CONCLUSIONS: Careful observation involving standardized systematic preoperative and postoperative screening of the neck seems preferable to prophylactic neck dissection for oral cancer patients without subclinical nodal metastases.  相似文献   
983.
A new ginsenoside and 22 known compounds were isolated from the roots of Panax notoginseng (Araliaceae). The structure of the new compound was elucidated from 2D-NMR and other spectral evidence.  相似文献   
984.
Purpose: To examine changes in the reference segment luminal diameter after coronary angioplasty. Methods: Sixty-one patients with stable angina pectoris or old myocardial infarction were examined. Coronary angiograms were recorded before coronary angioplasty (pre-angioplasty) and immediately after (post-angioplasty), as well as 3 months after. Artery diameters were measured on cine-film using quantitative coronary angiographic analysis. Results: The diameters of the proximal segment not involved in the balloon inflation and segments in the other artery did not change significantly after angioplasty, but the reference segment diameter significantly decreased (4.7%). More than 10% luminal reduction was observed in seven patients (11%) and more than 5% reduction was observed in 25 patients (41%). More than 5% underestimation of the stenosis was observed in 22 patients (36%) when the post-angioplasty reference diameter was used as the reference diameter, compared with when the pre-angioplasty measurement was used and more than 10% underestimation was observed in five patients (8%). Conclusion: This study indicated that evaluation by percent diameter stenosis, with the reference diameter from immediately after angioplasty, overestimates the dilative effects of coronary angioplasty, and that it is thus better to evaluate the efficacy of angioplasty using the absolute diameter in addition to percent luminal stenosis.  相似文献   
985.
OBJECTIVE: To evaluate the usefulness of sequential T2-weighted spin-echo type multishot echo-planar (T2-EP) imaging with gadopentetate dimeglumine for the detection of hypovascular metastatic liver tumors. MATERIAL AND METHODS: Fifteen consecutive patients with 56 proven hypovascular metastatic liver tumors were included in the study. Three observers blindly and independently read the whole-liver images obtained with T2-weighted spin-echo, T2-weighted single-shot fast spin-echo, T1-weighted fast multiplanar spoiled GRASS and T2-EP images obtained before and 25, 60, 90 and 120 s after injection of 0.2 mmol/kg b.w. of gadopentetate dimeglumine. The diagnostic accuracy was estimated by calculating the area under the observer-specific binomial receiver operating characteristics curves (Az). RESULTS: T2-EP images obtained 60 s after contrast injection showed significantly higher contrast-to-noise (C/N) ratios than the other imaging techniques. A combination of all phases of the T2-EP images produced the highest sensitivity and specificity. In terms of the Az value, the diagnostic accuracy for tumor detection achieved with a combination of all phases of the T2-EP images was significantly higher than that with T1-SPGR and T2-SSFSE images (p<0.01). The Az values of the T2-EP images (Az=0.975) were higher than those of T2-CSE images (Az=0.948), but the difference was not significant. CONCLUSION: Our preliminary study revealed that sequential imaging with enhanced T2-EP images was useful for the detection of hypovascular metastatic liver tumors because of its superior C/N ratio and sensitivity.  相似文献   
986.
Positron emission tomography (PET) with [18F]2-fluoro-2-deoxy-D-glucose (FDG) may show negative results for bronchioloalveolar lung carcinoma. We investigated the correlation of Glut-1 glucose transporter expression with [18F]FDG uptake in non-small cell lung cancer. Thirty-two patients with 34 non-small cell lung cancers (7 bronchioloalveolar carcinomas, 23 non-bronchioloalveolar adenocarcinomas, 3 squamous cell carcinomas, and 1 adenosquamous cell carcinoma) were studied. Final diagnoses were established by histology (via thoracotomy) in all patients. [18F]FDG PET was performed 40 min after i.v. injection of 185 MBq [18F]FDG. For semi-quantitative analysis of [18F]FDG uptake, standardized uptake values (SUVs) were calculated. Glut-1 expression was studied in terms of the immunohistochemistry of paraffin sections using anti-Glut-1 antibody to determine the intensity (0-3) of Glut-1 immunoreactivity and percentage of the Glut-1-positive area. Of seven bronchioloalveolar carcinomas, six (85.7%) were negative for the expression of Glut-1, while only one (4.3%) of 23 non-bronchioloalveolar adenocarcinomas was negative (P < 0.0001). The percentages of Glut-1-positive area, as well as the SUVs, were significantly lower in bronchioloalveolar carcinomas (n = 7) (2.86% +/- 7.56% and 1.25 +/- 0.75, respectively) than in non-bronchioloalveolar adenocarcinomas (n = 23) (54.83% +/- 25.64%, P < 0.0001, and 3.94 +/- 1.93, P = 0.001, respectively). The degree of cell differentiation correlated with the percentage of Glut-1-positive area and SUVs in adenocarcinoma of the lung. Correlations between SUVs and the intensity of Glut-1 immunoreactivity were also significant (intensities 0 and 1, n = 11, SUV 1.47 +/- 0.63; intensities 2 and 3, n=23, SUV 4.78 +/- 2.13; P < 0.0001). The percentage of Glut-1-positive area correlated significantly with SUVs (n = 34, r = 0.658, P < 0.01). Overexpression of Glut-1 correlated with high [18F]FDG uptake. These findings suggest that Glut-1 expression is related to [18F]FDG uptake in non-small cell lung cancer. Glut-1 expression, as well as [18F]FDG uptake, correlated with the degree of cell differentiation in adenocarcinomas, and both Glut-1 expression and [18F]FDG uptake were significantly lower in bronchioloalveolar carcinomas than in non-bronchioloalveolar carcinomas.  相似文献   
987.
988.
Various carcinogenic metabolites, including catechol estrogens, play a role in malignant transformation. An enzyme that is capable of neutralizing the genotoxic effects of these compounds is catechol-O-methyltransferase (COMT). A variant form of this enzyme has been shown to reduce its activity by up to 4-fold; thus, we hypothesize that single nucleotide polymorphisms of the COMT gene can be a risk factor for benign prostatic hyperplasia (BPH) and prostate cancer. To test this hypothesis, the genetic distribution of three different COMT polymorphisms at codon 62 (C-->T), codon 72 (G-->T), and codon 158 (G-->A) were analyzed in 131 normal healthy subjects, 134 BPH, and 178 sporadic prostate cancer samples from a Japanese population. Results of these experiments show that the variant genotype at codon 62 (P = 0.060) and codon 158 (P = 0.047) are risk factors for prostate cancer but not BPH when compared with normal controls. Odds ratio (OR) and 95% confidence interval (95% CI) for cancer were 3.24 and 1.38 to 7.61, respectively, for codon 62 T/T genotype when compared with wild type. At codon 158, the A/A variant for cancer had an OR of 3.00 with a 95% CI of 1.38 to 6.54 compared with wild type. Codons 62 and 158 were in linkage disequilibrium (LD), and when compared with the C-G haplotype, other types (C-A, T-G, T-A) were observed to be associated with prostate cancer (P = 0.040) but not BPH. Codon 72 on the other hand, was not in LD with either codon 62 or 158. The homozygous variant on codon 72 was rare in this Japanese population, and the heterozygous G/T at this codon was not associated with either prostate cancer or BPH. When evaluating the risk of COMT polymorphisms with stage or grade of cancer, no associations were observed for any of the genotypes with the exception of a tendency (P = 0.096) for the variant A allele on codon 158 to be correlated with higher stages (> or = T3) of cancer. This is the first report that shows the polymorphisms of COMT to be associated with sporadic prostatic carcinogenesis. These results are important in understanding the role of COMT polymorphisms in the pathogenesis of prostate cancer.  相似文献   
989.
To clarify the mechanisms of action of carbamazepine (CBZ), we investigated the effects of CBZ on acetylcholine (ACh) release and metabolism in rat striatum and hippocampus. Acute administration of effective dose of CBZ (25 mg/kg) increased both striatal and hippocampal extracellular levels of ACh, whereas a supraeffective dose of CBZ (50 mg/kg) did not affect the levels and a toxic dose of CBZ (100 mg/kg) decreased the extracellular ACh levels in both brain regions. Both acute and chronic administrations of CBZ (25 and 50 mg/kg, mg/kg per day) increased intracellular ACh levels in striatum and hippocampus. The striatal intracellular ACh levels were decreased by both acute and chronic administrations of CBZ (100 mg/kg, mg/kg per day), whereas the hippocampal intracellular ACh levels were not affected. The effective CBZ concentration did not affect cholinesterase activity, whereas supraeffective CBZ concentration reduced it weakly. Effective dose of CBZ enhanced ACh release and synthesis; however, supraeffective doses of CBZ reduced ACh release and synthesis without enhancement of ACh degradation, indicating that CBZ has biphasic effects on ACh release and synthesis. Thus, the present findings, the slight stimulation of ACh function by effective dose of CBZ, are involved, at least partially, in the antiepileptic and mood stabilizing mechanisms of action of CBZ.  相似文献   
990.
(Received for publication on Dec. 16, 1998; accepted on Nov. 11, 1999)  相似文献   
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