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11.
12.
Christian Casali Alessandro Stefani Pamela Natali Giulio Rossi Uliano Morandi 《European journal of cardio-thoracic surgery》2005,28(1):33-38
OBJECTIVE: Patients with non-small cell lung cancer (NSCLC) with metastases to ipsilateral mediastinal lymph nodes (N2) are an heterogeneous group of patients as regard to prognosis and treatment. Indication and timing of surgery remain controversial. The present study investigates the prognostic factors, in order to identify homogenous subgroups of patients. METHODS: Histologically proven N2-NSCLC patients, who underwent a complete surgical resection were retrospectively reviewed. Clinical and pathological features were reported and analyzed, and survival study was performed. RESULTS: One hundred eighty-three patients were analyzed. Overall 1.3 and 5 years survival rates were, respectively, 70, 35 and 20%, with a median survival time of 24 months. Univariate analysis showed a significant better prognosis for: incidental N2 respect to clinical N2 (5-years 35.4 vs 17.4%); single level lymph node involvement respect to multiple levels (5-years 23.8 vs 14.7%); metastases to superior mediastinal or aortic nodes respect to lower mediastinal nodes (5-years 32 and 24.3 vs 16.3%); right upper lobe tumors with superior mediastinal nodes and left upper lobe tumors with aortic nodes respect to lower lobes tumors with lower mediastinal nodes (5-years 31.8 and 26.9 vs 15.7%). Skip metastases had not a significant survival advantage respect to continuous lymphatic spread. N2 clinical status, the number of levels involved and the two specific patterns of lymphatic spread resulted significant prognostic factors at multivariate analysis. CONCLUSIONS: Clinical N2 status, number of lymph nodes levels involved and specific patterns of lymphatic spread identify homogenous subgroups of patients that can be proposed for different therapeutic strategies. 相似文献
13.
Flavio Masi Benedetta Leggio Giulio Nanni Simona Scheggi M Graziella De Montis Alessandro Tagliamonte Silvia Grappi Carla Gambarana 《Neuropsychopharmacology》2003,28(4):683-693
Long-term acetyl-L-carnitine (ALCAR) administration prevents the development of escape deficit produced by acute exposure to unavoidable stress. However, it does not revert the escape deficit sustained by chronic stress exposure. Rats exposed to chronic stress show a low dopamine (DA) output in the nucleus accumbens shell (NAcS) and do not acquire an appetitive behavior sustained by the earning of vanilla sugar (VS) made contingent on the choice of one of the two divergent arms of a Y-maze (VS-sustained appetitive behavior, VAB), while control rats consistently do. The present study shows that ALCAR treatment in rats exposed to a 7-day stress protocol prevented a decrease in DA output in the NAcS and medial prefrontal cortex (mPFC) of rats, and that it strengthened the DA response to VS consummation in the same two areas. Moreover, rats treated with long-term ALCAR or exposed to chronic stress while treated with ALCAR acquired VAB as efficiently as control rats. Moreover, VAB acquisition in stressed rats treated with ALCAR coincided with the reversal of the deficits in escape and in dopaminergic transmission in the NAcS. Thus, repeated ALCAR treatment preserved the DA response to VS in chronically stressed rats and this effect appeared to be predictive of the rat's competence to acquire VAB. 相似文献
14.
Glycosaminoglycan Supplementation Promotes Nerve Regeneration and Muscle Reinnervation 总被引:1,自引:0,他引:1
A. Gorio E. Lesma L. Vergani A. M. Di Giulio 《The European journal of neuroscience》1997,9(8):1748-1753
This study shows that treatment of rats with exogenous glycosaminoglycans stimulates peripheral nerve regeneration, increases the abundance of mRNAs for myelin proteins and promotes muscle reinnervation. After the sciatic nerve had been crushed the number of regenerating axons in the distal stump was markedly and highly significantly increased by glycosaminoglycan treatment throughout the experimental period. The increased number of axons was correlated with increased axon and fibre (axon + myelin) diameter. The abundance of mRNAs for Po protein and myelin basic protein of regenerating nerves was also affected by treatment with glycosaminoglycans. The increase in mRNA was also observed in the contralateral unlesioned nerve. Such a phenomenon did not occur in saline-treated rats. Glycosaminoglycan treatment markedly increased the number of muscle fibres reinnervated and accelerated the restoration of muscle twitch tension elicited by nerve stimulation. The effect was particularly evident during the early stages (16 and 21 days after nerve crush) of muscle reinnervation. 相似文献
15.
Giulio Jori 《Lasers in medical science》1990,5(2):115-120
The scope and potential of the photodynamic therapy of tumors can be enhanced through an adequate control of the factors which improve the selectivity of tumour targeting by the systemically injected photosensitizer and increase the efficiency of photosensitized tumour damage. Promising results are obtained by using hydrophobic photosensitizers which can be specifically transported and released to the tumour by serum lipoproteins, especially low-density lipoproteins. The photosensitizer molecule should possess those structural features which induce a high probability of photoactivation by 700–800 nm light, as well as a high yield of long-lived triplet state. The use of liposome-delivered Zn-phthalocyanine as a second generation phototherapeutic agent for tumours is proposed. 相似文献
16.
Effect of prone positioning on the survival of patients with acute respiratory failure 总被引:40,自引:0,他引:40
Gattinoni L Tognoni G Pesenti A Taccone P Mascheroni D Labarta V Malacrida R Di Giulio P Fumagalli R Pelosi P Brazzi L Latini R;Prone-Supine Study Group 《The New England journal of medicine》2001,345(8):568-573
BACKGROUND: Although placing patients with acute respiratory failure in a prone (face down) position improves their oxygenation 60 to 70 percent of the time, the effect on survival is not known. METHODS: In a multicenter, randomized trial, we compared conventional treatment (in the supine position) of patients with acute lung injury or the acute respiratory distress syndrome with a predefined strategy of placing patients in a prone position for six or more hours daily for 10 days. We enrolled 304 patients, 152 in each group. RESULTS: The mortality rate was 23.0 percent during the 10-day study period, 49.3 percent at the time of discharge from the intensive care unit, and 60.5 percent at 6 months. The relative risk of death in the prone group as compared with the supine group was 0.84 at the end of the study period (95 percent confidence interval, 0.56 to 1.27), 1.05 at the time of discharge from the intensive care unit (95 percent confidence interval, 0.84 to 1.32), and 1.06 at six months (95 percent confidence interval, 0.88 to 1.28). During the study period the mean (+/-SD) increase in the ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen, measured each morning while patients were supine, was greater in the prone than the supine group (63.0+/-66.8 vs. 44.6+/-68.2, P=0.02). The incidence of complications related to positioning (such as pressure sores and accidental extubation) was similar in the two groups. CONCLUSIONS: Although placing patients with acute respiratory failure in a prone position improves their oxygenation, it does not improve survival. 相似文献
17.
Biasco Guido Paganelli Gian Maria Psilogenis Mary Nazzari Marco Di Febo Giulio Siringo Sebastiano 《Inflammation research》1992,36(1):C88-C89
The effect on gastric epithelial cell proliferation of small doses of aspirin was evaluated in 9 healthy volunteers, with or without administration of sulglycotide, a sulfated glycopeptide with cytoprotective properties. Cell kinetics study was performed by incubation of gastric biopsies with bromodeoxyuridine (BrdU) and immunohistochemistry. A decrease of BrdU-labeling index and a shortening of the height of gastric columns were observed after treatment with aspirin and placebo. No variations were observed after treatment with aspirin and sulglycotide. A decrease of the epithelial cell renewal could be one of the damaging effects of aspirin on the gastric mucosa. The treatment with sulglycotide seems to be effective to prevent this alteration. 相似文献
18.
Cimetidine and ranitidine were tested for their effect on gastric emptying in the rat. At low doses, cimetidine was inactive, whereas it significantly delayed emptying rate when administered at higher doses. Ranitidine always accelerated gastric emptying. At variance with rats, ranitidine delayed human gastric emptying whereas cimetidine was completely inactive. All these data are consistent with the idea that these effects of H2-antagonists are independent of H2-receptor blockade. 相似文献
19.
Nitz D Tononi G 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,146(2):265-270
Simultaneous recordings of multiple single unit activity in both cerebral and cerebellar cortex, cortical EEG, and both nuchal and vibrissal EMG were obtained in nine unrestrained rats. Putative Purkinje cells of the deep vermal cerebellar cortex exhibited rhythmic discharge of simple spikes with extremely low variability in interspike intervals for several hours. The highly rhythmic nature of spike discharge was remarkably stable across all states of sleep (both slow-wave and rapid eye movement sleep) and wake including quiet waking, grooming, eating, running in a familiar environment, and exploring a novel environment. The frequencies at which oscillatory discharges took place varied, among different cells, between 16 and 142 Hz; however, 75% of the recorded cells discharged at frequencies between 20 and 50 Hz. From recordings in which two to four such cells were recorded simultaneously, evidence was found for multiple cells firing at the same frequency as well as for multiple cells firing at different frequencies. The precise timing of spike discharge in these cells makes them potential candidates to participate in timing functions thought to depend on the cerebellum 相似文献
20.
Carlo Mancini Giulio Pisani Alberta Azzi Maria Luisa Zerbini Giuliano Gentili Guillermo Mario Bisso MS participants 《Journal of clinical virology》2004,30(4):313-319
BACKGROUND: The importance of the standardisation of nucleic acid amplification technology (NAT) assays for the detection of hepatitis C virus RNA is well known today, as many studies carried out in different European countries attest. The results of a previous study performed in Italy (J. Clin. Virol. 1 (2003) 83) by the Italian Society of Clinical Microbiology (AMCLI) showed that the use of external reference standards and of multicentre collaborative studies significantly improves laboratory performance for the qualitative evaluation of HCV RNA. OBJECTIVES: the AMCLI organised a new study on the standardisation of both the qualitative and the quantitative evaluation of HCV RNA with NAT in order to improve the implementation of the diagnostic methods for HCV RNA detection. STUDY DESIGN: seventeen diagnostic centres of major Italian Hospitals participated in this quality control study. The study consisted of testing three panels, each made up of 10 coded samples including negative and positive samples. Positive samples contained four levels of HCV RNA (genotype 1). RESULTS AND CONCLUSION: Seven out of 510 qualitative results obtained were incorrect (1.4%), two false negative and five false positive. The results gave a sensitivity of 99.5% and a specificity of 95.8%. Regarding quantitative tests, the geometric mean (GM) and standard deviation (S.D.) could be calculated only for the three highest HCV RNA levels. The percentage of results within the range of GM +/- 0.5 log(10) varied from 91% to 100%. Some laboratories had some difficulty in the exact quantification of the lowest (3.00 log IU/ml) as well as of the highest viral levels (6.35 log IU/ml) values, very near to the limits of the dynamic range of the assays. The comparison of the results of this study with that previously carried out one confirms that a regular participation in external quality assessment (EQA) assures the achievement of a high proficiency level in the diagnosis of HCV infection. 相似文献