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11.
Between 1984 and 2000 in the Thoracic Surgery Centre pneumonectomies were performed in 947 patients. Postpneumonectomy empyema (PE) occurred in 67 (7%) patients. The aim of this paper were: analysis the reasons of postpneumonectomy empyema appearance, defined bacterial flora, clinical course and optimal management. The causes of PE were: pleural cavity haematoma (20 patients-29.8%), wound suppuration (18 patients-26.8%), bronchial fistula (31 patients-46.2%). These complications appeared singly or together in 49 (73.1%) patients. In 2 (3.0%) patients a long treatment in the Intensive Care Unit because of postoperative shock was the cause of infection. In 3 (4.5%) cases the cause of empyema was associated with infection during the operation. In 13(19.4%) cases the cause of empyema was not established. In 55 patients infections of pleural cavities were diagnosed in the first 8 weeks after operations. In 12 patients empyemas were established later. 12 (17.9%) patients died during the analyzed 1 year period after operation. In 18 (26.9%) patients infections were caused by only one bacterial strain and in 49 (73.1%) by two or three bacterial strains. The different methods of treatment (thoracentesis, drainage, operation) depending on general condition of patient were done. 相似文献
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13.
Waldemar Dabrowski Jerzy Andrzejewski Aleksandra Bogunowicz 《Medical microbiology and immunology》1972,158(2):113-120
Zusammenfassung Das Vacciniavirus vermehrt sich schnell in den Organen von 1 tägigen Ratten, und die Tiere verenden am 2. oder 3. Tag nach der Infektion. In den Organen von 7 tägigen Ratten kann sich das Virus anfangs vermehren, später wird es aber eliminiert und die Tiere überleben. Bei 15tägigen Ratten wird das Virus eliminiert und die Tiere verenden nicht.Eintägige Ratten, die vor der Infektion Makrophagen erwachsener Tiere erhalten haben, kamen nicht ad exitum. Die Makrophagen von erwachsenen Ratten haben im Gegensatz zu Makrophagen von jungen Tieren die Fähigkeit, das phagozytierte Virus zu inaktivieren.Es wird daraus der Schluß gezogen, daß für die hohe Empfindlichkeit junger Ratten gegenüber Vacciniavirusinfektionen die funktionelle Unreife ihrer Makrophagen verantwortlich ist.
The role of macrophages in the pathogenicity of vaccinia virus for young rats
Summary Vaccinia viruses grew rapidly in organs of 1-day-old rats, and the animals died 2 or 3 days after infection. In the organs of 7-day-old rats the viruses replicated initially, but were later eliminated and the animals survived. The 15-day-old rats were capable of eliminating the viruses completely and did not die. When macrophages of adult animals were transferred to 1-day-old rats before infection the rats did not die. The macrophages of adult rats destroyed phagocytized viruses while those of young animals did not.The results suggest that this susceptibility of young rats to vaccinia virus infection is due to the functionally immature state of their macrophages.相似文献
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15.
Prokopowicz M Banecki B Lukasiak J Przyjazny A 《Journal of biomaterials science. Polymer edition》2003,14(2):103-118
The paper investigates the conformational stability of bovine serum albumin (BSA) and fibrinogen during 24-h incubation in turn with a linear silicone polymer (polydimethylsiloxane (PDMS)), with linear silicone oligomers (hexamethyldisiloxane and octamethyltrisiloxane) and with cyclic silicone oligomers (octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5)). Ten-fold and 100-fold excesses of siloxanes with respect to the proteins were used. Using fluorescence spectroscopy of tryptophan located in the domain of proteins and fluorescence of 8-anilino-1-naphthalenesulfonic acid (1,8-ANS), which interacts with hydrophobic domains of proteins, changes in the tertiary structure of the protein were recorded. The results demonstrated that BSA does not change its native form during 24-h incubation with siloxanes. In contrast, the tertiary structure of fibrinogen was found to be altered by both short-chain linear siloxanes: (hexamethyldisiloxane and octamethyltrisiloxane) and long-chain PDMS. The changes can be observed only at a 100-fold excess of siloxanes with respect to the protein. No conformational changes in fibrinogen exposed to cyclic siloxanes were observed. 相似文献
16.
Differential scanning calorimetry, dynamical mechanical, and spin probe measurements were conducted to study relaxation and soft-segment crystallization phenomena in block copoly(ether-ester) elastomers obtained through transesterification and melt polycondensation of dimethyl terephthalate, 1,4-butanediol and poly(ethylene oxide). The elastomers investigated differed both in molecular weight of the poly(ethylene oxide) used as well as in their ratio of hard to soft segments. It was found that a crystallization process of the soft-segment phase does not occur for oligoethers with a molecular weight lower than 1000. The spin probe method can be used to monitor the melting process and additionally it supplies information on the relaxation processes taking place in the amorphous part of the soft phase. Some data on the crystallization of the rigid phase are also given. 相似文献
17.
Ryszard Andrzej Jedrychowski Jerzy Andrzej Sokal Jadwiga Chmielnicka 《Archives of toxicology》1984,55(3):195-198
Rats were subjected to 4 h continuous or intermittent exposure to vinyl chloride (VC) at different time-weighted average concentrations (15, 50, 150, 500 and 15,000 mg/m3). Hepatic non-protein sulfhydryl content (NPSH) and excretion of thiodiglycolic acid (TdGA) in urine were determined. VC at concentrations from 50 mg/m3 to 15,000 mg/m3 caused a dose-dependent depression of NPSH, but no difference in the magnitude of this depression induced by continuous or intermittent exposure at the same average concentration of VC was noted. At average concentrations of 50 mg/m3 and 150 mg/m3, the urinary excretion of TdGA under continuous exposure did not differ from that under intermittent exposure, whereas at VC concentrations of 500 mg/m3 and 15,000 mg/m3 it was higher following continuous exposure. 相似文献
18.
Low doses of oxytocin facilitate social recognition in rats 总被引:7,自引:0,他引:7
Social recognition of juveniles by adult male residents has been shown to be modulated by neurohypophyseal hormones. The decrease of social investigation behavior during a second encounter with the same juvenile serves as index for social recognition. In the present study it was found that low doses (0.09–6.0 ng · kg–1) of oxytocin (OXT) given subcutaneously dose dependently facilitated social recognition. The effect of OXT appeared specific, since no change in social investigation was found when a novel juvenile was tested during the second encounter. No disturbances of social recognition by the low doses of OXT could be detected, in contrast to higher doses of this hormone. Other neurohypophyseal hormones, vasopressin and vasotocin, did not facilitate social recognition when tested in the same range of low doses. 相似文献
19.
Jerzy Silberring Waldemar Gołda Zbigniew Szybinski 《European journal of nuclear medicine and molecular imaging》1976,1(3):155-158
In this paper attempts were made towards the optimalization and the control of some parameters of the RIA reaction.Basing on the law mass action, as well as on the Scatchard's and Sips's equations, the equilibrium constants for the reversible reaction: insulin-125I-antibody for different incubation temperatures were calculated. Moreover a characteristic of the antiinsulin antibody by means of the heterogeneity coefficient was done, as well as the values of the thermodynamic function increments were calculated, which made possible to point out explicitly the optimal shape of the standard curve. 相似文献
20.
Regine Schneider-Stock Carsten Boltze Jerzy Lasota Markku Miettinen Brigitte Peters Matthias Pross Albert Roessner Thomas Günther 《Journal of clinical oncology》2003,21(9):1688-1697
PURPOSE: Gastrointestinal stromal tumors (GISTs) represent a distinctive (but histologically heterogeneous) group of neoplasms, the malignant potential of which is often uncertain. To determine the prognostic relevance of p16INK4 alterations in GISTs, we investigated a larger group of GISTs and correlated the genetic findings with clinicopathological factors and patient survival. MATERIAL AND METHODS: We evaluated the methylation status of the promotor by methylation-specific polymerase chain reaction (PCR), the presence of mutations by PCR-SSCP-sequencing, the loss of heterozygosity at the p16INK4 locus (using the c5.1 marker), and the immunohistochemical expression of p16INK4 protein in 43 GISTs in 39 patients. RESULTS: p16INK4 alterations were found in 25 of 43 GISTs (58.1%), with benign, borderline, or malignant GISTs showing no differences in the type and frequency of alteration. p16INK4 alterations were correlated with a loss of p16INK4 protein expression (P <.01). Patients who had tumors with p16INK4 alterations had a poorer prognosis than patients with tumors without such alterations (P =.02). There was a high predictive value for p16INK4 alterations only in the group of benign and borderline GISTs (P <.01) with regard to clinical outcome. Univariate Cox's proportional hazard regression analysis revealed a strong correlation between p16INK4 alterations, tumor size, mitotic index, and overall survival (P <.02), whereas multivariate Cox's analysis confirmed only p16INK4 alterations as an independent prognostic factor. CONCLUSION: We believe that the evaluation of p16INK4 alteration status is a helpful prognosticator, particularly in the benign and borderline groups of GISTs. 相似文献