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Radiation of 2 MeV neutrons was used to induce conotruncal anomalies experimentally in chick. White leghorn eggs were exposed to a single dose of neutrons ranging from 50 to 250 rads at various stages of the development. Cardiovascular anomalies were found in 209 (40%) of 526 treated embryos; conotruncal anomalies (81/209 or 39%), simple VSD (56/209 or 27%), isolated aortic arch anomalies (69/209 or 33%) and others (3/209 or 1%). The conotruncal anomalies were induced at considerably high incidences by exposures during the 3rd day of incubation and the highest incidence was 74% in the cases malformed by 220 rads. The types of conotruncal anomalies observed were as follows: VSD with pulmonary overriding (52 cases), VSD with aortic overriding (11 cases), DORV (10 cases), truncus arteriosus (6 cases) and complete TGA (2 cases). Sixty (74%) of these cases had aortic hypoplasia, constituting coarctation or interruption complex similar to that seen in man. It is generally thought that the experimental production of complete TGA in chick appears to be impossible when utilizing ordinary teratogenic means. However, neutron radiation could induce this peculiar anomaly in chick.  相似文献   
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The interaction between CD27 and CD70 provides a costimulatory signal for T-cell survival. Although the role of CD27 signaling in CD8(+) T cells has been well defined, its role in CD4(+) T cells is relatively unknown. Here, we report that CD70 is specifically expressed on differentiated T-helper (Th)1 cells, but not on Th2 cells. Upon activation, CD70 expression increased markedly on Th1 cells, but remained undetectable on Th2 cells. We demonstrate that CD27 is involved in naive T-cell expansion in Th1-type, but not in Th2-type, immune responses as in vivo treatment with anti-CD70 monoclonal antibody at induction resulted in a significant reduction of delayed-type and contact hypersensitivity responses, but not asthmatic responses. In both Th1-type responses, during the priming phase, CD70 was detected at earlier time points on dendritic cells (DCs) and at later time points on CD4(+) T cells. Our results indicate that CD70 may be useful as a marker to distinguish Th1 from Th2 cells. More importantly, CD27 function may be controlled by the differentially regulated kinetics of CD70 expression on DCs and CD4(+) T cells, and Th1 cell-specific CD70 expression may be involved in an amplification loop for polarized Th1-type immune responses through T cell-T cell interactions.  相似文献   
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The biomechanical influences of head posture on the cervical column and craniofacial complex during masticatory simulation were quantified using three-dimensional (3D) finite element analysis (FEA). Three types of finite element model (FEM) were designed to examine relationships between the position of the head and malocclusion. Model A was constructed to have a standardized cervical column curve, model B a forward inclined posture, and model C a backward inclined posture. The results of the spinal displacements revealed that model B moved in a forward direction and model C in a backward direction during masticatory simulation. The stress distributions on the cervical column (C1-C7) for models A, B, and C showed differences; stress converged at the atlas in model A, high-level stresses were observed at the spinous processes of C6 and C7 in model C, and the stress converged at the anterior edge in the vertebral body of C4 of model B. Stress distribution on the occlusal plane and maxillofacial structure did not show absolute differences among the three models. Alteration of head posture was directly related to stress distribution on the cervical column, but may not always directly influence the occlusal state.  相似文献   
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Effects of texture of food on chewing patterns in the human subject   总被引:4,自引:0,他引:4  
To elucidate the effects of food character on chewing patterns in humans, the electromyographic activity (EMG) of the chewing muscles and also the jaw movements were recorded in twenty-nine young subjects during ordinary chewing of five different foods. The results obtained were as follows. (a) The harder food materials showed a higher amplitude of the masseter EMG than the softer ones. (b) Concerning the number of chewing strokes and the elapse of time until the last swallowing action, subjects could be divided into two groups. (i) In the first major group, the number of chewing strokes and chewing time until the last swallowing action increased following increase of hardness of the food. This suggests that chewing force and chewing movements may be strongly influenced by the texture of food, especially its hardness. Further, the degree of pulverization of eating materials appears to be the major factor in controlling the swallowing action. (ii) In the second minor group, the chewing strokes and the chewing time were less influenced by the hardness of food. Here, a certain number of chewing strokes could be stimulating the swallowing centre in the brain and so induce swallowing, regardless of the degree of pulverization of the food.  相似文献   
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Ovarian mucinous cystadenomas are benign epithelial neoplasms that occur most often in the third to sixth decade of life. Ovarian mucinous cystadenoma can be classified into 3 categories (benign, borderline malignancy, malignancy) based on histopathologic evaluation. Premenarchal cases of ovarian mucinous cystadenoma of borderline malignancy are exceedingly rare. To the best of our knowledge, there have been only 4 reported cases of borderline ovarian mucinous cystadenoma prior to 2009. Here we report a 13-year-old premenarchal girl with a giant mass occupying almost the whole of the abdomino-pelvic cavity.  相似文献   
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PURPOSE: Thirty-nine renal cell carcinoma patients with bony metastasis were intensively treated, primarily with immunotherapy using natural type interferon-alpha (IFN-alpha) continuous subcutaneous injection in combination with surgical resection and radiation therapy. Long-term survival was achieved, including three patients with complete response. The results of this study are presented. METHODS: The mode of administration of IFN-alpha was as follows: natural-type IFN-alpha (25,000,000 IU) was dissolved in 60 mL of distilled water and administered via continuous subcutaneous injection (0.5 mL/h) as 'one course of the treatment'. Two courses of IFN-alpha therapy were given 2 weeks preoperatively, while 13 courses of IFN-alpha therapy were given postoperatively (one course per week). Thus, 15 courses of IFN-alpha therapy were administered during the trial period. Thereafter, IFN-alpha therapy was repeated either every week or every other week depending on the condition of the patient. Additionally, blood levels of IFN-alpha were monitored for four patients following initiation of IFN-alpha continuous subcutaneous injection therapy. RESULTS: Immediately after injection of IFN-alpha, blood levels of IFN-alpha started to rise, reaching 40.5 IU/mL on average at 24 h after initiation of IFN-alpha therapy. Thereafter, blood levels of IFN-alpha remained high and measurable blood levels of IFN-alpha were maintained for up to 24 h after completion of IFN-alpha injection. As a whole, IFN-alpha was detectable for 6-8 days and Cmax (maximum blood concentration of IFN) was 167 IU/mL. Thirty-nine patients with bony metastases were treated as follows: IFN mono-therapy (19 patients), IFN and radiation therapy (15 patients) and IFN and surgical resection of bony metastases (five patients). Fourteen patients survived and the details of these 14 patients are as follows: complete response in three cases, partial response in two, no change in six and progressive disease in three. Twenty-five patients died of renal cell carcinoma. The overall 5-year survival rate was 35.0%. CONCLUSIONS: These findings indicate that IFN-alpha continuous subcutaneous injection therapy is a useful modality for renal cell carcinoma patients with bony metastasis if administered in combination of radical nephrectomy and radiation therapy.  相似文献   
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