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21.
The ability of antisera to guinea-pig C3 to inhibit the Arthus and local Shwartzman reactions was studied. They were found to reduce the non-haemorrhagic component of the active and reversed passive Arthus reactions and to delay the appearance of the haemorrhage in the active Arthus reaction. Cobra venom factor, however, had no effect on the non-haemorrhagic components of these reactions and only delayed the appearance of the haemorrhage of the active Arthus reaction. There appeared to be a correlation between the serum complement level and the time taken for the haemorrhage to appear, and between the circulating platelet count and the extent of the non-haemorrhagic, oedematous component of the reaction. The haemorrhagic component of the local Shwartzman reaction was not affected by decomplementation with cobra venom factor. The ability of the antisera to inhibit the haemorrhage of the Shwartzman reaction was not dependent on lowering the serum complement titre. However, the haemorrhage was inhibited if the circulating platelet count was also reduced to very low numbers. Antiserum to zymosan alone had the same effect as anti-beta1C/beta1A globulin (zymosan) in blocking the reaction, although it did not alter the complement levels or the platelet counts. The possibility of an immunological cross-reactivity between zymosan and endotoxin in this action is discussed. 相似文献
22.
Immunoglobulin molecules on the surface of mouse thymus cells have been shown by immunofluorescence. Ninety-five to 100 per cent of thymus lymphocytes were found to bind polyvalent rabbit anti-mouse immunoglobulin, although the density of the fluorescence was much less than that on the surface of B lymphocytes derived from the spleen.
Two purified antisera, an anti-IgM and an anti-kappa chain serum, also stained the cells.
The resynthesis of these immunoglobulin molecules in vitro was demonstrated after they had been removed with pronase.
相似文献23.
24.
A Aronstam P J Kirk J McHardy J W Culver-James D S McLellan P Turk S G Rainsford M Slattery 《Journal of clinical pathology》1977,30(1):65-67
Factor VIII-containing materials were administered to four severely affected haemophiliacs twice weekly in doses calculated to raise the factor VIII level to either 15% or 30% of average normal. The pooled results from those patients with statistically similar baseline bleeding frequencies showed a significant reduction in bleeding frequency on both doses in the first 48 hours. The 30% dose produced a more significant reduction than the 15% dose in the first 24 hours, but there was no significant difference between the two doses in the second 24 hours. It appears that to reduce the bleeding frequency of severely affected haemophiliacs by 60% would require a two-and-a-half-fold increase in therapeutic materials. A 90% reduction would need nine times the amount of material currently in use. 相似文献
25.
Immunological Unresponsiveness in Guinea Pigs: II. The Effect of Unresponsiveness on the Development of Delayed Type Hypersensitivity to Protein Antigens 总被引:4,自引:0,他引:4 下载免费PDF全文
Guinea pigs were rendered incapable of making circulating antibody against bovine serum albumin (BSA) or human gamma globulin (HGG), by prenatal and/or neonatal contact with these antigens. They were then treated with a water in oil emulsion of picryl BSA, or with HGG in Freund's adjuvant, or with HGG precipitated with excess rabbit antibody and suspended in a water in oil emulsion, such as to produce a state of delayed hypersensitivity to BSA or HGG respectively in control animals. The guinea pigs which would not make antibody failed to become hypersensitive to these antigens. In one group of unresponsive animals treatment with HGG in Freund's adjuvant resulted in antibody production, but no phase of delayed hypersensitivity was observed. 相似文献
26.
The nature of the suppressive activity in the peritoneal exudate cells (PEC) of guinea-pigs immunized with dinitrophenyl bovine gamma globulin (DNP50-BGG) was investigated. A method was developed to isolate from the peritoneal exudate large numbers of macrophages. Using density gradient centrifugation on Percoll it was possible to obtain a population of cells which contained over 90% macrophages. This macrophage preparation was found to respond to lymphokine but to be incapable of passively transferring delayed hypersensitivity reactions. When these immune macrophages were transferred into antigen immunized animals, which had been pretreated with cyclophosphamide (CY), the skin reactions were suppressed to the same extent as when the total PEC was transferred. PEC from guinea-pigs immunized with ovalbumin in Freund's incomplete adjuvant did not suppress the skin reactions in CY-pretreated DNP50BGG immunized animals. However, in contrast, macrophages from these animals did suppress the skin reactions in the recipient guinea-pigs indicating that the macrophage suppression was not antigen specific. 相似文献
27.
Uta Landy Jema K Turk Kristin Simonson Katheryn Koenemann Jody Steinauer 《Contraception》2021,103(5):305-309
ObjectiveTo summarize the effects of routine, opt-out abortion and family planning residency training on obstetrics and gynecology (ob-gyn) residents’ clinical skills in uterine evacuation and intentions to provide abortion care after residency.MethodsData from ob-gyn residency programs supported during the first 20 years of the Kenneth J. Ryan Residency Training Program in Abortion and Family Planning were analyzed. Postrotation surveys assessed residents’ training experiences and acquisition of abortion care skills. Residency program director surveys assessed benefits of the training to residents and the academic department from the educators’ perspectives.ResultsA total of 2775 residents in 89 ob-gyn programs completed postrotation surveys for a response rate of 72%. During the rotation, residents – including those who only partially participated – gained exposure to and skills in first- and second-trimester abortion care. Sixty-one percent intended to provide abortion care in their postresidency practice. More than 90% of residency program directors (97.5% response rate) reported that training improved resident competence in abortion and contraception care and 81.3% reported that the training increased their own program's appeal to residency applicants.ConclusionOver 20 years, the Ryan Program has supported programs to integrate abortion training to give ob-gyn residents the skills and inspiration to provide comprehensive reproductive health care, including uterine evacuation and abortion care, in future practice. Residency program directors noted that this integrated training meets resident applicants’ expectations.ImplicationsRyan Program residents are trained to competence and are prepared, both clinically and in their professional attitudes, to care for women's reproductive health. 相似文献
28.
A few weeks after mice were injected i.v. with 10(8) live Mycobacterium bovis, BCG, the antibody response of their spleen cells to SRBC in vitro was comparable with the response of cells from untreated mice. Addition of BCG organisms to the culture vessels resulted in enhanced antibody-forming cell (AFC) responses by the primed cells but not by the cells from the untreated mice. No evidence was found for a direct stimulation of B cells and cell depletion experiments suggested macrophages were directly involved. BCG added to the cultures up to 68 h after they were set up, but not later, still caused enhancement. No enhancement was found when DNP-Ficoll was used as antigen. The ability to stimulate the anti-SRBC response was not restricted to the organism used for priming. Enhancement was also found if C. parvum or M. leprae were added to BCG-primed cells and if BCG was added to C. parvum-primed cells. The relevance of the results to the search for a leprosy vaccine is discussed. 相似文献
29.
30.