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991.
INTRODUCTION: An assessment of transfusion medicine knowledge and practice in Canada was carried out over a 3-week period. METHODS: Fifty-five questions were posed to evaluate both basic information on blood and blood products and on clinical use. The form was distributed through the Canadian Society for Transfusion Medicine with designated individuals asked to handle regional distribution. Some used provincial mailing lists, others distributed within each hospital. Approximately, 2000 forms were sent, including 500 in French. RESULTS: A total of 294 forms were returned; answers were recorded as 'correct', 'incorrect', 'no answer' or with 'added comments'. Overall, 52% of the questions were answered correctly or were answered with qualifying comments. In clinical practice questions, 63% were answered correctly or with qualifying comments. Basic knowledge questions drew correct answers in 37% of the cases. Several issues were answered poorly. The volume of an apheresis plasma unit was correctly estimated by less than 10% of respondents with many understanding the volume (500-600 mL) by as much as 300-400 mL. Anaesthesiologists responded most often (21%); few haematologists participated (4%). Provincial response varied: most were received from Ontario (30%) and British Columbia (22%). CONCLUSIONS: The answers show that clinical application of transfusion is generally accompanied by a questioning process - it is not entirely by rote. Basic knowledge about products needs improvement. 相似文献
992.
993.
Simultaneous immediate placement and immediate loading of implants in the maxilla: a case presentation 总被引:1,自引:0,他引:1
The standard three- to six-month healing time for implants is no longer an absolute. In selected cases, it is now possible to load the implants in fewer than two months; and, in some cases, immediate loading is possible. This article contains a case study showing that with careful patient selection, immediate loading appears to be an acceptable technique. 相似文献
994.
Immediate placement in extraction sites followed by immediate loading: a pilot study and case presentation 总被引:3,自引:0,他引:3
The purpose of the study was to compare the results of implants immediately loaded in edentulous sites with implants loaded immediately in extraction sites. Since December 1998, we selected a small group of patients for immediate or early loading. Seventy-five implants were placed in nine jaws of seven patients. Two of the patients received implants in both the maxilla and mandible. Of the 75 implants placed, 29 were placed in immediate extraction sites. Twenty-six of the 29 that were placed in immediate extraction sites were loaded in less than 3 weeks. Of the 75 implants placed, 62 were loaded early (less than 3 weeks). Two implants have been lost. The remaining 13 implants were buried and allowed to heal in the customary manner. None of the buried implants failed. One of the implants lost was in an extraction site and one was in a nonextraction site. Of the 33 implants that were placed in edentulous areas and immediately loaded, one was lost. This is compared with the 29 implants placed in extraction sites that were immediately loaded. We conclude that the success rates for implants immediately loaded in extraction sites and edentulous sites are comparable. 相似文献
995.
996.
Lamin expression in human adipose cells in relation to anatomical site and differentiation state 总被引:2,自引:0,他引:2
Lelliott CJ Logie L Sewter CP Berger D Jani P Blows F O'Rahilly S Vidal-Puig A 《The Journal of clinical endocrinology and metabolism》2002,87(2):728-734
Familial partial lipodystrophy-Dunnigan variety (FPLD) is an autosomal dominant form of lipodystrophy resulting in a loss of sc fat from the trunk and limbs with retention of fat in the visceral depots, face, and neck. Specific point mutations in the gene encoding the nuclear lamina proteins, lamins A and C, have been established to cause this syndrome. We undertook studies to determine which members of the lamin family were expressed in human fat cells, to examine the effect of differentiation state on lamin A and C expression in human preadipocytes, and to test the hypothesis that regional variation in lamin A/C expression might underlie the stereotyped anatomical pattern of FPLD. Lamins A, C, and B1, but not B2, were expressed in sc mature human adipocytes. Subcutaneous preadipocytes expressed all four lamins, with lamin A and C expression increasing with ex vivo differentiation. Consistent with previously reported resistance to ex vivo differentiation, omental preadipocytes did not show an increase in lamin A or C mRNA under these conditions. Lamin A/C mRNA levels were similar in isolated mature adipocytes and preadipocytes from omental, sc, and neck sites. However, lamin C was consistently lower, and the ratio of lamin A/C mRNA was higher in sc mature adipocytes compared with omental mature adipocytes. We conclude that the depot-specific pattern of lamin A/C expression does not provide clues to the mechanism of FPLD. Nonetheless, these studies provide new information regarding the expression of lamin isoforms in normal human adipose cells, which will inform future studies of the molecular pathogenesis of FPLD. 相似文献
997.
998.
Localization of language function in children: results of electrical stimulation mapping 总被引:7,自引:0,他引:7
OBJECT: The authors examined the localization of language sites and the frequency of naming errors at these sites in a population of children undergoing electrical stimulation mapping during surgeries in which epileptic foci and dominant hemisphere neoplasms were resected. The frequency with which essential language sites were found (that is, "the frequency of language sites") in children was compared with that of a population of adults who had undergone this procedure, to assess the relationship of age to the distribution of essential areas for language. METHODS: The results of electrical stimulation mapping to determine sites of naming and speech arrest in 26 children ranging in ages from 4 to 16 years are presented in this report. Mapping was performed in the intraoperative setting in eight patients and in the extraoperative setting, by stimulation across a subdural grid, in 18 patients. The frequency and distribution of essential language areas were analyzed in populations of different ages and according to the method used to obtain the map. Considerable variability was found in the localization of language sites. When the language site distribution in pediatric patients was compared with the language site distribution found previously in a population of patients older than 16 years of age, a relative paucity of language sites was found in all perisylvian cortices in the younger age group. This relationship was also found within the group of patients 16 years of age and younger, when segregated into two groups: those patients 8 years of age or younger, and those patients between 9 and 16 years of age. These findings are relevant to theories of the intrahemispheric organization of the cortex devoted to language function. CONCLUSIONS: The differences found between groups of younger and older patients in the frequencies of sites where stimulation produces naming errors was identified suggests the possibility that, with advancing age, maturational processes contribute new foci of cortex essential for language. 相似文献
999.
BACKGROUND: The aim of this study was to develop models that allow serial, noninvasive imaging of human prostate cancer cells in immunodeficient mice using a dedicated small animal positron emission tomography scanner (microPET). METHODS: LNCaP tumor cells were stably transduced ex-vivo with the mutant herpes simplex virus type 1 thymidine kinase (HSV-sr39tk) PET reporter gene and green fluorescent protein (GFP). The stably transduced LNCaP cells were then enriched via fluorescent cell sorting and implanted into SCID mice. Beginning 2 weeks after tumor cell inoculation, mice were repeatedly scanned by microPET performed 1 hr after tail-vein injection of approximately 200 muCi Fluorine-18 labeled penciclovir ((18)F-FHBG). PET-images were correlated to tumor size, % injected dose (ID)/g tumor tissue, PSA levels, autoradiography, and histology. RESULTS: Monitoring LNCaP xenografts using microPET and our reporter gene approaches is feasible. MicroPET was capable of detecting subcutaneous tumors as small as 3 mm in diameter (approximately 0.2% ID/g). The magnitude of (18)F-FHBG-uptake in PET-images correlated with the tumor volumes and the serum PSA levels. Other non-HSV1-TK-specific tracers were also studied. While (18)F-flurodeoxyglucose ((18)F-FDG) gave poor imaging results in LNCaP cells, (11)C-acetate gave satisfactory images. CONCLUSIONS: We demonstrated the feasibility of monitoring prostate cancer xenografts in a mouse model using microPET and the HSV1-sr39tk PET reporter gene/(18)F-FHBG reporter probe system. Extension of this approach may allow repetitive imaging of tumor metastases. 相似文献
1000.
At postoperative day 10 of a percutaneous nephrolitholapaxy for a large stone in the right renal pelvis of a 78-year-old female patient, persistent gross hematuria, requiring blood transfusions, occurred. Selective renovasography showed a pseudoaneurysm of the branch of a segmental artery close to the lower renal calices. Subsequent selective placement of two "steel-coils" in the feeding artery through a coaxial catheter system resulted in complete and stable occlusion without loss of renal parenchyma. Thereafter, bleeding immediately stopped and the patient suffered no further complications. This tool of interventional radiology should be kept in mind before open surgery is considered. 相似文献