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51.
In 20 patients with unilateral cerebrovascular disease, regional cerebral blood flow (rCBF) was measured by F-18-fluoromethane inhalation and positron emission tomography (PET). The purpose was to study various strategies of rCBF data analysis that are currently used in SPECT and PET. Methods of quantitative data analysis standardize rCBF values relative to an intraindividual reference, and thus create ratios as estimators of rCBF in the ischemic regions-of-interest (ROI). These ratios were compared as well as the absolute rCBF values in the ischemic ROI graphically and by Spearman's rank correlation coefficient (r). The results demonstrated that previously reported methods of data analysis failed to represent rCBF in the ischemic ROI; r values were 0.467, -0.406, -0.453, and 0.329, respectively (N.S.). This failure was due to a more widespread reduction of rCBF even in patients with minimal ischemic deficits. In conclusion, previously reported strategies of rCBF analysis based on intraindividual standardization should not be used in patients with cerebrovascular disease since they may produce misleading results. 相似文献
52.
Changes in human ecology and behavior in relation to the emergence of diarrheal diseases, including cholera. 总被引:1,自引:0,他引:1 下载免费PDF全文
M M Levine O S Levine 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(7):2390-2394
Human populations throughout the world can be found in diverse conditions. A proportion of the population of developing countries lives in deprived conditions characterized by ramshackle housing, lack of piped water and sanitation, and widespread fecal contamination of the environment. Enteric infections, particularly due to bacterial pathogenes, are readily transmitted under these circumstances. In contrast, the majority of inhabitants of industrialized countries live in a sanitary environment that generally discourages the transmission of enteric pathogenes, particularly bacteria. In both these ecologic niches, changes in human ecology and behavior are leading to the emergence of certain enteric infections. Relevant factors in developing areas include urbanization (leading to periurban slums), diminished breastfeeding, and political upheaval that results in population migrations. In industrialized areas, large-scale food production (e.g., enormous poultry farms), distribution, and retailing (e.g., fast-food chains) create opportunities where widespread and extensive outbreaks of food-borne enteric infection can ensue if a breakdown in food hygiene occurs. 相似文献
53.
Consuming Passions: Feminist Approaches to Weight Preoccupation and Eating Disorders, edited by Catrina Brown and Karin Jasper. Toronto: Second Story Press, 1993, 459 pages, $16.95 paperback.
Binge Eating: Nature, Assessment, and Treatment, by Christopher G. Fairburn & G. Terrence Wilson. New York: Guilford Press, 1993, 420 pages, $40.00 相似文献
Binge Eating: Nature, Assessment, and Treatment, by Christopher G. Fairburn & G. Terrence Wilson. New York: Guilford Press, 1993, 420 pages, $40.00 相似文献
54.
S R Levine K M Welch J A Helpern M Chopp R Bruce J Selwa M B Smith 《Annals of neurology》1988,23(4):416-418
We report on a patient with a large ischemic hemispherical stroke studied serially by 31P nuclear magnetic resonance spectroscopy. Persistent hyperglycemia was associated with prolonged acidosis in ischemic brain and failure of high-energy phosphate metabolism to recover. These in vivo human data support the concept that hyperglycemia adversely affects ischemic brain metabolism, pH, and clinical outcome. 相似文献
55.
A Franco C Gonzalez O S Levine R Lagos R H Hall S L Hoffman M A Moechtar E Gotuzzo M M Levine D M Hone et al. 《Journal of clinical microbiology》1992,30(8):2187-2190
We examined envelope protein profiles, chromosomal restriction endonuclease digest patterns, and immune responses to envelope proteins for collections of Salmonella typhi strains isolated in Peru and Indonesia. Only minor differences in envelope protein patterns were apparent among strains. Strains from 7 of 20 Indonesian patients had a distinct chromosomal digest pattern compared with patterns of Peruvian and other Indonesian strains. Strains with this pattern carried the gene for the j flagellar antigen (H1-j); differences in response to envelope proteins of j and d strains were noted on immunoblot analysis. Our data suggest that there are genotypic and phenotypic differences among S. typhi strains. The clinical importance of these differences remains to be fully evaluated; however, in this study it was not possible to show a clear correlation between strain characteristics and disease severity. 相似文献
56.
Arnold J. Levine 《International journal of cancer. Journal international du cancer》1994,56(6):775-776
Linxian, China has some of the highest rates of esophageal/gastric cardia cancer in the world. In 1983, esophageal balloon cytology screening was performed in 3 communes in northern Linxian. Of the participants, 10,066 with no evidence of cancer were followed prospectively for 71/2 years to evaluate the ability of the initial cytologc diagnoses to identify individuals at increased risk for developing cancer of the esophagus or gastric cardia. A total of 747 incident cases of esophageal or cardia cancer and 322 deaths due to these tumors were identified during the follow-up period and used in this analysis. The risks for esophageal or cardia cancer incidence and mortality increased in parallel with the presumed severity of the 1983 Chinese cytologic diagnoses. After adjusting for potential confounding factors, relative risks for esophageal or cardia cancer incidence, by initial cytologic diagnosis, were normal = 1.00 (reference), hyperplasia = 1.25, dysplasia 1 = 2.20, dysplasia 2 = 4.22 and near-cancer = 5.96. Our results suggest that esophageal balloon cytology, as performed and interpreted in Linxian in 1983, successfully identified individuals at increased risk for developing cancer of the esophagus or gastric cardia. © 1994 Wiley-Liss, Inc. 相似文献
57.
Joanna Rumerman Stephen E. Rubesin M.D. Marc S. Levine William B. Long Igor Laufer 《Abdominal imaging》1988,13(1):200-202
A double-contrast upper gastrointestinal examination on a woman who had undergone endoscopic heater probe therapy one day earlier for multiple arteriovenous malformations revealed shallow, irregular, and linear ulcers at the sites of heater probe coagulation. Multiple shallow ulcers may therefore develop as a direct complication of heater probe therapy. Radiologists should be aware of this complication to avoid diagnostic confusion in these patients. 相似文献
58.
PURPOSETo analyze the MR characteristics of a series of patients with esthesioneuroblastoma and discuss the typical surgery and its postoperative MR appearance.METHODSThe MR studies of 15 patients with the pathologic diagnosis of esthesioneuroblastoma (also known as olfactory neuroblastoma) were retrospectively reviewed and correlated with CT and surgical findings. The postoperative MR studies of 10 patients who underwent craniofacial resection were also reviewed.RESULTSIn all cases the tumors arose in the superior nasal cavity and extended into the ethmoid cells. In some instances the tumors extended into the other paranasal sinuses, orbits, anterior cranial fossa, and cavernous sinus. The tumors were typically expansile and destructive in their growth patterns. Compared with brain gray matter, the tumors were hypointense on T1-weighted images and isointense to hyperintense on T2-weighted images. Nine tumors were heterogeneous and 6 were homogeneous. Contrast enhancement ranged from mild to marked. MR was useful for characterizing the various tissues and distinguishing fluid in the postoperative nasal cavity.CONCLUSIONSEsthesioneuroblastoma, although an uncommon tumor, may be suspected in lesions of the superior nasal cavity demonstrating both expansile and destructive growth properties. The MR findings are otherwise nonspecific. MR is the imaging modality of choice for depicting local tumor extension and evaluating for recurrence after craniofacial resection. 相似文献
59.
60.
A R Dresdale P L Kraft G Paone T McFarland T B Levine R delBusto S Lutz C Drost N A Silverman 《The Journal of cardiovascular surgery》1992,33(6):746-753
Allograft coronary artery disease (ACAD) is the major factor limiting long-term survival of cardiac transplant recipients (CTRs). Although cyclosporine based triple drug immunosuppression has not decreased the occurrence of ACAD, some preliminary data suggests that prophylactic antilymphocyte preparations may reduce the incidence of this problem. All CTRs at Henry Ford Hospital have uniformly received prophylactic Minnesota Antilymphocyte Globulin (ALG), thereby providing a unique opportunity to investigate this hypothesis. One hundred three CTRs were followed for a median duration of 34 months with annual angiograms begun one year after transplant. Patients who died without an angiogram were considered to have ACAD based on autopsy results or if their death was clinically suspicious. Ninety-two patients underwent at least one angiogram. Fourteen patients had abnormal angiograms. Nine patients were identified as having ACAD by non-angiographic criteria. Five had autopsy proven disease, 3 died suspiciously, and 1 underwent successful re-transplantation for ACAD. By Kaplan-Meier analysis, the risk of developing ACAD was 12% in 1 year, 16% in 2 years, 22% in 3 years, 26% in 4 years, and 29% in 5 years. Risk of ACAD increased with older recipient's age, higher triglyceride levels, and diabetes, but was not affected by active CMV infection, number of acute rejection episodes, and HLA mismatching. These results suggest that prophylactic ALG reduces the occurrence of ACAD. 相似文献