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21.
22.
Rosen Raymond C. Kostis John B. Jekelis Albert Taska Lynn S. 《Archives of sexual behavior》1994,23(2):135-152
Antihypertensive drugs are commonly associated with adverse side effects in both clinical and laboratory studies. We investigated the sexual sequelae of several major classes of antihypertensive drugs (e.g., beta blockers, central alpha agonists, diuretics) in normal males and in hypertensive patients. We compared the effects of four widely used agents (methyldopa, propranolol, atenolol, hydrochlorothiazide-triamterene) and placebo, in a selected sample of 21 sexually dysfunctional male hypertensives, 13 of whom completed all five phases of the study. Each study drug was administered for a 1-month treatment period, followed by a 2-week, single-blind washout phase, according to a randomized, Latin square crossover design. Dependent variables for the study included a broad range of hormonal, NPT, and self-report measures of sexual response. Results indicated a lack of consistent drug effects on measures of sexual response, although more frequent sexual and nonsexual side effects were observed with methyldopa and propranolol. As in our previous studies, age was negatively correlated with both hormonal and NPT measures, whereas changes in blood pressure were not significantly related to sexual function scores. Results do not support the hypothesis that sexually dysfunctional males are at greater risk for adverse sexual sequelae when treated with centrally active agents or diuretics. 相似文献
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S Trottier K Stenberg I A Von Rosen C Svanborg 《The Pediatric infectious disease journal》1991,10(8):578-584
The role of Haemophilus influenzae in acute purulent conjunctivitis was studied during an outbreak among children in day care. Five day-care centers contributed 20 cases and 35 controls. All the children were subjected to culture of the nasopharynx and the eyes. H. influenzae was carried in the nasopharynx of 53% of the children (range between day care centers, 20 to 91%). Of the 20 children with acute conjunctivitis 8 had eye cultures positive for H. influenzae, 2 had Moraxella and the remaining were culture-negative. Ten colonies of H. influenzae were isolated from each positive culture and identified by capsular type, biotype and multi-locus enzyme electrophoresis. All but one of the isolates were nonencapsulated. They belonged to 4 biotypes and 8 electrophoretic types. The same strain was recovered from the eyes and nasopharynx of the symptomatic children, suggesting that the H. influenzae in the eyes originated from the nasopharynx. There was no evidence for spread of the same H. influenzae strains between day-care centers. Even within each center the Haemophilus strains recovered from the eyes varied among the symptomatic children. The in vitro capacity to attach to oropharyngeal epithelial cells was not increased among the H. influenzae recovered from the eyes. The results question if the majority of conjunctivitis cases were caused by H. influenzae and suggested that eyes were colonized with the nasopharyngeal carrier strain rather than infected by an isolate with special virulence for the eye. 相似文献
26.
Perioperative blood transfusion and determinants of survival after liver resection for metastatic colorectal carcinoma. 总被引:26,自引:0,他引:26
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C B Rosen D M Nagorney H F Taswell S L Helgeson D M Ilstrup J A van Heerden M A Adson 《Annals of surgery》1992,216(4):493-505
The authors reviewed their institutional experience with liver resection for metastatic colorectal carcinoma to (1) determine whether perioperative blood transfusion affects survival; (2) identify prognostic determinants; and (3) estimate the patient requirement for a prospective randomized trial designed to demonstrate efficacy of liver resection. Two hundred eighty consecutive patients treated by potentially curative liver resection between 1960 and 1987 were included. Data were obtained for all but 10 patients for at least 5 years after operation or through 1990. Actuarial survival curves related to potential prognostic determinants were analyzed with the log-rank test. Overall, survival was 47 +/- 3% at 3 years and 25 +/- 3% at 5 years, including 4% 60-day operative mortality rate. Eighty-one patients who did not receive blood 7 days before to 14 days after operation had 60 +/- 6% 3-year and 32 +/- 6% 5-year survival compared with 40 +/- 4% and 21 +/- 3% survival rates for 183 patients who received at least one unit (p = 0.03, operative deaths excluded). Extrahepatic disease (p = 0.015), extrahepatic lymph node involvement (p = 0.002), satellite configuration of multiple metastases (p = 0.0052), and initial detection by abnormal liver enzymes (p = 0.0005) were associated with poor survival rates. Synchronous presentation of metastatic and stage B primary disease was associated with a favorable prognosis (p = 0.003). The requirement for a prospective randomized trial estimated by an exponential survival model would be 36, 74, 168, or 428 patients if 5-year survival without resection were 1, 5, 10, or 15%. We conclude that (1) perioperative blood transfusion may be adversely associated with survival; (2) extrahepatic disease, extrahepatic lymph node involvement, satellite configuration, and initial detection by clinical examination or a liver enzyme abnormality portend a poor prognosis; and (3) a prospective randomized trial of liver resection is impractical because of the large patient requirement, at least by a single institution. 相似文献
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Summary Meiotic progeny of Chlamydomonas reinhardtii normally receive chloroplast genomes only from the mt
+ parent. However, exceptional zygotes, which transmit the chloroplast genomes of both parents or, more rarely, only those of the mt
- parent, arise at a low frequency. Mutations at the mt
+-linked mat-3 locus were found previously to elevate the transmission of chloroplast genomes from the mt-parent, resulting in a much higher than normal frequency of exceptional zygotes. In this paper we demonstrate that an ultraviolet-sensitive nuclear mutation mapping at the uvsE1 locus, which is unlinked to mating type, also promotes chloroplast genome transmission from the mt
- parent. This mutant, which was previously shown to reduce recombination of nuclear genes in meiosis, acts synergistically which the mat3-3 mutation to produce an extremely high frequency of exceptional zygotes. Through the use of restriction fragment length polymorphisms existing in the chloroplast genomes of C. reinhardtii and the interfertile strain C. smithii, we show that chloroplast DNA fragments from the mt
- parent normally begin to disappear shortly after zygote formation. However, this process appears to be blocked totally in the absence of wild-type uvsE1 and mat-3 gene products. Our findings are consistent with the hypothesis that both gene products contribute to the mechanism responsible for uniparental inheritance of the chloroplast genome from the mt
+ parent. 相似文献
29.
A. Gregory Sorensen Andrew L. Tievsky Leif Ostergaard Robert M. Weisskoff Bruce R. Rosen 《Journal of magnetic resonance imaging : JMRI》1997,7(1):47-55
Contrast agents have greatly expanded the role of MR imaging (MRI) to allow assessment of physiologic, or “functional,” parameters. Although activation mapping generally does not require contrast agents, other forms of functional MRI, including mapping of cerebral hemodynamics (eg, perfusion imaging), are best done with the use of contrast agents. Serial echo planar images are obtained after bolus injection of lanthanide chelates. Application of susceptibility contrast physics and standard tracer kinetic principles permits generation of relative cerebral blood volume maps. Deconvolution of cerebral blood flow and mean transit time parameters is also possible within technical limitations. By using diffusion and perfusion pulse sequences, an imaging correlate to the ischemic penumbra can be identified. Functional MRI perfusion imaging of intraaxial tumors is analogous to positron emission tomography for delineation of metabolic activity, yet may be even more sensitive to neovascularity and possesses improved image quality. Clinical applications include biopsy site selection and postirradiation follow-up. Further improvements in data analysis and map generation techniques may improve diagnostic accuracy and utility. 相似文献
30.
. We invited Dr Peplau to provide a personal reflection on the recent history of psychiatric nursing and her thoughts on immediate challenges facing the profession. The paper is an individual scholar's commentary on the way that psychiatry has waxed and waned over the years, in relation to nursing. This historical review discovers and reports a challenge to current practice. Dr Peplau describes a professional shift that is pulling nurses toward the subordinate role observed earlier this century. The paper draws attention to how contemporary practice can be positively influenced, e.g., by giving a structure to the allocation and conduct of nurse–patient time. 相似文献