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61.
The Public Health Service (PHS) has undertaken a major effort to develop improved policies and procedures for dealing with misconduct in its research programs. Included in the definition of "misconduct" are the violation of Federal laws, regulations, or policies governing research or research training conducted, funded, or regulated by the Department of Health and Human Services; breaches of professional ethics that raise serious questions about an investigator''s or institution''s scientific or fiscal integrity; and serious failures to comply with other terms or conditions of an award. Recent incidents of falsification or misrepresentation of data and failure to comply with requirements for protection of human and animal subjects of research represent only a fraction of all research projects. However, they are troubling evidence that the traditional safeguards of science are not sufficient to prevent and detect willful wrongdoing. Research agencies, awardee institutions, and individual investigators have a collective responsibility to prevent misconduct in public research programs. The agencies and institutions, in turn, must deal promptly and equitably with allegations or evidence of misconduct. Individual research institutions and their professional organizations have developed policy statements affirming their responsibility for the integrity of the research enterprise and proposing specific procedures for dealing with incidents of misconduct. The National Institutes of Health currently serves as lead agency for a parallel PHS effort that includes a statement of general policies and principles, to be augmented by specific procedures for awarding agencies, regulatory agencies, and PHS intramural programs, as well as procedures for information sharing and joint investigations. 相似文献
62.
Endotracheal anaesthesia with the help of orotracheal intubation is 100 years old. In 1880, William Macewen was the first to describe and to perform that technique. In his paper entitled "clinical observations on the introduction of tracheal tubes by the mouth instead of performing tracheotomy or laryngotomy' he describes in addition two cases of endotracheal intubation lasting at least 36 h. He can, therefore, be said also to have performed the first long-time intubation. 相似文献
63.
Loss of heterozygosity for the short arm of chromosome 11 (11p15) in human milk epithelial cells immortalized by microinjection of SV40 DNA. 总被引:2,自引:0,他引:2
We have developed, by microinjection of SV40 DNA into human milk epithelial cells, a new mammary cell line, Hu-MI, which exhibits the phenotype of luminal cells or so-called "breast cancer precursor cells." This cell line retains the phenotype of primary cells as demonstrated by the expression of keratins 18 and 19 and of polymorphic epithelial mucins. However, the cells do not grow in agar after more than 80 passages, nor do they form tumors in nude mice. Established cells contain 2 copies of SV40 DNA integrated into the cellular genome and up to 14 copies of free SV40 DNA. A deletion of the short arm of chromosome 11 (11p15) including the c-Ha-ras and the beta-globin genes was found in the immortalized cells when the DNA from these cells was compared to the DNA from peripheral blood mononuclear cells obtained from the same donor. In addition, this cell line showed a good transfection efficiency for other DNA sequences using classical transfection and selection techniques with a neomycin resistance gene (pKOneo). Selective microinjection of DNA into tumor precursor cells may prove useful for the study of the molecular mechanisms involved in breast carcinogenesis. The possible significance of the loss of 11p13-15 in malignant progression of breast cancer is discussed. 相似文献
64.
Is verbal recognition memory really different in Huntington's and Alzheimer's disease. 总被引:1,自引:0,他引:1
Verbal recall and recognition were examined in Huntington's disease (HD) and Alzheimer's disease (AD) patients. Subgroups of HD and AD patients were matched for overall severity of dementia. Subjects were administered the Hopkins Verbal Learning Test, a list-learning task with three free-recall trials followed immediately by one yes/no recognition trial with semantically related and unrelated distractors. The matched AD and HD groups did not differ in the number of words recalled, although the HD patients showed slightly greater improvement over trials. Recognition performance was evaluated with measures of accuracy and response bias that are independent of each other. The matched groups did not differ in overall recognition accuracy, but the AD patients tended to have a more liberal ("yea-saying") response bias than did the HD patients. In addition, only the AD patients were differentially enticed to false-positive responding by semantically related distractors. The results suggest that the rule for making decisions when uncertain, rather than memory strength per se, distinguishes the recognition memory performance of AD and HD patients. 相似文献
65.
S. E. Starkstein J. Brandt F. Bylsma C. Peyser M. Folstein S. E. Folstein 《Neuroradiology》1992,34(6):487-489
Summary Magnetic resonance imaging and a comprehensive cognitive evaluation were carried out in a series of 29 patients with mild to moderate Huntington's disease (HD). A factor analysis of the neuropsychological test scores provided three factors: a memory/speed-of-processing factor, a frontal factor, and a response inhibition factor. The memory/speed factor correlated significantly with measures of caudate atrophy, frontal atrophy, and atrophy of the left (but not the right) sylvian cistern. There were no significant correlations between the frontal or response inhibition factors and measures of cortical or subcortical brain atrophy. Our findings confirm that subcortical atrophy is significantly correlated with specific cognitive deficits in HD, and demonstrate that cortical atrophy also has important association with the cognitive deficits of patients with HD. 相似文献
66.
Hodgkin's disease is highly curable today. Radiotherapy (RT) is the treatment of choice in the early stages. A mantle field is often used in the RT of Hodgkin's disease, and the technique and dosimetry are quite complex. We used computerized tomography (CT)-based dosimetry to determine doses delivered to different mediastinal nodes with the commonly used technique in Hodgkin's disease that was originally described by Kaplan. We used dose-volume histograms to determine doses to various groups of nodes in nine patients. Significant inhomogeneity (30%, 30%, 35%, 35%, 30%, 40%, 35%, 35%, and 30% in the nine patients) in dose distribution was found within the mediastinum. With the advent of 3-dimensional CT-based treatment planning, we are able to quantify such inhomogeneities. The question arises whether a homogeneous, lesser dose can achieve equal results. Average doses and "effective doses" were also calculated. The "effective doses" in eight patients (for a prescribed dose of 44 Gy) with a midline posterior spinal cord block added at 20 Gy were 37.3 Gy, 34.3 Gy, 36.0 Gy, 38.4 Gy, 35.8 Gy, 38.1 Gy, 36.7 Gy, and 36.7 Gy, respectively. A homogeneous dose equivalent to effective dose may achieve the same control as an inhomogeneous dose delivery. Prospective 3-D dosimetric studies are required to confirm this concept. 相似文献
67.
L J Brandt L Goldberg L H Bernstein G Greenberg 《The American journal of clinical nutrition》1979,32(9):1832-1836
An incubation system containing rat jejunoileum was used to determine whether analogues of cyanocabalamin (CNCbl) inhibited the in vitro absorption of CNCbl. The naturally occurring analogues "pseudo B12," "factor A," and the nonnaturally occurring analogue desdemethyl B12, were produced by guided biosynthesis with Propionibacterium arabinosum. Factor B was produced by acid cleavage of cyanocabalamin. Inhibition of Co57-CNBbl uptake was demonstrated for cold CNCbl and for desdemethyl B12, although statistical significance was achieved only for cold CNCbl at 40X and 100X the molar quantity of the radiolabeled CNCbl. However, a trend towards progressive inhibition of specific CNCbl binding was shown as increasing concentrations of CNCbl or desdemethyl B12 were used. No inhibition of specific CNCbl binding could be demonstrated for any of the naturally occurring cobamides tested. 相似文献
68.
Posttraumatic stress two years after the Oklahoma City bombing in youths geographically distant from the explosion 总被引:12,自引:0,他引:12
Pfefferbaum B Seale TW McDonald NB Brandt EN Rainwater SM Maynard BT Meierhoefer B Miller PD 《Psychiatry》2000,63(4):358-370
This article describes Posttraumatic Stress Disorder (PTSD) symptomatology in 69 sixth-grade youths who resided within 100 miles of Oklahoma City at the time of the 1995 bombing of the Alfred P. Murrah Federal Building. These youths neither had any direct physical exposure nor personally knew anyone killed or injured in the explosion. A survey conducted two years after the bombing assessed exposure, PTSD symptoms, and functioning. PTSD symptom frequency was measured with the Impact of Event Scale--Revised. Our BCD criteria for defining PTSD caseness was modeled after DSM-IV B, C, and D criteria requiring one reexperiencing, three avoidance/numbing, and two arousal symptoms for diagnosis. Those who met our BCD criteria had significantly higher PTSD symptom scores than those who did not. Both increased mean PTSD symptom score and meeting our caseness definition were associated with increased functioning difficulties. Media exposure and indirect interpersonal exposure (having a friend who knew someone killed or injured) were significant predictors of symptomatology. These findings suggest that children geographically distant from disaster who have not directly experienced an interpersonal loss report PTSD symptoms and functional impairment associated with increased media exposure and indirect loss. 相似文献
69.
The determination of prostate-specific antigen is credited with dramatic advances in the early detection of men with prostatic carcinoma. This report summarizes the history of biochemical research and current status of prostate-specific antigen in tumor diagnostics. 相似文献
70.
Dietary carotenoids and risk of lung cancer in a pooled analysis of seven cohort studies. 总被引:5,自引:0,他引:5
Satu M?nnist? Stephanie A Smith-Warner Donna Spiegelman Demetrius Albanes Kristin Anderson Piet A van den Brandt James R Cerhan Graham Colditz Diane Feskanich Jo L Freudenheim Edward Giovannucci R Alexandra Goldbohm Saxon Graham Anthony B Miller Thomas E Rohan Jarmo Virtamo Walter C Willett David J Hunter 《Cancer epidemiology, biomarkers & prevention》2004,13(1):40-48
Intervention trials with supplemental beta-carotene have observed either no effect or a harmful effect on lung cancer risk. Because food composition databases for specific carotenoids have only become available recently, epidemiological evidence relating usual dietary levels of these carotenoids with lung cancer risk is limited. We analyzed the association between lung cancer risk and intakes of specific carotenoids using the primary data from seven cohort studies in North America and Europe. Carotenoid intakes were estimated from dietary questionnaires administered at baseline in each study. We calculated study-specific multivariate relative risks (RRs) and combined these using a random-effects model. The multivariate models included smoking history and other potential risk factors. During follow-up of up to 7-16 years across studies, 3,155 incident lung cancer cases were diagnosed among 399,765 participants. beta-Carotene intake was not associated with lung cancer risk (pooled multivariate RR = 0.98; 95% confidence interval, 0.87-1.11; highest versus lowest quintile). The RRs for alpha-carotene, lutein/zeaxanthin, and lycopene were also close to unity. beta-Cryptoxanthin intake was inversely associated with lung cancer risk (RR = 0.76; 95% confidence interval, 0.67-0.86; highest versus lowest quintile). These results did not change after adjustment for intakes of vitamin C (with or without supplements), folate (with or without supplements), and other carotenoids and multivitamin use. The associations generally were similar among never, past, or current smokers and by histological type. Although smoking is the strongest risk factor for lung cancer, greater intake of foods high in beta-cryptoxanthin, such as citrus fruit, may modestly lower the risk. 相似文献