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91.
Modulation of activity in medial frontal and motor cortices during error observation 总被引:3,自引:0,他引:3
We used measures of the human event-related brain potential (ERP) to investigate the neural mechanisms underlying error processing during action observation. Participants took part in two conditions, a task execution condition and a task observation condition. We found that activity in both the medial frontal cortex and the motor cortices, as measured via the error-related negativity and the lateralized readiness potential, respectively, was modulated by the correctness of observed behavior. These data suggest that similar neural mechanisms are involved in monitoring one's own actions and the actions of others. 相似文献
92.
For some time, clinical reports have described impairment of affective and cognitive functions in iron deficient persons. Recent studies suggest that both brain biochemistry and cognitive performance capacity may be disrupted by inadequate intake of dietary iron, but the relationship of the possible neurophysiological effects to psychological ones is unclear. To examine the relationship of iron status to simultaneous measures of cortical activation and cognitive performance, 8 channels of electroencephalographic (EEG) data were recorded during a resting period and during the performance of several cognitive tasks in two groups of men. The EEG data were spectrally analyzed, and measures of total power and frequency of peak power in each of several bands of the power spectrum for each channel were used as predictors in multiple regression analyses with serum iron and serum ferritin as alternative criteria. Measures of power in the delta frequency in the resting period appeared relevant to iron status in both groups, perhaps indicating alertness or arousal level. Consistently in these regressions, the asymmetry of the EEG appeared relevant to iron and ferritin. These findings suggest that the combination of EEG and performance measures may help characterize the neuropsychological effects of trace element nutrition. 相似文献
93.
Kim Alexis H.; Khanna Amit; Aten Raymond F.; Olive David L.; Behrman Harold R. 《Molecular human reproduction》1996,2(8):549-554
The infiltration of leukocytes is a characteristic feature ofluteolysis in humans. Leukocytes are known to generate physiologicalinducers of cell stress such as cytokines which have been implicatedas mediators of functional luteal regression. In cells exposedto stress, a response characterized by an increase in heat shockprotein (HSP) synthesis occurs. Recently, the induction of HSP-70in rat luteal cells has been shown to inhibit luteinizing hormone(LH) and cAMP-sensitive progesterone production, possibly byinterfering with the translocation of cholesterol to the mitochondrialcytochrome P450SCC. We therefore investigated whether HSP-70is induced in human granulosa-luteal cells and its relationshipto steroidogenesis. [35S]Methionine labelling showed an increasein a 70 kDa protein after heat treatment which was demonstratedto be HSP-70 by Western analysis using monoclonal antibodiesagainst the constitutive and inducible forms of HSP-70. Inductionof HSP-70 in human granulosa-luteal cells was also seen withinterferon (IFN) (10 ng/ml), tumour necrosis factor (TNF)- 相似文献
94.
Chang Richard L.; Huang Mou-Tuan; Wood Alexander W.; Wong Ching-Quo; Newmark Harold L.; Yagi Haruhiko; Sayer Jane M.; Jerina Donald M.; Conney Allan H. 《Carcinogenesis》1985,6(8):1127-1133
Ellagic acid, quercetin and robinetin were tested for theirability to antagonize the tumor-initiating activity of benzo[a]pyrene(B[a]P) and (±)-7ß, 8-dihydroxy-9, 10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene(B[a]P 7,8-diol-9,10-epoxide-2), the ultimate carcinogenic metaboliteof benzo[a]pyrene. Ellagic acid, robinetin or quercetin (2500nmol) had no tumor-initiating activity on mouse skin, but thetopical application of 2500 nmol of ellagic acid 5 min beforea tumor-initiating dose of 200 nmol of B[a]P 7,8-diol-9,10-epoxide-2caused a 5966% inhibition in the number of skin tumorsper mouse that were observed after 1520 weeks of promotionwith 12-O-tetradecanoylphorbol-13-acetate. Similar treatmentwith 2500 nmol of robinetin or quercetin caused a statisticallyinsignificant 1624% inhibition in the tumor-initiatingactivity of 200 nmol of B[a]P 7,8-diol-9,10-epoxide-2 applied5 min later. Treatment of mice with 2500 nmol of ellagic acid5 min before the application of 50 nmol of B[a]P inhibited themean number of skin tumors per mouse by 2833% after 1520weeks of promotion, but these decreases were not statisticallysignificant. Robinetin and quercetin had little or no effecton the tumor-initiating activity of B[a]P on mouse skin. Treatmentof preweanling mice with 1/7, 2/7 and 4/7 of the total doseof ellagic acid (300 nmol), robinetin (1400 nmol), myricetin(1400 nmol) or quercetin (1400 nmol) i.p. on their first, eighthand fifteenth day of life, respectively, did not cause the formationof tumors in animals that were killed 911 months later.Similar treatment of preweanling mice with the above doses ofthe phenolic compounds 10 min before the i.p. injection of atotal dose of 30 nmol of B[a]P 7,8-diol-9,10-epoxide-2 duringthe animal's first 15 days of life caused a 4475% inhibitionin the number of diol-epoxide-induced pulmonary tumors per mouse.Similar treatment with these plant phenols had little or noeffect on B[a]P-induced pulmonary tumors. 相似文献
95.
Elliot Fielstein Michael S. Klein Mariellen Fischer Cheryl Hanan Penelope Koburger Mary Jean Schneider Harold Leitenberg 《Cognitive therapy and research》1985,9(4):381-398
In a comparison of causal attributions following success and failure in hypothetical social, athletic, and academic situations, high self-esteem grade school children were more likely than low self-esteem children to attribute their success to ability and their failure to either lack of effort or bad luck. Low self-esteem children, on the other hand, attributed their success more often than high self-esteem children to good luck (and in social situations to effort and task ease as well) and their failure to lack of ability. Whereas prior studies that focused only on the internal-external dimension found that low and high self-esteem children differed in their attributional style to success but not to failure, the present study found that when distinctions between behavioral and characterological attributions (stability and globality dimensions) were included, the two groups differed significantly in response to both success and failure. Although perhaps not generalizable beyond the present attribution measure, the most pronounced attribution differences between low and high self-esteem children were observed in the social domain, the least in the academic domain, with athletics falling in between. Finally, it was found that sex and age (within the limited fourth- to sixth-grade range examined in the present study) did not alter the overriding difference in attributional style between low and high self-esteem children.This study is based on a doctoral dissertation submitted by the first author under the supervision of the last author in partial fulfillment of the requirements for the Ph.D. degree at the University of Vermont. 相似文献
96.
Kucharczyk W; Brant-Zawadzki M; Lemme-Plaghos L; Uske A; Kjos B; Feinberg DA; Norman D 《Radiology》1985,157(1):95-101
In multiple spin-echo image sequences of blood flow, the "even-echo" phenomenon produces an absolute increase in signal magnitude from first- to second-echo images of normal vessels harboring slow flow. Distinguishing this from the apparent relatively high signal intensity seen on second-echo images in pathologic foci of stationary tissue is important to the diagnostician. Selected case material containing two tissue types was reviewed retrospectively: tissues known to harbor slow flow, such as normal veins and venous sinuses and vascular malformations, and tissues that have long transverse (T2) relaxation times and appear as intense structures on second-echo images, such as neoplasms, infarcts, and regions of demyelination. Calculations of T2 parameters were made by computer for defined regions of interest. T2 images were also generated. Visual inspection of the acquired images did not reliably distinguish increased intensity due to even-echo rephasing from the relative changes between adjacent tissues seen on second-echo images. More definitive differentiation of the even-echo phenomenon was provided by calculated values of T2 and computer-synthesized T2 images representing acquired intensity data of two-echo sequences. The synthesized images were especially useful when stationary tissue with lengthened T2 values was adjacent to or in proximity to vessels or vascular lesions. A five spin-echo image sequence was valuable for separating slow flow from stationary tissue by a technique of synthesizing T2-difference images using three consecutive echoes. 相似文献
97.
The differential diagnosis and treatment of pseudodementia, dementia, and depressive illness are receiving increased attention. The literature on this subject is reviewed, and four "ideal types" of patients spanning the spectrum of these illnesses are proposed for use when their distinction or association is at issue. Attempts by investigators to distinguish those groups are summarized, ad the importance of diagnostic clarity and patient selection for future research is emphasized. 相似文献
98.
Feinberg Mark E. Fang Shichen Fosco Gregory M. Sloan Carlie J. Mogle Jacqueline Spoth Richard L. 《Prevention science》2022,23(7):1264-1275
Prevention Science - We examined whether participation in adolescent substance use prevention programming can enhance long-term resilience into adulthood such that individuals were better able to... 相似文献
99.
100.
Matthew S. Austin Blair S. Ashley Nicholas A. Bedard Hari P. Bezwada Charles P. Hannon Yale A. Fillingham Yogesh V. Kolwadkar Harold W. Rees Matthew J. Grosso Erik N. Zeegen 《The Journal of arthroplasty》2021,36(8):2665-2673.e8
BackgroundThe prevalence of total joint arthroplasty (TJA) in the United States has drawn the attention of health care stakeholders. The payers have also used a variety of strategies to regulate the medical necessity of these procedures. The purpose of this study was to examine the level of evidence of the coverage policies being used by commercial payers in the United States.MethodsThe references of the coverage policies of four commercial insurance companies were reviewed for type of document, level of evidence, applicability to a TJA population, and success of nonoperative treatment in patients with severe degenerative joint disease.Results282 documents were reviewed. 45.8% were primary journal articles, 14.2% were level I or II, 41.2% were applicable to patients who were candidates for TJA, and 9.9% discussed the success of nonoperative treatment in patients who would be candidates for TJA.ConclusionMost of the references cited by commercial payers are of a lower level of scientific evidence and not applicable to patients considered to be candidates for TJA. This is relatively uniform across the reviewed payers. The dearth of high-quality literature cited by commercial payers reflects the lack of evidence and difficulty in conducting high level studies on the outcomes of nonoperative versus operative treatment for patients with severe, symptomatic osteoarthritis. Patients, surgeons, and payers would all benefit from such studies and we encourage professional societies to strive toward that end through multicenter collaboration. 相似文献