全文获取类型
收费全文 | 9439篇 |
免费 | 708篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 122篇 |
儿科学 | 240篇 |
妇产科学 | 245篇 |
基础医学 | 1516篇 |
口腔科学 | 162篇 |
临床医学 | 816篇 |
内科学 | 2109篇 |
皮肤病学 | 127篇 |
神经病学 | 893篇 |
特种医学 | 365篇 |
外科学 | 1264篇 |
综合类 | 117篇 |
现状与发展 | 1篇 |
一般理论 | 15篇 |
预防医学 | 771篇 |
眼科学 | 232篇 |
药学 | 540篇 |
中国医学 | 11篇 |
肿瘤学 | 634篇 |
出版年
2023年 | 101篇 |
2022年 | 188篇 |
2021年 | 313篇 |
2020年 | 179篇 |
2019年 | 316篇 |
2018年 | 325篇 |
2017年 | 198篇 |
2016年 | 218篇 |
2015年 | 273篇 |
2014年 | 328篇 |
2013年 | 474篇 |
2012年 | 603篇 |
2011年 | 659篇 |
2010年 | 320篇 |
2009年 | 337篇 |
2008年 | 511篇 |
2007年 | 562篇 |
2006年 | 479篇 |
2005年 | 487篇 |
2004年 | 516篇 |
2003年 | 466篇 |
2002年 | 440篇 |
2001年 | 127篇 |
2000年 | 92篇 |
1999年 | 105篇 |
1998年 | 90篇 |
1997年 | 80篇 |
1996年 | 67篇 |
1995年 | 69篇 |
1994年 | 57篇 |
1993年 | 55篇 |
1992年 | 57篇 |
1991年 | 54篇 |
1990年 | 48篇 |
1989年 | 61篇 |
1988年 | 50篇 |
1987年 | 57篇 |
1986年 | 36篇 |
1985年 | 39篇 |
1984年 | 42篇 |
1983年 | 40篇 |
1982年 | 38篇 |
1980年 | 33篇 |
1979年 | 33篇 |
1978年 | 31篇 |
1976年 | 32篇 |
1974年 | 35篇 |
1973年 | 44篇 |
1971年 | 34篇 |
1970年 | 32篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Emotion-modulated startle is a robust phenomenon that has been demonstrated in a wide range of experimental situations. Similarly, heart rate variability (HRV) has been associated with a diverse range of processes including affective and attentional regulation. The present study sought to examine the relationship between these two important measures of affective behavior. Ninety female participants viewed pleasant, neutral, and unpleasant pictures while exposed to acoustic startle stimuli. The eyeblink startle was recorded both during the affective foregrounds and during intertrial intervals. HRV was assessed during a resting baseline and relationships between HRV and startle magnitudes examined. Results indicated that resting HRV was inversely related to startle magnitude during both intertrial intervals and affective foregrounds. In addition, the participants with the highest HRV showed the most differentiated emotion-modulated startle effects, whereas those with the lowest HRV, compared to those with the highest HRV, showed significantly potentiated startle to neutral foregrounds and marginally potentiated startle to pleasant foregrounds. The findings are consistent with models that posit that prefrontal cortical activity modulates subcortical motivation circuits. These results have important implications for the use of startle probe methodology and for HRV in the study of emotional regulation and dysregulation. 相似文献
52.
53.
Volker Schmidt Susanne Schneider Julian Schlömer Maria-Elisabeth Krautwald-Junghanns Elvira Richter 《Avian pathology》2008,37(6):589-592
The present report describes a case of Mycobacterium tuberculosis infection in an African Grey parrot (Psittacus erithacus erithacus) kept as a pet bird. Diagnosis was confirmed by microbiologic and pathologic results, and indicated a human–avian transmission. Clinical signs included sublingual nodules resulting in anorexia and signs of osteolysis in the long bones. Proliferation consisted of several nodules with small greenish-caseous foci in cross-section and revealed a severe granulomatous inflammation without intralesional acid-fast rods. M. tuberculosis was cultured from a pooled sample of sublingual and liver nodules, and was confirmed via polymerase chain reaction. Transmission between men and parrot was proved by spoligotyping pattern analysis. The absence of facial skin lesions and acid-fast rods within the tubercles is contrary to previous publications of tuberculosis in birds. This disease in a common pet bird species is of zoonotic importance, and those parrots with close contact to owners suffering from tuberculosis may serve as a potential reservoir for human infection. 相似文献
54.
Reading Julian P.; Huffman John L.; Wu Joy C.; Palmer Frances T.; Harton Gary L.; Sisson Michael E.; Keyvanfar Keyvan; Gresinger Thomas H.; Cochrane William J.; Fallon Lee A.; Menapace-Drew Gianna F.; Cummings Emilie A.; Jones Shirley L.; Black Susan H.; Schulman Joseph D.; Levinson Gene 《Molecular human reproduction》1995,1(7):362-367
The discovery of nucleated erythrocytes in maternal circulationprovides a potential source for non-invasive prenatal diagnosis.We have evaluated the use of a three-stage procedure to determinethe number of cells that are of fetal rather than maternal origin.First, monoclonal antibodies specific for CD45 and CD14 wereused in conjunction with a magnetic (MACS) column to depleteunwanted leukocytes from maternal blood. This was followed bya positive MACS enrichment for nucleated erythrocytes, usingan anti-CD71 (transferrin receptor) monoclonal antibody. Todiscriminate between fetal nucleated erythrocytes and thoseof maternal origin, enriched fractions were simultaneously stainedwith an anti-fetal haemoglobin (HbF) antibody and hybridizedwith probes specific for X and Y chromosomes. Samples were thensubjected to blind analysis along with negative control samplesfrom non-pregnant volunteers. Using this dual analysis, we wereable to determine that less than one nucleated erythrocyte perml of maternal blood was of fetal origin. Small numbers of thesefetal cells were found in 87.5% of pregnancies, ranging from6 to 35 weeks gestational age. Comparison of HbF and X/Y probedata also suggests that the fetal cells are less suitable forfluorescence in-situ hybridization (FISH) analysis than similarpreparations from other sources. cell separation methods/fluorescence in-situ hybridization/hereditary diseases/polymerase chain reaction/pregnancy 相似文献
55.
Sarah L. Rowland-Jones Stephen H. Powis Julian Sutton Ian Mockridge Frances M. Gotch Nick Murray Ann B. Hill William M. Rosenberg John Trowsdale Andrew J. McMichael 《European journal of immunology》1993,23(8):1999-2004
In previous studies of antigen presentation through HLA-B27, we identified a healthy person whose lymphoblastoid cells do not present three B27-restricted viral epitopes to specific cytotoxic T lymphocytes (CTL), despite adequate cell surface expression of HLA-B2702 of normal sequence. Similar findings were observed in all members of his family sharing the HLA-A3-B2702 haplotype. The original donor, NW, carries HLA-B8 on his other class I haplotype, which his daughter, HW, has inherited. We now report a failure to present an HLA-B8-restricted epitope from influenza nucleoprotein following viral infection of NW cells, although exogenous added peptide is still presented normally. However, cells from HW, which do not carry the A3-B2702 haplotype, present the expected epitope after viral infection. Another B8-restricted epitope, from human immunodeficiency virus-gag, is presented equally well by both cell lines when infected with gag-vaccinia. This antigen processing phenotype does not correlate with any of the known human TAP-1 and TAP-2 polymorphisms. 相似文献
56.
Peter E. R. Tatham Michael R. Duchen Julian Millar 《Pflügers Archiv : European journal of physiology》1991,419(3-4):409-414
We have used fast differential ramp voltammetry with carbon-fibre electrodes to monitor exocytotic secretion in single rat mast cells. The oxidation peak and other aspects of the electrochemical profile of the substance released were similar to those of 5-hydroxytryptamine (5-HT) and the signals were increased by preloading the secretory granules with exogenous 5-HT. Metabolic blockade inhibited both visible degranulation and the electrochemical signal. For comparison, quinacrine, which is fluorescent and accumulates in secretory vesicles, was used as an alternative means of detecting secretion in single cells. The amplitude of the electrochemical signals observed during degranulation correlated well with the loss of quinacrine fluorescence. Both methods were used to record successive rounds of secretion in single mast cells in response to repeated applications of compound 48/80. 相似文献
57.
Simon Sanderson Ron Zimmern Mark Kroese Julian Higgins Christine Patch Jon Emery 《Genetics in medicine》2005,7(7):495-500
Advances in genetic technology are increasing the availability of genetic tests, not only for rare single gene disorders, but also for common diseases such as breast and colo-rectal cancer. Before there can be widespread uptake of these tests, they must be evaluated to confirm the benefits of their use. But how should genetic tests be evaluated, given the speed at which new tests are emerging? One highly influential approach is the analytic validity, clinical validity, clinical utility and ethical, legal and social issues (ACCE) framework, which has provided a benchmark for the evaluation of genetic tests. The approach has been adopted and adapted by the United Kingdom Genetic Testing Network, with the help of the Public Health Genetics Unit in Cambridge, to evaluate new genetic tests for use in the National Health Service. We discuss a number of conceptual, methodological, and practical issues concerning the evaluation of genetic tests, based on lessons learned from applying the ACCE framework and from the UK experience, and make a number of recommendations to further strengthen the evaluation of genetic tests. 相似文献
58.
Julian F Thayer Martica Hall John J Sollers Joachim E Fischer 《International journal of psychophysiology》2006,59(3):244-250
Alcoholism and heavy drinking are associated with a number of physiological, behavioral, affective, and cognitive problems. One such problem involves dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, with alcoholics showing higher basal cortisol levels and reduced inhibitory feedback control. In addition, alcohol consumption is associated with decreased heart rate variability (HRV). In the present study we examined the relationships among alcohol consumption, cortisol excretion, and HRV in 542 apparently healthy men. Men in the top tertile of self-reported alcohol consumption had higher cortisol levels and lower HRV compared to men in the lower two tertiles of alcohol consumption. In addition, the inverse relationship between cortisol and HRV was greatly attenuated in the heavy drinking group even after accounting for a number of potential confounding factors. These results support prior research on the HPA axis dysregulation in alcoholics and suggest impaired inhibitory control of the HPA axis in heavy drinkers. The findings are consistent with the neurovisceral integration model, which links central and peripheral processes, and may provide a comprehensive framework for the future investigation of the complex mix of physiological, behavioral, affective, and cognitive factors which comprise the heavy drinking phenotype. 相似文献
59.
Welmoed van Loon Heike Rssig Susen Burock Jrg Hofmann Julian Bernhard Elisabeth Linzbach Domenika Pettenkofer Christian Schnfeld Maximilian Gertler Joachim Seybold Tobias Kurth Frank P. Mockenhaupt 《Emerging infectious diseases》2021,27(7):1931
Within 5 weeks in 2021, B.1.1.7 became the dominant severe acute respiratory syndrome coronavirus 2 lineage at an outpatient testing site in Berlin, Germany. Compared with outpatients with wild-type virus infection, patients with B.1.1.7 had similar cycle threshold values, more frequent sore throat and travel history, and less frequent anosmia/ageusia. 相似文献
60.
Julian Marcon Matthias Trottmann Severin Rodler Armin J. Becker Christian G. Stief Ricarda M. Bauer Jozefina Casuscelli 《Andrologia》2021,53(1):e13881
We longitudinally assessed erectile function as well as the willingness to use pro-erectile treatment in a cohort on AAT for advanced RCC. Thirty-seven patients with advanced RCC completed the five-item version of the International Index of Erectile Function (IIEF-5) and other interview items before (T0) and 12 weeks into therapy (T12) with AAT. Patients were further asked if they were willing to use and pay out-of-pocket for on-demand treatment with phosphodiesterase-5-inhibitors (PDE-5i). Statistical analysis was performed using nonparametric hypothesis testing. The IIEF-5 score at T12 was significantly decreased compared with T0 (p < .001). Subjective patient satisfaction regarding their sexual lives was associated with higher IIEF-5 scores at both time points (p = .006 and p = .03, respectively). At T12, subjective sexual contentment showed a nonsignificant trend towards decline (p = .074). Patients who opted for medical treatment of ED showed significantly better IIEF-5 scores at both time points compared with the rest of the cohort (p < .001 and p = .005, respectively). In summary, AAT seems to have a negative effect on erectile function in RCC patients, however, the role of psychosocial issues warrants further elucidation. Affected patients may benefit from a proactive approach promoting medical treatment of erectile dysfunction during AAT. 相似文献