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排序方式: 共有1714条查询结果,搜索用时 15 毫秒
51.
Marit Kramski Gregor F. Lichtfuss Marjon Navis Gamze Isitman Leia Wren Grant Rawlin Rob J. Center Anthony Jaworowski Stephen J. Kent Damian F. J. Purcell 《European journal of immunology》2012,42(10):2771-2781
Antibodies with antibody‐dependent cellular cytotoxicity (ADCC) activity play an important role in protection against HIV‐1 infection, but generating sufficient amounts of antibodies to study their protective efficacy is difficult. HIV‐specific IgG can be easily and inexpensively produced in large quantities using bovine colostrum. We previously vaccinated cows with HIV‐1 envelope gp140 and elicited high titers of anti‐gp140‐binding IgG in colostrum. In the present study, we determined whether bovine antibodies would also demonstrate specific cytotoxic activity. We found that bovine IgG bind to Fcγ‐receptors (FcγRs) on human neutrophils, monocytes, and NK cells in a dose‐dependent manner. Antibody‐dependent killing was observed in the presence of anti‐HIV‐1 colostrum IgG but not nonimmune colostrum IgG. Killing was dependent on Fc and FcγR interaction since ADDC activity was not seen with F(ab’)2 fragments. ADCC activity was primarily mediated by CD14+ monocytes with FcγRIIa (CD32a) as the major receptor responsible for monocyte‐mediated ADCC in response to bovine IgG. In conclusion, we demonstrate that bovine anti‐HIV colostrum IgG have robust HIV‐1‐specific ADCC activity and therefore offer a useful source of antibodies able to provide a rapid and potent response against HIV‐1 infection. This could assist the development of novel Ab‐mediated approaches for prevention of HIV‐1 transmission. 相似文献
52.
María Jesús Fernández Aceñero MD PhD Cristina Díaz del Arco CDdA MD Carme Dinarés CD MD PhD Tania Labiano TL MD Eva Tejerina ET MD PhD Mª José Bernabé MJ B MD Elena Forcen EF MD Melchor Saiz-Pardo MSP MD Pablo Pérez PP MD Maria D. Lozano MDL MD PhD 《Diagnostic cytopathology》2023,51(1):26-35
Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples. 相似文献
53.
Barnett R Maruff P Purcell R Wainwright K Kyrios M Brewer W Pantelis C 《Psychological medicine》1999,29(5):1227-1233
BACKGROUND: Olfactory identification ability has been associated with processing in the orbitofrontal cortex (OFC), an area that has been implicated in the pathophysiology of obsessive-compulsive disorder (OCD). Although olfactory sensitivity is normal in patients with OCD, no study has investigated olfactory identification in this disorder. METHODS: A group of 20 subjects with OCD and 23 age- and education-matched controls performed a standardized test of olfactory identification. They also performed computerized tests of spatial memory span, spatial working memory and spatial recognition memory that have been shown previously to be sensitive to cognitive deficits in patients with OCD. RESULTS: Performance on the olfactory identification task, spatial recognition task and spatial span task was significantly worse in the OCD group than controls. CONCLUSIONS: While impairment in spatial cognition is consistent with previous studies of OCD, its significance for brain-behaviour models of OCD is unclear. However, the finding of abnormal olfactory identification in patients with OCD is consistent with the hypothesis that there is a disruption to processing at the level of the OFC in the disorder. 相似文献
54.
Metsch LR Pereyra M Purcell DW Latkin CA Malow R Gómez CA Latka MH;for the INSPIRE Study Team 《Journal of acquired immune deficiency syndromes (1999)》2007,46(Z2):S72-S79
Among HIV-positive injection drug users (IDUs), we examined the correlates of lending needles/syringes with HIV-negative and unknown status injection partners. HIV-positive IDUs (N=738) from 4 cities in the United States who reported injection drug use with other IDUs in the past 3 months participated in an audio computer-assisted self-administered interview. Eighteen percent of study participants self-reported having lent their needles to HIV-negative or unknown status injection partners. Multivariate analyses showed that 6 variables were significantly associated with this high-risk injecting practice. Older IDUs, high school graduates, and those reporting more supportive peer norms for safer drug use were less likely to lend needles/syringes. Admission to a hospital for drug treatment in the past 6 months, having injected with >1 person in the past 3 months, and having more psychiatric symptoms were all associated with more risk. These findings underscore the need for a continued prevention focus on HIV-positive IDUs that recognizes the combination of drug use, mental health factors, and social factors that might affect this high-risk injecting practice, which could be associated with HIV and hepatitis C transmission. 相似文献
55.
Selection of cases with additional affected relatives has been shown to increase the power of the case-control association
design. We investigated whether this strategy can also improve the power of family-based association studies that use the
transmission disequilibrium test (TDT), while accounting for the effects of residual polygenic and environmental factors on
disease liability. Ascertainment of parent-offspring trios conditional on the proband having affected first-degree relatives
almost always reduced the power of the TDT. For many disease models, this reduction was quite considerable. In contrast, for
the same sample size, designs that analyzed more than one affected offspring per family often improved power when compared
to the standard parent-offspring trio design. Together, our results suggest that (1) residual polygenic and environmental
influences should be considered when estimating the power of the TDT for studies that ascertain families with multiple affected
relatives; (2) if trios are selected conditional on having additional affected offspring, then it is important to genotype
and include in the analysis the additional siblings; (3) the ascertainment strategy should be considered when interpreting
results from TDT analyses. Our analytic approach to estimate the asymptotic power of the TDT is implemented online at http://pngu.mgh.harvard.edu/∼purcell/gpc/.
Edited by David Allison 相似文献
56.
57.
58.
Purcell H 《The Practitioner》2000,244(1611):502, 505-506, 508
59.
J. Steuten K. Winkel T. Carroll N.A. Williamson V. Ignjatovic K. Fung A.W. Purcell B.G. Fry 《Toxicon》2007,50(8):1041-1052
The Snake Venom Detection Kit (SVDK) is of major medical importance in Australia, yet it has never been rigorously characterised in terms of its sensitivity and specificity, especially when it comes to reports of false-negative and false-positive results. This study investigates reactions and cross-reactions of five venoms the SVDK is directed against and a number of purified toxins. Snakes showing the closest evolutionary relationships demonstrated the lowest level of cross-reactivity between groups. This was, instead, far more evident between snakes that are extraordinarily evolutionary separated. These snakes: Pseudechis australis, Acanthophis antarcticus and Notechis scutatus, in fact displayed more false-positive results. Examination of individual toxin groups showed that phospholipase A2s (PLA2s) tends to react strongly and display considerable cross-reactivity across groups while the three-finger toxins (3FTx) reacted poorly in all but the Acanthophis well. The hook effect was evident for all venoms, particularly Oxyuranus scutellatus. The results of this study show considerable variation in toxin detection, with implications in further development of venom detection, both in Australia and other countries. 相似文献
60.