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排序方式: 共有732条查询结果,搜索用时 0 毫秒
721.
Timothy M. Stearns Clinton L. Cario Holly S. Savage John P. Sundberg Beverly Paigen Annerose Berndt 《Experimental and molecular pathology》2012
Lung cancer is the most common cause of cancer-related deaths in both men and women, and effective preventatives are rare due to the difficulty of early detection. Specific gene expression signatures have been identified in individuals that already developed lung cancer. To identify if gene expression differences could be detected in individuals before the onset of the disease, we obtained lung tissues for microarray analysis from young, healthy mice of 9 inbred strains with known differences in their susceptibility to spontaneous pulmonary adenomas when aged. We found that the most common differentially expressed genes among all possible 36 strain comparisons showed significant associations with cancer- and inflammation-related processes. Significant expression differences between susceptible and resistant strains were detected for Aldh3a1, Cxcr1 and 7, Dpt, and Nptx1—genes with known cancer-related functions, and Cd209, Cxcr1 and 7, and Plag2g1b—genes with known inflammatory-related functions. Whereas Aldh3a1, Cd209, Dpt, and Pla2g1b had increased expression, Cxcr1 and 7, and Nptx1 had decreased expression in strains susceptible to pulmonary adenomas. Thus, our study shows that expression differences between susceptible and resistant strains can be detected in young and healthy mice without manifestation of pulmonary adenomas and, thus, may provide an opportunity of early detection. Finally, the identified genes have previously been reported for human non-small cell lung cancer suggesting that molecular pathways may be shared between these two cancer types. 相似文献
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Wøjdemann KR Larsen SO Shalmi AC Sundberg K Tabor A Christiansen M 《Prenatal diagnosis》2006,26(3):218-220
OBJECTIVES: To establish the distribution of serological and ultrasound first-trimester Down syndrome markers in twins and identify correlations of significance for risk calculation. METHODS: Nuchal translucency (NT), PAPP-A and betahCG data were extracted from 181 twin pregnancies (31 mono- and 150 dichorionic) with a normal outcome. All pregnancies were consecutively and prospectively included and examined in the Copenhagen First-Trimester Study. The variance of the sum and the difference of log MoM NT values in twin pairs was used to calculate the correlation. RESULTS: The serological markers did not correlate and were nearly twice the value seen in singleton pregnancies with a median PAPP-A MoM of 2.14 and a median free betahCG MoM of 2.06. Chorionicity was not found to influence the level of biochemical markers. In all twin pairs (r = 0.343, p < 0.001, F-test), as well as mono- (r = 0.404, p = 0.011, F-test) and dichorionic twins (r = 0.316, p < 0.001, F-test) there was a significant correlation between log MoM NT in each pair. CONCLUSION: As the NT values of fetuses in subsequent pregnancies from the same woman do not correlate, the correlation between NTs in twins reflects that the NT is influenced by placental and maternal factors specific for the particular pregnancy, for example, nutrient supply or vascularisation. The correlation may be useful to improve the precision of the prenatal risk assessment for Down syndrome in first-trimester twin pregnancies. The serological markers were elevated in the examined twins as previously described. 相似文献
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Research on the vocal expression of emotion has long since used a “fishing expedition” approach to find acoustic markers for emotion categories and dimensions. Although partially successful, the underlying mechanisms have not yet been elucidated. To illustrate that this research can profit from considering the underlying voice production mechanism, we specifically analyzed short affect bursts (sustained/a/vowels produced by 10 professional actors for five emotions) according to physiological variations in phonation (using acoustic parameters derived from the acoustic signal and the inverse filter estimated voice source waveform). Results show significant emotion main effects for 11 of 12 parameters. Subsequent principal components analysis revealed three components that explain acoustic variations due to emotion, including “tension,” “perturbation,” and “voicing frequency.” These results suggest that future work may benefit from theory-guided development of parameters to assess differences in physiological voice production mechanisms in the vocal expression of different emotions. 相似文献
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Haukebø K Skaret E Ost LG Raadal M Berg E Sundberg H Kvale G 《Journal of behavior therapy and experimental psychiatry》2008,39(3):381-390
Forty participants fulfilling the DSM-IV criteria for dental phobia were randomly assigned to a waitlist group, one-session or five-session exposure treatment. Assessment occurred pre-, post-waitlist/treatment, and after 1 year. Mean avoidance of dental care before treatment was 11.4 years. A total of 77% sought dental care in the follow-up year. Both treatments were equally effective at reducing avoidance behavior and changing cognitions during the feared situation. Post-treatment, the five-session group scored lower on the dental anxiety scales, but at follow-up, both groups reported the same level of dental anxiety. Conclusion: Both treatment conditions enable a return to ordinary dental treatment. 相似文献
728.
Genetically null mice reveal a central role for epidermal growth factor receptor in the differentiation of the hair follicle and normal hair development. 总被引:9,自引:2,他引:9 下载免费PDF全文
L. A. Hansen N. Alexander M. E. Hogan J. P. Sundberg A. Dlugosz D. W. Threadgill T. Magnuson S. H. Yuspa 《The American journal of pathology》1997,150(6):1959-1975
Mice harboring a targeted disruption of the epidermal growth factor receptor (EGFR) allele exhibit a severely disorganized hair follicle phenotype, fuzzy coat, and systemic disease resulting in death before 3 weeks. This skin phenotype was reproduced in whole skin grafts and in grafts of EGFR null hair follicle buds onto nude mice, providing a model to evaluate the natural evolution of skin lacking the EGFR. Hair follicles in grafts of null skin did not progress from anagen to telogen and scanning electron micrografts revealed wavy, flattened hair fibers with cuticular abnormalities. Many of the EGFR null hair follicles in the grafted skin were consumed by an inflammatory reaction resulting in complete hair loss in 67% of the grafts by 10 weeks. Localization of follicular differentiation markers including keratin 6, transglutaminase, and the hair keratins mHa2 and hacl-1 revealed a pattern of premature differentiation within the null hair follicles. In intact EGFR null mice, proliferation in the interfollicular epidermis, but not hair follicles, was greatly decreased in the absence of EGFR. In contrast, grafting of EGFR null skin resulted in a hyperplastic response in the epidermis that did not resolve even after 10 weeks, although the wound-induced hyperplasia in EGFR wild-type grafts had resolved within 3 to 4 weeks. Thus, epithelial expression of the EGFR has complex functions in the skin. It is important in delaying follicular differentiation, may serve to protect the hair follicle from immunological reactions, and modifies both normal and wound-induced epidermal proliferation but seems dispensable for follicular proliferation. 相似文献
729.
Krebs LT Xue Y Norton CR Shutter JR Maguire M Sundberg JP Gallahan D Closson V Kitajewski J Callahan R Smith GH Stark KL Gridley T 《Genes & development》2000,14(11):1343-1352
The Notch gene family encodes large transmembrane receptors that are components of an evolutionarily conserved intercellular signaling mechanism. To assess the role of the Notch4 gene, we generated Notch4-deficient mice by gene targeting. Embryos homozygous for this mutation developed normally, and homozygous mutant adults were viable and fertile. However, the Notch4 mutation displayed genetic interactions with a targeted mutation of the related Notch1 gene. Embryos homozygous for mutations of both the Notch4 and Notch1 genes often displayed a more severe phenotype than Notch1 homozygous mutant embryos. Both Notch1 mutant and Notch1/Notch4 double mutant embryos displayed severe defects in angiogenic vascular remodeling. Analysis of the expression patterns of genes encoding ligands for Notch family receptors indicated that only the Dll4 gene is expressed in a pattern consistent with that expected for a gene encoding a ligand for the Notch1 and Notch4 receptors in the early embryonic vasculature. These results reveal an essential role for the Notch signaling pathway in regulating embryonic vascular morphogenesis and remodeling, and indicate that whereas the Notch4 gene is not essential during embryonic development, the Notch4 and Notch1 genes have partially overlapping roles during embryogenesis in mice. 相似文献
730.