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91.
TLR2 activation by proteosomes promotes uptake of particulate vaccines at mucosal surfaces 总被引:1,自引:0,他引:1
Chabot SM Chernin TS Shawi M Wagner J Farrant S Burt DS Cyr S Neutra MR 《Vaccine》2007,25(29):5348-5358
Proteosome-based vaccines have TLR2-based adjuvant activity and show promise for mucosal immunization. We examined the effects of proteosomes on mucosal uptake in Peyer's patches in vivo. Proteosomes accelerated transepithelial transport of microparticles by M cells and induced migration of dendritic cells (DCs) into the follicle-associated epithelium (FAE); both effects were dependent on TLR2. Proteosomes induced the release of the DC-attracting chemokine MIP3alpha from Caco-2 epithelial cells in vitro. In HEK cells, proteosome-mediated MIP3alpha release was dependent on TLR2 expression and matrix metalloproteinase activation. Thus, TLR2 activation by proteosomes may promote mucosal uptake of particulate vaccines, and this may contribute to their adjuvanticity. 相似文献
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Ovarian follicles isolated from rainbow trout during early exogenous vitellogenesis were used to study the in vitro effects of thyroid hormones on salmon gonadotropin (GtH)-induced estradiol-17 beta (E2) secretion. Triiodothyronine (T3) alone did not alter E2 secretion but T3 in the presence of GtH (0.5 micrograms/ml) modified E2 secretion according to a biphasic dose-response curve. Maximum E2 secretion occurred at 1.9 x 10(-8) M T3; a concentration of 3.0 x 10(-7) M was inhibitory. T3 was more potent in stimulating GtH-induced E2 secretion than thyroxine. The stimulatory and inhibitory effects of T3 were consistent over a range of GtH concentrations (0.1-1.0 micrograms/ml). Cycloheximide (0.1-10 microM) decreased E2 secretion by GtH-treated follicles in a dose-dependent manner, but failed to overcome all the stimulatory effects of T3. Time course studies with follicles incubated with GtH, GtH + T3, GtH + cycloheximide, or GtH + T3 + cycloheximide indicated that T3 stimulation of GtH-induced E2 secretion occurs within 6 hr. It is concluded that thyroid hormones amplify the effects of GtH on E2 secretion by isolated ovarian follicles; at least a part of this effect does not require de novo protein synthesis. 相似文献
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Ways DK; Qin W; Riddle RS; Garris TD; Bennett TE; Steelman LS; McCubrey JA 《Blood》1991,78(10):2633-2641
FD/PMA is a subclone of the interleukin-3 (IL-3)-dependent, FDC-P1 cell line, which proliferates in response to either 12-O- tetradecanoylphorbol-13 acetate (PMA) or IL-3. While several endogenous substrates were phosphorylated in response to protein kinase C (PKC) activation in FDC-P1, phospholipid-dependent phosphorylation in the FD/PMA grown in PMA was not observed. Basal, phosphatidylserine- independent, and diolein-independent phosphorylation of cytosolic substrates with molecular weights of 17, 52, 57, and 105 Kd were enhanced in FD/PMA cells grown in PMA as compared with FDC-P1 cells cultured in IL-3. Phosphorylation of a 105-Kd substrate was enhanced in the particulate fraction of FD/PMA cells maintained in PMA. The 17-Kd substrate in FD/PMA cells comigrated with a substrate phosphorylated in a PKC-dependent manner in FDC-P1 cells. Phosphorylation of the 52- and 57-Kd substrates, but not of the 17-Kd substrate, was inhibited by H-7 and staurosporine. A portion of the PMA-induced cytosolic kinase activity coeluted with PKC on diethyl aminoethyl chromatography. While FD/PMA cells cultured in PMA contained negligible PKC-dependent phosphorylation of endogenous substrates or histone, alpha and epsilon PKC isoforms were detected by Western blot analysis. PKC phosphotransferase activity was observed in FD/PMA cells grown in PMA when peptides corresponding to residues 720 to 737 of PKC-epsilon or residues 4 to 14 of myelin basic protein were used as substrates. These data indicate that maintenance of FD/PMA cells in PMA stimulates proliferation and markedly alters PKC substrate specificity. Generation of at least two phospholipid-independent kinases occurs in PMA-treated cells. 相似文献
97.
Serum levels of thyroid hormones (T4 = L-thyroxine and T3 = 3,5,3'-triiodo-L-thyronine) were measured and correlated with previously published levels of 17 beta-estradiol, testosterone (T), and Ca2+ (index of vitellogenin) in four groups of female trout held for 1-3 years at 8.5-9.0 degrees on a ration of 0.5% of body weight day-1 under different constant photoperiod regimes. In group 1, trout under a regimen of 18L:6D became sexually mature (SM) in April/May and then SM again in September/October; in group 2, trout under a regimen of 6L:18D became SM in January/February; in group 3, trout under a regimen of 6L:18D became SM in March/April; in group 4 trout under a regimen of 18L:6D followed by 10L:14D became SM in September/October. In all groups, regardless of the photoperiod-induced changes in spawning time, serum T3 exceeded T4 and both serum T3 and T4 patterns showed a consistent relationship with the sequence of steroid hormone changes and spawning time. Thyroid hormone levels were high during previtellogenesis but fell as sex steroids and serum Ca2+ increased. T3 and T4 were lowest before spawning when sex steroids were at their peak and then increased sharply following spawning as sex steroid levels declined. Peak serum T coincided with ovulation and usually preceded the postreproductive surge in serum T3 and T4. The hypothesis is discussed that T3 enhances early ovarian development, but as energy-demanding vitellogenesis proceeds T3 formation is suppressed, thereby curtailing growth and favoring energy partition to the ova. 相似文献
98.
Thompson OM Ballew C Resnicow K Must A Bandini LG Cyr H Dietz WH 《International journal of obesity (2005)》2004,28(2):282-289
OBJECTIVES: To assess the relationship between eating food purchased away from home (FAH) and longitudinal change in body mass index (BMI) z-score among girls, and to assess the longitudinal tracking of eating FAH from childhood through adolescence. DESIGN: Participants kept 7-day dietary records at two points in time. The records included the place and time for all foods consumed. We recorded how often participants ate FAH, calculated the percent of total energy derived from FAH, and classified foods as quick-service food, coffee-shop food, or restaurant food. PARTICIPANTS: Healthy girls (n=101) between the ages of 8 and 12 y at baseline and 11 and 19 y at follow-up participated in a longitudinal study of growth and development at the Massachusetts Institute of Technology. STATISTICAL ANALYSES: Analysis of variance was used to assess the relationship between change in BMI z-score and both the frequency of eating FAH and energy derived from eating FAH. The participants' baseline BMI z-score was a significant covariate and was controlled for in both models. We used the kappa coefficient to assess FAH tracking from childhood through adolescence. RESULTS: The frequency of eating quick-service food at baseline was positively associated with change in BMI z-score (F=6.49, P<0.01). Participants who ate quick-service food twice a week or more at baseline had the greatest mean increase in BMI z-score compared to those who ate quick-service food once a week or not at all. Quick-service food eating tracked slightly from childhood through adolescence (k=0.17, P<0.05). DISCUSSION: Adolescent girls who eat quick-service food twice a week or more are likely to increase their relative BMI over time. 相似文献
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Mark Daniels Stephanie N. DuBose David M. Maahs Roy W. Beck Larry A. Fox Rose Gubitosi-Klug Lori M. Laffel Kellee M. Miller Heather Speer William V. Tamborlane Michael J. Tansey for the TD Exchange Clinic Network 《Diabetes care》2013,36(9):2639-2645