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排序方式: 共有1561条查询结果,搜索用时 421 毫秒
1.
Balloon dacryocystoplasty: indications and contraindications 总被引:3,自引:0,他引:3
2.
A W Dombrowski G F Bills G Sabnis L R Koupal R Meyer J G Ondeyka R A Giacobbe R L Monaghan R B Lingham 《The Journal of antibiotics》1992,45(5):671-678
A novel cytochalasin, L-696,474, (18-dehydroxy cytochalasin H) that inhibits HIV-1 protease was discovered in fermentations of a bark-inhabiting Ascomycete, Hypoxylon fragiforme. The product was first identified from extracts of an agar medium. Fermentation studies on a number of media indicated that the product can be made on several solid and liquid media. Optimum production was obtained from growth in a complex medium composed of glycerol, glucose, citrate, Ardamine, soybean meal, tomato paste, and inorganic salts. Other Hypoxylon spp., related species of Xylariales, and other fungi known to produce cytochalasins, were also surveyed for their ability to make L-696,474. Only one other Hypoxylon fragiforme isolate was found to make this novel cytochalasin; none of the other cultures surveyed made L-696,474 or any other compounds which inhibit HIV-1 protease. 相似文献
3.
Duncan WC; Illingworth PJ; Young FM; Fraser HM 《Human reproduction (Oxford, England)》1998,13(9):2532-2540
The molecular mechanisms involved in luteolysis are still unclear in the
primate. This study aimed to investigate the effect of induced luteolysis
on the ovarian luteinizing hormone (LH) receptor and the steroidogenic
enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset
monkey. Luteolysis was induced in the mid-luteal phase either directly by
systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal
using systemic gonadotrophin releasing hormone antagonist (GnRHant)
treatment. The LH receptor was studied by isotopic mRNA in-situ
hybridization and in-situ ligand binding and 3beta-HSD expression was
studied using isotopic mRNA in-situ hybridization and immunohistochemistry.
Induced luteolysis was associated with a reduction in the expression of LH
receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a
reduction in the LH receptor (P < 0.05) and 3beta-HSD protein
concentrations within 24 h. There were no differences in the findings
whether luteolysis was induced with PGF2alpha or GnRHant. This study shows
that disparate mechanisms to induce luteolysis in the primate result in an
identical rapid loss of the LH receptor and 3beta-HSD. In conclusion,
induced luteolysis leads to rapid loss of the steroidogenic pathway in
luteal cells.
相似文献
4.
HM Clink 《Journal of clinical pathology》1980,33(8):799-800
5.
The neuroendocrine stress hormone norepinephrine augments Escherichia coli O157:H7-induced enteritis and adherence in a bovine ligated ileal loop model of infection
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Vlisidou I Lyte M van Diemen PM Hawes P Monaghan P Wallis TS Stevens MP 《Infection and immunity》2004,72(9):5446-5451
The role of the neuroendocrine environment in the pathogenesis of enteric bacterial infections is increasingly being recognized. Here we report that norepinephrine augments Escherichia coli O157:H7-induced intestinal inflammatory and secretory responses as well as bacterial adherence to intestinal mucosa in a bovine ligated ileal loop model of infection. Norepinephrine modulation of enteritis and adherence was dependent on the ability of E. coli O157:H7 to form attaching and effacing lesions. 相似文献
6.
7.
David C. H. Benton Alan S. Monaghan Ramine Hosseini Parmvir K. Bahia Dennis G. Haylett Guy W. J. Moss 《The Journal of physiology》2003,553(1):13-19
The rat SK1 gene ( rSK1 ) does not form functional Ca2+ -activated potassium channels when expressed alone in mammalian cell lines. Using a selective antibody to the rSK1 subunit and a yellow fluorescent protein (YFP) tag we have discovered that rSK1 expression produces protein that remains largely at intracellular locations. We tested the idea that rSK1 may need an expression partner, rSK2, in order to form functional channels. When rSK1 was co-expressed with rSK2 in HEK 293 cells it increased the current magnitude by 77 ± 34 % (as compared with cells expressing rSK2 alone). Co-expression of rSK1 with rSK2 also changed the channel pharmacology. The sensitivity of SK current to block by apamin was reduced ~16-fold from an IC50 of 94 p m (for SK2 alone) to 1.4 n m (for SK2 and SK1 together). The sensitivity to block by UCL 1848 (a potent small molecule blocker of SK channels) was similarly reduced, ~26-fold, from an IC50 of 110 p m to 2.9 n m . These data clearly demonstrate that rSK1 and rSK2 subunits interact. The most likely explanation for this is that the subunits are able to form heteromeric assemblies. 相似文献
8.
9.
D Raghavan E Heyderman P Monaghan J Gibbs E Ruoslahti M J Peckham A M Neville 《Journal of clinical pathology》1981,34(2):123-128
A xenograft line, HX 53, has been established in immune-suppressed mice from a specimen of a lymph node metastasis in a patient with a histological diagnosis of seminoma but with markedly raised circulating levels of alpha-fetoprotein. Histological, immunocytochemical, and ultrastructural studies of this xenograft line have suggested that a solid variant of yolk sac carcinoma may exist, which morphologically resembles seminoma, or that a continuum of differentiation exists between seminoma and yolk sac carcinoma. 相似文献
10.
Seventy-two samples of infant breasts, aged from newborn to 2 years, were collected at necropsy. Whole-mount preparations and histological sections were made. A system of classification was devised to study the extent of the structural development of the ductal system (morphological types I, II, and III) and the functional differentiation of the lining epithelium (functional stages I to V). There was no correlation between the age of the infant and the type of development of the ductal system. In contrast, the epithelial differentiation followed a chronological pattern, starting with secretory changes and apparently going through a period characterized by apocrine metaplasia before post-secretory involution. These epithelial changes were not associated with the morphological type of the ductal system. There were no distinguishing features between the breasts from the two sexes. Immunoperoxidase staining for actin and kappa-casein was carried out to study the myoepithelial cells and secretory cells, respectively. Myoepithelial cells were present at all stages and prominent staining for casein was observed up to 2 months of age. Embryonic-type adipose tissue was seen in 7 cases, in one of which it was associated closely with the developing ductal system. Extramedullary hematopoiesis was observed in the periductal connective tissue until 4 months of age. This paper describes the most extensive anatomical and histological study of the human infant breast to date and lays the foundation for a detailed study of the epithelial and stromal changes that take place during human breast development. 相似文献