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1.
International Journal of Clinical Oncology - The practice of cancer diagnosis disclosure to children has been changed with the times. The regulations of clinical trials in the 2000s might change...  相似文献   
2.
Some physiological substances, including acetylcholine and nitric oxide, are useful candidates for stimulation of intestinal absorption of drugs. In the present study, we elucidated the ability of epinephrine (Epi) to stimulate the intestinal absorption of drugs. We evaluated the ability of Epi to enhance absorption of macromolecules using dextran (Mw 4000 Da), which is poorly absorbed from the intestine, as a model compound in situ in a closed loop of the rat jejunum. Treatment of the jejunum with Epi resulted in significant increase in absorption of dextran in a dose-dependent fashion. The area under the curve (AUC) from 0 to 4 h in the Epi-treated jejunum was 13-fold higher than that in the vehicle-treated jejunum. The absorption-enhancing activity of Epi was 40-fold higher than that of caprate, a clinically used absorption-enhancer of drugs. In the experimental conditions used in this study, histological injury of the mucosa and perturbation of the mucosal membrane were not observed in the Epi-treated jejunum. Treatment with an antagonist of alpha-adrenergic receptors attenuated the stimulation of intestinal absorption by Epi, and treatment with an agonist of alpha-adrenergic receptors resulted in enhancement of intestinal absorption. While an antagonist of beta-adrenergic receptors enhanced the absorption-enhancing effect of Epi, an agonist of beta-adrenergic receptors stimulated intestinal absorption. These results indicate that stimulation of adrenergic receptors may be a novel strategy for intestinal absorption of drugs.  相似文献   
3.
We previously reported that the Guardian Bio-Threat Alert (BTA) system could detect (detection limit: about 0.1 μg/ml) staphylococcal enterotoxin B (SEB), botulinum toxins (BTX) A and B, and ricin, with no interference by white-powdered materials or colored matrices. In this study, the capability of the BTA system was further assessed. With 10 min of preheating at 60°C, all toxins could be detected, but with preheating at 80°C, BTX A and B and ricin became undetectable. About 20% SEB could be detected after heating at 80°C, but this detection ability was completely removed after heating at 100°C. The effects of chemicals usually used for decontamination, such as sodium hypochlorite, hydrogen peroxide, formaldehyde, and sodium nitrite, on the detectability of SEB, BTX A, or ricin in the BTA system were also tested. The concentrations giving 50% line intensity for SEB, BTX A, and ricin were 3.1, 11, and 15 μM for sodium hypochlorite and 88, 210, and 60 mM for formaldehyde, respectively. The addition of hydrogen peroxide or sodium nitrite did not decrease the detectability even when used at high concentrations.  相似文献   
4.
We found that a chemokine receptor gene, CCR1, acts downstream of NFAT2 in RANKL-stimulated RAW264 and bone marrow cells. The upstream regulatory region of CCR1 showed RANKL-dependent and CsA-suppressible promoter activity. Downregulation of the expression and function of CCR1 suppressed cell migration. INTRODUCTION: We previously reported that the expression of NFAT2 induced by RANKL is a key process for progression to multinucleated cells in an in vitro osteoclastogenesis system. Identifying the target genes of NFAT2 would thus be informative about the differentiation process. We focused here on chemokine and chemokine receptor genes that act downstream of NFAT2 in RAW264 cells as well as osteoclast precursors prepared from bone marrow cells. MATERIALS AND METHODS: RAW264 mouse monocyte/macrophage line cells were cultured with or without cyclosporin A (CsA) in the presence of RANKL or glutathione S-transferase (GST). Osteoclast precursors were prepared from bone marrow cells. RANKL-inducible and CsA-suppressible genes were searched for by microarray analysis, and expression was confirmed by quantitative RT-PCR. Promoter activity was measured by luciferase gene reporter assay. Short interfering (si)RNA for CCR1 was introduced in RAW264 cells. Cell migration activity was examined using a Boyden chamber assay. RESULTS AND CONCLUSIONS: We identified the chemokine receptor gene CCR1 as a gene showing significant differential expression profiles in osteoclastogenesis in the presence versus the absence of CsA, an inhibitor of NFAT. This property was unique to CCR1 among the chemokine and chemokine receptor genes examined in both RAW264 and bone marrow cells. The upstream regulatory region was isolated from CCR1, and its RANKL-dependent and CsA-suppressible promoter activity was confirmed. The functional significance of CCR1 was assessed by monitoring the migration of cells in a transwell migration assay, and this activity was abolished when either CsA- or CCR1 siRNA-treated cells were used. Moreover, treatment with a Galpha inhibitor pertussis toxin (PTX) or methiolynated-regulated on activation, normal T cells expressed and secreted (Met-RANTES), an antagonist of CCR1, suppressed multinucleated cell formation in the bone marrow cell system. Together, these results suggest that the CCR1 signaling cascade is under the control of NFAT2 and seems to enhance the migration of differentiating osteoclasts.  相似文献   
5.
Traf6 is essential for murine tooth cusp morphogenesis.   总被引:5,自引:0,他引:5  
Ectodermal appendages such as skin, hair, teeth, and sweat glands are affected in patients with hypohidrotic (anhydrotic) ectodermal dysplasia (HED). It has been established that mutations in the tumor necrosis factor (TNF) superfamily of molecules, i.e., ectodysplasin (EDA), EDA receptor (EDAR), and EDAR-associated death domain (EDARADD; the intracellular adaptor for EDAR), are responsible for several forms of HED in humans and mice. We show here by in situ hybridisation that another TNF family (orphan) receptor, TROY (also known TAJ, TAJ-alpha, TRADE, and TNFRSF19), is strongly coexpressed with Edar in the epithelial enamel knot signalling centres that are believe to regulate cuspal morphogenesis during murine tooth development. Traf6 is known to function as an intracellular adaptor protein for Troy and examination of Traf6 mutant mice revealed abnormalities in molar teeth that are similar but more severe than those produced by mutations in Eda signalling molecules. This finding suggests that, in additional to ectodysplasin, another TNF pathway involving Troy/Traf6 is involved in molar tooth cusp formation and identifies an essential role for a Traf in tooth development. Developmental Dynamics 229:131-135, 2004.  相似文献   
6.
A simple and rapid method for purifying merozoites ofTheileria sergenti from infected bovine erythrocytes was developed. Infected erythrocytes were lysed by the use of a cytolytic toxin produced byAeromonas hydrophila and the lysate was subjected to ultracentrifugation in a Percoll discontinuous density gradient. Pure and morphologically intact merozoites free of erythrocyte membrane were recovered from a band formed at the interface of 40% and 60% (by vol.) Percoll solutions. In this merozoite fraction, contamination of erythrocyte membrane proteins was not detected as examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.  相似文献   
7.
In various arterial lesions including atherosclerotic lesions, the main morphological change involves smooth muscle cells. The potential sensitivity is different among the arterial smooth muscle cells, venous smooth muscle cells and smooth muscle cells of other organs. The modified smooth muscle cells characterized by the increase of rough endoplasmic reticula are considered to express their latent ability to synthesize collagen fibers, elastic fibers and other ground substances.
The foam cells noted in atherosclerosis and fatty streak consist of lipid accumulated smooth muscle cells and hematogenous macrophages. Lipid metabolism and synthesis in the latter differ from those in the former. The ratio of the two kinds of foam cells in atheroma or fatty streak varies by the stage of the lesion.
It is possible to suppose that there exists a factor which would selectively attack the media smooth muscle cells of small arteries or arterioles. This is observed electron microscopically as focal cytoplasmic necrosis (cytoplasmolysis) of smooth muscle cells and plays an important role in the histogenesis of fibrinoid necrosis.
In case of experimental periarteritis nodosa the early stage begins with cytoplasmolysis of smooth muscle cells and marked increase of rough endoplasmic reticula in adjacent smooth muscle cells.  相似文献   
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10.
Using immunoperoxidase methods, 94 human adrenal tumors were examined for evidence of immunoreactivity and receptor expression of insulinlike growth factor I (IGF-I) and insulin. The frequency of IGF-I in adrenocortical carcinomas was significantly higher than that in adenomas of the adrenal glands. The adrenocortical carcinomas showed strong intensity of staining for IGF-I, IGF-I receptors, and insulin receptors. A significant correlation between immunoreactivity and receptor expression of both IGF-I and insulin was found only in the adrenocortical carcinomas. The adrenocortical adenomas with Cushing's syndrome and pheochromocytomas, more than adrenocortical adenomas with Conn's syndrome, also stained strongly for insulin receptors. Thus the IGF-I and insulin probably play a role in the growth of adrenocortical carcinoma tissues, possibly through autocrine mechanisms. The expression of insulin receptors in adrenocortical adenomas in the presence of Cushing's syndrome and pheochromocytomas may be associated with functions.  相似文献   
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