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1.
The antiproliferative, cytotoxic and apoptogenic activities of Bufo melanostictus (Indian common toad) skin extract (TSE) on U937 and K562 leukemic cell line has been investigated. TSE significantly (P<0.001) reduced the time-dependent cell proliferation and decreased MTT values in U937 and K562 cells. TSE (IC50 doses) suppressed the proliferating cell nuclear antigen expression in both the cells. It was demonstrated that, TSE (IC50 doses) primarily arrested the U937 and K562 cells at G1 phase of the cell cycle. Confocal microscopy showed the altered fragmented nuclei and apoptotic bodies formation in TSE (IC50 doses) treated U937 and K562 cells. Membrane blebbing, cell surface shrinkage and perforation were observed through scanning electron microscope. TSE-induced DNA fragmentation in U937 and K562 cells was reflected in single-cell gel electrophoresis. TSE significantly (P<0.001) increase the length-width ratio of DNA mass as compared to control in comet assay. The flow cytometric analysis of annexin-V binding to the cancer cells further supported the apoptotogenic activity of TSE. The effect of TSE on normal human peripheral blood mononuclear cells viability and cytotoxicity was studied in culture and found to be less cytotoxic than on the U937 and K562 cells. The findings from the present study suggested that TSE might possess potent antineoplastic agent having antiproliferative, cytotoxic and apoptogenic activity against U937 and K562 myeloid leukemic cells. 相似文献
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Effect of ethanol on cyclic AMP levels in intact PC12 cells 总被引:4,自引:0,他引:4
Two subclones of the rat pheochromocytoma cell line, PC12, were used to compare the effects of ethanol on adenylate cyclase activity in isolated membranes with its effects on cyclic AMP accumulation in intact cells. Consistent with previous reports, ethanol increased basal and 2-chloroadenosine-stimulated adenylate cyclase activity in isolated membrane preparations from both subclones. However, ethanol had opposite effects on agonist-stimulated cyclic AMP accumulation in intact cells of the two subclones, enhancing accumulation in one subclone, and inhibiting it in the other. The inhibition of cyclic AMP accumulation did not result from stimulation of phosphodiesterase activity, activation of the inhibitory guanyl nucleotide regulatory protein, Gi, or stimulation of protein kinase C. The results indicate that extrapolation of the effects of ethanol from one cell type to another, or from in vitro to in vivo systems, may be complicated by the interaction of ethanol with regulatory processes that influence second messenger systems, and can differ in various types of intact cells. 相似文献
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M Kaplan HJ Vreman C Hammerman C Leiter B Rudensky MG MacDonald DK Stevenson 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(4):455-457
The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia. 相似文献
6.
Induction of sister chromatid exchanges by cypermethrin and carbosulfan in bone marrow cells of mice in vivo 总被引:1,自引:0,他引:1
The public health effects of pesticides cannot be denied. However, the undesired effects of chemical pesticides have been recognized as a serious public health concern during the past decades. The present study describes the genotoxic effects of two pesticides, namely cypermethrin and carbosulfan, in a murine test system in vivo. The test parameter used was analysis of sister chromatid exchanges (SCE) in bone marrow cells. Both cypermethrin (5, 10 and 20 mg/kg) and carbosulfan (1.25, 2.5 and 5 mg/kg) induced significant increases in the frequency of SCEs (P < 0.001). However, no significant dose-response correlation could be found for either of the pesticides. Carbosulfan induced a cell cycle delay, as evidenced by an increase in average generation time accompanied by accumulation of cells in the first division cycle, but cypermethrin did not induce any such response. The present study indicates that carbosulfan has a higher potential to cause genetic alterations than cypermethrin in mice and may also pose a mutagenic risk to human beings. 相似文献
7.
The response of the rat tracheal epithelium to ozone exposure. Injury, adaptation, and repair. 总被引:1,自引:4,他引:1 下载免费PDF全文
K. J. Nikula D. W. Wilson S. N. Giri C. G. Plopper D. L. Dungworth 《The American journal of pathology》1988,131(2):373-384
Although acute ozone (O3) exposure injures tracheal epithelium, the response of the tracheal epithelium to prolonged O3 exposure, and the degree of repair following cessation of exposure have not been previously reported. The purpose of this experiment was to characterize the morphologic response of rat tracheal epithelium to acute (3 days) and prolonged (60 days) exposure to 0.96 ppm O3 as well as to evaluate repair in a 7- and 42-day post-60-day exposure period. Quantitative light- and electron-microscopic evaluation and thymidine labeling indices showed that after 3 days of O3 exposure there was ciliary damage, cell necrosis, an increased density of intermediate cells, and an elevated thymidine labeling index. Following 60 days of exposure, the only major change from controls was the presence of ciliated cells with uniformly short cilia. Tracheal superoxide dismutase levels did not differ between control and 60-day exposure groups. Our findings suggest that the tracheal epithelium adapts to prolonged ozone exposure with the exception of cilia formation in ciliated cells. Complete epithelial recovery occurred by 42 days after exposure. 相似文献
8.
Arsenic (As) contamination in ground water has affected more than 19 countries. Approximately 36 million people in the Bengal delta alone are exposed to this toxicant via drinking water (>50 microg/l) and are at potential health risk. Chronic ingestion of As via drinking water is associated with occurrence of skin lesions, cancer and other arsenic-induced diseases in West Bengal, India. An in vitro cytogenetic study was performed utilizing chromosomal aberrations (CA) in lymphocytes treated with sodium arsenite (0-5 microM) in six symptomatic (having arsenic-related skin lesions) individuals, six age- and sex-matched As-exposed asymptomatic (no arsenic-related skin lesions) individuals and six control individuals with similar socio-economic status residing in non-affected districts of West Bengal with no evidence of As exposure. The mean As content in nails and hair was 9.61 and 5.23 microg/g in symptomatic, 3.48 and 2.17 microg/g in asymptomatic and 0.42 and 0.33 microg/g in the control individuals, respectively. The main aim of our study was to determine whether genotoxic effects differed in the lymphocytes of the control (no exposure to arsenic), asymptomatic and symptomatic individuals after in vitro treatment with sodium arsenite. Although both the exposed groups had chronic exposure to As through the drinking water, individuals with skin lesions accumulated more As in their nails and hair and excreted less in urine (127.80 versus 164.15 microg/l). The results show that sodium arsenite induced a significantly higher percentage of aberrant cells in the lymphocytes of control individuals than in the lymphocytes of both the exposed groups. Within the two exposed groups As induced higher incidences of CA in the symptomatic than the asymptomatic individuals. These results suggest that asymptomatic individuals have relatively lower sensitivity and susceptibility to induction of genetic damage by As compared with the symptomatic individuals. 相似文献
9.
Immunohistology of oestrogen receptor and D5 antigen in breast cancer: correlation with oestrogen receptor content of adjacent cryostat sections assayed by radioligand binding and enzyme immunoassay. 总被引:1,自引:1,他引:1 下载免费PDF全文
D D Giri V J Dangerfield R Lonsdale K Rogers J C Underwood 《Journal of clinical pathology》1987,40(7):734-740
Two monoclonal antibodies recognising epitopes associated with oestrogen receptor protein were evaluated against the assayable soluble oestrogen receptor concentration in a series of 149 breast carcinomas. One antibody (anti-ER) recognises the hormone binding unit of oestrogen receptor and gives nuclear staining; the other antibody (anti-D5) was raised to a component of soluble oestrogen receptor and gives cytoplasmic staining. To minimise variations attributable to tumour heterogeneity and sampling error immunohistology using the two monoclonal antibodies, radioligand binding assays, enzyme immunoassays, and quantitative histology were done on adjacent frozen sections. Thirty nine per cent, 48%, 54%, and 43% of the tumours were found to be oestrogen receptor positive by radioligand binding assay, anti-ER and anti-D5 immunohistology, and enzyme immunoassay, respectively. Strong correlations (p less than 0.0005) were found between anti-ER immunohistology and the radioligand binding assay. Only weak correlations were found between anti-D5 immunohistology and the results of other assay methods for oestrogen receptor. Nuclear staining of human breast cancers with the anti-ER monoclonal antibody thus seems to be an acceptable alternative to biochemical assays, with the additional advantage of showing intercellular and regional heterogeneity for oestrogen receptor content. 相似文献
10.
Kamesh?R?Ayasolla Shailendra?Giri Avtar?K?Singh Inderjit?SinghEmail author 《Journal of neuroinflammation》2005,2(1):21