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51.
Jedrychowski W Masters E Choi H Sochacka E Flak E Mroz E Pac A Jacek R Kaim I Skolicki Z Spengler JD Perera F 《International journal of occupational and environmental health》2007,13(2):175-180
A cohort study assessed the relationship between dietary intake of vitamin A in 493 healthy mothers before and around conception and adverse birth outcomes associated with environmental toxicant exposures. The cohort, non-smoking women with singleton pregnancies, aged 18-35 years, gave birth at 34-43 weeks of gestation. The women were asked about their diets over one year preceding pregnancy. Measurements of PM2.5 were carried out during the second trimester. Birth outcomes were adjusted for potential confounding factors, including gestational age. Standardized beta regression coefficients confirmed an inverse association between PM2.5 and birth weight (beta = -172.4, p = 0.02), but the effect of vitamin A on birth weight was positive (beta = 176.05, p = 0.05), when the two were adjusted for each other. The negative effect of higher prenatal PM2.5 exposures (above third tertile) on birth weight was significant in women below the third tertile of vitamin A intakes (beta = -185.1, p = 0.00), but not in women with higher intakes (beta = 38.6, p = 0.61). The negative effect of higher PM2.5 exposure on length at birth was significant with lower vitamin A intakes (beta = -1.1, p = 0.00) but not with higher intakes (beta = -0.3, p = 0.56). Prepregnancy nutrition of mothers may modulate the harmful effects of prenatal exposures to pollutants on birth outcomes. 相似文献
52.
Direct demonstration that autologous bone marrow transplantation for solid tumors can return a multiplicity of tumorigenic cells 总被引:5,自引:2,他引:5
Rill DR; Santana VM; Roberts WM; Nilson T; Bowman LC; Krance RA; Heslop HE; Moen RC; Ihle JN; Brenner MK 《Blood》1994,84(2):380-383
Patients with solid tumors are increasingly being treated by autologous bone marrow transplantation (BMT). Although response rates appear to be increased, disease recurrence is the commonest cause of treatment failure. Whether relapse is entirely due to residual disease in the patient or arises also from infiltrating malignant cells contained in the autologous marrow transplant has not been resolved. If the latter explanation is correct, then purging would be required as part of the transplantation procedure. We used retrovirally mediated transfer of the neomycin-resistance gene to mark BM harvested from eight patients with neuroblastoma in clinical remission. The marked marrow cells were subsequently reinfused as part of an autologous BMT. At relapse, we sought the marker gene in malignant cell populations. Three patients have relapsed, and in each the marker gene was detected by phenotypic and genetic analyses of resurgent malignant cells at medullary and extramedullary sites. Analysis of neuroblast DNA for discrete marker gene integration sites suggested that at least 200 malignant cells, each capable of tumor formation, were introduced with the autologous marrow transplant and contributed to relapse. Thus, autologous BMTs administered to patients with this solid tumor may contain a multiplicity of malignant cells that subsequently contribute to relapse. The marker-gene technique we describe should permit evaluation of the mechanisms of relapse and the efficacy of purging in patients receiving autologous marrow transplantation for other solid tumors that infiltrate the marrow. 相似文献
53.
L Laval R Martin JN Natividad F Chain S Miquel C Desclée de Maredsous S Capronnier H Sokol EF Verdu JET van Hylckama Vlieg LG Bermúdez-Humarán T Smokvina P Langella 《Gut microbes》2015,6(1):1-9
Impaired gut barrier function has been reported in a wide range of diseases and syndromes and in some functional gastrointestinal disorders. In addition, there is increasing evidence that suggests the gut microbiota tightly regulates gut barrier function and recent studies demonstrate that probiotic bacteria can enhance barrier integrity. Here, we aimed to investigate the effects of Lactobacillus rhamnosus CNCM I-3690 on intestinal barrier function. In vitro results using a Caco-2 monolayer cells stimulated with TNF-α confirmed the anti-inflammatory nature of the strain CNCM I-3690 and pointed out a putative role for the protection of the epithelial function. Next, we tested the protective effects of L. rhamnosus CNCM I-3690 in a mouse model of increased colonic permeability. Most importantly, we compared its performance to that of the well-known beneficial human commensal bacterium Faecalibacterium prauznitzii A2-165. Increased colonic permeability was normalized by both strains to a similar degree. Modulation of apical tight junction proteins expression was then analyzed to decipher the mechanism underlying this effect. We showed that CNCM I-3690 partially restored the function of the intestinal barrier and increased the levels of tight junction proteins Occludin and E-cadherin. The results indicate L. rhamnosus CNCM I-3690 is as effective as the commensal anti-inflammatory bacterium F. prausnitzii to treat functional barrier abnormalities. 相似文献
54.
Jedrychowski W Perera FP Tang D Stigter L Mroz E Flak E Spengler J Budzyn-Mrozek D Kaim I Jacek R 《Nutrition (Burbank, Los Angeles County, Calif.)》2012,28(4):372-377
ObjectiveWe previously reported an association between prenatal exposure to airborne polycyclic aromatic hydrocarbons (PAH) and lower birth weight, birth length, and head circumference. The main goal of the present analysis was to assess the possible impact of coexposure to PAH-containing barbecued meat consumed during pregnancy on birth outcomes.Materials and methodsThe birth cohort consisted of 432 pregnant women who gave birth at term (>36 wk of gestation). Only non-smoking women with singleton pregnancies, 18–35 y of age, and who were free from chronic diseases such as diabetes and hypertension, were included in the study. Detailed information on diet over pregnancy was collected through interviews and the measurement of exposure to airborne PAHs was carried out by personal air monitoring during the second trimester of pregnancy. The effect of barbecued meat consumption on birth outcomes (birth weight, length, and head circumference at birth) was adjusted in multiple linear regression models for potential confounding factors such as prenatal exposure to airborne PAHs, child's sex, gestational age, parity, size of mother (maternal prepregnancy weight, weight gain in pregnancy), and prenatal environmental tobacco smoke.ResultsThe multivariable regression model showed a significant deficit in birth weight associated with barbecued meat consumption in pregnancy (coeff = ?106.0 g; 95%CI: ?293.3, ?35.8). The effect of exposure to airborne PAHs was about the same magnitude order (coeff. = ?164.6 g; 95%CI: ?172.3, ?34.7). Combined effect of both sources of exposure amounted to birth weight deficit of 214.3 g (95%CI: ?419.0, ?9.6). Regression models performed for birth length and head circumference showed similar trends but the estimated effects were of borderline significance level. As the intake of barbecued meat did not affect the duration of pregnancy, the reduced birth weight could not have been mediated by a shortened gestation period.ConclusionIn conclusion, the study results provided epidemiologic evidence that prenatal PAH exposure from diet including grilled meat might be hazardous for fetal development. 相似文献
55.
The inappropriate expression of c-myc in cells deprived of growth factors has recently been implicated in the activation of programmed cell death (apoptosis). The studies described here examine the ability of interleukin-3 (IL-3) or erythropoietin (Epo) to suppress apoptosis that occurs in association with enforced myc expression during cell cycle arrest of a murine IL-3-dependent myeloid progenitor cell line, 32D. G1 arrest was observed when culturing 32D cells to high density in medium supplemented with IL-3, or at subconfluent densities in medium supplemented with Epo. Under both conditions, endogenous c-myc expression was downregulated and viability was maintained. In clones of cells in which c-myc is constitutively expressed from a retroviral vector, enforced c-myc expression was associated with the activation of apoptosis at high cell densities. Similarly, enforced c-myc expression was deleterious to cell survival when these cells were cultured in Epo, as apoptosis was evident within 6 hours. The results support the concept that inappropriate c-myc expression activates apoptosis and that neither IL-3 nor Epo can suppress this program under these conditions. 相似文献
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In a preterm infant, chest tubes were inserted for treatment of bilateral pneumothoraces. Hemorrhagic pericardial effusion with cardiac tamponade developed, probably resulting from traumatic injury by the left chest tube. The infant survived due to timely diagnostic and therapeutic intervention. No recurrence of pericardial effusion was seen and follow-up showed normal psychomotor development. 相似文献
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