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11.
Richard P Metz Xiaoyu Qu Brian Laffin David Earnest Weston W Porter 《Developmental dynamics》2006,235(1):263-271
Mouse mammary epithelial cells (HC-11) and mammary tissues were analyzed for developmental changes in circadian clock, cellular proliferation, and differentiation marker genes. Expression of the clock genes Per1 and Bmal1 were elevated in differentiated HC-11 cells, whereas Per2 mRNA levels were higher in undifferentiated cells. This differentiation-dependent profile of clock gene expression was consistent with that observed in mouse mammary glands, as Per1 and Bmal1 mRNA levels were elevated in late pregnant and lactating mammary tissues, whereas Per2 expression was higher in proliferating virgin and early pregnant glands. In both HC-11 cells and mammary glands, elevated Per2 expression was positively correlated with c-Myc and Cyclin D1 mRNA levels, whereas Per1 and Bmal1 expression changed in conjunction with beta-casein mRNA levels. Interestingly, developmental stage had differential effects on rhythms of clock gene expression in the mammary gland. These data suggest that circadian clock genes may play a role in mouse mammary gland development and differentiation. 相似文献
12.
It has now been established that circovirus infection is common in farmed geese, but little is known about the clinicopathological significance of such infections. Ten clinically diseased geese suspected of being infected by circovirus were studied by in situ hybridization using a goose circovirus DNA probe. Circovirus DNA was demonstrated in the bursa of Fabricius (BF), spleen, thymus, bone marrow, liver, kidney, lung and heart, indicating that infection can be multisystemic. In some birds, virus DNA was present in very large quantities, most notably in the BF, liver and small intestine. With the exception of BF and thymus, there were no histological findings that would have suggested the presence of such quantities of circovirus DNA. In view of the very large quantities of virus DNA labelling present in some tissues, and by analogy to porcine circovirus type 2 infection and psittacine beak and feather virus infections, which are known to cause severe disease, and which have similar virus distribution to that found in our geese, it seems probable that the circovirus was important in the disease manifestations shown by the infected geese. 相似文献
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14.
Immunoblot analyses of Candida albicans-associated antigens and antibodies in human sera. 总被引:5,自引:2,他引:5 下载免费PDF全文
M Manning-Zweerink C S Maloney T G Mitchell H Weston 《Journal of clinical microbiology》1986,23(1):46-52
We tested 10 patient sera for the presence of immunoglobulin G (IgG) antibodies to Candida albicans and for C. albicans antigens by immunoblot analysis (i.e., electrotransfer blot radioimmunoassay) (G. E. Smith and M. D. Summers, J. Virol. 39:125-137, 1981). We evaluated sera from two patients at risk for candidiasis, five patients with systemic candidiasis documented by culture, and two patients who had experienced transient candidemia. Both the specificity and the relative amount of IgG antibodies to C. albicans in each serum sample were readily visualized by this technique, as was the absence of antibody from serum of neonatal and immunocompromised patients. No antibody species appeared to be uniquely associated with candidiasis patients (i.e., each antibody species present in the candidiasis patient was also present in sera of normal individuals or "at-risk" patients). IgG from rabbits immunized with whole cells or with a cytoplasmic fraction of C. albicans was used to detect C. albicans antigens in patient sera. Although several antigens were detected in the sera from patients with candidiasis, the same antigens were also detected in sera from patients at risk and in normal human serum. No antigens were detected in human serum when preimmune rabbit sera were used. These results suggest that the antigens detected by the rabbit antisera were human serum proteins that cross-reacted with C. albicans antigens. These findings may have important implications in studies of both the pathobiology of C. albicans and the serodiagnosis of candidiasis. 相似文献
15.
Williams Weston Krueger Amy Wang Guoshen Patel Deesha Belcher Lisa 《Journal of community health》2021,46(4):832-841
Journal of Community Health - Understanding the contribution of CDC-funded testing toward diagnosing HIV informs efforts to end the HIV epidemic. Due to differences in surveillance data and CDC... 相似文献
16.
The traumatic experience of selecting and installing an in-house computer system can be eased by this guide through the forest of alternatives and sales claims confronting the prospective buyer. The authors have summarized problems common in the selection/installation process, and perhaps more important, they have detailed specific questions which should be asked in the decision-making process. The various selection criteria discussed include application software suitability, operating system software, equipment and its maintenance, ease of conversion, vendor experience and responsiveness, and cost considerations. By carefully investigating these factors as they relate to the many computer systems available, the buyer can reach a logical decision and anticipate a successful installation. 相似文献
17.
AIM: To compare assessment by MR excretory urography (MREU), Doppler ultrasound and isotope renography of women with symptomatic hydronephrosis in pregnancy and to define its cause.MATERIALS AND METHODS: Eleven women at 19-34 weeks of gestation were studied prospectively with gadolinium-enhanced breath-hold gradient echo MREU and transabdominal Doppler ultrasound compared with a 'gold standard' of isotope renography employing frusemide challenge. All studies were performed within 24 h, were reported independently in a blinded fashion and employed clearly defined criteria. Obstetric and infant outcomes were obtained.RESULTS: There were no adverse reactions to gadolinium administration in pregnancy and no adverse obstetric or infant outcomes. Three of the 11 women were unable to tolerate the complete MREU protocol. Ultrasound indices could not be used to predict ureteric obstruction as shown by isotope renography. MREU agreed with renographic findings in five of the six cases with obstruction and in two without obstruction. MREU directly demonstrated hydronephrosis to result from extrinsic compression of the ureter between the gravid uterus and iliopsoas muscle. CONCLUSION: MR excretory urography is a promising technique which affords equivalent functional and additional anatomical information to isotope renography. It is more accurate than Doppler ultrasound in the assessment of ureteric obstruction in pregnancy.Spencer, J. A. (2000). Clinical Radiology55, 446-453. 相似文献
18.
D. Bourchier P. Weston 《Archives of disease in childhood. Fetal and neonatal edition》1997,76(3):F174
AIM—To compare the efficacy of hydrocortisone with dopamine for the treatment of hypotensive, very low birthweight (VLBW) infants.METHODS—Forty infants were randomly allocated to receive either hydrocortisone (n=21) or dopamine (n=19).RESULTS—All 19 infants randomised to dopamine responded; 17 of 21 (81%) did so in the hydrocortisone group. Three of the four non-responders in the hydrocortisone group had clinically significant left to right ductal shunting. The incidence of bronchopulmonary dysplasia, retinopathy of prematurity, intraventricular haemorrhage, necrotising enterocolitis, symptomatic patent ductus arteriosus, hyperglycaemia, sepsis (bacterial or fungal) or survival did not differ between groups. The adrenocorticotrophic hormone (ACTH) stimulated plasma cortisol activity, either before or after treatment, did not differ between the two groups of infants. Although a significant difference in efficacy between dopamine and hydrocortisone was not noted (P = 0.108), there were four treatment failures in the hydrocortisone group, compared with none in the dopamine group.CONCLUSION—Both hydrocortisone and dopamine are effective treatments for hypotension in very low birthweight infants. 相似文献
19.
Miriam B Virgolini Kevin Chen Doug D Weston Mark R Bauter Deborah A Cory-Slechta 《Toxicological sciences》2005,87(2):469-482
Elevated lead (Pb) burden and high stress levels are co-occurring risk factors in low socioeconomic status (SES) children. Our previous work demonstrated that maternal Pb exposure can permanently alter hypothalamic-pituitary-adrenal (HPA) axis function and responsivity to stress challenges in offspring. The current study sought to determine the consequences of chronic Pb exposures initiated later in development combined with variable intermittent stress challenges. Male rats were exposed chronically from weaning to 0, 50, or 150 ppm Pb acetate drinking solutions (producing blood Pb levels of <5, 9-15, and 23-27 mug/dl, respectively). Pb itself decreased basal plasma corticosterone, with greater effects at 50 than 150 ppm; 150 ppm reduced both cytosolic and nuclear glucocorticoid receptor binding. Responsivity to stress challenges including novelty, cold, and restraint, was measured as changes in Fixed Interval (FI) schedule-controlled behavior in a subset of rats within each group. FI performance was modified by novelty stress only in Pb-treated rats, whereas cold and restraint stress effects were comparable across groups. Novelty elevated corticosterone equivalently across groups, but cold stress markedly increased corticosterone only in Pb-treated groups. The pattern of Pb-induced changes in serotonin (5-HT) or its metabolite 5-HIAA in frontal cortex, nucleus accumbens, striatum, and hypothalamus resembled that observed for basal corticosterone levels indicating a relationship between these variables. In addition to suggesting the potential for HPA axis-mediated effects of Pb on the central nervous system, these findings also raise questions about whether single chemicals studied in isolation from other relevant risk factors can adequately identify neurotoxic hazards. 相似文献