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21.
The role of size, sequence and haplotype in the stability of FRAXA and FRAXE alleles during transmission 总被引:2,自引:5,他引:2
Murray A; Macpherson JN; Pound MC; Sharrock A; Youings SA; Dennis NR; McKechnie N; Linehan P; Morton NE; Jacobs PA 《Human molecular genetics》1997,6(2):173-184
Factors involved in the stability of trinucleotide repeats during
transmission were studied in 139 families in which a full mutation,
premutation or intermediate allele at either FRAXA or FRAXE was
segregating. The transmission of alleles at FRAXA, FRAXE and four
microsatellite loci were recorded for all individuals. Instability within
the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for
FRAXE) was extremely rare; only one example was observed, an increased in
size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in
the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were
unstably transmitted. Instability was more frequent for FRAXA intermediate
alleles that had a tract of pure CGG greater than 37 although instability
only occurred in two of 13 such transmissions: the changes observed were
limited to only one or two repeats. Premutation FRAXA alleles over 100
repeats expanded to a full mutation during female transmission in 100% of
cases, in agreement with other published series. There was no clear
correlation between haplotype and probability of expansion of FRAXA
premutations. Instability at FRAXA or FRAXE was more often observed in
conjunction with a second instability at an independent locus suggesting
genomic instability as a possible mechanism by which at least some FRAXA
and FRAXE mutations arise.
相似文献
22.
J Davies B Srinivasan PA Brennan 《Annals of the Royal College of Surgeons of England》2021,103(1):e42
Lipomas are common benign tumours that can occur in most parts of the body. Lipomas arising from the deep temporal fat pad, found between the two layers of the deep temporal fascia, are rare, however; there has been only one documented case report to our knowledge. We describe a second case arising from the temporal fat pad in a patient treated at our unit, having previously reported the first one, and discuss the relevant anatomy and management. 相似文献
23.
Joshua R Lewis Trudy Voortman John PA Ioannidis 《Journal of bone and mineral research》2021,36(2):219-226
A healthy diet is essential to attain genetically determined peak bone mass and maintain optimal skeletal health across the adult lifespan. Despite the importance of nutrition for bone health, many of the nutritional requirements of the skeleton across the lifespan remain underexplored, poorly understood, or controversial. With increasingly aging populations, combined with rapidly changing diets and lifestyles globally, one anticipates large increases in the prevalence of osteoporosis and incidence of osteoporotic fractures. Robust, transparent, and reproducible nutrition research is a cornerstone for developing reliable public health recommendations to prevent osteoporosis and osteoporotic fractures. However, nutrition research is often criticized or ignored by healthcare professionals due to the overemphasis of weak science, conflicting, confusing or implausible findings, industry interests, common misconceptions, and strong opinions. Conversely, spurious research findings are often overemphasized or misconstrued by the media or prominent figures especially via social media, potentially leading to confusion and a lack of trust by the general public. Recently, reforms of the broader discipline of nutrition science have been suggested and promoted, leading to new tools and recommendations to attempt to address these issues. In this perspective, we provide a brief overview of what has been achieved in the field on nutrition and bone health, focusing on osteoporosis and osteoporotic fractures. We discuss what we view as some of the challenges, including inherent difficulties in assessing diet and its change, disentangling complex interactions between dietary components and between diet and other factors, selection of bone-related outcomes for nutrition studies, obtaining evidence with more unbiased designs, and perhaps most importantly, ensuring the trust of the public and healthcare professionals. This perspective also provides specific recommendations and highlights new developments and future opportunities for scientists studying nutrition and bone health. © 2021 American Society for Bone and Mineral Research (ASBMR). 相似文献
24.
Inhibition of mouse mast cell proliferation and proinflammatory mediator release by benzodiazepines. 总被引:3,自引:0,他引:3
Mast cell (MC) activation may occur in vitro and in vivo following stimulation with various immunologic or nonimmunologic agents. Such activation leads to the release of several biological mediators, including vasoactive amines, nitric oxide and cytokines, which account for the adverse effects observed during allergic reactions. While high affinity binding sites for benzodiazepines (BZDs) have been reported on MC, the effects of the ligation of these receptors on the proliferation of, and the mediator release from, these cells are poorly documented. In the present work, we have examined the effects of midazolam and of diazepam on the proliferation of mucosal (MMC)-like and of serosal (CTMC)-like mouse MC. In addition, we have studied the effects of these BZDs on beta-hexosaminidase, TNF-alpha and nitrite release induced from mouse mast cells through IgE receptor activation. We demonstrated that each of the two BZDs studied inhibited the proliferation of MMC- and CTMC-like elements in a dose-dependent fashion (10 to 100 microM). Furthermore, the BZDs inhibited the IgE-mediated release of beta-hexosaminidase, TNF-alpha and nitrites from MMC- or CTMC-like cells. Altogether, these data provide new insights into the pharmacological regulation of MC activation and may lead to the discovery of new and potent antiallergic compounds. 相似文献
25.
J. L. Moreau M. J. Royer-Morrot R. J. Royer A. Lozniewski G. Trackoen P. Delavault 《European journal of clinical pharmacology》1996,49(5):401-405
Penetration of pefloxacin into the uroepithelium was studied in 20 patients (10 men and 10 women) receiving a single oral dose of 800 mg. Samples of serum, urine, and uroepithelium were taken 1.8 h (mean) after the dose. Pefloxacin and its active metabolite, norfloxacin, were assayed by liquid chromatography, and the microbiologically active compounds were quantified by a microbiological assay. Both procedures were correlated (r>0.7); nevertheless, slight differences detected in concentrations depended on the levels of norfloxacin achieved in the biological samples. The serum and tissue concentrations were higher than the concentration of bactericide (4 g·ml–1), except in one case. The uroepithelium concentration of pefloxacin was proportional to the serum concentration (r=0.79). The urinary concentrations ranged from 1.2 g·ml–1 to 82.4 g·ml–1. The mean norfloxacin/pefloxacin ratios were 3% in serum, 8% in uroepithelium, and 44% in urine. The mean uroepithelium/serum concentration ratios were 1 for pefloxacin and 2.3 for norfloxacin. This result shows that, at a time close to that of the maximum concentration, there is good penetration of pefloxacin and norfloxacin into the uroepithelium. 相似文献
26.
27.
28.
目的探讨瘦素质量浓度与早期静脉营养及生长发育的关系。方法新疆医科大学第一
附属医院新生儿科于2005 01—2006 02,将收治的86例早产适于胎龄儿用随机数字表法分为观察组(早期微量喂养同时辅助胃肠外营养组)45
例和对照组(单纯早期微量喂养组)47例,分别测定脐血及第7天血清瘦素质量浓度,同时监测营养状况和生长发育指标,并作对比分析。结果
(1)观察组与对照组脐血瘦素质量浓度分别为(4.6±3.7)ng/mL、(4.8±2.2)ng/mL,生后第7天两组瘦素质量浓度分别为(4.3±2.2)ng/mL、(3.1
±1.7)ng/mL。对照组第7天血清瘦素质量浓度明显低于脐血(P<0.05),而观察组其差异无统计学意义(P>0.05)。(2)脐血瘦素质量浓度与出生体
重、胎龄成正相关(r=0.56、r=0.67)。(3)观察组第7天热卡及蛋白质摄入量、血清瘦素质量浓度、皮褶厚度变化值与对照组相比,差异有统计
学意义(P<0.05)。结论对早产儿应尽早喂养,同时需要胃肠外营养作为肠内营养的补充。瘦素可作为新生儿营养效果判定的实验室指标之一。 相似文献
29.
30.
Heather R. Royer Catherine Cerf 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》2009,38(6):686-692
Objective: To determine whether young women differentiate between the terms sexually transmitted disease and sexually transmitted infection and if they do whether their reasons are consistent with those of health care providers.
Design: Secondary analysis of cross-sectional, survey data.
Setting: Four women's health clinics and one university classroom.
Patient/Participants: Three hundred and two women aged 18 to 24.
Methods: The women completed a survey that measured beliefs about seven sexually transmitted diseases, a demographic and sexually transmitted disease health information questionnaire, and a single item assessing whether the terms sexually transmitted disease and sexually transmitted infection were interchangeable.
Results: Fifty-seven percent ( n =155) responded that sexually transmitted disease and sexually transmitted infection do not mean the same thing, 28% ( n =76) responded that sexually transmitted disease and sexually transmitted infection mean the same thing, and 15% ( n =42) responded they do not know. Beliefs about sexually transmitted disease stigma and symptoms were not related to sexually transmitted disease terminology; beliefs about curability were related but not in the hypothesized direction.
Conclusions: A majority of the young women do differentiate between the terms sexually transmitted disease and sexually transmitted infection; however, the rationale for doing so is not consistent with the rationale used by health care providers. Professionals should clarify their use of the terms sexually transmitted disease and sexually transmitted infection when talking with patients as a means to improve health communication and subsequently improve sexually transmitted disease health care. 相似文献
Design: Secondary analysis of cross-sectional, survey data.
Setting: Four women's health clinics and one university classroom.
Patient/Participants: Three hundred and two women aged 18 to 24.
Methods: The women completed a survey that measured beliefs about seven sexually transmitted diseases, a demographic and sexually transmitted disease health information questionnaire, and a single item assessing whether the terms sexually transmitted disease and sexually transmitted infection were interchangeable.
Results: Fifty-seven percent ( n =155) responded that sexually transmitted disease and sexually transmitted infection do not mean the same thing, 28% ( n =76) responded that sexually transmitted disease and sexually transmitted infection mean the same thing, and 15% ( n =42) responded they do not know. Beliefs about sexually transmitted disease stigma and symptoms were not related to sexually transmitted disease terminology; beliefs about curability were related but not in the hypothesized direction.
Conclusions: A majority of the young women do differentiate between the terms sexually transmitted disease and sexually transmitted infection; however, the rationale for doing so is not consistent with the rationale used by health care providers. Professionals should clarify their use of the terms sexually transmitted disease and sexually transmitted infection when talking with patients as a means to improve health communication and subsequently improve sexually transmitted disease health care. 相似文献