全文获取类型
收费全文 | 4160篇 |
免费 | 303篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 124篇 |
妇产科学 | 79篇 |
基础医学 | 603篇 |
口腔科学 | 70篇 |
临床医学 | 468篇 |
内科学 | 805篇 |
皮肤病学 | 117篇 |
神经病学 | 468篇 |
特种医学 | 131篇 |
外科学 | 391篇 |
综合类 | 22篇 |
一般理论 | 1篇 |
预防医学 | 393篇 |
眼科学 | 114篇 |
药学 | 245篇 |
中国医学 | 11篇 |
肿瘤学 | 420篇 |
出版年
2024年 | 9篇 |
2023年 | 47篇 |
2022年 | 93篇 |
2021年 | 143篇 |
2020年 | 91篇 |
2019年 | 143篇 |
2018年 | 122篇 |
2017年 | 105篇 |
2016年 | 116篇 |
2015年 | 114篇 |
2014年 | 152篇 |
2013年 | 220篇 |
2012年 | 319篇 |
2011年 | 326篇 |
2010年 | 163篇 |
2009年 | 148篇 |
2008年 | 280篇 |
2007年 | 225篇 |
2006年 | 255篇 |
2005年 | 266篇 |
2004年 | 204篇 |
2003年 | 198篇 |
2002年 | 194篇 |
2001年 | 39篇 |
2000年 | 27篇 |
1999年 | 50篇 |
1998年 | 42篇 |
1997年 | 34篇 |
1996年 | 30篇 |
1995年 | 27篇 |
1994年 | 18篇 |
1993年 | 13篇 |
1992年 | 20篇 |
1991年 | 7篇 |
1990年 | 9篇 |
1989年 | 8篇 |
1988年 | 16篇 |
1987年 | 12篇 |
1986年 | 12篇 |
1985年 | 10篇 |
1984年 | 15篇 |
1983年 | 10篇 |
1982年 | 11篇 |
1981年 | 15篇 |
1980年 | 14篇 |
1979年 | 10篇 |
1978年 | 7篇 |
1977年 | 7篇 |
1971年 | 6篇 |
1958年 | 5篇 |
排序方式: 共有4484条查询结果,搜索用时 0 毫秒
1.
Marital status and cohabitation during pregnancy: relationship with social conditions, antenatal care and pregnancy outcome in France 总被引:1,自引:0,他引:1
Summary. A survey of a representative sample of 5508 births in France in 1981 permitted the study of social characteristics of pregnant women, the medical care they received during their pregnancy and their pregnancy outcome, as a function of their marital status and whether or not they lived with the father of the child. Unmarried women living with the father (n = 412) like unmarried women living alone (n = 171), were more often younger, having their first baby and had a lower educational level than did married women living with the father (n = 4590). However, among the unmarried women, those living alone were in a more unfavourable position than those living with the father; in particular, they were more often less than 20 years old, had the minimum educational level required and were unemployed. Both groups of unmarried women had a higher preterm delivery rate than did married women, even after taking other risk factors into account in a logistic regression. The odds ratios (95% confidence interval) for pre-term delivery among unmarried mothers living without the father was 1.9 (1.0–3.4) and that for the unmarried cohabiting with the father was 1.6 (1.0–2.4). Thus, to fully appreciate the perinatal risks and medical needs during pregnancy, both the marital and cohabitational status of the women should be considered. 相似文献
2.
3.
Nephrotic syndrome in a mother and her infant: relationship with cytomegalovirus infection 总被引:1,自引:0,他引:1
Marisa Giani Alberto Edefonti Beatrice Damiani Giuseppina Marra Daniela Colombo Giovanni Banfi Emilio Rivolta Erich H. Strøm Michael Mihatsch 《Pediatric nephrology (Berlin, Germany)》1996,10(1):73-75
This case report describes infantile nephrotic syndrome (NS) in a baby girl with a clinically severe cytomegalovirus (CMV) infection. Culture of the baby's urine was positive for CMV and IgM anti-CMV antibodies were detected. After an unsuccessful course of corticosteroids, gancyclovir treatment was started and a remission of cutaneous, pulmonary, and renal symptoms was achieved. As the mother also developed NS at the end of pregnancy, a common etiology could be postulated, although there were no signs of recent CMV infection in the mother, only anti-CMV IgG. The relationship between CMV infection and glomerular disease is still unclear: NS may represent another manifestation of CMV disease. 相似文献
4.
D C Des Jarlais J Wenston S R Friedman J L Sotheran R Maslansky M Marmor S Yancovitz S Beatrice 《American journal of public health》1992,82(11):1531-1533
The Centers for Disease Control (CDC) has proposed revising the AIDS surveillance definition to include any HIV-seropositive person with a CD4 cell count of less than 200 cells per microliter. Based on a study of persons receiving treatment for HIV infection, this new definition would lead to an estimated 50% increase in the number of persons recognized as living with AIDS. Among 440 HIV-seropositive research subjects recruited from drug treatment programs and through street outreach in New York City, 59 met this definition, yet only 25% of those had been reported to the New York City AIDS registry. The new definition, if combined with HIV and T-cell testing at drug treatment and street outreach programs, could thus yield very large increases in the number of injecting drug users meeting the new surveillance definition of AIDS. 相似文献
5.
Actinomycetous infections typically involve either the head and neck or the extremities following a traumatic implantation.
Classic clinical associations are draining sinus tracts. This case report describes the pathologic and MR findings of a relatively
acute mycetomatous process involving the soft tissues. Pathologic findings in this case included an occasional granule composed
of gram positive, thin branching elements. These and other findings were consistent with actinomycetes bacterium infection.
The discussion centers around the use of MR, both with and without gadolinium, in evaluating this type of granulomatous infection.
Infiltration of the adjacent subcutaneous tissues was easier to appreciate on both the T1-weighted images without gadolinium
and the T1-weighted images with gadolinium when compared to the T2-weighted images. Signal characteristics as described in
this case report may suggest a granulomatous process. 相似文献
6.
Zvi Laron Jenny Frenkel lrit Gil-Ad Beatrice Klinger Ernesto Lubin Patrick Wuthrich François Boutignon Vincent Lengerts Romano Deghenghi 《Clinical endocrinology》1994,41(4):539-541
OBJECTIVE Hexarelin is a new synthetic growth hormone releasing peptide. We have tested the efficacy of intranasal (i.n.) administration of hexarelin to stimulate plasma GH and have compared this to the intravenous (i.v.) administration of the peptide. PATIENTS Ten children with familial short stature (FSS) aged 5·5-15·5 years and two known GH deficient patients aged 24 and 28 years without GH treatment. METHODS All 12 subjects were submitted to i.v. (1 μg/kg) and i.n. (20 μg/kg) hexarelin tests with a one-week interval between tests. Blood samples for GH, TSH, fT4 and T3 were obtained at 0, 15, 30, 60, 90 and 120 minutes. The hormone determinations were made by standard radio-immunoassays (RIA). RESULTS Both the i.n. and i.v. administration of hexarelin induced a large GH response, the mean (±SD) being 72·2± 35·5 mU/l for the i.n. test and 79·6 ± 53·0 mU/l for the i.v. test. The peak GH in the i.v. test occurred at 15–30 minutes and in the i.n. test between 30 and 60 minutes. The GH deficient patients showed no GH response In either test. Plasma TSH decreased in the FSS children from a mean (±SD) of 1.0 ± 0·26 to 0·64±0 2 mU/l (P<0 005) during the i.n. test and from 1·0±0·3 to 0·7±0·3mU/l (P> 0 05) during the I.v. test. In the isolated GH deficient patient, plasma TSH decreased from 1·06±0·38 mU/l to 0·86±0·17 during the i.v. test and from 1·60±0·01 to 1·11±0·06mU/l during the i.n. test. There were no significant changes in plasma fT4 or T3 in any of the tests. CONCLUSIONS The synthetic hexapeptide hexarelin is a potent pituitary GH stimulator when administered intra-nasally. The GH response was similar to that observed after intravenous hexarelin. Simultaneously, there was a significant decrease in plasma TSH but the concentrations remained in the normal range. These findings appear to be of theoretical and practical relevance to the investigation and management of short children. 相似文献
7.
8.
Internalization of sst2, sst3, and sst5 receptors: effects of somatostatin agonists and antagonists. 总被引:4,自引:0,他引:4
Renzo Cescato Stefan Schulz Beatrice Waser Véronique Eltschinger Jean E Rivier Hans-Jürgen Wester Michael Culler Mihaela Ginj Qisheng Liu Agnes Schonbrunn Jean Claude Reubi 《Journal of nuclear medicine》2006,47(3):502-511
The uptake of radiolabeled somatostatin analogs by tumor cells through receptor-mediated internalization is a critical process for the in vivo targeting of tumoral somatostatin receptors. In the present study, the somatostatin receptor internalization induced by a variety of somatostatin analogs was measured with new immunocytochemical methods that allow characterization of trafficking of the somatostatin receptor subtype 2 (sst2), somatostatin receptor subtype 3 (sst3), and somatostatin receptor subtype 5 (sst5) in vitro at the protein level. METHODS: Human embryonic kidney 293 (HEK293) cells expressing the sst2, sst3, or the sst5 were used in a morphologic immunocytochemical internalization assay using specific sst2, sst3 and sst5 antibodies to qualitatively and quantitatively determine the capability of somatostatin agonists or antagonists to induce somatostatin receptor internalization. In addition, the internalization properties of a selection of these agonists have been compared and quantified in sst2-expressing CHO-K1 cells using an ELISA. RESULTS: Agonists with a high sst2-binding affinity were able to induce sst2 internalization in the HEK293 and CHO-K1 cell lines. New sst2 agonists, such as Y-DOTA-TATE, Y-DOTA-NOC, Lu-DOTA-BOC-ATE (where DOTA is 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid; TATE is [Tyr3, Thr8]-octreotide; NOC is [1-NaI3]-octreotide; and BOC-ATE is [BzThi3, Thr8]-octreotide), iodinated sugar-containing octreotide analogs, or BIM-23244 were considerably more potent in internalizing sst2 than was DTPA-octreotide (where DTPA is diethylenetriaminepentaacetic acid). Similarly, compounds with high sst3 affinity such as KE108 were able to induce sst3 internalization. In sst2- or sst3-expressing cell lines, agonist-induced receptor internalization was efficiently abolished by sst2- or sst3-selective antagonists, respectively. Antagonists alone had no effect on sst2 or sst3 internalization. We also showed that somatostatin-28 and somatostatin-14 can induce sst5 internalization. Unexpectedly, however, potent sst5 agonists such as KE108, BIM-23244, and L-817,818 were not able to induce sst5 internalization under the same conditions. CONCLUSION: Using sensitive and reproducible immunocytochemical methods, the ability of various somatostatin analogs to induce sst2, sst3, and sst5 internalization has been qualitatively and quantitatively determined. Whereas all agonists triggered sst2 and sst3 internalization, sst5 internalization was induced by natural somatostatin peptides but not by synthetic high-affinity sst5 agonists. Such assays will be of considerable help for the future characterization of ligands foreseen for nuclear medicine applications. 相似文献
9.
Dose dependent effects of S-20098, a melatonin agonist,on direction of re-entrainment of rat circadian activity rhythms 总被引:1,自引:0,他引:1
J. R. Redman M. Brown Beatrice Guardiola-Lemaitre P. Delagrange S. M. Armstrong 《Psychopharmacology》1995,119(4):385-390
The chronobiotic properties of melatonin are well documented. For example, following an 8-h phase advance of the light-dark cycle daily injections of melatonin administered at the pre-shift dark onset alter the direction of re-entrainment of rat activity rhythms. Using this 8-h phase advance paradigm, the effects of the melatonin agonist S-20098 (1 mg/kg and 3 mg/kg) on the rat circadian system were compared with those of melatonin. S-20098 altered the direction of reentrainment in the same manner as melatonin. A study using lower doses of S-20098 showed that the effect on direction of re-entrainment was dose-dependent, with 100% of rats responding at a dose of 100 µg/kg. S-20098 may, therefore, have therapeutic potential as a chronobiotic in the treatment of circadian disorders in humans. 相似文献
10.
Paola Sarchielli Andrea Alberti Beatrice Gallai Francesca Coppola Antonio Baldi Ardesio Floridi Virgilio Gallai 《The journal of headache and pain》2002,3(3):129-135
Little has been done to investigate the biochemical basis of chronic daily headache (CDH). Our group has recently demonstrated
an increase in the cerebrospinal fluid (CSF) levels of nerve growth factor (NGF) in CDH patients, supporting the involvement
of this growth factor in the abnormal processing of head pain in this pathological condition. Other members of the neurotrophin
family, especially brain-derived neurotrophic factor (BDNF), have been hypothesized as being involved in the development of
chronic head pain in patients affected by CDH, but so far no data are available on this subject. BDNF, NGF and glutamate levels
were determined in the CSF of 25 patients affected by CDH with a previous history of migraine. These levels were compared
with those of a group of 20 control subjects, for whom the CSF examination and other instrumental investigations excluded
diseases of the central and peripheral nervous systems. Significantly higher levels of BDNF, NGF and glutamate were found
in CDH patients compared with control subjects (p<0.0001, p<0.0002 and p<0.001, respectively). A significant positive correlation emerged between CSF values of BDNF and those of NGF (r=0.61, p<0.001) and glutamate (r=0.44, p<0.025) in CDH patients. No significant differences were detected in BDNF, NGF and glutamate levels between CDH patients with
analgesic overuse and those without. These results support the involvement of BDNF in CDH through the potentiation of glutamatergic
transmission involved in the processing of head pain. The significant correlation between BDNF and NGF levels suggests that
NGF-mediated up-regulation of BDNF in central sites involved in long-term sensitization plays a key role in persistent head
pain in CDH patients.
Correspondence to P. Sarchielli 相似文献