全文获取类型
收费全文 | 12995篇 |
免费 | 748篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 97篇 |
儿科学 | 383篇 |
妇产科学 | 187篇 |
基础医学 | 1606篇 |
口腔科学 | 403篇 |
临床医学 | 1374篇 |
内科学 | 2519篇 |
皮肤病学 | 159篇 |
神经病学 | 1235篇 |
特种医学 | 356篇 |
外科学 | 2172篇 |
综合类 | 101篇 |
一般理论 | 9篇 |
预防医学 | 862篇 |
眼科学 | 305篇 |
药学 | 1030篇 |
中国医学 | 19篇 |
肿瘤学 | 952篇 |
出版年
2023年 | 98篇 |
2022年 | 111篇 |
2021年 | 236篇 |
2020年 | 221篇 |
2019年 | 312篇 |
2018年 | 298篇 |
2017年 | 282篇 |
2016年 | 311篇 |
2015年 | 302篇 |
2014年 | 433篇 |
2013年 | 679篇 |
2012年 | 886篇 |
2011年 | 891篇 |
2010年 | 478篇 |
2009年 | 471篇 |
2008年 | 808篇 |
2007年 | 844篇 |
2006年 | 790篇 |
2005年 | 715篇 |
2004年 | 702篇 |
2003年 | 668篇 |
2002年 | 605篇 |
2001年 | 138篇 |
2000年 | 110篇 |
1999年 | 150篇 |
1998年 | 173篇 |
1997年 | 160篇 |
1996年 | 124篇 |
1995年 | 105篇 |
1994年 | 112篇 |
1993年 | 85篇 |
1992年 | 82篇 |
1991年 | 93篇 |
1990年 | 91篇 |
1989年 | 93篇 |
1988年 | 75篇 |
1987年 | 81篇 |
1986年 | 84篇 |
1985年 | 94篇 |
1984年 | 83篇 |
1983年 | 67篇 |
1982年 | 93篇 |
1981年 | 52篇 |
1980年 | 50篇 |
1979年 | 52篇 |
1978年 | 38篇 |
1977年 | 37篇 |
1976年 | 35篇 |
1974年 | 31篇 |
1973年 | 31篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
151.
Human phase I vaccine trials of 3 recombinant asexual stage malaria antigens with Montanide ISA720 adjuvant 总被引:13,自引:0,他引:13
Allan Saul Gregor Lawrence Anne Smillie Christine M. Rzepczyk Carol Reed Darrin Taylor Karen Anderson Anthony Stowers Richard Kemp Anthony Allworth Robin F. Anders Graham V. Brown David Pye Peter Schoofs David O. Irving Shanny L. Dyer Graeme C. Woodrow William R. S. Briggs Rosemaria Reber Dieter Stürchler 《Vaccine》1999,17(23-24):3145-3159
Two phase I vaccine trials were conducted to test the immunogenicity and safety of a vaccine containing three recombinant malaria antigens from the asexual stage of Plasmodium falciparum. The three antigens are a fragment of MSP1 (190LCS.T3); MSP2 and a portion of RESA and were formulated in Montanide ISA720 adjuvant. These trials investigated the dose response of each antigen for eliciting both antibody and T-cell responses and the immunogenicity of a mixture of the antigens compared with the antigens injected separately. All three antigens elicited both antibody and T-cell responses. Strong T-cell responses were observed with 190LCS.T3 and RESA with stimulation indices exceeding 100 for peripheral blood leucocytes in some individuals. The antibody responses were generally weak. The human antibody responses observed with MSP2 in Montanide ISA720 were not significantly different from those obtained in an earlier trial which used MSP2 with alum as the adjuvant. No antigenic competition was observed: volunteers receiving a mixture of antigens had similar responses to those receiving the three antigens at separate sites. Tenderness and pain at the injection site were common over the first few days following immunization. In some volunteers, especially those receiving the highest doses tested, there was a delayed reaction at the injection site with pain and swelling occurring approximately 10 days after injection. 相似文献
152.
OBJECTIVE: To evaluate the efficacy and safety of intracameral lidocaine in cataract surgery compared to peribulbar anesthesia. DESIGN: A prospective, randomized, controlled study. PARTICIPANTS: A total of 200 consecutive cataract patients (200 eyes) participated. INTERVENTION: Eyes were randomly assigned to two groups: one group received 0.15 ml intracameral 1% unpreserved lidocaine combined with topical anesthesia (oxybuprocaine); the other group received 6 ml prilocaine peribulbar before phacoemulsification with sclerocorneal tunnel incision. MAIN OUTCOME MEASURES: Duration of surgery was measured; implicit time and amplitudes of the b-waves of the photopic electroretinogram (ERG) potentials (single-flash ERG and the 30-Hz flicker ERG) were recorded; frequencies of intraoperative problems, complications, intraoperative, and postoperative pain were evaluated. RESULTS: After lidocaine anesthesia combined with topical anesthesia, similar complications were found, longer operation time (P < 0.001), and significantly better visual acuity immediately after surgery (P < 0.001). The ERG amplitudes were not significantly reduced after 0.15-ml intracameral lidocaine half an hour after surgery (P > 0.05). CONCLUSION: Intracameral lidocaine 1% combined with topical anesthesia can be recommended as an alternative procedure to peribulbar anesthesia in cataract surgery with corneoscleral tunnel incision. 相似文献
153.
Accommodative facility training with a long term follow up in a sample of school aged children showing accommodative dysfunction 总被引:3,自引:0,他引:3
Sterner B Abrahamsson M Sjostrom A 《Documenta ophthalmologica. Advances in ophthalmology》1999,99(1):93-101
The primary aim of this project was to study the effect of flip lens-training on the accommodative function in a group of
children with accommodative dysfunction and subjective symptoms such as asthenopia, headache, blurred vision, and avoidance
of near activity. We also wanted to measure the accommodative facility among the children in comparison with a control group.
Another aim of the study was whether flip lens-training increased accommodative facility, and to find out if it also had a
positive effect on their asthenopia and related problems also in long term. Following the training period the accommodative
facility and accommodative function significantly increased and two years after finishing the training period no child had
regained any subjective symptoms and the objective findings were almost the same as at the end of facility training period.
These results suggest that accommodative facility training is an efficient method built on loss of symptoms among children
with accommodative infacility.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
154.
Norbert Anders Karl-Titus Hoffmann Norbert Hosten Tony Walkow Roland Felix Christian Hartmann 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,96(10):658-662
Dacryocystorhinostomy is still the standard procedure complete stenosis of the nasolacrimal duct. New methods try to preserve the natural lacrimal pathway. Song implanted in 1995 a nasolacrimal polyurethane stent through the nasolacrimal duct. The results and complications of this new method are described in this prospective study. METHODS: Thirty consecutive patients with complete obstruction of the nasolacrimal duct or lacrimal sac were included in the study. The stenosis was localized by dacryocystography. The ages ranged from 22 to 87 years (mean, 58.9 +/- 16 years). Dacryocystography was performed immediately, 4 weeks and 8 months after the procedure to verify the position and patency of the stent. RESULTS: Twenty-five short (35 mm) and 5 long (45 mm) stents were implanted. Twenty-four of 30 patients after 4 weeks and 9 of 10 patients after 8 months had reduced or no complaints. In 1 patient the stent was obstructed. Forceful irrigation with saline solution permitted recanalization. In 1 patient the stent had moved into the upper canaliculus. Because of irritation of the canaliculus it had to be pulled out after 2 months. CONCLUSION: The follow-up is still too short to recommend stent implantation as a real alternative to dacryocystorhinostomy. The main advantages are that the procedure is faster, no incision is necessary, and the local anesthesia is easier. The disadvantage is the need for X-ray examination. 相似文献
155.
156.
Jan Lycke Bo Svennerholm Elisabeth Hjelmquist Lars Frisén Gaby Badr Mats Andersson Anders Vahlne Oluf Andersen 《Journal of neurology》1996,243(3):214-224
Acyclovir treatment was used in a randomized, double-blind, placebo-controlled clinical trial with parallel groups to test the hypothesis that herpes virus infections are involved in the pathogenesis of multiple sclerosis (MS). Sixty patients with the relapsing-remitting form of MS were randomized to either oral treatment with 800 mg acyclovir or placebo tablets three times daily for 2 years. The clinical effect was investigated by an extensive test battery consisting of neurological examinations, neuro-ophthalmological and neuropsychological tests, and evoked potentials. Results were based on intent-to-treat data and the primary outcome measure was the exacerbation rate. In the acyclovir group (n = 30), 62 exacerbations were recorded during the treatment period, yielding an annual exacerbation rate of 1.03. The placebo group (n = 30) had 94 exacerbations and an annual exacerbation rate of 1.57. Thus, 34% fewer exacerbations were encountered during acyclovir treatment. This difference in exacerbation rate between the treatment groups was not significant (P = 0.083). However, this trend to a lower disease activity in acyclovir-treated patients was supported in subsequent data analysis. If the patients were grouped according to exacerbation frequencies, i.e. into low (0–2), medium (3–5) and high (6–8) rate groups, the difference between acyclovir and placebo treatment was significant (P = 0.017). Moreover, in a subgroup of the population with a duration of the disease of at least 2 years providing an exacerbation rate base-line before entry, individual differences in exacerbation rates were compared between the 2-year pre-study period and the study period in acyclovir-treated (n = 19) and placebo (n = 20) patients and acyclovir-treated patients showed a significant reduction of exacerbations (P = 0.024). Otherwise, neurological parameters were essentially unaffected by acyclovir treatment and there were no convincing signs of reduced neurological deterioration in the acyclovir group. This study indicates that acyclovir treatment might inhibit the triggering of MS exacerbations and thus suggests that acyclovir-susceptible viruses might be involved in the pathogenesis of MS. This possibility warrants further investigation. 相似文献
157.
Maternal risk of breast cancer following multiple births: a nationwide study in Sweden 总被引:2,自引:0,他引:2
Mats Lambe Chung-cheng Hsieh Shirng-wern Tsaih Anders Ekbom Hans-Olov Adami Dimitrios Trichopoulos 《Cancer causes & control : CCC》1996,7(5):533-538
The association between multiple births and subsequent maternal breast cancer risk was explored in a nested case-control study in Sweden encompassing 19,368 parous women with breast cancer diagnosed up to age 65 years, and 100,459 parous controls. Among cases and controls, there were 329 and 2,031 women, respectively, with a history of at least one live multiple birth. Compared with singleton mothers, breast cancer risk was 12 percent lower (odds ratio=0.088, 95 percent confidence interval=0.78–0.99) in women who had had a multiple birth. After stratification for age at diagnosis, evidence of a significant inverse association was found only in women aged 54 years or younger. Birth order of the multiple pregnancy had no apparent risk-modifying effect. Age at earliest multiple birth was unrelated to breast cancer risk. The inverse association between twinning and breast cancer risk may reflect protective physiological features of twin pregnancies. Further research is needed to investigate the role, if any, of in creased levels of steroid hormone-binding globulins in mothers of twins and the proposed inhibitory effects of human chorionic gonadotropin and -fetoprotein, both of which are increased during multiple gestations, on breast carcinogenesis. Breast feeding patterns in mothers of twins also may modify their risk of developing breast cancer.Ambors are with the Department of Cancer Epidemiology (Drs Lambe Ekbom, Adami) and Department of Social Medicine (Lambe), University Hospital, Uppsala, Sweden: Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA (Drs Hsieb, Tsilib, Adami, Ekbom, Trichopoulos); UMASS Cancer Center, Worcester, MA, USA (Dr Hsieb). Address correspondece to Dr Lambe, Department of Cancer Epidemiology, University Hospital, S-751 85 Uppsala, Sweden. This project is funded by grants from the Swedish Cencer Societv. the Swedish Societv of Medicine. and the Wahlmarks Fund at Uppsala City Council. 相似文献
158.
159.
Multiple-dose pharmacokinetics of epirubicin at four different dose levels: studies in patients with metastatic breast cancer 总被引:2,自引:0,他引:2
Preben Jakobsen Eva Steiness Lars Bastholt Mads Dalmark Anders Lorenzen Dorthe Petersen Susanne B. Gjedde Erik Sandberg Carsten Rose Ole S. Nielsen Henning T. Mouridsen Anders Jakobsen 《Cancer chemotherapy and pharmacology》1991,28(1):63-68
Summary Pharmacokinetic analysis of epirubicin and its metabolites epirubicinol and 7-deoxy-13-dihydro-epirubicinol aglycone during the first and the fourth courses of treatment was performed in 78 patients with metastatic breast cancer. The patients were treated every 3 weeks with epirubicin given as 10-min i.v. infusions at four different dose levels: 40, 60, 90 and 135 mg/m2. In most cases (76 of 78 cases), plasma concentration-time curves fitted to a three-compartmental pharmacokinetic model. The terminal half-life of epirubicin was independent of dose and duration of treatment. Large interindividual differences were demonstrated (meant
1/2, 21.6±7.9 h; range, 10.6–69 h;n=110). In two subjects, extremely long half-lives and high serum bilirubin concentrations indicated impaired liver function. No correlation was found between the half-life and levels of liver alanine aminotransferase (ALAT) or serum creatinine. The metabolite epirubicinol appeared quickly after epirubicin administration and its half-lives were shorter than that of the parent compound (meant
1/2, 18.1±4.8 h; range, 8.2–38.4 h;n=105).Formation of the aglycone metabolite was delayed and the half-life of this metabolite was shorter than that of epirubicin (meant
1/2, 13±4.6 h; range, 2.7–29 h;n=104). The AUC of epirubicin and the total AUC (drug and metabolites) were linearly proportional to the dose, with the former value constituting two-thirds of the latter. A correlation was found between AUC and the plasma concentration of epirubicin at two time points (2 and 24 h after administration). The proposed model was AUC=9.44×c
2+62.5×c
24+157.7 (r=0.953).This work was supported by the Lundbeck Foundation, the Michaelsen Foundation and Farmitalia Carlo Erba Ltd. 相似文献
160.
Testosterone has previously been used as a model compound for the determination of unstirred water layer thickness in the CACO-2 transport model. We have found, however, that testosterone is metabolized during in vitro transport across the CACO-2 cell monolayers. This suggests that testosterone is not an ideal model substance. Testosterone is metabolized to androstenedione, indicating the formation of 17--hydroxysteroid dehydrogenase by differentiated CACO-2 cells. No reverse metabolism is observed, thus androstenedione is considered superior to testosterone for determination of unstirred water layer thickness in the CACO-2 system. Permeability coefficients for testosterone and androstenedione obtained under identical transport conditions were 66 (±7) * 10 –6 (n = 26) and 84 (±7) * 10–6 (n = 9) cm/sec, respectively. The unstirred water layer thicknesses at different agitation rates are determined for the CACO-2 transport model used in our laboratory utilizing androstenedione as a model compound. The system is capable of controlling the water layer thickness from about 200 to 1000 µm. 相似文献