全文获取类型
收费全文 | 3021篇 |
免费 | 220篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 35篇 |
儿科学 | 88篇 |
妇产科学 | 56篇 |
基础医学 | 562篇 |
口腔科学 | 63篇 |
临床医学 | 341篇 |
内科学 | 550篇 |
皮肤病学 | 76篇 |
神经病学 | 345篇 |
特种医学 | 78篇 |
外科学 | 205篇 |
综合类 | 18篇 |
一般理论 | 1篇 |
预防医学 | 321篇 |
眼科学 | 59篇 |
药学 | 225篇 |
中国医学 | 5篇 |
肿瘤学 | 219篇 |
出版年
2024年 | 4篇 |
2023年 | 30篇 |
2022年 | 50篇 |
2021年 | 90篇 |
2020年 | 55篇 |
2019年 | 71篇 |
2018年 | 101篇 |
2017年 | 73篇 |
2016年 | 83篇 |
2015年 | 118篇 |
2014年 | 109篇 |
2013年 | 160篇 |
2012年 | 264篇 |
2011年 | 264篇 |
2010年 | 128篇 |
2009年 | 103篇 |
2008年 | 218篇 |
2007年 | 191篇 |
2006年 | 198篇 |
2005年 | 204篇 |
2004年 | 183篇 |
2003年 | 155篇 |
2002年 | 149篇 |
2001年 | 23篇 |
2000年 | 20篇 |
1999年 | 28篇 |
1998年 | 30篇 |
1997年 | 18篇 |
1996年 | 12篇 |
1995年 | 17篇 |
1994年 | 13篇 |
1993年 | 11篇 |
1992年 | 5篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 5篇 |
1985年 | 9篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1974年 | 3篇 |
1972年 | 3篇 |
1968年 | 2篇 |
1965年 | 3篇 |
排序方式: 共有3247条查询结果,搜索用时 46 毫秒
31.
Janine Reichenbach Andrea Jarisch Saima Khan Miriam H?mberg Christina Bez Stefan Zielen 《Annals of allergy, asthma & immunology》2002,89(5):498-502
BACKGROUND: High levels of serum eosinophil cationic protein (sECP) as a marker of eosinophilic airway inflammation have been described as a predictor of childhood asthma. Bronchial hyperreactivity (BHR) appears to be secondary to the release of inflammatory mediators. OBJECTIVE: We investigated the possible correlation between eosinophilic inflammation and BHR in 72 infants with recurrent wheezing. METHODS: To determine bronchial reactivity, lung function measurements with methacholine challenge were performed in 72 infants, aged 12 to 30 months, and the degree of BHR to methacholine was compared with sECP values. Patients were grouped according to low (group 1, <10 microg/L, n = 22), medium (group 2, 10 to 20 microg/L, n = 23), and high (group 3, >20 microg/L, n = 27) sECP values. RESULTS: In group 1, sECP levels ranged from 3.1 to 9.9 microg/L, mean 6.6 microg/L +/- standard deviation [SD] 2.3, in group 2, from 10.3 to 19.8 microg/L, mean 14.3 microg/L +/- SD 2.8, and in group 3 from 23.0 to 66.7 microg/L, mean 34.5 microg/L +/- SD 9.5. Distribution of provocative methacholine concentration among groups was as follows: group 1, 30 to 976 microg, mean 350.9 microg +/- SD 258.3; group 2, 36 to 752 microg, mean 340.7 microg +/- SD 226.3; group 3, 41 to 848 microg, mean 301.3 microg +/- SD 189.8 methacholine. CONCLUSION: There was no significant correlation between sECP levels and bronchial reactivity in all groups (r = -0.076, P = 0.6), indicating that these parameters reflect two independent pathogenic mechanisms in the etiology of childhood asthma. 相似文献
32.
Beth B Matsushita F Mounier S Shiggins R Papon B Kernbaum S 《Bulletin de la Societe de pathologie exotique (1990)》1998,91(5 PT 1-2):464-466
More and more foreign tourists are being treated at the American Hospital of Paris. The main reasons for this are the presence of a 24 hour medical and dental emergency service, in addition to the availability of MRI, CT scan and comprehensive laboratory facilities. The hospital is multidisciplinary, where short stay hospitalizations are the rule. English is the second most commonly used language. There is a permanent Japanese language service for Japanese patients. Qualitative data is presented concerning the management of patients according to specialty and nationality. American and Japanese patients admitted to the hospital in 1997 are surveyed according to their mean age, reasons for admission and appropriate specialty as well as mean length of stay noted. The greatest number of hospitalizations in decreasing order and according to nationality are as follows: American, Japanese, Moroccan Egyptian and Saudi Arabian. The consultations and hospitalizations of Japanese patients between 1990 and 1997 are compared. 相似文献
33.
Deemer E Bertocci G Pierce MC Aguel F Janosky J Vogeley E 《Medical engineering & physics》2005,27(1):31-39
INTRODUCTION: Falls are a major cause of morbidity and mortality in children, but are also reported falsely in child abuse. Therefore, it is of interest to understand those factors which may lead to a higher likelihood of injury in a feet-first freefall. METHODS: We used laboratory freefall experiments and a 3-year-old Hybrid III anthropomorphic test dummy (ATD) to assess head and femur injury risk. Wet and dry linoleum impact surfaces were used from three fall heights: 22, 35 and 47 in. RESULTS: For a given fall height, dry surfaces were associated with higher head injury criteria (HIC) values than wet surfaces. Changes in fall height 22-47 in. did not significantly affect HIC values for falls onto either surface. Generally, compressive and bending femur loading increased significantly for wet as compared to dry linoleum. CONCLUSIONS: In simulated feet first freefall experiments up to 47 in. using a 3-year-old test dummy, a low risk of contact type head injury and femur fracture was found. However, both fall height and surface conditions influenced femur loading and head injury measures. Future efforts should explore the risk of head injury associated with angular acceleration in freefalls. 相似文献
34.
Use of R-Mix Fresh Cells has been shown to be a rapid and sensitive method for the detection and identification of respiratory viruses. We prospectively evaluated the impact of incorporation of R-Mix shell vials on the sensitivity and time to detection of seven respiratory viruses recovered in a comprehensive culture during the course of an entire respiratory season in a high-volume clinical laboratory. In this study, R-Mix shell vials were used as part of the culture of 3803 respiratory specimens. A total of 428 respiratory viruses were recovered. Staining of R-Mix vials after overnight incubation allowed initial detection of 274 of 279 influenza viruses, 33 of 38 parainfluenza viruses, 35 of 51 adenoviruses, and 52 of 60 respiratory syncytial viruses (RSVs). The time to reporting of all positive cultures after in-lab specimen receipt was 2.9 days on average and those initially detected in R-Mix cells were reported in 2.3 days on average. A combination of direct fluorescent-antibody (DFA) staining and virus culture was performed on a subset of 711 respiratory specimens. Of 152 viruses identified, 57 were observed only with DFA testing (55 RSV and 2 influenza A viruses) and 31 were recovered only in cell culture. After overnight incubation, R-Mix cells detected 87.1% of respiratory viruses not observed by DFA testing and 96.9% of viruses positive by both methods. The sensitivities of DFA testing and R-Mix cells for identification of influenza viruses were 70.5% and 96.7%, respectively. The R-Mix method detected influenza virus in 18 samples that were negative by DFA testing. 相似文献
35.
C. Crouzet H. Fournier X. Papon N. Hentati P. Cronier Ph. Mercier 《Surgical and radiologic anatomy : SRA》1998,20(4):273-278
Summary The findings from 12 dissections of previously injected facial masks, 8 dissections of the face following intrarterial injection of a red solution of Latex Neoprene, and a corrosion cast specimen allowed us to study the arterial supply of the lips. The arterial supply of the upper lip arises mainly from the superior labial arteries, but also from the subseptal arteries and from the subalar arteries. There is a figure of 8 shaped anastomotic system between these arteries lying on the upper lip. The arterial supply of the lower lip arises from the inferior labial arteries and from branches of the mental artery. A constant inferior labial arterial network was shown at the level of the lower lip arising in a fifth of cases from a T-shaped inferior labial artery. All these recent anatomic findings help us to improve our understanding of plastic surgery of the lips.
Vascularisation artérielle des lèvres
Résumé Douze dissections de masques faciaux préalablement injectés à la gélatine minium, huit dissections de face après injection artérielle par une solution de latex néoprène rouge, et une injectioncorrosion a permis l'étude de la vascularisation artérielle labiale. La lèvre supérieure reçoit sa vascularisation artérielle des artères labiales supérieures principalement, mais aussi des artères sous-narinaires branches des artères faciales, et des artères de la sous-cloison. Il existe un système d'anastomose fréquent entre les trois artères décrivant un aspect de 8 de chiffre couché au niveau de la lèvre supérieure. La lèvre inférieure est vascularisée par les artères labiales inférieures et par des branches de l'artère mentonnière ; il existe de manière constante au niveau de la lèvre inférieure une arche artérielle labiale inférieure provenant une fois sur cinq d'une artère labiales inférieure en T unique. Toute ces données anatomiques récentes permettent d'envisager dans de meilleures conditions la chirurgie réparatrice des lèvres.相似文献
36.
Receptors for immunoglobulin isotypes (FcR) on murine T cells. I. Multiple FcR expression on T lymphocytes and hybridoma T cell clones 总被引:1,自引:0,他引:1
Marc Daëron Junji Yodoi Catherine Nauport-Sauts Janine Moncuit Wolf H. Fridman 《European journal of immunology》1985,15(7):662-667
T cell receptors for the Fc portion of the various isotypes of mouse immunoglobulins (FcR) were examined by rosette formation, using as indicator cells erythrocytes coated with monoclonal antibodies of all known isotypes of serum immunoglobulins. Three populations of mouse T cells were studied: normal thymocytes, activated T cells (ATC), generated by educating thymocytes in lethally irradiated allogeneic hosts, and hybridoma T cells, derived from somatic hybridization of ATC with the FcR-negative thymoma BW.5147. We found that many different FcR could be distinguished by their specificity for a single isotype or for a combination of several isotypes; ATC and hybridoma T cells expressed several such receptors that, at least in cloned cells, could be demonstrated to be borne by individual cells; hybridoma T cells of independent origin bore indistinguishable receptors whereas ATC expressed markedly different FcR and upon overnight incubation at 37 degrees C, immunoglobulins were found to bind onto the cell surface, even though no corresponding constitutive FcR was detected. The same was observed with hybridoma T cells and with thymocytes. It follows that a single T cell can express several FcR. Altogether, these FcR are capable of binding all known isotypes of serum immunoglobulins. They differ from one T cell to another. 相似文献
37.
Paul?D.?WatersEmail author Margaret?L.?Delbridge Janine?E.?Deakin Nisrine?El-Mogharbel Patrick?J.?Kirby Denise?R.?Carvalho-Silva Jennifer?A.?Marshall?Graves 《Chromosome research》2005,13(4):401-410
Mammalian sex chromosomes evolved from an ancient autosomal pair. Mapping of human X- and Y-borne genes in distantly related mammals and non-mammalian vertebrates has proved valuable to help deduce the evolution of this unique part of the genome. The platypus, a monotreme mammal distantly related to eutherians and marsupials, has an extraordinary sex chromosome system comprising five X and five Y chromosomes that form a translocation chain at male meiosis. The largest X chromosome (X1), which lies at one end of the chain, has considerable homology to the human X. Using comparative mapping and the emerging chicken database, we demonstrate that part of the therian X chromosome, previously thought to be conserved across all mammals, was lost from the platypus X1 to an autosome. This region included genes flanking the XIST locus, and also genes with Y-linked homologues that are important to male reproduction in therians. Since these genes lie on the X in marsupials and eutherians, and also on the homologous region of chicken chromosome 4, this represents a loss from the monotreme X rather than an additional evolutionary stratum of the human X. 相似文献
38.
39.
Ashford Kristin McCubbin Andrea Barnett Janine Blair Lisa M. Lei Feitong Bush Heather Breland Alison 《Maternal and child health journal》2021,25(8):1175-1181
Maternal and Child Health Journal - In the US, approximately 8% of pregnant women smoke, and 5–11.9% currently use ENDS products. The health effects of ENDS use are debated; however, most... 相似文献
40.
Janine Jewanraj Sinaye Ngcapu Farzana Osman Veron Ramsuran Maryam Fish Andile Mtshali Ravesh Singh Leila E Mansoor Salim S Abdool Karim Quarraisha Abdool Karim JoAnn S Passmore Lenine J P Liebenberg 《Journal of the International AIDS Society》2021,24(6)
IntroductionSemen induces mucosal changes in the female reproductive tract to improve pregnancy outcomes. Since semen‐induced alterations are likely short‐lived and genital inflammation is linked to HIV acquisition in women, we investigated the contribution of recent semen exposure on biomarkers of genital inflammation in women at high HIV risk and the persistence of these associations.MethodsWe assessed stored genital specimens from 152 HIV‐negative KwaZulu‐Natal women who participated in the CAPRISA 008 trial between November 2012 and October 2014. During the two‐year study period, 651 vaginal specimens were collected biannually (mean five samples per woman). Cervicovaginal lavage (CVL) was screened for prostate‐specific antigen (PSA) by ELISA, whereas Y‐chromosome DNA (YcDNA) detection and quantification were conducted by RT‐PCR, representing semen exposure within 48 hours (PSA+YcDNA+) and semen exposure within three to fifteen days (PSA−YcDNA+). Soluble protein concentrations were measured in CVLs by multiplexed ELISA. T‐cell frequencies were assessed in cytobrushes by flow‐cytometry, and vulvovaginal swabs were used to detect common vaginal microbes by PCR. Linear mixed models adjusting for factors associated with genital inflammation and HIV risk were used to assess the impact of semen exposure on biomarkers of inflammation over multiple visits.ResultsHere, 19% (125/651) of CVLs were PSA+YcDNA+, 14% (93/651) were PSA−YcDNA+ and 67% (433/651) were PSA−YcDNA−. Semen exposure was associated with how often women saw their partners, the frequency of vaginal sex in the past month, HSV‐2 antibody detection, current gonorrhoea infection and Nugent Score. Both PSA detection (PSA+YcDNA+) and higher cervicovaginal YcDNA concentrations predicted increases in several cytokines, barrier‐related proteins (MMP‐2, TIMP‐1 and TIMP‐4) and activated CD4+CCR5+HLA‐DR+ T cells (β = 0.050; CI 0.001 to 0.098; p = 0.046) and CD4+HLA‐DR+ T cells (β = 0.177; CI 0.016 to 0.339; p = 0.032) respectively. PSA detection was specifically associated with raised pro‐inflammatory cytokines (including IL‐6, TNF‐α, IP‐10 and RANTES), and with the detection of BVAB2 (OR = 1.755; CI 1.116 to 2.760; p = 0.015), P. bivia (OR = 1.886; CI 1.102 to 3.228; p = 0.021) and Gardnerella vaginalis (OR = 1.815; CI 1.093 to 3.015; p = 0.021).ConclusionsMore recent semen exposure was associated with raised levels of inflammatory biomarkers and the detection of BV‐associated microbes, which declined by three to fifteen days of post‐exposure. Although transient, semen‐induced alterations may have implications for HIV susceptibility in women. 相似文献