全文获取类型
收费全文 | 3655篇 |
免费 | 138篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 59篇 |
妇产科学 | 38篇 |
基础医学 | 492篇 |
口腔科学 | 22篇 |
临床医学 | 742篇 |
内科学 | 811篇 |
皮肤病学 | 19篇 |
神经病学 | 303篇 |
特种医学 | 102篇 |
外科学 | 466篇 |
综合类 | 17篇 |
预防医学 | 176篇 |
眼科学 | 63篇 |
药学 | 258篇 |
中国医学 | 7篇 |
肿瘤学 | 237篇 |
出版年
2023年 | 11篇 |
2022年 | 20篇 |
2021年 | 35篇 |
2020年 | 17篇 |
2019年 | 30篇 |
2018年 | 45篇 |
2017年 | 45篇 |
2016年 | 32篇 |
2015年 | 60篇 |
2014年 | 94篇 |
2013年 | 118篇 |
2012年 | 241篇 |
2011年 | 278篇 |
2010年 | 142篇 |
2009年 | 158篇 |
2008年 | 272篇 |
2007年 | 287篇 |
2006年 | 277篇 |
2005年 | 297篇 |
2004年 | 281篇 |
2003年 | 305篇 |
2002年 | 250篇 |
2001年 | 31篇 |
2000年 | 34篇 |
1999年 | 37篇 |
1998年 | 46篇 |
1997年 | 35篇 |
1996年 | 33篇 |
1995年 | 44篇 |
1994年 | 34篇 |
1993年 | 22篇 |
1992年 | 16篇 |
1991年 | 24篇 |
1990年 | 11篇 |
1989年 | 11篇 |
1988年 | 14篇 |
1987年 | 11篇 |
1986年 | 10篇 |
1985年 | 7篇 |
1984年 | 17篇 |
1983年 | 8篇 |
1982年 | 14篇 |
1981年 | 11篇 |
1980年 | 11篇 |
1979年 | 13篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1976年 | 3篇 |
1974年 | 4篇 |
1973年 | 4篇 |
排序方式: 共有3826条查询结果,搜索用时 31 毫秒
21.
Multiplex PCR targeting tpi (triose phosphate isomerase), tcdA (Toxin A), and tcdB (Toxin B) genes for toxigenic culture of Clostridium difficile 总被引:1,自引:0,他引:1 下载免费PDF全文
Lemee L Dhalluin A Testelin S Mattrat MA Maillard K Lemeland JF Pons JL 《Journal of clinical microbiology》2004,42(12):5710-5714
A multiplex PCR toxigenic culture approach was designed for simultaneous identification and toxigenic type characterization of Clostridium difficile isolates. Three pairs of primers were designed for the amplification of (i) a species-specific internal fragment of the tpi (triose phosphate isomerase) gene, (ii) an internal fragment of the tcdB (toxin B) gene, and (iii) an internal fragment of the tcdA (toxin A) gene allowing distinction between toxin A-positive, toxin B-positive (A+B+) strains and toxin A-negative, toxin B-positive (A−B+) variant strains. The reliability of the multiplex PCR was established by using a panel of 72 C. difficile strains including A+B+, A−B−, and A−B+ toxigenic types and 11 other Clostridium species type strains. The multiplex PCR assay was then included in a toxigenic culture approach for the detection, identification, and toxigenic type characterization of C. difficile in 1,343 consecutive human and animal stool samples. Overall, 111 (15.4%) of 721 human samples were positive for C. difficile; 67 (60.4%) of these samples contained A+B+ toxigenic isolates, and none of them contained A−B+ variant strains. Fifty (8%) of 622 animal samples contained C. difficile strains, which were toxigenic in 27 (54%) cases, including 1 A−B+ variant isolate. Eighty of the 721 human stool samples (37 positive and 43 negative for C. difficile culture) were comparatively tested by Premier Toxins A&B (Meridian Bioscience) and Triage C. difficile Panel (Biosite) immunoassays, the results of which were found concordant with toxigenic culture for 82.5 and 92.5% of the samples, respectively. The multiplex PCR toxigenic culture scheme described here allows combined diagnosis and toxigenic type characterization for human and animal C. difficile intestinal infections. 相似文献
22.
Nicole Bruneau Frédérique Bonnet-Brilhault Marie Gomot Jean-Louis Adrien Catherine Barthélémy 《International journal of psychophysiology》2003,51(1):17-25
The purpose of the present study was to investigate the relations between late auditory evoked potentials (AEPs) recorded at temporal sites (the N1c wave or Tb) and verbal and non-verbal abilities in children with autism. The study was performed in 26 mentally retarded children with autism (AUT) aged 4-8 years (mean age +/- S.E.M. = 71 +/- 2 months; mean verbal and non-verbal developmental quotient +/- S.E.M. = 36 +/- 4 and 48 +/- 3). The stimuli used were 750 Hz tone bursts of 200 ms duration delivered binaurally at different intensity levels (50, 60, 70, 80 dB SPL) with 3-5 s interstimulus intervals. Temporal AEPs were first compared to those of a group of 16 normal children (NOR) in the same age range (mean age +/- S.E.M. = 69 +/- 3 months). We then focused on the AUT group and considered relations between temporal AEPs and the severity of disorders of verbal and non-verbal communication assessed using a behavior rating scale. AEPs recorded on left and right temporal sites were of smaller amplitude in the AUT group than in the NOR group. Increasing intensity-related amplitude was observed on both sides in NOR and only on the right side in AUT. The lack of intensity effect on the left side resulted in a particular pattern of asymmetry at the highest level of intensity (80 dB SPL) with greater N1c amplitude on the right than on the left side (the reverse was found in the NOR group). Electro-clinical correlations indicated that the greater the amplitude of the right temporal N1c responses, the higher the verbal and non-verbal communication abilities. This suggests a developmental reorganization of left-right hemisphere functions in autism, with preferential activation of the right hemisphere for functions usually allocated to the left hemisphere, particularly those involving the secondary auditory areas situated on the lateral surface of the superior temporal gyrus where the N1c/Tb wave is generated. 相似文献
23.
24.
Stéphanie Chasseigneaux Stéphane Haïk Isabelle Laffont-Proust Olivier De Marco Martine Lenne Jean-Philippe Brandel Jean-Jacques Hauw Jean-Louis Laplanche Katell Peoc’h 《Neuroscience letters》2006
A valine to isoleucine mutation at residue 180 was identified in a French patient with Creutzfeldt-Jakob disease (CJD). The mutation is located in the close vicinity of one of the two N-glycosylation sites of the cellular prion protein (PrPC). Western blot analysis revealed accumulation in the brain of the pathogenic proteinase K-resistant PrP (PrPSc) isoform with the notable absence of the diglycosylated band. The mutant protein expressed in CHO cells was correctly glycosylated, suggesting that the atypical glycosylation pattern of PrPSc was not due to the mutation at position 180. These results suggest that the diglycosylated form of the mutant PrP180I prevents its conversion into the pathogenic mutant form PrPSc180I, supporting a central role of N-linked glycan chains in the PrP conversion process. 相似文献
25.
Complete Primary Sequences of Two λ Immunoglobulin Light Chains in Myelomas with Nonamyloid (Randall-Type) Light Chain Deposition Disease 下载免费PDF全文
Catherine Decourt Guy Touchard Jean-Louis Preudhomme Ruben Vidal Hlne Beaufils Marie-Claude Diemert Michel Cogn 《The American journal of pathology》1998,153(1):313-318
We herein report on the first two primary sequences (BOU and RAC) of monoclonal light chains of the λ type responsible for nonamyloid λ light chain deposition disease. Both patients were affected with severe forms of myeloma complicated with renal failure. The pathological presentation typically featured Congo red-negative deposits along tubular basement membranes but differed somewhat from the typical “Randall-type” κ light chain deposition disease: they lacked the prominent glomerulosclerosis pattern often featuring nonamyloid κ deposits and were associated with cylinders or myeloma casts. Both protein sequences were deduced from those of the corresponding complementary DNAs in the bone marrow plasma cells. For each chain, products of three independent amplifications by polymerase chain reaction were sequenced and found to be identical. BOU and RAC λ mRNAs had a normal overall structure consisting of Vλ2 segments rearranged to Jλ2Cλ2 but displayed a number of unusual features within their primary sequences. These substitutions are likely responsible for changes in light chain conformation that promote their aggregation and deposition along renal tubule basement membranes. 相似文献
26.
A heterogeneous set of FMR1 proteins is widely distributed in mouse tissues and is modulated in cell culture 总被引:8,自引:7,他引:8
27.
Benjamin Pelletier Audrey Perrin Noémie Assoun Camille Plaquet Nathalie Oreal Laetitia Gaulme Adeline Bouzereau Jean-Louis Labernardière Mélanie Ligouis Vincent Dioszeghy Sophie Wavrin Katie Matthews Fabrice Porcheray Hugh A. Sampson Pierre-Louis Hervé 《Allergy》2021,76(4):1213-1222
Background
The prevalence of tree nut allergy has increased worldwide, and cashew has become one of the most common food allergens. More critically, cashew allergy is frequently associated with severe anaphylaxis. Despite the high medical need, no approved treatment is available and strict avoidance and preparedness for prompt treatment of allergic reactions are considered dual standard of care. In the meantime, Phase III study results suggest investigational epicutaneous immunotherapy (EPIT) may be a relevant and safe treatment for peanut allergy and may improve the quality of life for many peanut allergic children.Objective
We aimed to evaluate the capacity of EPIT to provide protection against cashew-induced anaphylaxis in a relevant mouse model.Methods
The efficacy of EPIT was evaluated by applying patches containing cashew allergens to cashew-sensitized mice. As negative control, sham mice received patches containing excipient. Following treatment, mice were challenged orally to cashew and anaphylactic symptoms, as well as plasmatic levels of mast-cell proteases (mMCP)-1/7, were quantified.Results
Of 16 weeks of EPIT significantly protects against anaphylaxis by promoting a faster recovery of challenged mice. This protection was characterized by a significant reduction of temperature drop and clinical symptoms, 60 minutes after challenge. This was associated with a decrease in mast-cell reactivity as attested by the reduction of mMCP-1/7 in plasma, suggesting that EPIT specifically decrease IgE-mediated anaphylaxis.Conclusion
We demonstrate that EPIT markedly reduced IgE-mediated allergic reactions in a mouse model of cashew allergy, which suggests that EPIT may be a relevant approach to treating cashew allergy.28.
Patricia Chastagner Jean-Louis Moreau Yannick Jacques Toshiyuki Tanaka Masayuki Miyasaka Motonari Kondo Kazuo Sugamura Jacques Thze 《European journal of immunology》1996,26(1):201-206
An interleukin (IL)-4 dependant mouse T cell clone 8.2 derived from an IL-2-dependent T cell line was characterized. As measured by flow cytometric analysis and Northern blotting, it expresses IL-2 receptor β (IL-2Rβ) and γ (IL-2Rγ) chains, but has lost expression of IL-2 receptor α chain (IL-2Rα). To investigate the properties of the mouse IL-2Rβγ complex and the role of IL-2Rα gene expression, this clone was further studied. T cell clone 8.2 has lost the capacity to bind 125I-labeled human IL-2 under experimental conditions able to detect intermediate-affinity IL-2R in human cells. Mouse IL-2 is unable to block the binding of mAb TMβ1 to 8.2 cells. Under the same experimental conditions, mouse IL-2 blocks the binding of TMβ1 to C30-1 cells expressing the IL-2αβγ complex. Since TMβ1 recognizes an epitope related to the IL-2 binding site of IL-2Rβ, these results can be taken as a demonstration that mouse IL-2Rβγ does not bind mouse IL-2. Furthermore, T cell clone 8.2 does not proliferate in response to recombinant mouse or human IL-2. On the other hand, T cell transfectant lines expressing heterospecific receptors made of the human IL-2Rβ and mouse IL-2Rγ chains bind 125I-labeled human IL-2 and proliferate in response to IL-2. This establishes the difference between mouse and human IL-2Rβ chains. Transfection of T cell clone 8.2 with human IL-2Rα genes restores their capacity to proliferate in response to IL-2. In addition, all transfectants grown in IL-2 express the endogeneous mouse IL-2Rα chain. When grown in IL-4, the endogeneous mouse IL-2Rα gene remains silent in all these transfectants. These results show that, contrary to the human, the mouse does not express an intermediate-affinity IL-2R. Expression of the IL-2Rα gene is therefore required for the formation of the functional IL-2R in mice. 相似文献
29.
Safety of cryopreservation straws for human gametes or embryos: a study with human immunodeficiency virus-1 under cryopreservation conditions 总被引:3,自引:0,他引:3
30.
Filali-Zegzouti Y Abdelmelek H Rouanet JL Cottet-Emard JM Pequignot JM Barré H 《Pflügers Archiv : European journal of physiology》2000,441(2-3):275-280
Physiological studies have shown that glucagon is a potential mediator of nonshivering thermogenesis (NST) in birds. The present work was undertaken in order to investigate whether the observed thermogenesis results from a direct action of glucagon on avian thermoregulatory mechanisms or in fact requires the participation of other agents such as catecholamines. Our experiments were performed using cold-acclimated (CA) ducklings which developed muscle NST. A comparison was made with thermoneutral (TN) ducklings of the same age. Our principal results showed that: (1) at ambient temperature (25 degrees C), circulating norepinephrine (NE) was markedly decreased in CA ducklings (-42%), while circulating epinephrine (E) did not undergo any consistent change; (2) in CA and TN ducklings, an intraperitoneal injection of glucagon (360 microg x kg(-1)) was followed after 10 min by prominent lipolysis and a large increase in circulating NE (4- to 6-fold) and E (14- to 17-fold), which was sustained for at least 1 h. The elevation of circulating NE was less pronounced in CA ducklings. The thermogenic action of glucagon in birds is probably indirect and involves at least the mobilization of lipids and sympatho-adrenal stimulation. The changes in peripheral noradrenergic activity during cold acclimation could be associated with adaptive changes leading to NST. 相似文献