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51.
Rabot S Szylit O Nugon-Baudon L Meslin JC Vaissade P Popot F Viso M 《Digestive diseases and sciences》2000,45(9):1687-1695
The purpose of this work was to assess the influence of microgravity on several endogenous and microbial parameters of digestive physiology. On the occasion of two Spacelab Life Sciences missions, SLS-1 (a 9-day space flight) and SLS-2 (a 14-day space flight), Sprague-Dawley rats flown aboard the US space shuttle were compared to age-matched ground-based controls. In both flights, exposure to microgravity modified cecal fermentation: concentration and profile of short-chain fatty acids were altered, whereas urea and ammonia remained unchanged. Only in SLS-1 was there an induction of intestinal glutathione-S-transferase. Additional analyses in SLS-2 showed a decrease of hepatic CYP450 and of colonic goblet cells containing neutral mucin. After a postflight recovery period equal to the mission length, only modifications of the hepatic and intestinal xenobiotic metabolizing enzymes still persisted. These findings should help to predict the alterations of digestive physiology and detoxification potential likely to occur in astronauts. Their possible influence on health is discussed. 相似文献
52.
Mayer A Ploix C Orgiazzi J Desbos A Moreira A Vidal H Monier JC Bienvenu J Fabien N 《The Journal of clinical endocrinology and metabolism》2004,89(9):4484-4488
We investigated the presence of autoantibodies (aAbs) directed against the parathyroid gland in 17 patients with spontaneous isolated acquired hypoparathyroidism. Fourteen patients with acquired hypoparathyroidism (AH) associated with type I or II autoimmune polyendocrinopathy syndrome were also tested in comparison with a control group of 68 subjects without AH, including patients with other autoimmune diseases and healthy blood donors. aAbs against parathyroid tissue were screened using an indirect immunofluorescence technique on primate parathyroid tissue and human parathyroid adenoma. aAbs against the calcium-sensing receptor (CaSR) were analyzed using an immunoblotting assay with the recombinant extracellular domain of the human CaSR as antigen. Seven of the 31 patients with AH were positive for CaSR aAbs. Five of the positive sera were obtained from the group with isolated AH. The two other positive sera were from patients with autoimmune polyendocrinopathy syndrome. The sensitivity of the immunoblotting technique was higher than that of both the radioimmunological test using the extracellular domain of the CaSR and the indirect immunofluorescence technique. There were no positive sera in the control group. In conclusion, using an immunoblotting assay, we demonstrate the presence of CaSR aAbs in about one third of the patients with isolated AH, pointing out the value of detecting such aAbs to assess the autoimmune origin of the disease. 相似文献
53.
Rheumatoid flat foot and deformity of the first ray 总被引:4,自引:0,他引:4
Bouysset M Tebib J Noel E Tavernier T Miossec P Vianey JC Duivon JP Bonnin M Nemoz C Jalby J 《The Journal of rheumatology》2002,29(5):903-905
OBJECTIVE: To study the relationship between flat foot and forefoot deformities in rheumatoid arthritis (RA) in order to improve understanding of the progression of deformity and thus provide more appropriate treatment. METHODS: Anteroposterior and lateral weight-bearing radiographs were obtained of 308 feet of patients with RA and 202 feet of patients with neck pain (control feet). RESULTS: In women with RA, we observed with disease duration an increased frequency of flat foot that was correlated with first ray deformity (chiefly metatarsus primus adductus) and severe stages of disability. Flat foot increased very markedly after 3-4 years of disease duration. In control women, flat feet were more frequent after the age of 50 years. CONCLUSION: In RA the inflammatory and mechanical factors leading to foot deformity must receive early medical treatment to avoid progressive hindfoot deformities that lead to disability. 相似文献
54.
Canard JM Debette-Gratien M Dumas R Escourrou J Gay G Giovannini M Greff M Grimaud JC Helbert T Marchetti B Lapuelle J Napoleon B Palazzo L Ponchon T Rey JF Sautereau D;la Société Française d'Endoscopie Digestive 《Gastroentérologie clinique et biologique》2005,29(1):17-22
AIM: The aim of this study was to evaluate the practice of colonoscopy and sigmoidoscopy in France in 2000. METHODS: A prospective study was conducted in November 2000 using questionnaires sent to all gastroenterologists practicing in France (N=2858) who were asked to reply to items concerning colonoscopies and sigmoidoscopies performed on two workdays chosen in advance. The response rate was 32.8%. Data were extrapolated to establish estimates for the entire year. RESULTS: An estimated 894000 colonoscopies and 115320 sigmoidoscopies were performed in 2000. Single-use material was used in 22.1% of the procedures. Indications for endoscopy were mainly hematochezia (21.6%), gastrointestinal symptoms (35%) and surveillance of patients with a history of previous polypectomy (15%). Colorectal cancer screening was the indication for 20% of colonoscopies. Abnormal findings were reported for 54.8% of the endoscopies (polyps for 287218 procedures and cancer for 32799). Failure was noted in 4.9% of colonoscopies. The complication rate was 0.48%. Most polyps were adenomas (64.4%) or hyperplasic polyps (28.1%). The overall estimated number of colonoscopies with polypectomy was 224133. CONCLUSION: In 2000 there was an increased rate of colonoscopy for colorectal cancer screening (20%) but an overall decrease (2.5%) in the total number of colonoscopies compared to 1999. Abnormal findings were disclosed by 54.8% of the procedures. Extrapolation from these data indicates that colonoscopic screening enabled the diagnosis of 32799 colorectal cancers. 相似文献
55.
56.
Impairment of death-inducing signalling complex formation in CD95-resistant human primary lymphoma B cells 总被引:3,自引:0,他引:3
Lajmanovich A Irisarri M Molens JP Pasquier MA Sotto JJ Bensa JC Leroux D Plumas J 《British journal of haematology》2004,124(6):746-753
Multiple mechanisms exist by which tumour cells can escape CD95-mediated apoptosis. Previous studies by our laboratory have shown that primary B cells from non-Hodgkin's Lymphoma (B-NHL) were resistant to CD95-induced cell death. In the current study, we have analysed the mechanisms underlying CD95 resistance in primary human lymphoma B cells. We report that FADD (FAS-associated death domain protein) and caspase-8 were constitutively expressed in lymphoma B cells and that the CD95 pathway was blocked upstream to caspase-8 activation. However, caspase-8 was processed and functional after treatment with staurosporine (STS). We found that the expression levels of FLICE (FADD-like interleukin-1 beta-converting enzyme)-Inhibitory Protein (c-FLIP) and Bcl-2-related proteins were heterogeneous in B-NHL cells and were not related to CD95 resistance. Finally, we report the absence of a CD95-induced signalling complex [death-inducing signalling complex (DISC)] in lymphoma B cells, with no FADD and caspase-8 recruitment to CD95 receptor. In contrast, DISC formation was observed in CD95-resistant non-tumoural (NT) B cells. Therefore, we propose that the absence of DISC formation in primary lymphoma B cells may contribute to protect these cells from CD95-induced apoptosis. 相似文献
57.
58.
Evidence for hydrophobic region within heavy chains of mouse B lymphocyte membrane-bound IgM 总被引:5,自引:0,他引:5 下载免费PDF全文
Pierre Vassalli Rachel Tedghi Barbara Lisowska-Bernstein Alan Tartakoff Jean-Claude Jaton 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(11):5515-5519
The gel filtration behavior, in the presence of detergents, of membrane-bound IgM from normal mouse spleen B lymphocytes was compared to that of secretory IgM from mouse plasma cells. The proteins were labeled either by surface radioiodination or biosynthetically with radioactive amino acids. Cell lysates were fractionated on calibrated Sepharose 6B columns in the presence of the detergents Nonidet P-40 or deoxycholate. Eluted fractions were immunoprecipitated and the reduced or unreduced precipitates were analyzed by sodium dodecyl sulfate gel electrophoresis followed by radioautography. Surface (125)I-labeled 8S IgM exhibited a gel filtration pattern in Nonidet P-40 corresponding to much higher apparent molecular weight than that of secretory 8S IgM, a difference that almost disappeared when gel filtration was performed in the presence of deoxycholate, which forms much smaller micelles than does Nonidet P-40. Biosynthetically labeled lymphocytes contain two types of IgM molecules differing in their gel filtration behavior and fate: one identical to secretory 8S IgM of plasma cells and secreted in the medium during chase periods, and the other identical to surface (125)I-labeled IgM and remaining cell-associated. Because the surface-bound 8S IgM was not found to be associated with other labeled molecules, it is likely that the detergent-binding behavior of surface IgM is due to a hydrophobic segment carried by these Ig molecules. That lymphocytes synthesize two types of mu chains was also shown by the use of tunicamycin, an inhibitor of glycosylation. In its presence, two unglycosylated mu chains were observed: one identical in size to that made by tunicamycin-treated plasma cells, and the second slightly larger. Gel filtration in Nonidet P-40 of the cell lysates of tunicamycin-treated lymphocytes showed that the nonsecretory 8S IgM contains this second type of mu chains, whereas the IgM molecules of the secretory type contain plasma cell-like mu chains. It is suggested that membrane IgM mu chains contain a hydrophobic segment which is responsible for its association to the membrane. 相似文献
59.
60.
Antoine Frigaux Joëlle Lighezzolo-Alnot Jean-Claude Maleval Renaud Evrard 《L'évolution Psychiatrique》2021,86(1):e1-e24
ObjectivesData on the prevalence of Autism Spectrum Disorder (ASD) reveal several clinical evolutions inducing new psychiatric definitions and diagnostic practices. Thus, autism has shifted from being a rare syndrome with severe clinical forms to a new paradigm: the paradigm of “ordinary” or “invisible” autism, in terms of the frequency and the intensity of the disorders. These changes incorporate new populations into our conception of autism, with new phenotypes that pose theoretical and clinical challenges to clinicians. In response, we propose the hypothesis — based on psychoanalytic theories of psychic structures — of an “ordinary autism” as a definition of a non-prototypical autistic psychic functioning that falls outside the DSM diagnostic framework. This idea seems to provide us new theoretical references that nourish our practices as well as fundamental research.MethodFirst, we will review the nosographic mutations of the DSM-5 and their implications for non-prototypical psychic modes of functioning of autistic people that may not be contained within the autism spectrum's blurry boundaries — especially for the adult population without intellectual delay and in the case of complicated differential diagnosis for clinical and societal reasons. Next, we will discuss the definition of “ordinary” or “invisible” autism in a psychoanalytic structural model, as a possible epistemological orientation for identifying and designing practice with the clinical heterogeneity of autism outside the boundaries of psychiatric ASD.ResultsThe autistic population targeted by the DSM-5 criteria is different from that previously defined by DSM-IV. This leads to two consequences: on the one hand, autistic modes of functioning are not limited to individuals who have been diagnosed with Autism Spectrum Disorders as defined by the DSM-5; thus individuals with autism do not have access to the diagnosis of ASD or are given other diagnoses. The alternative diagnoses proposed by the DSM-5 that attempt to correct this diagnostic exclusion — such as Social (Pragmatic) Communication Disorder — are unsatisfactory. Therefore, there is an entire segment of the autistic population that has subclinical, non-prototypic autistic manifestations or more subtle phenomena discernible in the broader autistic phenotype or sub-threshold autism spectrum that does not have access to the ASD diagnosis and raises differential diagnostic issues. On the other hand, it appears that the autism spectrum brings together extremely different entities and false positives such as schizophrenia and schizophrenic spectrum personality disorders under one diagnostic rubric. Then, the differential problem appears central: both at the theoretical level and in diagnostic practices. The recognition of these limits should encourage us to promote research and clinical applications on this subject. One solution that we envisage is to be found in an extension of Maleval's structural psychoanalytical model: we propose the notion of “ordinary autism” — an echo of ordinary psychosis — to define attenuated or compensated non-prototypical autistic phenotypes, increasingly frequent and with fewer “extraordinary” phenomenological expressions than the classic cases of autism which now call into question the relationship between the normal and the pathological.Discussion“Ordinary autism” seems to offer clinicians the opportunity to formalize the new contemporary and extensive clinical reality of autism. This term situates itself within a theoretical model whose current and future developments might help us respond to clinical and diagnostic issues, but also to therapeutic and societal ones. We propose to continue on the path of the operationalization of these theoretical models in order to identify autistic structural constants that could be found throughout the “ordinary” clinic of autism and could serve as differentiating tools for diagnosis as well as a support in developing and refining therapeutic practices.ConclusionWe conclude that there is an urgent need to conceive of “ordinary autism” to provide us with reference points to respond to new clinical issues, but also to reintroduce respect for the autistic person in his or her subjectivity to the center of our therapeutic practices. 相似文献