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51.
Rozen P  Samuel Z  Shomrat R  Legum C 《Gut》1999,45(6):829-833
BACKGROUND: The phenotypic spectrum of familial adenomatous polyposis (FAP) varies from the classic appearance of hundreds of adenomatous colonic polyps in the young adult and early onset colorectal cancer, to the occurrence of sparse adenomas in the older adult, "attenuated" FAP, due to mutations at the 5' or 3' ends of the APC gene. AIMS: To investigate marked intrafamilial phenotypic variation occurring in a family with an APC gene mutation in exon 9. PATIENTS: An extended kindred of 22 people of whom 16 had colorectal neoplasia and/or were APC mutation carriers. RESULTS: Phenotypic manifestation varied from classic FAP to a complete lack of clinical or endoscopic, or bioptic disease in five people in three different generations. This occurred in four of them over two generations, in spite of having a confirmed 11 bp insertion causing a frame shift and stop codon (363) in exon 9 of the APC gene. CONCLUSIONS: At present, it is assumed that in this family there is alternative splicing of the APC gene, and/or unidentified modifying genetic factors. The family illustrates the importance of genetic testing in evaluating carrier status and not just clinical examination. This clinical observation also high- lights the dilemma in recognising the possible contribution of low penetrance germline APC mutations to what has been considered "sporadic" colorectal neoplasia.  相似文献   
52.
Cancer remains the topmost disorder of the mankind and number of cases is unceasingly growing at unprecedented rates. Although the synthetic anti-cancer compounds still hold the largest market in the modern treatment of cancer, natural agents have always been tried and tested for potential anti-cancer properties. Thymoquinone (TQ), a monoterpene and main ingredient in the essential oil of Nigella sativa L. has got very eminent rankings in the traditional systems of medicine for its anti-cancer pharmacological properties. In this review we summarized the diverse aspects of TQ including its chemistry, biosynthesis, sources and pharmacological properties with a major concern being attributed to its anti-cancer efficacies. The role of TQ in different aspects involved in the pathogenesis of cancer like inflammation, angiogenesis, apoptosis, cell cycle regulation, proliferation, invasion and migration have been described. The mechanism of action of TQ in different cancer types has been briefly accounted. Other safety and toxicological aspects and some combination therapies involving TQ have also been touched. A detailed literature search was carried out using various online search engines like google scholar and pubmed regarding the available research and review accounts on thymoquinone upto may 2019. All the articles reporting significant addition to the activities of thymoquinone were selected. Additional information was acquired from ethno botanical literature focusing on thymoquinone. The compound has been the centre of attention for a long time period and researched regularly in quite considerable numbers for its various physicochemical, medicinal, biological and pharmacological perspectives. Thymoquinone is studied for various chemical and pharmacological activities and demonstrated promising anti-cancer potential. The reviewed reports confirmed the strong anti-cancer efficacy of thymoquinone. Further in-vitro and in-vivo research is strongly warranted regarding the complete exploration of thymoquinone in ethnopharmacological context.  相似文献   
53.
Components of high molecular-weight (PI) obtained from Ascaris suum extract down-regulate the Th1/Th2-related immune responses induced by ovalbumin (OVA)-immunization in mice. Furthermore, the PI down-modulates the ability of dendritic cells (DCs) to activate T lymphocytes by an IL-10-mediated mechanism. Here, we evaluated the role of toll like receptors 2 and 4 (TLR2 and 4) in the modulatory effect of PI on OVA-specific immune response and the PI interference on DC full activation. An inhibition of OVA-specific cellular and humoral responses were observed in wild type (WT) or in deficient in TLR2 (TLR2−/−) or 4 (TLR4−/−) mice immunized with OVA plus PI when compared with OVA-immunized mice. Low expression of class II MHC, CD40, CD80 and CD86 molecules was observed in lymph node (LN) cells from WT, TLR2−/− or TLR4−/− mice immunized with OVA plus PI compared with OVA-primed cells. We also verified that PI was able to modulate the activation of DCs derived from bone marrow of WT, TLR2−/− or TLR4−/− mice induced in vitro by agonists of TLRs, as observed by a decreased expression of class II MHC and costimulatory molecules and by low secretion of pro-inflammatory cytokines. Its effect was accompanied by IL-10 synthesis. In this sense, the modulatory effect of PI on specific-immune response and DC activation is independent of TLR2 or TLR4.  相似文献   
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55.
Although many patients with SLE also have allergies, the immunological events triggering the onset and progression of the clinical manifestations of SLE by allergens have yet to be clarified. A total of three autoantigens, phosphoglycerate kinase 1 (PGK-1), triosephosphate isomerase (TIM) and enolase were identified by autologous serum in B cell lysate derived from HDM allergic SLE patients after Der p 2 stimulation. Autoantigen, TRIM-21 expression were also significantly increased in B cells derived from HDM allergic SLE patients. In PBMCs derived from SLE patients, the concentration of anti-PGK-1 was significantly upregulated after Der p 2 stimulation compared to HDM allergic without SLE patients and healthy subjects. Inflammatory related cytokines and chemokines include IL-1β, IL-6, IL-8, CXCL5 could be upregulated after Der p 2 stimulation in PBMCs derived from HDM allergic SLE patients. In conclusion, our data demonstrated that long-term allergen exposure could be a contributing factor in the development of SLE.  相似文献   
56.
Tolerogenic dendritic cells (tDC) constitute a promising therapy for autoimmune diseases, since they can anergize T lymphocytes recognizing self-antigens. Patients with type 1 diabetes mellitus (T1D) have autoreactive T cells against pancreatic islet antigens (insulin, glutamic acid decarboxylase 65 -GAD65-). We aimed to determine the ability of tDC derived from T1D patients to inactivate their insulin- and GAD65-reactive T cells. CD14 + monocytes and CD4 + CD45RA- effector/memory lymphocytes were isolated from 25 patients. Monocyte-derived DC were generated in the absence (control, cDC) or presence of IL-10 and TGF-β1 (tDC), and loaded with insulin or GAD65. DC were cultured with T lymphocytes (primary culture), and cell proliferation and cytokine secretion were determined. These lymphocytes were rechallenged with insulin-, GAD65- or candidin-pulsed cDC (secondary culture) to assess whether tDC rendered T cells hyporesponsive to further stimulation. In the primary cultures, tDC induced significant lower lymphocyte proliferation and IL-2 and IFN-γ secretion than cDC; in contrast, tDC induced higher IL-10 production. Lymphocytes from 60% of patients proliferated specifically against insulin or GAD65 (group 1), whereas 40% did not (group 2). Most patients from group 1 had controlled glycemia. The secondary cultures showed tolerance induction to insulin or GAD65 in 14 and 10 patients, respectively. A high percentage of these patients (70–80%) belonged to group 1. Importantly, tDC induced antigen-specific T-cell hyporesponsiveness, since the responses against unrelated antigens were unaffected. These results suggest that tDC therapy against multiple antigens might be useful in a subset of T1D patients.  相似文献   
57.
目的:通过研究Wnt信号分子在大鼠中枢神经系统(CNS)的表达及分布,以探讨Wnt信号分子在CNS早期发育的可能调控机制,以及Wnt信号分子之间的功能联系.方法:应用免疫组织化学及双标记技术,观察了Wnt信号分子β-catenin、糖原合成酶激酶3β(Gsk-3β)、大肠腺瘤样息肉基因(APC)等关键调控分子在成年大鼠CNS的表达分布、细胞定位及共存关系.结果:免疫组织化学显色显示Gsk-3β阳性细胞多为具有突起的神经元样细胞,其主要分布区域包括新皮层、背内侧丘脑、海马、小脑浦肯野细胞及脑干多个核团.β-catenin与APC在分布模式上与Gsk-3β高度一致.双标记实验显示β-catenin与APC除神经元外,在部分星形胶质细胞也存在表达,而Gsk-3β则主要显示神经元定位.部分β-catenin阳性细胞,特别是室下层及海马区阳性细胞还呈现与神经前体细胞标记物巢蛋白的共存.结论:Wnt信号分子在CNS存在着密切相关的功能联系,同时在不同细胞及组织区域可能还具有其特有的生物效应,与神经前体细胞和神经胶质细胞增殖分化密切相关,对其相关信号机制有待深入研究.  相似文献   
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59.
Cytotoxic T lymphocytes (CTLs) play an essential role in immunological responses for tumor rejection. In the past decade, many tumor-associated antigens (TAAs) have been identified predominantly in melanomas. Several clinical trials based on such antigenic peptides with or without adjuvants brought about partially favorable results, suggesting that identification of more immunogenic TAAs is needed. We show here the successful establishment of human leukocyte antigen (HLA)-A24-restricted CTL (TcLHK2 line1) from a pleural effusion of lung cancer patient, using B7.1 (CD80) transduced autologous lung cancer cells as an antigen-presenting cell (APC). TcLHK2 line1 recognized autologous lung adenocarcinoma cell line LHK2 in an HLA-A24-restricted fashion. Moreover, this CTL line also recognized allogeneic HLA-A24-positive lung adenocarcinoma cell line, gastric carcinoma cell line and melanoma cell line. These data raise the possibility that co-stimulatory molecule B7.1 (CD80) plays important role to overcome the immunological tolerance. Furthermore, TcLHK2 line1 is a useful tool for the identification of widely expressed shared antigens restricted by HLA-A24. Further analysis of this CTL and autologous cancer cell line will bring about novel TAAs.  相似文献   
60.
Esophageal gastric inlet patches (EGIPs) comprise an island of heterotopic gastric columnar epithelium in the cervical esophagus with a reported prevalence of up to 10%. Usually the diagnosis is made by chance in the course of an upper gastrointestinal endoscopy. After histopathologic examination EGIPs can be classified as oxyntic (mucosal glands contain parietal cells), mucoid type (mucosa is composed solely of glands with mucous cells), or mixed type (presence of both: glands with parietal cells and glands of mucous cells). Despite their overall low incidence of clinically relevant conditions, EGIPs seem to be a significant entity. Few individuals with EGIPs report symptoms of globus sensations, dysphagia, hoarseness, or chronic cough that are often misinterpreted as an atypical manifestation of gastroesophageal reflux disease. It is known that these symptoms significantly compromise the patients' quality of life. Therefore, therapy should be initiated. However, proton pump inhibitors' response seems to be poor in these patients. We were able to show that an interventional ablative endoscopic therapy by argon plasma coagulation can be a safe and effective procedure. However, further researches are required to better understand the clinical significance of EGIPs and their association to symptoms.  相似文献   
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