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1.
The risk of non-A, non-B hepatitis transmission by an intravenous immunoglobulin (IVIG) preparation was assessed in a prospective multicenter trial in 68 patients with primary immunodeficiency disorders (40 children or adolescents and 28 adults). During the 4-week prestudy evaluation period the clinical examinations and liver function tests including alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transpeptidase, alkaline phosphatase, and bilirubin were normal in all patients. The treatment consisted of three infusions of 200 mg IVIG (pH 4; pepsin procedure) per kilogram body weight at 2-week intervals. During the observation period of 24 weeks following the first infusion of the study IVIG, the patients were monitored at regular time intervals. No clinical and laboratory signs of hepatitis or liver dysfunction were noticed. All patients completed the study. In 5 patients, one isolated alanine aminotransferase value and in another patient one gamma-glutamyl transpeptidase value were moderately elevated, but always below 2.5 times the upper limit of the reference range. Similar isolated and transient elevations were observed for aspartate aminotransferase and alkaline phosphatase. It was concluded that the IVIG preparation did not transmit non-A, non-B hepatitis or other viral liver diseases.  相似文献   
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Lymphoepithelioma-like carcinoma of the bladder is an uncommon neoplasm, of which 49 cases have been described in the English literature, none of which has been studied for p53 protein expression. We studied three muscle-infiltrating cases of this tumor using immunohistochemical, in situ hybridization and polymerase chain reaction (PCR) methods. The three cases were positive for epithelial markers and negative for lymphoid antigens in the tumoral syncytial areas. The intensive infiltrate of small cells was negative for epithelial and positive for lymphoid markers. This population was mainly made up of cytotoxic T-lymphocytes, positive for TIA-1. p53 protein was intensely positive in more than 90% of the epithelial component nuclei, being negative in the lymphoid cells. PCR study did not show mutations on p53. Both lymphocytes and epithelium were negative for Epstein–Barr virus markers, such as the latent membrane protein and EBER (Epstein–Barr-encoded RNA). The prognosis was very good after radiotherapy and chemotherapy treatment, preserving the bladder despite the muscle infiltration. The presence of an intense cytotoxic T-lymphocyte population may be related to this good prognosis. Both aspects, p53 protein status and T-lymphoid population, had never been studied before in bladder lymphoepithelioma-like carcinoma.  相似文献   
3.
Langerhans cells (LC) take up Leishmania major and are critical for the induction of the parasite-specific T-cell response. Their functional activities are regulated by cytokines. We analyzed whether infection of LC with L. major modulates the expression of their cytokine receptors. The expression of the interleukin 4 (IL-4) receptor was increased on infected LC from susceptible mice but not on those from resistant mice. Moreover, IL-4 treatment strongly decreased the lipopolysaccharide-induced IL-12 response of infected LC from susceptible mice. This modulation of IL-4 receptor expression and IL-12 production by infection of LC with Leishmania may contribute to the development of Th2 cells and to susceptibility to infection.  相似文献   
4.
Precise control of cell proliferation and differentiation is critical for organogenesis. Geminin (Gem) has been proposed to link cell cycle exit and differentiation as a prodifferentiation factor and plays a role in neural cell fate acquisition. Here, we identified the SWI/SNF chromatin-remodeling protein Brg1 as an interacting partner of Gem. Brg1 has been implicated in cell cycle withdrawal and cellular differentiation. Surprisingly, we discovered that Gem antagonizes Brg1 activity during neurogenesis to maintain the undifferentiated cell state. Down-regulation of Gem expression normally precedes neuronal differentiation, and gain- and loss-of-function experiments in Xenopus embryos and mouse P19 cells demonstrated that Gem was essential to prevent premature neurogenesis. Misexpression of Gem also suppressed ectopic neurogenesis driven by Ngn and NeuroD. Gem's activity to block differentiation depended upon its ability to bind Brg1 and could be mediated by Gem's inhibition of proneural basic helix-loop-helix (bHLH)-Brg1 interactions required for bHLH target gene activation. Our data demonstrate a novel mechanism of Gem activity, through regulation of SWI/SNF chromatin-remodeling proteins, and indicate that Gem is an essential regulator of neurogenesis that can control the timing of neural progenitor differentiation and maintain the undifferentiated cell state.  相似文献   
5.
The feasibility and acceptability of cognitive behavior therapy for HIV-related peripheral neuropathic pain was examined and the potential efficacy of the intervention was compared with that of supportive psychotherapy in reducing pain, pain-related interference with functioning, and distress. Sixty-one patients were randomly assigned to receive six weekly sessions of cognitive behavior therapy or supportive psychotherapy. Thirty-three subjects completed the protocol. Both groups showed significant reductions in pain. The cognitive behavior group improved in most domains of pain-related functional interference and distress; the supportive psychotherapy group showed fewer gains. The high dropout rate suggests that psychotherapeutic treatments for HIV-related pain may have limited feasibility and acceptability.  相似文献   
6.
When research involves people, ethics are fundamental. In the health and social sciences, when qualitative methodologies are used, in addition to ensuring an ethical process approved by the ethics review board, it is also necessary to guarantee an ethical practice capable of responding adequately to the complex questions and dilemmas which arise as the study progresses. This theoretical article analyses some of the most sensitive issues involved in qualitative research and discusses the following questions: (a) How should ethics be approached when working with vulnerable groups? (b) Is informed consent enough? (c) Should we rethink anonymity? (d) What is the difference between confidentiality and anonymity? (e) What exactly do we mean by relational ethics? (f) How can we avoid hurting people, yet remain honest? In the conclusions, we discuss some basic aspects for ensuring ethical studies. This paper, therefore, may be of interest to all health and social researchers concerned about ensuring that their studies comply with ethical principles which recognise, protect and respect participants’ rights.  相似文献   
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Diarrhetic shellfish poisoning (DSP) toxins of algal origin are frequent contaminants of coastal waters and seafood. The potential risk for human health due to the continuous presence of these toxins in food has not been clearly established. We have used cerebellar primary cultures to investigate the effects of the DSP toxin dinophysistoxin-2 (DTX-2) on central nervous system neurons and glial cells. Exposure to DTX-2 produced neurotoxicity at concentrations starting at 2.5 nM, characterized first by disintegration of neurites and later by cell death. DTX-2-induced neurodegeneration required long exposures (at least 20 h), involved DNA fragmentation and condensation and fragmentation of chromatin, typical hallmarks of apoptosis, and required the synthesis of new proteins. The concentration that reduced by 50% the maximum neuronal survival after 24 h exposure to DTX-2 (EC50(24)) was approximately 8 nM. Morphology and viability of glial cells remained unaffected up to at least 15 nM DTX-2. Higher concentrations of the toxin caused strong shrinkage of glial cell bodies and retraction of processes, and a significant reduction of glial cell viability. Glial toxicity by DTX-2 involved typical apoptotic condensation and fragmentation of chromatin. Compared to neurons, the effect on glial cells was a much shorter process, and extensive glial degeneration and death occurred after 7 h exposure to DTX-2 (EC50(7) approximately 50 nM; EC50(24) approximately 30 nM). Although further experiments are needed to confirm these toxic actions in vivo, our in vitro data suggest that chronic exposure to amounts of DSP toxins below the current safety regulatory limits may represent a risk for human health that should be taken into consideration.  相似文献   
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