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101.

Background

Some young women experience delays in diagnosis of cervical cancer, but little research about ways of studying these delays has been published. A major challenge is that gynaecological symptoms are common in young women, but cervical cancer is rare. This study describes the development and testing of a measure for studying delays in diagnosis in young women with cervical cancer.

Methods

Prospective development of an interview measure and testing of its ability to reliably and systematically collect relevant data in two large hospitals in London, UK using 27 women aged 18–40 diagnosed with cervical cancer in the previous two years. We developed a semi-structured interview schedule and data extraction form to systematically collect data on symptoms (including nature and duration) and risk factors for delayed diagnosis from young women with cervical cancer. We piloted the measure among young women with cervical cancer (audiorecording it with their permission), refining it iteratively. To complete the measure, we developed a database for managing the data and a manual for using the schedule. Two researchers extracted data from the recorded interviews to assess inter-rater reliability.

Results

The final interview schedule yielded quantitative data on the nature and duration of symptoms and risk factors for delayed diagnosis. Inter-rater reliability was high. In the pilot, 12 of the 27 women were diagnosed via symptomatic presentation. Median time from the symptom triggering presentation to presentation was one month (interquartile range 0–4 months). Median time from presentation to diagnosis was three months (interquartile range 1–8.5 months).

Conclusions

We have developed a reliable tool for measuring the nature and duration of symptoms in young women with cervical cancer. Pilot data suggest that a substantial proportion of women experience delay between first presentation and diagnosis.
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102.
Humans lacking the CD3gamma subunit of the pre-TCR and TCR complexes exhibit a mild alphabeta T lymphopenia, but have normal T cells. By contrast, CD3gamma-deficient mice are almost devoid of mature alphabeta T cells due to an early block of intrathymic development at the CD4(-)CD8(-) double-negative (DN) stage. This suggests that in humans but not in mice, the highly related CD3delta chain replaces CD3gamma during alphabeta T-cell development. To determine whether human CD3delta (hCD3delta) functions in a similar manner in the mouse in the absence of CD3gamma, we introduced an hCD3delta transgene in mice that were deficient for both CD3delta and CD3gamma, in which thymocyte development is completely arrested at the DN stage. Expression of hCD3delta efficiently supported pre-TCR-mediated progression from the DN to the CD4(+)CD8(+) double-positive (DP) stage. However, alphabetaTCR-mediated positive and negative thymocyte selection was less efficient than in wild-type mice, which correlated with a marked attenuation of TCR-mediated signaling. Of note, murine CD3gamma-deficient TCR complexes that had incorporated hCD3delta displayed abnormalities in structural stability resembling those of T cells from CD3gamma-deficient humans. Taken together, these data demonstrate that CD3delta and CD3gamma play a different role in humans and mice in pre-TCR and TCR function during alphabeta T-cell development.  相似文献   
103.
104.
High-dose chemotherapy with or without radiotherapy followed by autologous transplantation of hematopoietic progenitor cells is an effective treatment for patients with high-risk or relapsed non- Hodgkin's lymphoma. Chemotherapy and/or hematopoietic growth factors have been used to mobilize progenitor cells in the peripheral blood for transplantation. However, the mobilized blood cell products have been found to be frequently contaminated with tumor cells, and techniques have not been developed to purge tumor cells from these products. In addition, the minimum number of hematopoietic progenitor cells required for engraftment has not yet been fully elucidated. We treated 21 patients with a single infusion of cyclophosphamide (4 g/m2) followed by daily administration of granulocyte colony-stimulating factor (G- CSF). After recovery of the white blood cell count, a single 3-hour apheresis collection was performed. The apheresis product was then applied to a discontinuous Percoll gradient. The low-density fractions resulting from this separation procedure were enriched for CD34+ progenitor cells (total cell yield, 19.5%; CD34+ cell recovery, 81.2%). These enriched cellular products were treated with a panel of anti-B cell or anti-T cell monoclonal antibodies and complement in an effort to remove residual tumor cells. After treatment of the patient with myeloablative therapies, the enriched and purged cells were reinfused. Hematologic recovery was rapid, with median neutrophil engraftment in 10 days [absolute neutrophil count (ANC), greater than 0.5 x 10(9)/L] and 11 days (ANC, greater than 1.0 x 10(9)/L). Median platelet transfusion independence required 13 days. The rapidity of multilineage engraftment correlated with the number of CD34+ cells per kilogram that were infused. Patients who received more than 2 x 10(6) CD34+ cells per kilogram had rapid hematologic engraftment, whereas those patients transplanted with less than 2 x 10(6) CD34+ cells per kilogram had slower platelet recovery. Modeling studies using a lymphoma cell line with a t(14; 18) chromosomal translocation demonstrated the successful removal of tumor cells assayed using the polymerase chain reaction (PCR) after the processing and purging. Four of the 21 patients had PCR- detectable lymphoma cells in the bone marrow and peripheral blood; however, the enriched and purged blood products reinfused in all four did not contain detectable tumor cells.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
105.
Steady state levels of factor X mRNA in liver and Hep G2 cells   总被引:1,自引:0,他引:1  
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106.
Hancock  WW; Zola  H; Atkins  RC 《Blood》1983,62(6):1271-1279
Eight monoclonal antibodies to cell surface antigens of human monocytes were evaluated as immunologic markers for recognition of macrophages in sections of normal and diseased tissues, using immunoperoxidase and enzyme histochemical techniques. Monoclonal antibodies assessed were PHM2, PHM3, FMC17, FMC32, FMC33, FMC34, OKM1, and 63D3. Sites studied were human bone marrow, blood, lymph node, spleen, thymus, liver, kidney, lung, and peritoneal lavages, rejecting renal allografts containing inflammatory macrophages, and granulomata showing epithelioid and multinucleate giant cell formation. All antibodies bound to at least some tissue macrophages and, except for FMC32 and FMC33 antibodies, which were identically distributed, each antibody had a distinctive tissue distribution. Some antigens were shared by other bone-marrow-derived cells (megakaryocytes and cortical thymocytes), endothelium, epithelium, and dendritic cells. Antigenic differences were also detected between mononuclear phagocytes present at different sites, different stages of differentiation, and likely different states of activation. These studies provide evidence of major antigenic differences between various populations of human mononuclear phagocytes. They therefore indicate the need for careful evaluation of experiments involving the recognition of macrophages in tissue sections and smears based solely on the use of antimonocyte monoclonal antibodies.  相似文献   
107.
Nucleotide oligomerization and binding domain (NOD)-like receptors (NLRs) are a major constituent of the cytosolic innate immune-sensing machinery and participate in a wide array of pathways including nuclear factor κB (NF-κB), mitogen-activated protein kinase (MAPK), inflammasome, and type I interferon (IFN) signaling. NLRs have known roles in autoimmune, autoinflammatory, and infectious diseases. With respect to virus infection, NLRP3 is the most extensively studied NLR, including mechanisms of activation and inhibition. Furthermore, the importance of NLRP3 in both innate and adaptive immunity has been demonstrated. In comparison to NLRP3, the roles of other NLRs during virus infection are only just emerging. NLRC2 is an important activator of innate antiviral signaling and was recently found to mitigate inflammation during virus infection through autophagy. Finally, functions for NLRX1 in immune modulation and reactive oxygen species production require further examination and the importance of NLRC5 as a transactivator of major histocompatibility complex (MHC) class I and antigen presentation is currently developing. In this review, we discuss current knowledge pertaining to viruses and NLRs as well as areas of potential research, which will help advance the study of NLR biology during virus infection.  相似文献   
108.
灰毡毛忍冬化学成分研究V灰毡毛忍冬素F和G的结构测定   总被引:5,自引:0,他引:5  
Lonicera macranthoides Hand. -Mazz of Caprifoliaceae is the sources of Jinyinhua, which is a well known antipyretic and antidote in traditional Chinese medicine. Chemical studies led us to isolate 11 new compounds.Further purification of a bioactive fraction from the EtOAc soluble portion yielded two new compounds named macranthoin F and G,Their structures wereelucidated as methyl 3,4-O-dicaffeoylquinate(Ⅰ)and methyl 3,5-O-dicaffeoylquinate(Ⅱ).  相似文献   
109.
During antigen recognition, T cells show high sensitivity and specificity, and a wide dynamic range. Paradoxically, these characteristics are based on low-affinity receptor-ligand interactions [between the T-cell antigen receptor (TCR-CD3) complex and the antigen peptide bound to MHC]. Recent evidence indicates that the TCR-CD3 is expressed as multivalent complexes in the membrane of non-stimulated T cells and that conformational changes in the TCR-CD3 can be induced by strong but not weak agonists. Here, we propose a thermodynamic model whereby the specificity of the TCR-CD3-pMHC interaction is explained by its multivalent nature. We also propose that the free energy barriers involved in the change in conformation of the receptor impose a response threshold and determine the kinetic properties of recognition. Finally, we suggest that multivalent TCR-CD3s can amplify signals by spreading them from pMHC-engaged TCR-CD3s to unengaged complexes as a consequence of the cooperativity in the system.  相似文献   
110.
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