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101.
Primary cutaneous CD30+ lymphoproliferative disorders are the second most common type of primary cutaneous lymphomas. Involvement of the ocular adnexa is rare. Very few have been reported affecting the eyelid primarily. The authors present 2 patients with primary cutaneous anaplastic large-cell lymphoma involving the eyelid alone. Systemic workup excluded disease elsewhere. Both patients showed complete regression of their lesion following biopsy only and no other treatment, albeit with limited follow up. A surgically induced inflammatory or immune-mediated response could have played a role in the regression of these lesions.  相似文献   
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Patients with large intracoronary thrombi represent a difficult management problem for the interventional cardiologist. We report 10 cases of challenging thrombi treated percutaneously using varying combinations of deep guide catheter engagement, guide aspiration, dedicated catheter aspiration and withdrawal of a distal filter vascular protection device. These cases demonstrate interventional options which may be considered for such patients.  相似文献   
105.
Hasan  AA; Cines  DB; Ngaiza  JR; Jaffe  EA; Schmaier  AH 《Blood》1995,85(11):3134-3143
An important biologic function of high-molecular-weight kininogen (HK) is to deliver bradykinin (BK) to its cellular receptors. Internalization and degradation of HK may provide a mechanism by which endothelial cells modulate the production of BK and control its activities. Therefore, we investigated the binding and subsequent distribution of biotinylated-HK (biotin-HK) associated with human umbilical vein endothelial cells (HUVEC). HUVEC bound 3 to 4 times more HK and with greater avidity at 1 to 3 hours at 37 degrees C than at 4 degrees C (Bmax = 1.0 +/- 0.02 x 10(7) molecules/cell, kd = 7 +/- 3 nmol/L v Bmax = 2.6 +/- 0.2 x 10(6) molecules/cell, kd = 46 +/- 8 nmol/L). However, there was no evidence that the difference was caused by internalization of HK at the higher temperature. First, the same amount of biotin-HK was associated with nonpermeabilized and permeabilized HUVEC using buffers containing 20 to 50 mumol/L zinc ion in the absence or presence of 2 mmol/L calcium ion. Second, binding of biotin-HK to HUVEC was approximately 92% reversible at 1 hour when the cells were maintained at both 37 degrees C and 4 degrees C. Third, neither chloroquine nor primaquine altered the amount of biotin-HK bound to HUVEC. Fourth, biotin-HK bound to HUVEC was almost completely removed by pronase. Fifth, the nonpermeable dye, crystal violet, almost completely quenched the fluorescence signal emitted by HUVEC-associated fluorescein isothiocyanate (FITC) HK. Finally, the localization of HUVEC-bound FITC-HK was restricted to the membrane as shown by laser scanning confocal microscopy. The expression of HK binding sites had an absolute requirement for metabolic energy, but was not dependent on new protein synthesis. Membrane-bound HK contributed to the anticoagulant nature of endothelial cells by blocking human alpha-thrombin binding and its resultant induction of prostacyclin formation. These studies indicate that HK is not internalized by HUVEC, but remains primarily on cell surfaces to be accessible for BK liberation and to modulate the binding and actions of alpha-thrombin.  相似文献   
106.
Light chain deposition disease (LCDD) results from a propensity of some human monoclonal L chains to form tissue deposits. We designed an experimental model for in vivo expression of human kappa L chain sequences in mice and compared a somatically mutated LCDD chain with a closely related control kappa chain, both encoded by the unique V kappa IV gene. Mice secreting the LCDD chain but not those producing the control chain showed deposits with a distribution similar to that observed in patients. These data show that discrete changes in V region sequences can play a major role in tissue deposition of human L chains.  相似文献   
107.
Ralph  QM; Brisco  MJ; Joshua  DE; Brown  R; Gibson  J; Morley  AA 《Blood》1993,82(1):202-206
The Ig heavy chain (IgH) gene was used as a marker to investigate clonal succession and the origin of the neoplastic cell in multiple myeloma. The polymerase chain reaction (PCR) was used to amplify a section of the rearranged IgH gene at diagnosis and at progression in 21 patients who had exhibited a plateau phase. A monoclonal PCR product was seen for 16 of the patients and the product present at progression was of the same molecular weight as that at diagnosis. This finding suggests that the IgH rearrangement present at diagnosis and progression was the same. This was confirmed by sequencing the IgH gene in 10 patients. The IgH genes were found to be hypermutated at diagnosis, but no further hypermutation occurred during the course of the disease. The results provide evidence that the neoplastic cell in myeloma may originate as a memory B cell, plasmablast, or plasma cell, and suggest that progression beyond the plateau phase is not caused by clonal succession.  相似文献   
108.
Twenty-four patients whose cells contained a variety of 11q23 rearrangements, including translocations, insertions, and an inversion, were studied using fluorescence in situ hybridization with cosmid, phage, and plasmid probes mapped to 11q22-24. In 17 patients, the breakpoints of the common 11q23 translocations involving chromosomes 4, 6, 9, and 19 as well as some uncommon translocations involving 3q23, 17q25, 10p11, and an insertion 10;11 were all located in the breakpoint cluster region of the MLL gene, regardless of age, phenotype of disease, or involvement of a third chromosome. The breakpoints in 11q23 in the other 7 patients with a t(7;11)(p15;q23), inv(11)(p11q23), t(4;11)(q23;q23), der(5)t(5;11)(q13;q23), ins(10;11)(p11;q23q24), t(11;14)(q23;q11), or t(11;18;11) (p15;q21;q23) were located either centromeric to CD3D or telomeric to THY1. Thus, although most 11q23 rearrangements, involve the same breakpoint cluster region of MLL, there is heterogeneity in the breakpoint in some of the rare rearrangements.  相似文献   
109.
Summary Type 1 (insulin-dependent) diabetes mellitus is associated with abnormalities of circulating lymphocyte subsets and autoantibodies. To investigate the prevalence of these in non-diabetic siblings and non-diabetic parents of children with Type 1 diabetes, we analysed T-cell subsets of function and activation in 31 families with an index case of Type 1 diabetes and related these to autoantibodies and HLA DR type. Using two and three colour cytofluorimetry, we studied total and activated (HLA-DR+) CD3+, CD4+, CD8+ lymphocytes and on CD4+ lymphocytes the CD45RA/RO “naive” and “memory” cell phenotypes. Diabetic children (mean duration of disease 3.1 years) had a reduced total lymphocyte count (p <0.05), their non-diabetic siblings a reduced CD4+ T-helper cell count (p <0.05), and their parents a reduced percentage and number of CD3+ T cells (p <0.01 and p <0.05) compared with age-matched control subjects. Diabetic children, their siblings and parents all had significantly increased levels of activated CD4+ T-helper cells (p <0.01, p <0.05 and p <0.01). In diabetic children and their siblings there was a significant over-expression of the CD45RO “memory” cell marker and significant under-expression of the CD45RA “naive” cell marker, whilst these were normal in the parents. Islet cell antibody positive diabetic children had significantly higher levels of CD45RO-expressing CD4+ lymphocytes than those who were islet cell antibody negative (p <0.05). Amongst the siblings and parents, possession of HLA-DR4 was associated with lower percentages of CD4+ and higher percentages of CD8+ T cells. These findings extend current knowledge about the role of immunoregulatory CD45RA/ RO cells in Type 1 diabetes. In addition, they demonstrate lymphocyte subset abnormalities in unaffected family members, some of which may be influenced by HLA DR alleles. [Diabetologia (1994) 37: 155–165] Received: 1 March 1993 and in final revised form: 16 August 1993  相似文献   
110.
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