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91.
Assessment of left ventricular (LV) function in the catheterization laboratory is important to optimize treatment decisions and guide catheter-based local therapies. NOGA electromechanical mapping was developed to assess LV contraction during catheterization; however, quantitative analysis of its "local shortening" (LS) algorithm and direct comparison with conventional methods are lacking. We evaluated the accuracy of NOGA-based regional and global function by examining its ability to detect pharmacologically induced changes in contractility compared with echocardiography. Ten anesthetized pigs were paced to ensure a constant heart rate throughout the experiment. Electromechanical maps of the LV and short-axis echocardiograms were obtained 1) at baseline, 2) during intravenous dobutamine, and 3) after intravenous propranolol. NOGA LS and ejection fraction (EF) consistently increased under dobutamine and decreased after propranolol. NOGA LS and NOGA and echocardiography circumferential shortening correlated highly with one another (r > 0.80), as did NOGA EF with echocardiography EF (r = 0.92), although absolute values differed somewhat. Thus NOGA-based global and regional function correlates closely with echocardiography and is sensitive to changes in contractility, but, at the upper end of the scale, LV function is underestimated.  相似文献   
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Several bone marrow cells and lymphocyte subpopulations, known as veto cells, were shown to induce transplantation tolerance across major histocompatibility Ags. Due to the low frequency of the effector T cells against which the veto cells inhibitory activity is aimed, the fate of the effector cells was traditionally followed indirectly by functional limiting dilution assays, which are cumbersome and depend on numerous parameters. In the present study the fate of the effector T cells was monitored directly by FACS, using TCR transgenic mouse CD8(+) T cells in which the transgene is directed against H-2(d) (the 2C model). This assay is validated by demonstrating the potency, selectivity, radiation sensitivity, and contact dependency of anti-third-party CTLs previously demonstrated by the limiting dilution assay. In contrast to veto CTLs, nonactivated CD8(+) T cells lack veto activity. Comparison by FACS in the 2C model revealed a hierarchy of veto cells, in the order of veto CTLs activated NK cells, activated CD4(+) T cells, and activated B cells. The latter cells as well as nonactivated CD4(+) or NK cells were shown to be completely devoid of veto activity.  相似文献   
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Thus, we can conclude that marrow transplantation has already influenced medical practice greatly. It has offered a treatment which often cures patients of more than 20 otherwise lethal diseases. The treatment so horrendously difficult and dangerous at first has already been greatly improved, simplified, and made much safer. The availability of a suitable donor has been much extended and real progress has been made in prevention and perhaps even in treatment of graft-versus-host disease. This has made possible the option of marrow transplantation for every patient in whom we think the treatment may be beneficial. The problem underlying many cases of interstitial pneumonia has been identified and patients are already benefitting clinically from this progress. Progress has also been made which promises antiviral therapy which could reduce, prevent, and ultimately eliminate the intercurrent virus infections which limit the applicability of marrow transplantation, especially for children with severe immunodeficiencies. I do not know how far this line of investigation can be taken. However, just as we have learned stepwise to use marrow transplants from matched siblings to treat many diseases, to use fetal liver in place of bone marrow, to employ matched relative donors when a matched sibling is not available, and, finally, even to use parental donors to achieve correction of SCID, we now have good reason to believe that, ultimately, we can use marrow transplantation without fear of GVHD to address many additional genetically determined and acquired diseases; certainly, for those diseases that involve any of the cells that are derived from bone marrow cells, and perhaps for those attributable even to cells of other organs and tissues, the functions of which are, in whole or in part, a consequence of interactions of marrow-derived cells and cells of ectodermal or endodermal origin, marrow transplantation may be useful. To us, the future of marrow transplantation as a major modality of treatment or prevention of many diseases, including hemoglobinopathesis, immunodeficiencies, hematologic abnormalities, abnormalities of function of marrow-derived cells, and even inborn errors of function of cells of organs and tissues not of marrow origin, seems bright, indeed. Further, with the capacity to introduce resistance genes against viruses and malignancies, autoimmune diseases, and diseases dependent on anomalies of immune response genes, marrow transplantation for many other diseases seems a more remote possibility.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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A complete system has been developed to utilize histologicalserial sections for two- and three-dimensional image reconstructions.Eighty to 120 sections are digitized using a personal computingsystem augmented with a imaging board and CCD camera. The imagefiles are transmitted to a VAX computer for processing and imagereconstruction, and the processed images are transmitted backto the personal computer for display and recording using a filmrecorder or PostScript printer. The software developed for thesystem allows serial sections to be placed into proper registrationin a 2563 array, 256 grey levels. Autoradiographs of the sectionsare obtained in the presence of appropriate standards whichare used to recalibrate grey levels to represent linearly theradioactivity of each pixel in the sections and scale the valuesto allow maximum use of the grey scale. Starting from coronallysectioned material the system has been used to analyse and reconstructrat nasal turbinates. In two dimensions horizontal and sagittalsections have been obtained while in three dimensions back-to-frontand surface-rendered images have been constructed. Useful renderingof differential metabolic activity within an organ of complexgeometry has been obtained, and there appears to be no reasonwhy the system cannot be used for any material for which serialsectioning is appropriate. Received on November 29, 1989; accepted on February 28, 1990  相似文献   
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Software has been developed to allow the use of a number ofparameters in the comparative representation of proteins incolor and monochrome dot matrices. They include the parametersof partial specific volume, residue bulkiness, the mean areaburied of side chains, seven additional hydropathy scales, mutability,polarity, secondary structure propensities, energy/residue,energy/atom, Rf values, the pKs at the N and C terminals, user-definedparameters and, if desired, randomly generated values. Manyof these parameters can be combined in n space using an algorithmbased on the Euclidian distance relationship in order to deriveconsensus values. The problem of scoring matched identitiesis addressed and the user may stipulate that they score 100on a 0–100 scale or be determined from the Dayhoff MDM78values with the rest of the matrix scaled appropriately. ThePAMs matrix has been incorporated in such a way to allow theuser to stipulate various PAM's values or estimated percentagedifference between two peptide sequences, and converting tolog odds values. In addition, the similarity ring developedby Swanson and the matrix proposed by Bacon and Anderson havebeen adapted for use in the program. Color indices have beenutilized to give a ‘third dimension’ to the projections,allowing the user to judge the degree of similarity of differentregions which are represented. The software also provides forthe plotting of nucleotides in which case color is used to codeindividual nucleotides, purines versus pyrimidines, or similarcolors are used to differentiate between A and T bases on theone hand, and G and C on the other. Received on December 31, 1987; accepted on May 18, 1988  相似文献   
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