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31.
32.
Gary L. Hansen PhD ; Ephraim M. Sparrow PhD ; Narasimharao Kommamuri BE ; Paul A. Iaizzo PhD 《Wound repair and regeneration》1996,4(3):386-392
This study examined the use of cutaneous reactive hyperemia as a means for noninvasive assessment of wound severity of newly formed temperature-modulated pressure injuries in a porcine model. Two methods to quantify the extent of the reactive hyperemic reflex were developed. First, color image analysis was used to measure the hue of injured tissue. The specific hue of the skin surface of the wounded site was found to provide an indication of the severity of the wounds. Second, infrared imaging, coupled with computer image processing, was used to detect differences in skin temperature. The relative surface temperature of the wounds showed a strong correlation with the presence or absence of deep tissue injury. Both techniques correlated with the severity of the injuries as determined by a histologic assessment of biopsied tissue, but infrared imaging provided the better means to assess wound depth. 相似文献
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34.
Inhibition of calcineurin phosphatase activity in adult bone marrow transplant patients treated with cyclosporine A 总被引:2,自引:1,他引:1
Pai SY; Fruman DA; Leong T; Neuberg D; Rosano TG; McGarigle C; Antin JH; Bierer BE 《Blood》1994,84(11):3974-3979
In vitro studies have demonstrated that cyclosporine A (CsA) acts by inhibiting the phosphatase activity of calcineurin, an important mediator of T-cell activation. The relationship of CsA administration in vivo, calcineurin activity, and graft-versus-host disease (GVHD) has yet to be studied. The calcineurin activities of mononuclear cells isolated from 62 bone marrow transplant recipients and 12 normal volunteers were determined and analyzed with respect to administration of CsA, presence or absence of CsA in plasma, and presence or absence of GVHD. Of 62 patients, 33 were taking CsA and 29 were not. Early posttransplant (< 100 days), the calcineurin activity of patients on CsA was significantly lower than that of patients not on CsA (P = .0004) and than that of normal volunteers (P < .0001). Similarly, late posttransplant (> 100 days), the calcineurin activity of patients taking CsA was inhibited compared with normal volunteers (P < .05). The calcineurin activity of patients with acute GVHD who were taking CsA was lower than that of patients on CsA without acute GVHD matched for time posttransplant (P = .02). Calcineurin activity in patients on CsA with chronic GVHD was similar to those without chronic GVHD on drug. In conclusion, calcineurin activity is significantly suppressed by in vivo administration of CsA. The lower calcineurin activity of patients on CsA with acute GVHD suggests that CsA-resistant GVHD is not the result of inadequate suppression of calcineurin activity. These data suggest that if inhibition of calcineurin is the only physiologic target of CsA administration, simply increasing doses of CsA or treatment with other inhibitors of calcineurin, such as FK506, would not be expected to ameliorate GVHD. 相似文献
35.
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The identification of small numbers of leukemic cells in the cerebrospinal fluid (CSF) presents a diagnostic problem in the treatment of children with acute lymphoblastic leukemia (ALL). We adapted a latex sphere rosetting technique to allow us to identify simultaneously cell surface markers and cell morphology in 199 CSF samples from 34 patients and 14 control subjects. In patients without leukemic meningitis, the majority of CSF lymphocytes (69%) were found to be mature T cells positive for OKT11. A much smaller number of cells (8%) were found to be B cells positive for la. In these children, only 3% of CSF lymphoid cells expressed the common acute lymphoblastic leukemia antigen (CALLA). Similar results were found in the control subjects. By contrast, 28 CSF samples from nine children with varying numbers of CSF lymphoblasts had much greater proportions of CALLA- and la-positive CSF cells (24% to 96%). Leukemic meningitis was present in one of these patients and later developed in four others. However, three patients with small numbers of lymphoblasts present but with low proportions of CALLA-positive CSF cells (less than 5%) subsequently had normal CSF examinations. We found the use of this rosetting technique valuable in providing information complementary to that obtained from cell morphology alone about the possible malignant nature of small numbers of lymphoblast-like CSF cells seen on cytocentrifuge preparations in children with ALL. 相似文献
38.
Optical imaging and electrophysiology of rat barrel cortex. I. Responses to small single-vibrissa deflections 总被引:2,自引:2,他引:0
A study was undertaken to investigate the response of the rodent
somatosensory barrel cortex to single-whisker, near-threshold vibrissal
stimuli. Cortical responses to controlled whisker deflections were recorded
by (i) conventional multi-unit extracellular recording within the
cytochrome oxidase rich barrels centers and the interbarrel septa, and (ii)
intrinsic signal optical imaging, a technique that provides a spatial view
of cortical activation thought to be related to the deoxygenation of
hemoglobin in activated areas. Barrel cortex neurons responded weakly to
whisker deflections of 0.04 degrees. Their response to a series of small
stimuli of increasing amplitude was well-fitted by a logarithmic function.
Responses to larger stimuli declined monotonically with distance from the
center of the barrel column, and were characterized by greater onset and
offset firing rates, by greater post-excitatory reduction of firing to
below spontaneous levels, and by shorter response latency. In comparison to
measurements taken previously from primary vibrissal afferent fibers, we
conclude that cortical cells can respond to activity in a very small
fraction of first-order sensory neurons.
相似文献
39.
Maturo VG; Zusmer NR; Gilson AJ; Smoak WM; Janowitz WR; Bear BE; Goddard J; Dick DE 《Radiology》1980,137(2):457-463
Innovations in design of a dedicated breast scanner resulted in automation of the scanning process, the production of high resolution images of the whole breast and an efficient mode of image review. The results of clinical evaluation of the prototype of this breast scanner investigating normal breasts as well as benign and malignant breast lesions are presented. 相似文献
40.
Rajasekaran S Thapar V Dave H Huang CH 《Journal of clinical monitoring and computing》2005,19(4-5):351-359
Multiple sequence alignment (MSA) is a vital problem in biology. Optimal alignment of multiple sequences becomes impractical
even for a modest number of sequences [1] since the general version of the problem is NP-hard. Because of the high time complexity
of traditional MSA algorithms, even today's fast computers are not able to solve the problem for large number of sequences.
In this paper we present a randomized algorithm to calculate distance matrices, which is a major step in many multiple sequence
alignment algorithms. The basic idea employed is sampling (along the lines of [2]). We also illustrate how to parallelize
this algorithm.
In Section 1 we introduce the problem of multiple sequence alignments. In Section 2 we provide a discussion on various methods
that have been employed in the literature for Multiple Sequence Alignment. In this section we also introduce our new sampling
approach. We extend our randomized algorithm to the case of non-uniform length sequences as well. We show that our algorithms
are amenable to parallelism in Section 3. In Section 4 we back up our claim of speedup and accuracy with empirical data and
examples. In Section 5 we provide some concluding remarks. 相似文献