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排序方式: 共有1954条查询结果,搜索用时 31 毫秒
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Ping L. Zhang Sayeed K. Malek Jeffery W. Prichard Fan Lin Taher M. Yahya Michael S. Schwartzman Ruth P. Latsha Evan R. Norfolk Thomas M. Blasick Mingyue Lun Robert E. Brown James E. Hartle Santosh Potdar 《American journal of transplantation》2005,5(3):604-607
Campath-1H has been used successfully for induction and has resulted in a low rate of acute cellular rejection (ACR) in renal transplantation in combination with various postoperative immunosuppression regimens. This study was undertaken to investigate the extent of monocyte involvement in ACR, with or without Campath-1H induction. We found that monocytes represented the majority of inflammatory cells in grades Ib or higher ACR, but not with Ia type of ACR, regardless of the status of Campath-1H induction. Cases of ACR, following Campath-1H induction, appear to demonstrate a 'pure form' of monocytic ACR, whereas monocytes were mixed with many other types of inflammatory cells in the cases of ACR in the absence of Campath-1H induction. In addition with Campath-1H induction, the cases of monocyte-predominant ACR were found to uniformly exhibit a good response to corticosteroid treatment. We conclude that monocyte-predominate ACR may represent a severe form of rejection, with or without Campath-1H treatment. 相似文献
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Abdul Rahman D El Kinge Rami A Mahfouz Ali I Shamseddine Ali T Taher 《Blood coagulation & fibrinolysis》2007,18(6):577-579
Recombinant activated factor VII has been Food and Drug Administration approved to treat hemorrhages in hemophiliac patients with inhibitors and in acquired hemophilia patients. Recombinant activated factor VII use has also been considered for the management of uncontrolled bleeding in a number of congenital and acquired hemostatic abnormalities. The myeloproliferative disorders are a group of clonal hematologic diseases where, frequently, abnormal platelet function is considered a hallmark. This is the first case report addressing the clinical benefit of off-label use of recombinant activated factor VII in an attempt to control intractable bleeding in a patient with a myeloproliferative disorder after splenectomy. 相似文献
7.
M Emre Celebi Hassan A Kingravi Bakhtiyar Uddin Hitoshi Iyatomi Y Alp Aslandogan William V Stoecker Randy H Moss 《Computerized medical imaging and graphics》2007,31(6):362-373
In this paper a methodological approach to the classification of pigmented skin lesions in dermoscopy images is presented. First, automatic border detection is performed to separate the lesion from the background skin. Shape features are then extracted from this border. For the extraction of color and texture related features, the image is divided into various clinically significant regions using the Euclidean distance transform. This feature data is fed into an optimization framework, which ranks the features using various feature selection algorithms and determines the optimal feature subset size according to the area under the ROC curve measure obtained from support vector machine classification. The issue of class imbalance is addressed using various sampling strategies, and the classifier generalization error is estimated using Monte Carlo cross validation. Experiments on a set of 564 images yielded a specificity of 92.34% and a sensitivity of 93.33%. 相似文献
8.
Uddin M Yang H Shi M Polley-Mandal M Guo Z 《Mechanisms of ageing and development》2003,124(7):811-817
Hypertension is an age-dependent disorder. Oxidative stress has been suggested to play a role in aging and age-dependent disorders. The objective of this study is to examine the oxidant and antioxidant status in the aorta of a mouse model with high blood pressure (BPH). Our results showed that the level of malondialdehyde (MDA) in the aorta of BPH mice was approximately 2.6-fold higher than that of the normal blood pressure (BPN) mice, suggesting an increased in vivo oxidative stress in the arterial wall of BPH mice. In addition, the release of hydrogen peroxide (H2O2) from the aorta of BPH mice was significantly faster than that of BPN mice. To determine if the increased H2O2 release is related to a down-regulation of antioxidant enzymes in the arterial wall, we measured the activities of the major antioxidant enzymes in mouse aortas. We observed that the activities of Cu/Zn-superoxide dismutase (SOD) and glutathione peroxidase-1 in BPH mice were similar to BPN mice. On the other hand, the catalase activity in the aorta of BPH mice was significantly reduced while the activities of Mn-SOD and extracellular (EC)-SOD in the aorta of BPH mice were significantly elevated as compared with BPN mice. These results suggest that increase in SOD activity and decrease in catalase activity might be responsible for the increased release of H2O2 in the arterial wall of BPH mice. 相似文献
9.
The role of a transmembrane protein, integrin alpha2beta1, to modulate the neural responses of cutaneous mechanoreceptors to mechanical indentation was examined using an isolated skin-nerve preparation in a rat model. Skin and its intact innervation were harvested from the medial thigh of the hindlimb and placed in a dish containing synthetic interstitial fluid. Using a standard teased nerve preparation, the neural responses of single slowly or rapidly adapting mechanoreceptors (SA or RA, respectively) were identified and the afferents categorized according to standard protocols (i.e. response to constant stimuli). The most sensitive spot of a mechanoreceptor's receptive field was identified and then stimulated using controlled compressive stress (constant or dynamic loads between threshold and saturation load for SAs and RAs, respectively). Loads were applied before, during, and after passive diffusion into the skin of a function-blocking anti-integrin alpha2 monoclonal antibody (FBmAb) or one of two types of control antibodies (immunoglobulin G or a FBmAb conjugated with a secondary antibody). The sensitivities of both SA and RA mechanoreceptors were profoundly reduced in the presence of the FBmAb, while not changing the waveforms of their action potentials or their adaptation properties. Both control antibodies had no significant effect on mechanoreceptors' sensitivities. Following removal of the FBmAb, the effects in some neurons were partially reversible. Taken together, the data from this study support the hypothesis that integrin alpha2beta1 plays a significant role in modulating mechanoreceptive response to compressive indentation. 相似文献
10.
Ghazzawi IM; Sarraf MG; Taher MR; Khalifa FA 《Human reproduction (Oxford, England)》1998,13(2):348-352
A prospective study was carried out to compare the fertilizing capability
and pregnancy outcome following intracytoplasmic sperm injection (ICSI)
using spermatozoa obtained from ejaculates, or surgically from epididymis
or seminiferous tubules. A total of 77 ICSI cycles (one per patient) was
included. In all, 28 patients had severe oligoasthenoteratozoospermia, 19
patients had obstructive azoospermia and 30 patients had non-obstructive
azoospermia. The main outcome measures were fertilization rate per injected
metaphase II oocyte and the clinical pregnancy rate per embryo transferred
back to the female recipients. In patients with severe
oligoasthenoteratozoospermia, the fertilization and pregnancy rates were 79
and 25 %. In patients with obstructive azoospermia, for whom epididymal
spermatozoa were used, these were 75 and 28%, and in the non-obstructive
group for which testicular spermatozoa were used for injection, they were
69 and 21% respectively. These rates were not significantly different in
the three groups (P = 0.85 and P = 0.14 respectively), suggesting that
spermatozoa from the ejaculates and epididymal or testicular biopsies are
able to fertilize equally by using ICSI. Live birth per embryo transfer was
significantly reduced in patients with non-obstructive azoospermia compared
to the other two groups. The high abortion rate (50%) in the group in which
testicular spermatozoa were used raises doubts about the developmental
competence of such embryos.
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