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91.
Cell tracking in vivo continues to provide significant insights into hematopoietic cell function and donor cell engraftment after transplantation. The combination of proliferation tracking dyes and induced expression of reporters with advanced imaging modalities has led to better understanding of qualitative and quantitative aspects of hematopoietic cells' homing, seeding and engraftment. Currently, there is no single technique that allows in vivo tracking of cells with molecular resolution, thus several techniques need to be combined. Recent developments promise better implementation of non-invasive imaging modalities to study functional and molecular characteristics of stem cells. 相似文献
92.
Abstract – The use of rigid fixation in children is controversial and may cause growth retardation along cranial suture lines. Intermaxillary fixation for mandibular fractures should be used cautiously as bony ankylosis in the temporomandibular joint (TMJ) and trismus may develop. The high osteogenic potential of the pediatric mandible allows non-surgical management to be successful in younger patients with conservative approaches. In this case, successful conservative treatment of mandibular fracture of a 3-year-old patient is presented. 相似文献
93.
Previous experimental epidemiologic and clinical studies have shown a significant reduction in colorectal cancer occurrence and mortality among individuals taking NSAIDs. NSAIDs inhibit the enzymatic activity of both isoforms of cyclo-oxy genase (COX-1 and COX-2), which regulate prostaglandin synthesis. COX-2 is an inducible enzyme that is overexpressed at sites of inflammation and in several epithelial cancers. Several studies have indicated that COX-2 overexpression appears to be involved in tumorigenesis by promoting cell division and proliferation, inhibiting apoptosls, stimulating anglogenesls, altering cell adhesion, and enhancing tumor cell invasiveness. Blocking of these activities by COX-2 selective inhibitors is considered the main mechanism that explains the anticarcinogenic effect of COX-2 selective Inhibitors. In addition, other independent COX-2 mechanisms have been described. Treatment with selective COX-2 inhibitors has shown promising results In the suppression of colon polyps, both in animal models for familial adenomatous polyposis (FAP) and in patients with FAP, and recent clinical studies have Identified the potential benefit of these agents for colon cancer chemopreventlon. However, serious concerns have been raised regarding the potential adverse effects of long-term selective COX-2 inhibitor use, most notably those within the cardiovascular system, such as myocardial Infarctions, strokes, and increased blood pressure. The role of COX-2 inhibitors in cancer chemopreventlon is still evolving and a careful risk/benefit analysis of the recent clinical studies would mandate the precise clinical setting that these drags can be used in. 相似文献
94.
Nadir Arber Eliezer Liberman Yafa Vered Gershon Fink Edith Marom Yechezkel Sinai Amir Shiber Jack Pinkhas Moshe Aronson Shlomo Berliner 《Stress and health》1993,9(2):75-82
This article further explores the effects of stress on leukocyte adhesiveness. The concentration of plasma catecholamines as well as the LAA values were examined in 16 volunteers during a cold pressor test and in 15 volunteers following physical activity. A significant correlation between LAA values and plasma norepinephrine, dopamine and epinephrine was noted. In addition, experimental studies of anaesthetized dogs infused with dopamine and norepinephrine showed increased LAA values, and an insulin-induced hypoglycaemic animal model for adrenergic stress indicated an inverse correlation between serum glucose concentrations and LAA values. Finally, in the presence of an MAO inhibitor, norepinephrine significantly increased the state of LAA in vitro. Thus, there exists an association between adrenergic stress and the appearance of sticky leukocytes in the circulating pool. We assume that, at least in part, this stickiness results from a direct effect of the catecholamines on the adhesive properties of the cells. Other factors might be related to the decreased endothelial adhesiveness towards the white blood cells as well as the concomitant effect of other mediators released during stress. This study also supports our notion that the state of LAA in the peripheral blood can serve as a useful stress marker. 相似文献
95.
The purpose of this study was to compare the load to failure of different common suturing techniques with repair devices. Seventy-one calf medial menisci were cut to simulate peripheral longitudinal tears and repaired with one of 13 repair techniques. The two parts of the meniscus were pulled using the Instron tensometer until failure occurred. The techniques and repair devices tested were vertical (0 PDS, 2-0 PDS, 2-0 Ethibond), horizontal (0 PDS, 2-0 PDS, 2-0 Ethibond) suturing, T-fix, Mitek, Clearfix screw, Clearfix dart, Biostinger, S-D-sorb, and Artrex dart. The strongest repair method in our study was the vertical sutures with 0 PDS. In this study the mean failure strength of all meniscal repair devices was lower than that of the vertical and horizontal suturing techniques. All meniscus repair devices except T-fix and in some the Arthrex dart (40% broken up) pulled out of the menisci. Devices which had only horizontally placed barbs had lower mean failure strength. Failure strength of T-fix was similar to horizontal sutures with 2-0 Ethibond and 2-0 PDS. In conclusion, because all meniscal repair devices had inferior results, when such devices are used, postoperative rehabilitation should not be hastened, and their inferior primary stability should be kept in mind. 相似文献
96.
Ahmet Turan Yilmaz Ertugrul Ozal Nadir Barindik Celalettin Günay Harun Tatar 《European journal of cardio-thoracic surgery》2002,21(5):794-799
OBJECTIVE: Harvesting of multiple arterial grafts is commonly associated with prolonged operating times and increased trauma in complete arterial coronary artery bypass grafting (CABG). Using sequential grafting techniques, CABG is possible with only two arterial grafts in multi-vessel coronary artery disease (CAD). However, sequential grafting may not be convenient for all circumstances and sometimes surgical technique may be challenging. We present our experience in the use of radial artery (RA) Y-graft on a routine basis. METHODS: Between January 1996 and November 2001, 127 patients (aged 63+/-8 years) with the diagnosis of multi-vessel disease underwent complete arterial revascularization using left internal mammarian artery (LIMA) and RA. Left ventricular ejection fraction ranged from 23 to 65% (mean 51+/-11%). Triple-vessel disease was present in 73.2% of patients. We used the division technique of RA during harvesting and formation of one or more composite Y-grafts of the RA itself to allow end-side rather than sequential anastomoses without any significant decrease the usable conduit length. The results of this technique were compared with the data of patients (n=109) who underwent completely arterial CABG with the use of the multiple arterial grafts in the same period. RESULTS: LIMA was anastomosed to the left anterior descending coronary artery (LAD) system in all patients. Two to four (mean 2.8+/-0.6) anastomoses were performed with RA Y-graft per patient. Proximal end of the radial graft was anastomosed to LIMA (60.6%) or aorta (39.4%). Mean operating time was 185 (45 min; bypass time, 68+/-23 min; and cross-clamp time, 49+/-17 min). Perioperative intraaortic balloon pump was necessary in five patients (3.9%). There was no operative mortality or morbidity. During the follow-up period of 2-30 months, none of the patients had any complication. Postoperative coronary angiography in 54 patients (42.5%) documented excellent early patency rates (LIMA 100%, and RA 98.1%). CONCLUSIONS: We believe that keeping our technique in their armamentarium will be useful for cardiac surgeons as an alternative method during complete arterial revascularization. This approach allows for complete arterial revascularization in multi-vessel CAD using only single IMA and RA grafts with excellent early results. 相似文献
97.
Witold Kuran Stanisaw Pasynkiewicz Riad Nadir 《Macromolecular chemistry and physics.》1977,178(7):1873-1879
Terpolymerizations of polar vinyl monomers, acrylonitrile, methyl acrylate, or methyl methacrylate with butadiene and styrene in the presence of ethylaluminium dichloride, zinc chloride, or other Lewis acids were carried out. The yield and the contents in monomer units of the terpolymer and the yields of the polar vinyl monomer/butadiene 1,4-cycloaddition byproduct formed in these systems were determined. Butadiene conversions in the above terpolymerizations and 1,4-cycloaddition side reactions were related to those in the copolymerization and 1,4-cycloaddition proceeding in corresponding binary systems without styrene. The results are discussed in terms of a radical polymerization and a polar 1,4-cycloaddition mechanisms. 相似文献
98.
99.
100.
David H. Van Thiel M.D. Abdul Nadir M.D. Tarek Hassanein M.D. Harlan I. Wright M.D. 《The American journal of gastroenterology》1995,90(3):478-481
The medical problems presented by an 83-yr-old man with hepatic amyloidosis complicated by massive ascites and a right hydrothorax are described. As a result of right atrial compression limiting right heart filling, the patient simultaneously experienced left-sided hypovolemia with renal and hepatic ischemia while manifesting signs of right-sided congestive failure. Only with a trans-jugular intrahepatic portosystcmic shunt procedure, which eliminated the right atrial compression with resolution of the hydrothorax and ascites, was it possible to improve the other medical condition of this man. 相似文献