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991.
992.
Vessel wall matrix changes occur after injury, although this has not been well studied in the venous system. This study tested the hypothesis that the thrombus dictates the vein wall response and vein wall damage is directly related to the duration of thrombus contact. To determine the injury response over time, rats underwent inferior vena cava (IVC) ligation to produce a stasis thrombus, with harvest at various time points to 28 days (d). Significant vein wall matrix changes occurred with biomechanical injury (stiffness) peaking at 7-14 d, with concurrent early reduction in total collagen, an increase in early matrix metalloproteinase (MMP)-9 and late MMP-2, and concomitant increase in tumor necrosis factor (TNF)alpha, monocyte chemoattractant(MCP)-1 and tumor growth factor (TGF)beta (all P<0.05). To isolate the effect of the thrombus and its mechanism of genesis, rats underwent 7 d or limited stasis (24 hours), non-stasis thrombosis, or non-thrombotic IVC occlusion (Silicone plug). Vein wall stiffness was increased seven-fold, with a five-fold reduction in collagen, and 5.5- to seven-fold increase in TNFalpha, MCP-1, and TGFbeta with 7 d stasis as compared with controls (all P<0.05). By Picosirus red staining analysis, collagenolysis was significantly greater with 7 d stasis injury (P=0.01) but neither MMP-9 nor MMP-2 activity correlated with injury mechanism. In addition, vein wall cellular proliferation and uPA gene expression paralled the stasis thrombotic injury. Limited stasis, non-stasis thrombosis and non-thrombotic IVC occlusion showed a lesser inflammatory response. These data suggest both a static component and the thrombus directs vein wall injury via multiple mechanisms.  相似文献   
993.
The severe functional deficits in patients suffering from traumatic peripheral nerve damage underline the necessity of an optimal therapy. The development of microsurgical techniques in the sixties contributed significantly to the progress in nerve repair. Since then, no major clinical innovation has become established. However, with an increased understanding of cellular and molecular mechanisms underlying nerve regeneration, various tubulization concepts have been developed which yield possible alternatives to direct suturing and to autologous nerve grafting in cases of short nerve defects. The vast knowledge gathered in the field of nerve regeneration needs to be further exploited in order to develop alternative therapeutic strategies to nerve autografting, which can result in donor-site defects and often lead to inappropriate results. Considering the encouraging results from preclinical studies, innovative nerve repair strategies are likely to improve the outcome of reconstructive surgical interventions. This paper outlines, in addition to the fundamentals of nerve regeneration, the current treatment options for defects of peripheral nerves. This article also reviews the developments in the use of alternative nerve guides and demonstrates new perspectives in the field of peripheral nerve reconstruction.  相似文献   
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Intraperitoneal injections of chlordiazepoxide in rats attenuated the severity of stomach ulcers induced by a single restraint session. However, when the drug was withheld during the last session of a series of repeated restraint treatments, stomach erosions developed in the animals. Vehicle-controls, on the other hand, had adapted to the chronic stress, as indexed by a decline in gastric pathology. The results were discussed in reference to stress adaptation and drug withdrawal effects.  相似文献   
998.
Specific and saturable binding sites of the synthetic human calcitonin gene-related peptide-I (CGRP-I) and -II (CGRP-II) have been identified in membrane homogenates of the human central nervous system, heart and spleen. Half maximal inhibition of the binding of125I-CGRP-II was achieved with 0.25 nM and 1.7 nM of non-radioactive CGRP-I or -II, and with 260 and 850 nM salmon calcitonin in the spinal cord and cerebellum, respectively, but 1 μM human calcitonin was not recognized. Autoradiographs of diencephalic sections revealed different distribution of125I-CGRP-I and -II binding sites.  相似文献   
999.
Autologous blood (collected preoperatively or salvaged intraoperatively) is the safest blood available for transfusion, but its use is not always feasible. It may be possible to decrease a patient's exposure to homologous donors. Pediatric cardiac surgery patients frequently are unable to donate autologous blood preoperatively. Since 1984, attempts have been made to provide parental apheresis platelets and intraoperative blood salvage to such patients to decrease their donor exposure. Further decreases in donor exposure have been the object of a program of collecting from one committed donor all the blood a patient is anticipated to need. This article reviews the experience with 50 pediatric cardiac surgery patients on such a program, in whom the mean decrease in homologous-donor exposure was 57 percent (range, 12-93%). Thirteen of these patients received only homologous blood products from one committed donor, for a mean decrease in homologous-donor exposure of 80 percent (range, 50-93%). A comparison of 12 of these 13 recipients with a matched control group showed no significant difference in red cell transfusion practice but a significant difference in the number of homologous-donor exposures per m2 of body surface area (BSA) (mean donor exposures/m2 of BSA: patients = 1.5, controls = 10.5). The use of one committed donor and autologous blood can provide a minimal-exposure transfusion.  相似文献   
1000.
Lymphangioma or cystic hygroma is an uncommon benign congenital tumor of lymphatics that is seen in children and, rarely, adults. Lymphangioma primarily involving the parotid gland is an extremely uncommon occurrence in adults. We report on the cytologic findings of a parotid lymphangioma in a 34-yr-old man which showed 13 cc of yellow fluid with red blood cells, lymphocytes, and rare fragments of benign-appearing salivary gland epithelium. The differential diagnosis of cystic parotid gland lesions in adults may include Warthin's tumor, lymphoma, benign lymphoepithelial lesions, branchial cleft cysts, chronic sialadenitis, cystic low-grade mucoepidermoid carcinoma, and cystic pleomorphic adenoma. In this case, the fine-needle aspiration findings along with the magnetic resonance imaging (MRI) findings of a multiloculated cystic mass in the parotid gland allowed the diagnosis of lymphangioma.  相似文献   
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