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991.
992.
It is well known that fibroblasts are a main source of extracellular matrix synthesis necessary for tissue repair. In addition, macrophages secrete products that are known to modulate synthesis of extracellular matrix. Accordingly, we studied the incorporation of [3H]thymidine, [3H]proline, and [35S]sulfate into macromolecules produced by fibroblasts recovered from the site of peritoneal tissue repair cultured with and without spent media from postsurgical peritoneal macrophages. Rabbits underwent resection and reanastomosis of their small intestines. Peritoneal exudative cells (PEC) were then collected on postsurgical day 5 and day 10 as well as from nonsurgical controls, separated by discontinuous Percoll gradient centrifugation, and cultured for 48 h. A second group of rabbits underwent peritoneal wall abrasion from which fibroblast tissue repair cells (TRC) were collected from the site of injury at postsurgical day 7 and maintained in culture for varying times. Incorporation of radiolabeled precursors into DNA, collagen, and sulfated proteoglycans was determined. Incorporation of [3H]thymidine and [3H]proline into untreated TRC gradually decreased with culture duration. Conversely, [35S]sulfate incorporation gradually increased during prolonged culture. Macrophage spent media increased the levels of [3H]thymidine incorporation by the TRC. [3H]Proline and [35S]sulfate incorporation into TRC were also stimulated by macrophage spent media. However, this stimulation may be due to the enhanced proliferation of TRC by macrophage spent media. In conclusion, tissue repair fibroblasts are activated for postsurgical repair at the site of injury by many factors including secretory products from postsurgical macrophages.  相似文献   
993.
The myopathies that can manifest themselves within the lower extremity are reported here and can serve as a guideline for clinicians in the early diagnosis of these disabling conditions. The classification of these disease entities based on signs and symptoms is significant if correlated with the age of the patient at the time of onset, the evolution and course, and the type of familial inheritance. This article can also aid the practitioner in assessing and planning the course of treatment for a particular patient.  相似文献   
994.
A study has been carried out on the possible pharmaceutical use of spanish talcs following the normalized assays of the main european pharmacopoeia and other quantitative methods. Only the talc nr3, not processed, meets all the assays of pharmacopoeia. The samples 2 and 4 (crushed) exceed the highest tolerated content in chlorides. The talc 1 (also crushed) only meets the loss on drying. The measures of some of these assays by using quantitative methods lead to more correct results and even sometimes in opposition with those obtained by pharmacopoeia methods. The particle size estimated by shifting and sedimentation shows that the crushed talcs are silty, whereas the only talc not processed is sandy. Considering the medium sizes estimated by scanning microscopy, it can be said that the pulverization of the talcs 1, 2 and 4 is characteristic of a micronization.  相似文献   
995.
In open chest dogs myocardial ischemia was induced by formation of an occlusive thrombus in the left anterior circumflex artery (LCX). Reperfusion of the LCX was achieved by infusion of the fibrin specific recombinant single-chain urokinase-type plasminogen activator (r-scu-PA). The myocardial salvage by r-scu-PA alone and in combination with the epoprostenol (prostacyclin) analog taprostene (CG 4203) was compared. There were four experimental groups: group 1 (n = 4) did not receive any treatment after LCX thrombosis; in group 2 (n = 9) at 100 min after LCX thrombosis r-scu-PA (20 micrograms.kg-1.min-1 i.v. for 30 min) was infused; in groups 3 and 4 treatment with taprostene started concomitantly with r-scu-PA infusion. The taprostene infusions lasted for 120 min and the doses were 0.1 microgram.kg-1.min-1 in group 3 (n = 6) and 0.215 microgram.kg-1.min-1 in group 4 (n = 6). Time to r-scu-PA-induced recanalisation ranged from 18-22 min with no significant difference between groups 2-4. Percent of left ventricle at risk did not differ between the groups. Infarct size as percent of the risk zone was 48.3 +/- 7.7 in group 1, 25.3 +/- 3.7 in group 2, 21.3 +/- 6.5 in group 3 and 17.1 +/- 3.5 in group 4 (p less than 0.05 groups 2-4 vs group 1). Incidence of ectopic beats increased after r-scu-PA-induced reperfusion in groups 2-4, but was significantly reduced by taprostene.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
The extent to which repeated administration produces tolerance to nicotine-induced increases in dopamine transmission in the nucleus accumbens was investigated in rats. In vivo microdialysis was used to sample extracellular dopamine and metabolites after a nicotine challenge (0.35 mg/kg) in (1) naive rats, (2) acutely pretreated rats (1 prior nicotine injection), and (3) chronically pretreated rats (12-15 prior daily nicotine injections, 0.35 mg/kg per injection). Nicotine increased extracellular DA and its metabolites, and these increases were not significantly altered by either acute or chronic prior exposure to the drug. The failure to find evidence of tolerance is compatible with the hypothesis that the mesolimbic dopaminergic system is a substrate for the reinforcing properties of chronically administered nicotine.  相似文献   
997.
998.
999.
A total of 42 patients with recurrent superficial bladder tumors or carcinoma in situ entered a prospective, randomized trial to compare the efficacy of bacillus Calmette-Guerin therapy with and without quarterly maintenance instillations of bacillus Calmette-Guerin. Maintenance therapy did not reduce further bladder tumor recurrence rates or the interval to recurrence in patients who responded to the initial course of therapy. However, prolongation of toxicity was observed with maintenance bacillus Calmette-Guerin therapy.  相似文献   
1000.
In the brain of quaking and shiverer mutants, vitamin E content was normal when related to both wet weight and dry weight. When related to lipid extract, phosphorus, and polyunsaturated fatty acids, vitamin E was slightly increased only in the quaking mutant. In the sciatic nerve from trembler mutants, vitamin E was 134% of control values in the dry material, but normal in relation to wet weight. It was 260% in the lipid extract and 716% based on phosphorus. In relation to total fatty acids, there was a threefold increase in trembler mutants. Interestingly, it was increased approximately three times when related to 18∶2 n?6, 20∶4 n?6, and 20∶5 n?3, and seven times when related to 22∶6 n?3. The fact that the amount of vitamin E in fresh weight was normal, suggests that vitamin E plays a role in some nonmembrane material, such as the extracellular matrix or the basal lamina.  相似文献   
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