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971.
972.
Thirty-eight patients with squamous cell carcinoma of the soft palate treated between 1960 and 1975 were reviewed. Males in the seventh decade predominated. All symptomatic patients complained of sore throat and/or odynophagia. Seventy-eight percent were symptomatic less than three months. Approximately equal numbers of patients presented with T1, T2, and T3 tumors. Twenty-seven percent had cervical metastases when initially seen. The majority (89%) of patients were treated with radiation initially and the remainder (11%) received radiation therapy at the time of postsurgical recurrence with an absolute five year survival of 33%. Patients less than 60 years of age and those with small primary tumors and no neck metastases demonstrated better survival. Radiation therapy to the primary tumor and neck appears to be the preferred modality of initial treatment.  相似文献   
973.
The high pressure crystallized specimens described in the preceding paper (1) were characterized by X-ray diffraction, density, and differential scanning calorimetry, Nitric acid etching, followed by gel permeation chromatography and DSC on the residues provided further characterization of the morphology. The crystallinity decreased from 100 to 80 percent with increasing molecular weight, over the range Mw = 4.9 × 104 to 4.6 × 106. The crystallites were predominately in extended chain morphology, but the percent in extended chain form decreased from 98 to 85 percent over the indicated molecular weight range. In all cases, there was a wide, bimodal or multi-modal, distribution of lamellar thickness. The physical characterization results were consistent with and complementary to the results from electron microscopy. The large differences in crystallinity and gross morphology readily account for observed molecular weight dependent differences in mechanical properties.  相似文献   
974.
A review is presented of vesical-related paragangliomas and 3 cases are reported. Methods for early diagnosis, including selective angiographic demonstration, and treatment of these rare tumors are discussed. A multi-team approach by the urologist, endocrinologist and anesthesiologist is stressed for better control of potentially dangerous vasomotor changes during diagnosis and surgical treatment of this tumor.  相似文献   
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The ability of macrophages of phagocytize particulate matter is largely dependent on fibronectin, a nonspecific opsonin found in plasma. Fibronectin depletion, resulting in reticuloendothelial system (RES) depression, occurs following a variety of physical insults. RES depression may contribute to postinjury sequelae such as respiratory distress syndrome and septicemia. Fibronectin concentration was measured in the plasma of sheep with chronic lung lymph fistulas subjected to controlled thermal injury. Fibronectin levels were significantly (p < 0.05) decreased at 4, 24, 48, and 72 hours following burning. Fibronectin concentration decreased in parallel with serum albumin concentration; serum globulin concentrations did not decrease. Fibronectin concentration had an inverse relationship to lung lymph flow, a reflection of pulmonary transvascular fluid filtration rate. The role of fibronectin in the pathogenesis of postinjury respiratory distress syndrome deserves further exploration.  相似文献   
979.
MMP, a linear alpha 1 leads to 4 linked polymer of 3-O-methylmannose, regulates the fatty acid synthetase from Mycobacterium smegmatis by forming stoichiometric complexes with the long-chain acyl-CoA synthetase products. In agreement with previous proposals [Bloch, K. (1977) in Advances in Enzymology and Related Areas of Molecular Biology, ed. Meister, A. (Wiley, New York), Vol. 45, pp. 1-84], nuclear magnetic resonance studies show that the polysaccharide, a random coil in its free form, undergoes a major conformational transition upon enclosing long-chain acyl-CoA. The polysaccharide, probably in helical conformation in the complexed form, interacts with both the paraffinic chain and the CoA moieties of the included fatty acyl thioester.  相似文献   
980.
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