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991.
Increased prostaglandin production is a possible mechanism for the immunosuppressive effects of both cyclosporine and blood transfusions. Therefore, dietary supplementation with linoleic acid, a prostaglandin precursor, combined with either modality could act synergistically. Intraabdominal cardiac allografts were performed from Buffalo rat donors to Lewis recipients. Transplant recipients received a single donor-specific transfusion, low-dose cyclosporine (CsA, 1 mg/kd/d x 7 days), dietary supplementation with linoleic acid (LA, 16% of total calories) or a combination of the three modalities. CsA, DST or LA alone significantly prolonged allograft survival. Both CsA and LA acted synergistically with DST in further prolongation of survival--however, animals receiving all three modalities achieved 100% long-term survival. Augmentation of transfusion- and cyclosporine-induced immunosuppression with dietary prostaglandin precursor is possible.  相似文献   
992.
C A Perez  S Breaux  F Askin  H M Camel  W E Powers 《Cancer》1979,43(3):1062-1072
This is a report of a nonrandomized comparison of treatment results of 244 patients with stage IB carcinoma of the uterine cervix treated by radiation alone and 92 treated with preoperative radiation and surgery and 77 patients with stage IIA treated by radiation alone and 24 treated with a combination of radiation and surgery. The techniques of irradiation and types of operation are described in detail. The five-year tumor free actuarial survival for the patients with stage IB treated either with irradiation alone or combined with surgery was approximately 85% and the ten-year survival, 78%. For stage IIA the tumor free actuarial five-year survival without tumor was 73% and for ten years, 60%. In the 244 patients treated with radiation alone, there were ten central failures (4%) usually combined with distant metastasis. Further, 16 of these patients (6.5%) developed parametrial recurrence, in all but one instance associated with distant metastasis. In the 92 patients with stage IB treated with combined therapy, there were three local recurrences (3.8%), two of them combined with parametrial failures and six parametrial recurrences (6.5%), all of them concomitant with distant metastasis. Of the 77 patients with stage IIA treated by irradiation alone, there was one central recurrence alone and five local and parametrial recurrences, all of them associated with periaortic nodes or distant metastasis. Four additional patients had parametrial recurrences only concurrent with distant metastasis. Of the 24 patients treated with irradiation and surgery, there were two parametrial recurrences combined with distant metastasis (8.2%). There was no significant difference in the survival or recurrence rate of the patients treated with either method. In the group treated with combined therapy, patients with stage IB who showed evidence of microscopic residual tumor after irradiation had a failure rate of approximately 42% (8/18) in contrast to only 8.6% (6/70) in those with negative specimens. In stage IIA there were three failures in eight patients with residual tumor in the specimen in contrast to only two of 16 with negative specimens (12.5%). Major complications were comparable in both groups (radiation alone approximately 8.7% and irradiation combined with surgery approximately 14%), the difference is not statistically significant. The most frequent minor complication in patients treated with radiation alone was vaginal fibrosis (30 patients--9%) or vaginal vault necrosis (10 patients--3%).  相似文献   
993.
994.
G L Perez  A A Luisada 《Angiology》1976,27(5):300-310
A study of the fourth sound was conducted on 100 normal subjects (ages 1-88 years) and 42 clinical cases with either aortic stenosis, systemic hypertension or coronary heart disease. This study was based on the graphic recognition of a presystolic sound when the tracing was taken with the use of one or more of 5 different high pass filters. Attention was paid to the existence of the fourth sound, its magnitude, and its vibrational frequency. In general it was accepted that a magnitude of 1/2 of the first heart sound or a frequency of 30 Hz denoted a pathologic fourth sound. However, exceptions were found among normal subjects, so that only the combination of the two criteria could be considered highly significant for a pathologic phenomenon (gallop). Patients with aortic stenosis presented an increase in magnitude of the fourth sound but incidence and vibrational frequency were similar to those of controls. Patients with hypertension had a greater incidence of fourth sounds, especially in middle age (100%); middle age patients usually had a greater magnitude while older patients had more often an increase in vibrational frequency. Patients with coronary heart disease (evidence of old infarcts) had an increase in the incidence, magnitude, and vibrational frequency in comparison with controls. These data and the cause of the fourth sound are discussed. The fourth sound has been repeatedly studied in the past, both as an auscultatory finding and a graphic phenomenon. Attempts were made for separating the normal fourth sound from that denoting a pathological phenomenon but, so far, no clear cut criteria for the differentiation have been obtained. We thought, therefore, that a new study was indicated.  相似文献   
995.
Metabolic acidosis is known to be associated with increased blood potassium and phosphorus concentrations but the influence of mineral versus nonmineral acids on these variables remains undefined. Therefore, we infused anesthetized mongrel dogs with 0.45% saline (controls), the mineral acids HCl and NH4Cl, and the nonmineral acids lactic, beta-hydroxybutyric and methyl malonic for 1-3 h. Administration of both mineral acids was associated with significant increases in plasma potassium. In contrast, infusion of the three monmineral acids did not result in increases in plasma potassium; in fact, the levels decreased initially in the majority of the dogs. Phosphorus concentrations were increased by lactic and beta-hydroxybutric acids, were unchanged by NH4Cl and HCl, and were decreased by methyl malonic acid. Although the mechanisms responsible for these changes remain to be elucidated, the findings indicate that short-duration infusion of mineral and nonmineral acids has substantially different effects on plasma concentrations of these predominantly intracellular ions.  相似文献   
996.
Summary Polyelectrolytes and protein molecules appear to be able to act not only as crystallization inhibitors when present in solution, but also as promoters of crystal growth when immobilized onto surfaces. Because this is especially relevant for systems in which heterogeneous nucleation can occur, the influence of poly-L-glutamic (PGlu) acid, poly-L-aspartic (PAsp) acid, and human serum albumin (HSA) on the nucleation and growth inhibition of calcium oxalate monohydrate (COM) was studied using the Constant Composition (CC) kinetics technique. The overgrowth of COM on hydroxyapatite (HAP) seed crystals pretreated with HSA was also investigated. Pronounced differences in inhibiting and nucleating potential were found for the various additives. HSA, a relatively poor growth inhibitor when present in solution, was found to nucleate very regular, hexagonal COM crystals when immobilized on a surface and to enhance the overgrowth of COM when adsorbed on HAP surfaces.  相似文献   
997.
998.
999.
1000.
The clinical, light, and ultrastructure features of a myoepithelioma occurring on the hard palate of a 24-year-old woman are presented and compared with 41 myoepithelioma of the head and neck described in the English literature. These 42 tumors (39 benign and 3 malignant) occurred in individuals from 14 to 81 years of age, affected both sexes about equally, and most often presented as a slowly enlarging, asymptomatic mass. The parotid gland and palate were the most common sites of occurrence. The tumors are typically circumscribed and encapsulated, vary from 1 to 5 cm in the greatest dimension, and are composed of spindled and/or plasmacytoid myoepithelial cells. Prognosis correlates with histologic appearance and parallels that of the pleomorphic adenoma. Conservative excision with a margin of uninvolved tissue is curative. The differential diagnosis and histogenic relationship with other closely related neoplasms are discussed.  相似文献   
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