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In the miniature pig MINI-LEWE partial glossectomy had no significant effects on vertical growth of the lower jaw, growth of the upper jaw or overall skull growth. No relationship was found between age at glossectomy or post-surgical interval and the size of the gonion angle. The tongue, peri-oral muscles and the muscles of the floor of the mouth are in a state of functional equilibrium which changes in the course of development, the influence of either the tongue or the peri-oral muscles increasing as a result. Partial disruption of this state of equilibrium leads to dysgnathia.  相似文献   
94.
Nanogram quantities of alpha-fetoprotein (AFP), a tumor associated fetal protein, were found in the serum of normal adult rabbits by radioimmunoassay. This AFP was isolated and shown to be immunologically identical to fetal AFP by immunodiffusion. Immunizations of rabbits with unmodified or desialylated AFP in complete Freund's adjuvant did not cause antibody formation, indicating the existance of tolerance against homologous AFP. The tolerance could be terminated by immunizing with hapten-coupled AFP, which resulted in production of rabbit antibodies reacting with unmodified rabbit AFP.  相似文献   
95.
Left ventricular mass sometimes decreases during treatment of hypertension, but this response is inconsistent and its effects on left ventricular function are unknown. In a six-month randomized trial, we studied the ability of verapamil and atenolol to reduce left ventricular mass in 42 elderly patients with hypertension and the effects of this reduction in mass on cardiac function. The mean blood pressure (+/- SE) decreased in both the group that received verapamil (from 171.4 +/- 3.2/93.0 +/- 2.5 mm Hg to 142.9 +/- 2.8/79.0 +/- 2.0 mm Hg) and the group that received atenolol (from 179.6 +/- 4.6/98.5 +/- 2.4 mm Hg to 148.1 +/- 3.3/83.4 +/- 1.2 mm Hg), but the atenolol-treated patients more frequently required the addition of chlorthalidone to achieve blood-pressure reduction (P less than 0.01). Verapamil resulted in a reduction in the left-ventricular-mass index from 104 +/- 5 g per square meter of body-surface area to 85 +/- 5 g per square meter (P less than 0.01). Atenolol did not produce a reduction in the left-ventricular-mass index (109 +/- 9 g per square meter before treatment vs. 112 +/- 10 g per square meter after treatment). Two weeks after the withdrawal of antihypertensive therapy, blood pressure returned to pretreatment values. Nevertheless, in patients whose left ventricular mass had decreased, two measures of diastolic filling, the peak diastolic filling rate to the peak ejection rate, were significantly higher than before treatment (2.42 +/- 0.2 vs. 3.31 +/- 0.4 [P less than 0.05] and 0.61 +/- 0.03 to 0.85 +/- 0.05 [P less than 0.05], respectively). Diastolic filling was unchanged in the group that had no reduction in left ventricular mass. Cardiac output and the ejection fraction at rest and during mild exercise were unchanged in both groups as compared with baseline values. We conclude that left ventricular mass can be reduced in elderly patients with hypertension and mild ventricular hypertrophy who receive antihypertensive therapy. Reduction occurs more frequently with verapamil than with atenolol therapy, increases diastolic filling, and does not impair systolic function.  相似文献   
96.
Women with complete hydatidiform moles (CHM) are at a 10% risk for developing persistent trophoblastic disease or choriocarcinoma. We studied sister chromatid exchange (SCE) as a prognostic indicator for malignancy in peripheral blood lymphocytes (PBL) from women with CHM and their husbands, but found no differences from normal control couples. SCE levels in cultured tissue derived from 11 CHM (avg. 7.9) and 2 choriocarcinomas (avg. 6.8) were not significantly different from those of 8 normal skin fibroblast cultures (avg. 7.8). These same tissues were then examined for chromosome breakage which was significantly higher for CHM (0.48/cell) and choriocarcinoma (0.87/cell) than normal fibroblasts (0.33/cell). Chromosome breaks occurred at 50-60% known fragile sites and at 50-55% of cancer breakpoints. Whereas SCE was only associated with 13% of breaks in the three tissues, half of these were at known fragile sites. Our results suggest that SCE is not an indicator of malignancy in PBL or cultured cells from CHM or choriocarcinoma and that the level of SCE is not elevated in CHM or choriocarcinoma. However, our results confirm the increased breakage seen in the latter two tissues which may represent general DNA instability predisposing to choriocarcinoma and its accompanying chromosomal rearrangements.  相似文献   
97.
In-frame deletions from the E-cadherin mRNA, coding for a homophilic cell adhesion molecule, are characteristic for diffuse-type gastric carcinomas. Using immunohistochemical analysis the mutant form cannot be distinguished from normal E-cadherin, making results difficult to interpret. In this study, a rat monoclonal antibody, designated E-cad delta 9-1, was generated against a peptide spanning the fusion junction region between exons 8 and 10. This new epitope is present in an E-cadherin variant that lacks exon 9 from the mRNA due to different splice-site gene mutations. Using Western blotting and immunohistochemistry of E-cadherin-transfected cells, we demonstrate that E-cad delta 9-1 specifically reacts with E-cadherin lacking exon 9 but not with the wild-type protein. No immunoreactivity was observed in 31 nontumorous and embryonal tissues analyzed. In gastric carcinoma specimens known to express mutant E-cadherin mRNA lacking exon 9, E-cad delta 9-1 targets exclusively tumor cells in routine formalin-fixed and paraffin-embedded material from biopsies, primary tumors, and lymph node metastases. In a retrospective series of 172 diffuse-type gastric carcinomas expressing E-cadherin, E-cad delta 9-1 reacted with 22 tumors (13%). This new tumor marker-monoclonal antibody system could open novel avenues for selective diagnosis and specific therapy of a subgroup of diffuse-type gastric cancer patients.  相似文献   
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Psyllium is a hydrophilic agent found in many bulk laxative preparations. We report the occurrence of an anaphylactic reaction in a patient after ingestion of a psyllium-containing laxative. IgE mediation of the reaction was suggested by a positive immediate skin test to psyllium, positive passive transfer skin test, lack of skin response during passive transfer with heat treated serum, and an elevated IgE (RAST) to psyllium seed.  相似文献   
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