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To demonstrate the presence of independent genetic determinants of multiple correlated tooth dimensions from twin data, a multivariate analysis was performed on the covariance matrices of monozygotic and dizygotic within-pair differences for mesiodistal and buccolingual dimensions of 28 teeth of the secondary dentition. The results provided strong evidences that the correlation among tooth dimensions is primarily genetic in origin, probably attributable to the pleiotropic action of either independent genes or groups of genes. Among the genetic factors that were identified, one appeared to affect the maxillary teeth in general while a second influenced primarily the anterior mandibular teeth. There was a striking tendency for homologous measurements on the right and left sides to be associated with the same genetic factor. In contrast, genetic determination of the maxillary and mandibular dentition seemed to be independent of each other, and a wider range of genetic factors were found to influence the mandibular than the maxillary teeth, suggesting that a differential degree of evolutionary stability may have been achieved in the teeth of the two jaws.  相似文献   
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Nonsuppressible insulin-like activity, provided by three sources, was evaluated for its effect on the proteolytic degradation of insulin utilizing insulin protease obtained from rat liver homogenate as well as liver cell membranes. All three preparations of nonsuppressible insulin-like activity were found to be competitive inhibitors of insulin degradation. In addition human plasma was fractionated yielding an acetone precipitate which was found to have nonsuppressible insulin-like activity and to be a competitive inhibitor of insulin protease.  相似文献   
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L-Tryptophan, L-tryptophanylglycine, glycyl-L-tryptophan, glycyl-L-tryptophanylglycine and glycyl-L-tryptophanylglycylglycyl-L-tryptophanylglycine have been transferred from an aqueous solution (generally 0.1 M NaOH) to cyclohexane, using the quaternary ammonium salt trioctylmethyl ammonium chloride (NR+4Cl-, soluble in cyclohexane but not in water) as the transporting agent. The spectroscopic properties of L-tryptophan and tryptophan-containing peptides have been studied in the cyclohexane phase. With respect to the aqueous solutions, ultraviolet absorption spectra are characterized by a considerable red shift of the absorption maxima and by a hypochromicity of up to 10%. Fluorescence spectra generally show emission maxima which are characteristic of polar environments, accompanied by a significant enhancement of the quantum yield. CD spectra have also been investigated for all peptides and compared with those for aqueous systems reported in preceding publications. All these spectral changes cannot be attributed solely to the cyclohexane solvent effect. It is suggested that these anomalous spectral properties of the tryptophan-containing compounds in the cyclohexane-NR+4 solution are due to the influence the electrostatic field of the ion pair has on the indole chromophore. The possible implications of this finding for the spectroscopic properties of aromatic residues buried in the polar interior of proteins are discussed.  相似文献   
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The primary goal in the medical management of ventricular septal defect complicating myocardial infarction is to support cardiac function and control symptoms, if possible, for a period of 4 to 6 weeks. If the patient survives this period, surgical correction of the defect is technically easier and safer. In many cases, However, cardiac function is severly compromised, intractable biventricular failure develops,early operation is necessary and the likelihood of successful repair is diminished.  相似文献   
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From 1978 to 1990 inclusive more than 1,200 patients above 70 years of age have been treated surgically for a hip fracture at the University Hospitals of Leuven. Intracapsular fractures were classified as to Garden and extracapsular fractures as to Evans. The physical and mental conditions of the patients at the time of the accident were largely determining the choice of the treatment, a treatment that held quo ad vitam only little risk for the patient and that permitted early weight bearing on the operated limb. We concluded that: Stable intracapsular fractures have to be treated with simple cancellous bone screws. For unstable intracapsular fractures, a total hip prosthesis is the best solution; hemiarthroplasty must be reserved for high risk patients with a limited life expectancy. Nearly all type 1 pertrochanteric fractures can be treated with a (modified) dynamic hip screw technique. Prosthetic surgery is only indicated in very complex type 1d fractures. For type 2 fractures, the gamma-nail is (may be) the best solution.  相似文献   
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In response to cardiac ischemia/reperfusion, proteolysis mediated by extracellular matrix metalloproteinase inducer (EMMPRIN) and its secreted ligand cyclophilin-A (CyPA) significantly contributes to cardiac injury and necrosis. Here, we aimed to investigate if, in addition to the effect on the funny current (I(f)), Ivabradine may also play a role against cardiac necrosis by reducing EMMPRIN/CyPA-mediated cardiac inflammation. In a porcine model of cardiac ischemia/reperfusion (IR), we found that administration of 0.3 mg/kg Ivabradine significantly improved cardiac function and reduced cardiac necrosis by day 7 after IR, detecting a significant increase in cardiac CyPA in the necrotic compared to the risk areas, which was inversely correlated with the levels of circulating CyPA detected in plasma samples from the same subjects. In testing whether Ivabradine may regulate the levels of CyPA, no changes in tissue CyPA were found in healthy pigs treated with 0.3 mg/kg Ivabradine, but interestingly, when analyzing the complex EMMPRIN/CyPA, rather high glycosylated EMMPRIN, which is required for EMMPRIN-mediated matrix metalloproteinase (MMP) activation and increased CyPA bonding to low-glycosylated forms of EMMPRIN were detected by day 7 after IR in pigs treated with Ivabradine. To study the mechanism by which Ivabradine may prevent secretion of CyPA, we first found that Ivabradine was time-dependent in inhibiting co-localization of CyPA with the granule exocytosis marker vesicle-associated membrane protein 1 (VAMP1). However, Ivabradine had no effect on mRNA expression nor in the proteasome and lysosome degradation of CyPA. In conclusion, our results point toward CyPA, its ligand EMMPRIN, and the complex CyPA/EMMPRIN as important targets of Ivabradine in cardiac protection against IR.  相似文献   
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