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71.
72.
Ninety-two patients with Dukes' class C colonic carcinoma, divided equally into those who survived 5 years or more and those surviving less than 5 years after resection for cure, underwent evaluation of multiple histopathologic characteristics of the primary tumor and the uninvolved regional lymph nodes. These characteristics were analyzed by the chi-square test for correlation with survival. A statistically significant correlation (P less than 0.05) in the group who survived 5 years or more was observed for Broders' grades 1 and 2, tumor not involving serosa, and a pushing tumor margin. Of the 14 patients who had a pushing tumor margin and tumor not involving serosa, 12 (86%) survived 5 years or more. Seven patients had an infiltrating tumor margin and peritumor venous invasion, and of this group, only one (14%) survived 5 years or more. Histopathologic characteristics of host immune reaction at the tumor or in the uninvolved regional lymph nodes did not correlate with survival. 相似文献
73.
CG Fellin G Briani G Baggio E Manzato R Veronese 《Canadian Metallurgical Quarterly》1977,26(4):593-602
The prevalence of coronary artery disease (CAD) and peripheral artery disease (PAD) was studied in 280 (203 males, 77 females) patients with different types of primary hyperlipoproteinemia. In primary hyperbetalipoproteinemia the prevalence of CAD (45% for Type IIa and 47% for Type IIb) is significatly higher than that in the other types of hyperlipoproteinemia (38% for Type IV and 17% for Type V). On the other hand, PAD prevalence is much higher in hypertriglyceridemia (21% in Type IIb and 20% in Type V) than in hypercholesterolemia alone (9% in Type IIa). These results suggest ths atherosclerotic complications are concerned. Moreover, the high frequency of PAD found in hypertriglyceridemia can be related to the high occurrence of diabetes in these patients. The effects of other major risk factors of atherosclerosis (smoking and hypertension) were also evaluated. Our results indicate that the association of hypercholestolemia and hypertension is more dangerous than the co-occurence of hypercholesterolemia and smoking. 相似文献
74.
The enzyme ornithine decarboxylase (L-Ornithine carboxy-lyase, EC 4.1.1.17), has been partially purified from the livers of mice subjected to partial hepatectomy (6-8 h previously). Mouse liver ornithine decarboxylase requires pyridoxal phosphate, and dithiothreitol for maximal activity. The enzyme has a pH optimum of 7.3, it is inhibited in the presence of 0.3 M phosphate, glycine, Tricine and Tris. It shows no dependence on metal ions and is inhibited by high salt concentrations, particularly ammonium salts. The kinetics of the enzyme have been studied with putrescine (and analogs), spermidine and spermine, in the presence of both high and low levels of pyridoxal phosphate. High concentrations of pyridoxal phosphate inhibit the enzyme. The enzyme is also inhibited by low concentrations of putrescine (1 mM). As the concentration of putrescine increased to 10 mM, non-competitive inhibition was observed, this could be reversed by addition of higher levels of pyridoxal phosphate. Spermidine and spermine inhibit (noncompetitively) only at high concentrations (10 mM). Ornithine inhibits at high concentrations (2 mM). Spectral studies have shown that the observed kinetics of competitive inhibition at low concentrations of polyamine changing to noncompetitive inhibition at high polyamine concentrations are due to competition between enzyme and substrate (or inhibitor) for free (non-enzyme bound) pyridoxal phosphate. Noncompetitive inhibition arises through the formation of transient Schiff base complexes between amines and free pyridoxal phosphate. It also appears that the binding of substrate to the active site takes place through Schiff base formation with enzyme bound pyridoxal phosphate. 相似文献
75.
CG Watson 《Canadian Metallurgical Quarterly》1976,31(5):611-616
Eighty-four geriatirc ward patients were randomly assigned to groups targeted for outplacement planning or inpatient care. During the following year, half of the former were placed in community settings while nearly all of the latter remained in the hospital. Neither the physical health, level of self-care, or psychiatric condition ratings of the two groups changed differentially over that time. However, the mean Morale Inventory score of the outplacement sample improved while that of the in-patient group remained static. Additional analyses were run between three groups - outplacement planning subjects who were released, those who were not released, and inpatient planning men who were not released. These results confirmed those of the first analyses; the only significant difference appeared on the Morale Inventory, the patients who left showing more improvement than the other two groups. The results argue for an increased emphasis on outplacement programs among geriatric patients. 相似文献
76.
A container to hold specimens during dehydration and critical point drying can be constructed from a 100 mesh screen cylinder and a BEEM embedding capsule. 相似文献
77.
78.
Rychlak Joseph F.; McKee Douglas B.; Schneider William E.; Abramson Yitzchok 《Canadian Metallurgical Quarterly》1971,77(3):247
Reports 3 studies on the influence of idiographic affective judgments of likability on the learning of CVC trigram materials among a total of 36 normals and 68 abnormals. The construct under study was termed reinforcement value (RV). It was hypothesized that whereas normals have been shown to acquire materials they judge to be positive more readily than those they judge to be negative in RV, an "RV-reversal" should be the case for abnormals. Findings on abnormals (primarily schizophrenics) were not unequivocably in line with an RV-reversal effect, but there was evidence in cross-validation to suggest that an abnormal learning style places less emphasis on acquisition of liked over disliked materials. A theory of learning based upon tautology is presented as explanatory of the findings. (28 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
The occurrence and distribution of adrenergic and acetylcholine esterase (AChE) positive nerves in the human urethra and urinary bladder were studied histochemically with the fluorescence method of Falck and Hillarp, and the copper thiocholine method of Koelle and Friedenwald. Both types of nerves were mainly confined to the layers of smooth muscle cells in the walls of the organs. In all parts of the urethra, there was a scanty supply of adrenergic nerves. Few adrenergic nerves were also found in the urinary bladder, except in the trigone area, where they were abundant. AChE-positive nerves were uniformly and richly distributed in the urinary bladder. Throughout the urethra the distribution of AChE-positive nerve fibres was uniform, but the number was clearly less than in the urinary bladder. No intrmurally located adrenergic or AChE-Positive ganglion cells could be demonstrated. 相似文献
80.
Peper S Qin Y Almond P McKee M Telting-Diaz M Albrecht-Schmitt T Bakker E 《Analytical chemistry》2003,75(9):2131-2139
Recently, it has been discovered that carba-closo-dodecaborates can be used as cation exchangers in neutral carrier-based ion-selective chemical sensors. Because of their inherent chemical stability and versatile functionalization chemistries, they offer many advantages that may potentially be exploited for ion analyses that require nontraditional sample conditions, including strongly acidic media. In this work, trimethylammonium salts of undecachlorinated (UCC), undecabrominated (UBC), hexabrominated (HBC), and undecaiodinated (UIC) carborane anions were prepared and evaluated for their potential use in solvent polymeric membrane-based sensors. Computational methods including Natural population analysis and electrostatic mapping were used to predict the ion-exchanging ability of each lipophilic anion. In addition, the sandwich membrane technique was used to evaluate the ion-pairing ability of each carborane anion in situ (i.e., within bis(2-ethylhexyl) sebacate (DOS)- and 2-nitrophenyl octyl ether (o-NPOE)-plasticized ISE membranes). The results of the computational and potentiometric studies found that binding affinity of the anions followed the generalized trend HBC > UCC > UBC > UIC. PVC-DOS bulk optode thin films containing the chromoionophore ETH 5315 and a respective anion were used to determine the chemical stability/lipophilicity of the carboranes and tetrakis[3,5-bis(trifluoromethyl)phenyl] borate (TFPB) in acidic media (0.2 M HOAc) under flowing conditions. The studies found that in terms of stability/lipophilicity UIC > UBC > TFPB approximately UCC > HBC. Electrodes containing a Pb(2+)-selective ionophore, tert-butylcalix[4]arene-tetrakis(N,N-dimethylthioacetamide)(lead IV), were used to evaluate the functionality of each cation exchanger. An evaluation of response characteristics such as slope and selectivity found that UIC and UBC were quite comparable to the behavior of TFPB. Interestingly, both UIC and UBC showed a marked selectivity improvement over cadmium, with log K(pot)(pb),(Cd) values of -7.19 and -7.29, respectively, with TFPB giving a value of -5.89. Demonstrating excellent stability and suitable electrostatic properties, the carboranes, UIC in particular, are a very promising alternative to the tetraphenylborates and should find widespread application in the field of chemical sensors. 相似文献