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91.
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In a series of 68 patients with gastric ulcer who were treated by vagotomy and pyloroplasty there were no operative deaths, though one patient who received massive transfusions died 14 weeks later from hepatic necrosis probably associated with serum hepatitis. Four patients developed recurrent peptic ulceration requiring further surgical treatment. The clinical condition of all but three of the remainder was satisfactory after an average follow-up period of three years and two months. Of the 14 patients who presented with an acutely bleeding gastric ulcer, one subsequently required gastrectomy for continued bleeding; in all the others the immediate and long-term results were satisfactory. Of 21 patients with a “high” ulcer and 29 with combined gastric and duodenal ulceration one (4·8%) and three (10%) respectively suffered recurrences. We conclude that vagotomy and pyloroplasty is a satisfactory form of treatment for a high or bleeding gastric ulcer, but that for all other gastric ulcers some form of gastric resection is preferable.  相似文献   
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There are confirmable clines, by latitude, of melanin concentration in pigmentation for man as well as other mammals and birds. This has been suggested to be, in man, a result of the importance of vitamin D synthesis which can be inhibited by darker skins in higher latitudes. Experiments on mice suggest that another mechanism may be operative; greater photic stimulation of the pineal lowers the age at first estrus and may confer a reproductive advantage in this way.  相似文献   
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The following equilibrium constants (given as logK in units of m−1) were determined for the substitution of co-ordinated H2O in aquocobalamin by glycine (bound through N) 5.8, cysteine (bound through S) 6.0 or 8.3, depending on the value chosen for the pK of the thiol group, and phenolate 2.9. The spectrum of the phenolate cobalamin shows an additional intense absorption band at 468nm with a molar extinction coefficient of 1.1×104, which is assigned to a charge transfer from the phenolate to the cobalt ion. Equilibrium constants have also been determined for the equilibria between adenylcobamide cyanide and CN, HO and H+, which show that the adenine is more easily displaced by CN and HO than is 5,6-dimethylbenziminazole in vitamin B12, but can be protonated by acid while still remaining co-ordinated to the cobalt. It is shown that in the binding of corrinoids to proteins and polypeptides the formation of hydrogen bonds is far more important than co-ordination by the metal.  相似文献   
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Vinblastine inhibits the synthesis of DNA in mouse fetuses in utero, the incorporation of tritiated thymidine into the gut of the parent is, however, not altered. This selective effect, although found with other spindle inhibitors, is not due to the mitotic arresting property of the drug.  相似文献   
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