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981.
982.
Current literature has noted the various side effects of oral contraceptives. Oral surgeons have recently encountered an increased incidence of postoperative localized osteitis occurring with removal of manidibular third molars. This article documents the occurrence of this phenomenon among 105 women participating in a recent study at the Clinical Center of the National Institutes of Health. 相似文献
983.
Comments on the article by Alexander G. Wesman (see record 1968-18802-001), which proposed an organization of intelligence that views intelligence as a composite of all past learning experiences of the individual. The current author suggests that this is the same as saying that intelligence is knowledge, but states that intelligence is really the ability to acquire knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
984.
A mycobacterium, hitherto found only in wood-pigeons, was isolated from a roe-deer with generalized tuberculosis-like lesions. It is of great epidemiological interest that a mammal, under certain conditions, can attract this pathogen. 相似文献
985.
Amorphous calcium phosphate granules, containing substantial amounts of magnesium and adenosine triphosphate (ATP) have been found in the hepatopancreas of the blue crab. These stable amorphous deposits are similar in local atomic order to synthetic amorphous calcium phosphate (ACP), which, in contrast, converts to hydroxyapatite in an aqueous environment. Magnesium is known to be a stabilizing agent, and the present study shows that ATP, at levels comparable to those in the granules, also inhibits the conversion to hydroxyapatite (HA). Increasing amounts of ATP in solution, increased the time before ACP began to convert to HA, without greatly altering the rate once conversion began, an effect similar to that of Mg. Conversion was also inhibited by ADP, although less effectively, and AMP was found to be ineffective as a stabilizer. These nucleotides did not decrease the solubility of ACP, indicating that they act in solution to suppress the nucleation and/or growth of hydroxyapatite crystals. Possible stabilization mechanisms are discussed and the relationship to the action of other condensed phosphates is considered. 相似文献
986.
987.
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989.
Conflicting data in studies of the effect of natriuresis on intrarenal single nephron glomerular filtration rate (SNGFR) redistribution may arise from the interplay of hitherto largely overlooked factors. In the present work, the effect of diuresis induced by saline, glucose or mannitol, as well as the effect of anatomical nephron heterogeneity, were studied. A highly significant positive correlation was found between the logarithm of the urine flow per gram of kidney weight (log V) and the mean superficial (S) to mean juxtamedullary (JM) SNGFR ratio. The rise in S/JM SNGFR with diuresis was primarily a function of decreased JM SNGFR. Total proximal tubular length (TPL) was used as a measure of nephron size. The distribution of nephron sizes was evaluated as S/JM TPL. The effects of urine flow and anatomical heterogeneity on S/JM SNGFR were spearated by means of multiple regression analysis, which yielded the following equation: S/JM SNGFR = -0.049 + 0.179 log V + 0.818 S/JM TPL. Both slopes were highly significant (P less than 0.001). These findings indicate that S/JM SNGFR increases with urine flow, independently of sodium homeostasis, and that anatomical heterogeneity has a marked effect and must, therefore, be controlled. Conflicting data in the literature are harmonized with the present data when appropriate correction can be made for the dimensional factor. There is no evidence that SNGFR redistributions play a role in sodium homeostasis. 相似文献
990.
Globin synthesis has been studied by in vitro labelling with radioactive amino acids in 60 normal human bone-marrow samples. Under the conditions routinely used to fractionate alpha and beta chains by chromatography alpha/beta production ratios ranging from 0.5 to 1.0 were obtained, depending on the method of sample treatment. This variation was due entirely to the presence of non-haem proteins derived from white cells which chromagraphy with globin on CM-cellulose. Purification of globin on Sephadex G100 and fractionation of alpha and beta globin chains by a modified chromatographic system resulted in alpha/beta ratios of unity. The relevance of these findings to the study of marrows in which there is unbalanced globin chain production is discussed. 相似文献