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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
981.
K C Ho U Roessmann L Hause G Monroe 《Journal of neuropathology and experimental neurology》1986,45(2):179-188
This study compares the weight of the human brain to gestational age and body dimensions. A new formula for calculating the rate of growth is proposed. It consists of a second order polynomial function: Y = A0 + A1X + A2X2, in which Y is brain weight, body weight, height, or body surface area; X is gestational age in weeks and A0, A1, and A2 are statistically estimated coefficients. In utero, the growth rate is most rapid for body weight, followed in decreasing order by brain weight, body surface area, and height. Brain growth is the same for both sexes in black and white races; it accelerates between the 20th and 45th weeks of gestation. The size of the newborn infant brain is directly related to gestational age and body size and is not determined by sex or race. 相似文献
982.
983.
D-xylose disposition was examined in 24 healthy men between 32 and 85 years of age. Xylose was administered as a 5 gm iv infusion and as a 25 gm po solution. Serum xylose concentrations and urinary excretion of intact xylose were determined. There were statistically significant inverse relationships with age for each of the following parameters after intravenous infusion: elimination rate constant (r2 = 0.71); systemic clearance (r2 = 0.66); renal clearance (r2 = 0.66); and nonrenal clearance (r2 = 0.35). Similar inverse relationships were found after oral dosing for the elimination rate constant (r2 = 0.69) and renal clearance (r2 = 0.54). There was no significant age relationship for the apparent volume of distribution or the steady-state volume of distribution. The percentage of the oral and intravenous dose recovered in urine up to 5 hours after dosing was significantly and inversely correlated with age. The implications of the latter finding are discussed with regard to the interpretation of the xylose tolerance test used to assess gastrointestinal absorptive capacity. 相似文献
984.
Adenocarcinoma of the lower esophagus. A disease primarily of white men with Barrett's esophagus 总被引:3,自引:0,他引:3
E L Rogers S F Goldkind O A Iseri M Bustin L Goldkind S R Hamilton R L Smith 《Journal of clinical gastroenterology》1986,8(6):613-618
Sex and racial predilection, social history, and histology were analyzed in a biopsy-proven adenocarcinoma of the lower esophagus/esophagogastric junction collected over a 5-year period in two teaching institutions with different patient populations. Adenocarcinoma occurred in 11% of patients with biopsy-proven esophageal cancer. The disease occurred only in males at one center, and in a 7:1 ratio of males to females at the other center. Clear racial predilection was seen, since 12 of 13 patients with adenocarcinoma of the esophagus were white, whereas less than 20% of patients with squamous carcinoma of the esophagus were white. The finding of Barrett's epithelium in eight of the 13 cases strongly supports the theory that in white males, Barrett's epithelium is a precursor lesion of adenocarcinoma of the esophagus/esophagogastric junction. 相似文献
985.
986.
R L Hiatt 《Annals of ophthalmology》1986,18(11):332-336
A transfer procedure is very useful in the treatment of strabismus. The most common use of this procedure is to augment an already planned resection or recession procedure so that it can be performed monocularly to reduce an accompanying hypertropia or hypotropia or to collapse the A or V pattern when horizontal surgery is being performed for estropia or exotropia. In transfer procedures, the resultant change of deviation and cosmetic improvement is good or excellent in almost all cases. Some special transfer procedures, such as the Harada-Ito or the Jensen operation, can have dramatic effects on both comfort and change of symptoms for the patient. 相似文献
987.
988.
989.
990.
Joke van Welzen Alex M. van Herk Anton L. German 《Macromolecular chemistry and physics.》1987,188(8):1923-1932
The structural behaviour of cobalt(II)phthalocyanine-tetrasodium sulfonate (CoPc(NaSO3)4) ( 1 ), a catalyst used in thiol oxidation, was investigated in the presence of ionenes (poly-quaternary ammonium salts), ( 2 ) using visible light spectroscopy. It was observed that ionenes, which have been shown to promote the catalytic activity, strongly enhance the aggregation of the cobalt complex. No cobalt site isolation occurred up to N+/Co = 105. Furthermore, a stoichiometric CoPc(NaSO3)4/ionene complex appeared to be formed with an N+/Co-ratio of 4:1. This ratio was found to hold for ionenes with M?n varying from 6 100 to 22 000 and charge densities from 0,8 to 1,5. As the charge density was increased, the observed CoPc(NaSO3)4 spectrum was more affected. Experiments with oxygen in alkaline solution revealed that the complex was resistant toward oxygen adduct formation in the presence of ionenes. This phenomenon is discussed in relation to the catalytic activity of the system. 相似文献