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81.
广东瑶族青少年学生体表面积研究 总被引:4,自引:0,他引:4
研究瑶族青少年身高、体重及体表面积的生长发育状况, 为建立瑶族中小学生健康指标评价体系提供依据。采用Stevenson公式和胡咏梅公式计算每位学生的体表面积, 并求得7—18岁12个年龄组的男女学生的体表面积均数。结果显示: 瑶族青少年学生的身高、体重及体表面积随年龄增长而增长, 且其增长速度男女生均可分为匀速增长期、快速增长期、缓慢增长期3个不同时期; 男女生身高、体重及体表面积发育曲线均出现双交叉现象。两法统计的瑶族青少年的体表面积均随年龄增长而增长。胡咏梅法计算的体表面积大于Stevenson法(P<0.01)。 相似文献
82.
Some relevant traits of a wild (L) and a laboratory (C) strain of Hylemya antiqua (Meigen ), determining differences in their pupation ability under experimental conditions have been investigated in relation to genetic control. The wild strain showed an intrinsic higher pupation ability than the laboratory strain. The minimum feeding period was 0.6 days longer for the C strain. The minimum larval dry weight was different for the two strains. With a normal feeding period C larvae pupated on average 1.63 days later than L larvae. By the shortening of the larval feeding period an acceleration of the larval development of both strains was observed: the acceleration of development was more marked for the wild strain. This result has been contrasted with published works on Drosphila. The consequences of these differences as far as the competitive ability of each strain is concerned, have been discussed in relation to genetic control. 相似文献
83.
Masakazu Shiga 《Population Ecology》1977,18(2):284-301
Stabilizing mechanism in population of Malacosoma neustria testacea was investigated in a central part of Japan based on eight year survey. Population fluctuation in each developmental stage in the experimental field was rather small, i.e., 5.9 times in egg and 85.0 times in female adult. Pupal weight negatively correlated with the densities of 5th instar larvae and prepupae (cocoons) and correlation coefficient was highly significant in females. Population density was stabilized by density-dependent dispersal of female moths in preovipositional period. Comparison between fecundity of emerged moths and that of actually oviposited ones in the experimental field suggested that density-dependent dispersal took place as the result of density-dependent size variation, i.e., small-sized female months have higher flying ability. This hypothesis was supported by the experiment in which flying ability of newly emerged female moth was measured. Similar stabilizing mechanism is expected to occur in semelparous or pro-ovigenic insects. 相似文献
84.
Ryo Tanaka 《Population Ecology》1962,4(1):8-16
Summary The vole,Eothenomys smithi, in highlands of Shikoku was studied to disclose ups and downs of adrenal activities under the influence of the breeding
level in natural populations. It has proved that the vole's adrenal in both sexes may be much more strongly by rise and fall
of the fertility as well as by shift of the age structure in populations than the rat's. Therefore, as for perhaps all kinds
of small mammals, we consider necessary to follow a pertinent procedure to avoid thoroughly these sources of error in studies
to draw any conclusion for or against theChristian's theory. The present data analysed by such a method failed to afford any confirmative proofs; the fact that the pregnancy
rate was increased in parallell to the density is against his view. However, never the whole content of the theory has been
invalidated by these results. 相似文献
85.
Hilary C. Rees Voichita Ianas Patricia McCracken Shannon Smith Anca Georgescu Tirdad Zangeneh Jane Mohler Stephen A. Klotz 《Journal of visualized experiments : JoVE》2013,(77)
A simple, validated protocol consisting of a battery of tests is available to identify elderly patients with frailty syndrome. This syndrome of decreased reserve and resistance to stressors increases in incidence with increasing age. In the elderly, frailty may pursue a step-wise loss of function from non-frail to pre-frail to frail. We studied frailty in HIV-infected patients and found that ~20% are frail using the Fried phenotype using stringent criteria developed for the elderly1,2. In HIV infection the syndrome occurs at a younger age.HIV patients were checked for 1) unintentional weight loss; 2) slowness as determined by walking speed; 3) weakness as measured by a grip dynamometer; 4) exhaustion by responses to a depression scale; and 5) low physical activity was determined by assessing kilocalories expended in a week''s time. Pre-frailty was present with any two of five criteria and frailty was present if any three of the five criteria were abnormal.The tests take approximately 10-15 min to complete and they can be performed by medical assistants during routine clinic visits. Test results are scored by referring to standard tables. Understanding which of the five components contribute to frailty in an individual patient can allow the clinician to address relevant underlying problems, many of which are not evident in routine HIV clinic visits. 相似文献
86.
多形拟杆菌对糖尿病模型小鼠的影响 总被引:2,自引:0,他引:2
目的研究多形拟杆菌(BT)干预糖尿病模型小鼠后对血糖、体重和C肽的影响。方法 (1)用四氧嘧啶(200 mg/kg腹腔注射)制备糖尿病模型小鼠,并分成四组:空白组(n=10)、空白给菌组(n=10)、四氧嘧啶糖尿病模型组(n=11)和模型给菌组(n=11),15 d。(2)BHI血琼脂培养基培养ATCC 29148标准菌株,比浊法测定混悬菌液数量。(3)用多形拟杆菌菌液干预空白给菌组和模型给菌组小鼠,观察15 d中四组小鼠的体重、空腹血糖水平的变化;实时荧光定量PCR测定小鼠肠道内多形拟杆菌的数量;运用酶联免疫法(ELISA)测定血清中C肽的水平。结果 (1)给予菌悬液后,空白给菌组与空白组相比,BT在第3天就可以定植并维持到第15天。与模型组相比,模型给菌组在第15天时可以定植;(2)线性回归相关性分析显示,肠道内多形拟杆菌与体重呈负性相关(r=-0.70,P0.05);与空腹血糖(FPG)呈正性相关(r=0.71,P0.05);与C肽呈负性相关(r=-0.62,P0.05);与胰岛素抵抗指数(HOMA-IR)呈正性相关(r=0.55,P0.05);与胰岛素分泌指数(HOMA-IS)呈负性相关(r=-0.43,P0.05)。结论 (1)外源性灌胃给予多形拟杆菌可以在肠道内定植。(2)肠道内多形拟杆菌的数量变化与糖尿病有相关性。 相似文献
87.
We analyze self-reported anthropometric data pertaining to 2140 adults who emigrated to the United States, mainly from southern Italy, between 1908-1928 and 1960-1970. The mean height of immigrant men was 165.5 cm: they were taller than contemporary southern Italian men by 0.5-7.3 cm in different periods. The mean height of the Italian immigrant women born before 1952 was 157.6 cm, less than the national average. At the end of the 1990s, national women average height was 162 cm, 159.5 cm for southern women. There were age-related increases of weight and BMI: overweight was more prevalent in the 40-49 years age category. In the male sample, the mean values of BMI were within the overweight range in all age classes. The prevalence of obesity was higher in the male sample than among US men, whereas it was virtually identical in the women's sample and much higher than the values reported for several European countries for the period 1970-1980. 相似文献
88.
Idris Adewale Ahmed Maryam Abimbola Mikail Mohammad Rais Mustafa Muhammad Ibrahim Rozana Othman 《Saudi Journal of Biological Sciences》2019,26(7):1519-1524
Non-alcoholic fatty liver disease (NAFLD) is a multi-factorial disease and the most common of chronic liver diseases worldwide. The four clinical-pathological entities which are usually followed by NAFLD course include non-alcoholic steatosis, non-alcoholic steatohepatitis, advanced fibrosis/cirrhosis, and hepatocellular carcinoma. The cornerstones of NAFLD management and treatment, however, are healthy lifestyles such as dietary modifications, regular physical activity, and gradual weight loss. At present, no drugs or pharmacological agents have been approved for long-term treatment of NAFLD. Therefore, lifestyle modification is considered the main clinical recommendation and an initial step for the management of NAFLD. 相似文献
89.
Ziebell A Gracom K Katahira R Chen F Pu Y Ragauskas A Dixon RA Davis M 《The Journal of biological chemistry》2010,285(50):38961-38968
The lignin content of biomass can impact the ease and cost of biomass processing. Lignin reduction through breeding and genetic modification therefore has potential to reduce costs in biomass-processing industries (e.g. pulp and paper, forage, and lignocellulosic ethanol). We investigated compositional changes in two low-lignin alfalfa (Medicago sativa) lines with antisense down-regulation of p-coumarate 3-hydroxylase (C3H) or hydroxycinnamoyl-CoA:shikimate hydroxycinnamoyltransferase (HCT). We investigated whether the difference in reactivity during lignification of 4-coumaryl alcohol (H) monomers versus the naturally dominant sinapyl alcohol and coniferyl alcohol lignin monomers alters the lignin structure. Sequential base extraction readily reduced the H monomer content of the transgenic lines, leaving a residual lignin greatly enriched in H subunits; the extraction profile highlighted the difference between the control and transgenic lines. Gel permeation chromatography of isolated ball-milled lignin indicated significant changes in the weight average molecular weight distribution of the control versus transgenic lines (CTR1a, 6000; C3H4a, 5500; C3H9a, 4000; and HCT30a, 4000). 相似文献
90.
Man Z Kondo Y Koga H Umino H Nakayama K Shin HW 《The Journal of biological chemistry》2011,286(13):11569-11578
Arfaptins (arfaptin-1 and arfaptin-2/POR1) were originally identified as binding partners of the Arf small GTPases. Both proteins contain a BAR (Bin/Amphiphysin/Rvs) domain, which participates in membrane deformation. Here we show that arfaptins associate with trans-Golgi membranes. Unexpectedly, Arl1 (Arf-like 1), but not Arfs, determines the trans-Golgi association of arfaptins. We also demonstrate that arfaptins interact with Arl1 through their BAR domain-containing region and compete for Arl1 binding with golgin-97 and golgin-245/p230, both of which also bind to Arl1 through their GRIP (golgin-97/RanBP2/Imh1p/p230) domains. However, arfaptins and these golgins show only limited colocalization at the trans-Golgi. Time-lapse imaging of cells overexpressing fluorescent protein-tagged arfaptins and golgin-97 reveals that arfaptins, but not golgin-97, are included in vesicular and tubular structures emanating from the Golgi region. These observations indicate that arfaptins are recruited onto trans-Golgi membranes by interacting with Arl1, and capable of inducing membrane deformation via their BAR domains. 相似文献