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51.
Complex segregation analyses of bone mineral density in Chinese 总被引:3,自引:1,他引:2
China has the largest population in the world; approximately 7% of the total population suffers from primary osteoporosis. Osteoporosis is mainly characterized by low bone mineral density (BMD). In the present study, familial correlation and segregation analyses for spine and hip BMDs have been undertaken for the first time in a Chinese sample composed of 401 nuclear families with a total of 1,260 individuals. The results indicate a major gene of additive inheritance for hip BMD, whereas there is no evidence of a major gene influencing spine BMD. Significant familial residual effects are found for both traits, and heritability estimates (±SE) for spine and hip BMDs are 0.807(0.099) and 0.897(0.101), respectively. Sex and age differences in genotype‐specific average BMD are also observed. This study provides the first evidence quantifying the high degree of genetic determination of BMD variation in the Chinese. 相似文献
52.
R. Jiménez M. D. González M. A. Pérez J. A. García 《Ophthalmic & physiological optics》2003,23(2):97-107
The evolution of the accommodative function and development of ocular movement are evaluated in a non-clinical paediatric population (1056 subjects) aged 6-12 years, providing means for each age in the optometric tests that evaluate the accommodative amplitude, accommodative facility, accommodative response (lag), and saccadic movements. A comparison of these values between ages (anova) established three distinct trends in the behaviour of these parameters. The accommodative amplitude, measured by modified dynamic retinoscopy, and the evaluation of the saccadic movements by the development of ocular movements [developmental eye movement (DEM)] test showed continuous change with age. The values for monocular and binocular accommodative facility, measured by +/-2.00 D flippers, indicated the need to divide the population into two age groups (6-7 and 8-12 years). Finally, the means of accommodative response, measured by monocular estimation model (MEM) retinoscopy, and the direct observation of saccadic movement revealed no significant differences between ages, establishing a single mean reference value for the age group studied. 相似文献
53.
54.
对全国部分城乡家鼠鼠情监测三年结果的分析表明:城乡家鼠组成均以三大家鼠(褐家鼠、小家鼠、黄胸鼠)为主,其次为食虫目臭鼩鼱~#和黑线姬鼠。五种主要鼠种在家鼠组成中的数量比基本稳定,但三年中城乡少数鼠种间的顺位有所变化。监测结果亦表明,五种主要鼠种的地区分布是:褐家鼠、小家鼠遍布所有监测的省、市、区,同以往文献中遍布全国的说法一致;黄胸鼠分布于黄河以南;食虫目中的臭鼩鼱分布于华中区以南的广大地区。这在以往文献中均已有记载,但以往文献有关黄胸鼠和臭鼩鼱分布的其他说法,则被证实为不确切的。黑线姬鼠的分布范围已超过以往文献中关于分布于东北、华北及长江流域的说法,但以往文献中关于该鼠种遍及全国的说法是否正确,则有待进一步证实。 相似文献
55.
Yukiya Hashimoto Toshiko Koue Yuko Otsuki Masato Yasuhara Ryohei Hori Ken-ichi Inui 《Journal of pharmacokinetics and pharmacodynamics》1995,23(2):205-216
A simulation study was conducted to compare the cost and performance of various models for population analysis of the steady
state pharmacokinetic data arising from a one-compartment model with Michaelis-Menten elimination. The usual Michaelis-Menten
model (MM) and its variants provide no estimate of the volume of distribution, and generally give poor estimates of the maximal
elimination rate and the Michaelis-Menten constant. The exact solution to the Michaelis-Menten differential equation (TRUE)
requires a precise analysis method designed for estimation of population pharmacokinetic parameters (the first-order conditional
estimation method) and also considerable computational time to estimate population mean parameters accurately. The one-compartment
model with dose-dependent clearance (DDCL), in conjunction with the first-order conditional estimation or Laplacian method,
ran approximately 20-fold faster than TRUE and gave accurate population mean parameters for a drug having a long biological
half-life relative to the dosing interval. These findings suggest that the well-known MM and its variants should be used carefully
for the analysis of blood concentrations of a drug with Michaelis-Menten elimination kinetics, and that TRUE, in conjunction
with a precise analysis method, should be considered for estimating population pharmacokinetic parameters. In addition, DDCL
is a promising alternative to TRUE with respect to computation time, when the dosing interval is short relative to the biological
half-life of a drug.
This work was supported in part by the Epilepsy Research Foundation, the Nakatomi Foundation, and a Grant-in-Aid for Scientific
Research from the Ministry of Education, Science, and Culture of Japan. 相似文献
56.
Stem cells of the adult kidney: where are you from? 总被引:1,自引:0,他引:1
Takahito Ito 《Nephrology, dialysis, transplantation》2003,18(4):641-644
57.
目的:探讨地衣芽胞杆菌C01在模型小鼠体内对大肠杆菌、沙门氏菌抑制作用以及对乳杆菌等有益菌的促进作用。方法:用地衣芽胞杆菌C01灌胃肠道感染模型小鼠,采用体外活菌培养,分析粪便菌群数量的变化。结果:C01灌胃治疗组(EPEC C01)中乳杆菌的数量显著高于EPEC灌胃模型组(EPEC N)(P<0.01),肠杆菌数量下降极显著(P<0.01),而(EPEC N)组肠杆菌数显著高于正常对照组(NS)(P<0.05);肠炎沙门氏菌处理后C01灌胃治疗组(SL C01)和处理后肠炎沙门氏模型组(SL N)比较,乳杆菌、肠球菌和总厌氧菌的变化不明显,但肠杆菌数量下降极显著(P<0.01);形态病理学观察结果显示,C01芽胞杆菌灌胃治疗组肠粘膜病变明显减轻,肠粘膜及绒毛高度明显增加,绒毛轻度水肿,绒毛排列整齐、致密。结论:地衣芽胞杆菌C01在体内对肠炎沙门氏菌和致病性大肠杆菌有较强的抑制作用,能促进乳杆菌等生理性有益菌的增殖,可保护肠粘膜结构的完整性免受病原菌的侵袭。 相似文献
58.
采集450例战士血清标本,分别用国家代表株甲3/济防/15/90(H3N2)和甲3/北京/32/92(H3N2)作血清血凝抑制抗体测定,青年对甲3型抗体阳性率为60%~67%,其GMT为34~45。1994~1995年两年中在军营人群中分离到3株H3N2毒株流行株,分别应用国际、国家和地方代表株作抗原性分析,证明流行株与它们之间抗原性有明显差异。本文分离到的3株流行株均上送国家流感中心鉴定,证实为H3N2亚型毒株。 相似文献
59.
I. V. Kudryashova L. V. Nozdracheva A. A. Folomkina 《Bulletin of experimental biology and medicine》1997,123(4):348-351
It is shown that the rise of succinate dehydrogenase activity in the hippocampus depends on the number of sensory stimuli
presented before decapitation, which correlates with changes in the efficiency of glutamatergic synaptic transmission in hippocampal
sections from the same animal. Electrocutaneous stimulation potentiates the activation of succinate dehydrogenase induced
by sensory stimulation probably due to enhanced glutamate release.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 4, pp. 404–407, April, 1997 相似文献
60.