哈萨克族学生体质发育状况的10年比较分析

报道新疆阿勒泰地区1995年2589名城镇7—18岁哈萨克族(哈族)中小学生身高、体重、胸围、坐高、肩宽、骨盆宽6项体质发育指标的调查结果。男女生体质发育指标随年龄增加而增长,各项指标的年均增长值皆为男生大于女生。与1985年比较,哈族学生的身高、体重、胸围皆有不同程度增长。哈族男女生的身高突增年龄仍分别为14岁和10岁,但是其身高增长却不伴有相应比例的坐高增长,女生部分年龄组的肩宽和男女生各年龄组的骨盆宽呈现负增长,提示哈族学生的体型与10年前相比已经开始有所改变。     

Influence of Summer and Autumn Nutrition on Body Condition and Reproduction in Lactating Mule Deer

ABSTRACT Recent work suggests that availability and quality of forage in late summer and early autumn, a time when female ungulates face multiple energetic demands, is critical to reproduction in wild ungulates. Therefore, we examined direct links between nutritional quality of diets, body condition, and reproduction of lactating mule deer. Using captive mule deer, we tested the hypothesis that females consuming diets with lower digestible energy (DE; kJ/g) would have lower DE intake rates (DEI; MJ/day), have less body fat and muscle, have later estrus cycles, and have lower pregnancy and twinning rates. Deer fed lower DE diets had lower DEI during summer and autumn. In turn, deer with lower DEI, regardless of diet DE, had lower body mass, body fat, and muscle thickness. When nutritional quality of diets began to decline earlier in the summer, relationships between food quality, DEI, and body condition were stronger. Although DEI did not influence estrus date for deer that became pregnant before 21 December, deer with lower DEI had a lower probability of becoming pregnant and had a lower probability of producing twins. Measures of body condition in October (i.e., body mass, body fat, and muscle depth) predicted pregnancy and twinning rates in mule deer. Serum concentration of hormones leptin and Insulin Growth Factor 1 were not good predictors of body condition or reproduction. These findings suggest that managers concerned with productivity of mule deer populations should consider focusing on assessing and improving quality of forage available in summer and autumn.     

生长激素-海藻酸钠-壳聚糖微胶囊促进骨折愈合的组织学研究

目的:观察生长激素-海藻酸钠-壳聚糖微胶囊促进兔挠骨骨折愈合的作用。方法:实验将新西兰兔80只,在制备新西兰兔右桡骨中段3mm骨缺损模型的基础上,随机分成四组:口服生长激素-海藻酸钠-壳聚糖微胶囊组、皮下注射生长激素组、口服空微胶囊组和生理盐水对照组。实验组口服生长激素-海藻酸钠-壳聚糖微胶囊和皮下注射生长激素,对照组口服空微胶囊。并于术后9、17、30、42d定期HE染色和地衣红染色观察各组的骨折愈合情况。结果:本实验HE染色结果表明,由于在骨缺损部位成纤维细胞产生的大量胶原纤维为基质,形成透明软骨及成骨细胞,骨小梁生长的基础,连接骨痂形成和骨髓腔贯通。而观察到生长激素微胶囊组各期提前生长及改建提前的形态。地衣红染色图像结果分析及直方图的分析表明:生长激素微胶囊组胶原纤维产生促进骨小梁提前形成,进而骨折处骨性骨痂的提前愈合和髓腔的提前贯通。结论:生长激素-海藻酸钠-壳聚糖微胶囊口服能促进骨折修复愈合。     

一株产阿魏酸酯酶青霉菌株的筛选、鉴定及生长特征

从腐烂的木质纤维中筛选了一株产阿魏酸酯酶的菌株HDFE1,根据其形态特征、rDNAITS1-5.8S-ITS2序列及系统发育分析,鉴定菌株HDFE1为青霉属的橘青霉(Penicillium citrinum Thom)。菌株HDFE1最适生长温度为30°C,最适生长pH为6.0。该菌株在30°C、pH6.0、200r/min培养60h时,阿魏酸酯酶酶活力为最高,达20.75U/L。     

中外水质基准发展趋势和存在的问题

水质基准,是制定水质标准限值的重要依据,是科学的水质管理体系的重要组成部分。我国水体污染形势严峻,区域环境差异明显,亟需建立适合我国水环境特征的水质基准作为水质控制和管理的理论依据。本文就中外水质基准的研究情况进行了探讨,主要包括以下几个方面:1)水质基准的概念及含义;2)欧美国家水质基准的研究历史、现状、发展趋势及存在的关键问题;3)我国水质基准体系的研究重点和发展趋势:包括区域水环境特征调查、人体流行病学调查和生物毒理学研究、水质基准理论与方法学的研究。     

Appetite and growth compensation in the European minnow,Phoxinus phoxinus (Cyprinidae), following short periods of food restriction

Synopsis Changes in the daily appetite and weekly growth rates of individual adult minnows,Phoxinus phoxinus, on ad libitum rations were recorded before and after they had experienced 4 or 16 days of food restriction. Feeding levels during the restriction periods were either starvation or a maintenance ration. The latter was estimated from a previously determined regression model. Water temperature was 15°C and the photoperiod 9L15D in all experiments. The mean weight of fish used ranged from 1.06 to 2.15 g. The 4 day restriction had no detectable effects on appetite or growth. After the 16 day restriction, the minnows showed hyperphagia and had increased specific growth rates and growth efficiencies compared with control fish. The compensatory increases in appetite and growth were not sustained and within three weeks had declined to levels not significantly different from those of the control fish. At the end of the experiments, there were no significant differences between the mean weights or cumulative food consumption of the restricted and control groups. The results suggest that adult minnows regulate their appetite and growth rate in relation to their previous nutritional history.     

In vivo activated caspase-3 cleaves PARP-1 in rat liver after administration of the hepatocarcinogen N-nitrosomorpholine (NNM) generating the 85 kDa fragment

We reported previously that treatment of rats with the hepatocarcinogen N-nitrosomorpholine (NNM) caused severe hepatotoxicity associated with apoptosis of hepatocytes beginning 12 h after administration of NNM. We observed that poly(ADP-ribose) polymerase 1 (PARP-1), one of the major nuclear targets for caspases, was proteolytically degraded generating primarily 64 and 54 kDa fragments. Interestingly, at 20, 30, and 40 h post-treatment a 85 kDa cleavage product of PARP-1 resembling that generated by caspase-3 appeared additionally in hepatocytes. More detailed analysis performed in the present study revealed that the 85 kDa fragment of PARP-1 was generated in the liver in 10 of 17 (60%) animals examined between 20 and 40 h after NNM administration. The caspase-3 generated 85 kDa fragment was detected solely in hepatocytes undergoing apoptosis as evidenced by immunostaining performed with the antibody recognizing exclusively PARP-1 cleaved at position 214/215. The appearance of the 85 kDa fragment of PARP-1 in the liver nuclei coincided temporally with an significant increase of caspase-3 activity in hepatocytes. In contrast, in testis samples obtained from the same animals, no changes characteristic for apoptosis such as induction of caspases activity or degradation of nuclear PARP-1 could be detected. Our results evidence unequivocally that PARP-1 in liver is not resistant to caspases and can be processed in vivo by activated caspase-3 producing the p85 kDa fragment. Moreover, the caspase-3 induced PARP-1 fragmentation coinciding with the increase of caspase-3 activity was detected solely in the target organ and exclusively in hepatocytes undergoing apoptosis. Considering the fact that the caspase-3 mediated PARP-1 cleavage occurred only in 60% of animals tested between 20 and 40 h, it becomes obvious that the cellular response in vivo to the same trigger(s) strongly varies and may depend on a variety of intrinsic factors. It remains to elucidate which additional factors may be involved in the modulation of cellular response to the strong insults thereby activating different pathways and generating distinct outcomes.     

Habitat associations with topography and canopy structure of tree species in a tropical montane forest on Mount Kinabalu,Borneo

Habitat associations with topography and canopy structure of 42 abundant tree species were studied in a 2.74-ha plot of tropical montane forest on Mount Kinabalu, Borneo. Many of these species belong to the same higher taxa including eight families and four genera. Analysis of intraspecific spatial distributions for stems ≥ 10 cm diameter revealed that 28 species (including all six species of Fagaceae) showed aggregated distributions at the 100-m² and/or 400-m² scales, and that 20 species showed habitat associations with topography by torus-translation tests; 17 species showed both characteristics. Species' associations with the local canopy structure were characterized by crown position index (CPI), which was defined relative to neighbour trees. The CPI differed greatly among individual stems at 10–40 cm diameter, and 19 species showed significantly different frequencies of crowns exposed vertically versus those shaded beneath the canopy. Mean growth rates at 10–40 cm diameter and size distributions of species were not related to topographic associations, but were explained by the associations with canopy structure; species with more exposed crowns grew faster and had less positively skewed distributions. Diversity in habitat associations was manifest between two genera (Syzygium and Tristaniopsis) in the family Myrtaceae and among species in these genera, but was less evident in other families and two genera (Garcinia and Lithocarpus). This revised version was published online in June 2006 with corrections to the Cover Date.     

Local Perfusion of Nicotine Differentially Modulates Somatodendritic Dopamine Release in the Rat Ventral Tegmental Area After Nicotine Preexposure

We examined the effects of nicotine perfusion into the ventral tegmental area (VTA) on extracellular dopamine (DA) levels in rats using in vivo microdialysis. Local perfusion with nicotine for 80 min (10–100 M) modestly increased (105–131% of basal) the extracellular DA levels in the VTA of rats that had been pretreated with saline for 5 days. In animals that had been pretreated with nicotine for 5 days (0.3 mg/kg, s.c.), perfusion with nicotine for 80 min (10–100 M) dose-dependently increased the extracellular DA levels in the VTA of rats and did so to a greater extent than in saline-pretreated animals (125–171% of basal). Co-perfusion through the dialysis probe with 100 M mecamylamine, a nonselective nicotinic acetylcholine receptor (nAChR) antagonist, or 100 M dihydro--erythroidine, a high affinity and competitive nAChR antagonist, attenuated the enhancement of extracellular DA levels produced by 100 M nicotine alone. These results suggest that local nicotine challenge potentiated the somatodendritic DA release after nicotine preexposure by stimulation of high-affinity nAChRs in the VTA.