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1.
This paper describes changes in the uterine size during the normal course of pregnancy in cynomolgus monkeys. Twenty-four females which had conceived by 3-day individual mating with a male were laparotomized 4,5,6,7,8,9,10,15 and 20 weeks after conception. The width, thickness and length of uterus were measured by a pair of callipers. Them, the uterine volume was estimated by the formula, V = 4/3 piab2 (a, b: uterine length x 1/2, uterine width x 1/2). The increase in the uterine width (y) during pregnancy could be expressed as a linear equation: y = 0.35x + 1.48 (x: weeks after conception). The thickness of pregnant uteri could be represented by a a linear equation: y = 0.36x + 1.40. From the 4th to the 20th week of pregnancy, the uterine length increased along a straight line expressed as a linear equation: y = 0.58x + 1.14. Except for nonpregnant uteri, the change in the uterine volume after pregnancy could be expressed as a linear logarithmic equation: log y = 2.319 log x -0.315. These 24 pregnant monkeys had followed the normal course of gestation until the time of laparotomy without any abnormality in their fetuses of their placentas, indicating that the values obtained throughout this study are of practical use for taking care of pregnant cynomolgus monkeys.  相似文献   

2.
半湿润常绿阔叶林次生演替阶段植物多样性和群落结构特征   总被引:10,自引:1,他引:10  
以飒马场不同次生演潜阶段的半湿润常绿阔叶林为对象,测定物种丰富度、群落数量特征指标,分析植物多样性与群落结构特征之间的关系.结果表明,随着植物群落演替,物种丰富度不断增加,物种丰富度最高演替阶段的乔木层物种达到24个;植物多样性与植物个体密度间呈正相关关系;乔木层植物个体平均高与植物多样性间呈负相关关系;群落郁闭度和胸高断面积与植物多样性之间则呈对数函数关系.植物多样性与优势种个体密度和群落地上部分现存量间未呈现一致性规律.植物种-个体数间呈幂函数关系.随着植物多样性增加,种间竞争加剧.每个植物种为了维持临界最低种群,可能采取最大种群策略,导致群落植物个体数增加,密度增大,从而改变了群落结构特征.  相似文献   

3.
大型溞生长、生殖和种群增长的研究   总被引:10,自引:3,他引:7  
年龄6±6小时的纯系大型溞培养在25±1℃静置换水条件下,饲以斜生栅藻,其平均寿命为68.40±9.82天。龄期(x)和年龄(t,天)之间呈曲线迴归关系:t=-2.245+1.510x+0.035x2(r=0.99,p3.86-0.131t)(式中Y为累计生殖量个数,t为天数)。    相似文献   

4.
张文辉  祖元刚 《植物研究》1998,18(1):118-118
在不同生境条件下的固定样地内,观察分析了裂叶沙参种群的地上部分在一个生长季的生长过程和物侯特点。生长于灌木群落下,裂叶沙参地上部分生物量生长(y,g)与时间(x、d)的关系可以用公式:y=0.2872-0.0187x+0.0009x^2表示;地上各器官茎、叶、花枝、花芽、花和果的生物量(y,克)与生长时间(x,天)的关系可以用公式:y=b0+b1x+b2x^2表示。从4月10日到8月15日的速生期  相似文献   

5.
BACKGROUND: Harvesting of hemopoietic stem cells (HSC) from G-CSF-primed BM for autologous transplantation is an alternative to collection of unprimed BM or G-CSF-primed peripheral blood (PB). However, the optimum number of days of G-CSF administration for this purpose is unknown. We set out to determine whether cell yields could be optimized by varying the number of days of G-CSF administration prior to BM stem cell harvesting. METHODS: We conducted a randomized controlled single-center trial of 6 days (the standard) vs. 4 days of G-CSF administration and compared yields of total nucleated cells (TNC), CD34(+) HSC and CFU-GM cells per kilogram patient body weight. Statistical analysis was by Student's t-test. RESULTS: Twenty-four patients were enrolled; 13 received 6 days and 11 received 4 days of G-CSF administration. Analysis of the first harvest aspirate showed higher proportions of CD34(+) HSC (P=0.02) and CFU-GM (P=0.03) in the 4-day group. For the 6-day and 4-day groups, respectively, the median yield of TNC/kg was 6.5 x 10(8) and 5.4 x 10(8) (P=0.28), of CD34(+) cells/kg 0.56 x 10(6) and 0.98 x 10(6) (P=0.04) and of CFU-GM cells/kg 1.66 x 10(5) and 1.55 x 10(5) (P=0.75). DISCUSSION: These results suggest that by 6 days the HSC-stimulating effect of G-CSF has passed its peak and that 4 days should be adopted as the standard for G-CSF priming prior to BM stem cell harvesting for autologous transplantation.  相似文献   

6.
Continuous culture of RPMI 8226 human hematopoietic cells was performed. The viable cell number and glucose, lactate and ammonium concentrations became constant within 3–4 days at a constant dilution rate. The viable cell number decreased at low and high dilution rates. The growth and product yields slightly depended on the dilution rate, except for product yield for lactate based on cell number. Growth characteristics of these cells at various dilution rates could be expressed by equations considering the maintenance energy in growth yield. Maximum specific growth rate could be evaluated from the wash-out profile and the known inhibition constants.  相似文献   

7.
棉花体细胞再生过程中代谢物质变化规律的初探   总被引:4,自引:0,他引:4  
本文对诱导起始到胚分化整个过程中的愈伤组织的代谢物质进行生理生化分析,得到如下结果:1、可溶性糖和淀粉含量随着培养天数增加逐渐下降,下降趋势分别符合方程y=1.0572-0.0059x,y=2.342-0.0114x;2、蛋白质和核酸含量随着培养天数增加逐渐上升,上升趋势分别符合方程:y=0.261+0.0054x,y=0.329+0.0023x。  相似文献   

8.
Expression and implication of carbohydrate antigens in squamous cell carcinomas (SCCs) in oral cavity was examined. In the cell lines, type 2H and Lewis y antigens were markedly expressed. In the tissues from SCC patients and benign disorders, type 2H was highly expressed in hyperplasia (96.4 %), displasia (92.9 %) and SCC (100 %). Lewis y was, in turn, expressed mainly in cancer tissues (91.3 %), suggesting that Lewis y is a cancer-associated antigen. Normal oral mucosa showed no expression of these blood group antigens. Surprisingly, Lewis y antigen disappeared in the invasion sites where Ki-67 was definitely stained. Over-expression of Lewis y with manipulation of a fucosyltransferase cDNA resulted in suppression of cell growth and invasion, and knockdown of Lewis y also brought about increased cell growth and invasion. In either situations, no changes in the expression of sialyl-Lewis x could be found. Lowered tumor growth and invasion into surrounding tissues were also shown in Lewis y-positive SCC grafts in nu/nu mice. All these results together with alternative staining between Lewis y and Ki-67 in cancer tissues and FUT1 transfectants suggested that loss of Lewis y is a crucial event for the late stage of SCCs.  相似文献   

9.
厦门市交通主干道绿化带结构及其减噪效果研究   总被引:3,自引:1,他引:3  
通过对厦门市主干道绿化带种类结构调查以及噪声测定等,分析了厦门市主干道绿化带结构及其减噪效果。结果表明,厦门市主干道绿化带可分为4种结构:单一乔木型、乔木+疏灌木/绿篱型、乔木+密灌木型以及乔木+小乔木+灌木/绿篱型,带宽多在4~10 m。厦门市主干道绿化带总体减噪能力为0.93~12.96 dB,绿化带对交通噪声超标治理率达70%。绿化带减噪能力y(dB)与带宽x(m)呈显著的线性关系:y=1.2251x+0.2416(R2=0.8603);绿化带的附加衰减与总衰减亦呈显著正相关:y=0.4535x+0.2698 (R2=0.9242),噪声的附加衰减主要受绿化带结构的影响,上述四种结构对噪声附加衰减平均值分别达0.93、2.25、4.43和6.72 dB。绿化带的宽度和结构均是影响其减噪效果的关键因素。  相似文献   

10.
升马唐种群生态及其田间密度调控指标的研究   总被引:11,自引:3,他引:8       下载免费PDF全文
 研究表明,马唐的生育期为62—111天,需>0℃积温1380—2716。其生殖生长阶段对季节的温度要求严,营养生长阶段宽,生育期长短主要靠营养生长期的长短来调节。马唐种子休眠期一般为150天,休眠期长短和解除休眠速率与种子贮藏条件关系密切,以恒温贮藏最快。种子发芽起点温度为15℃,60%种子发芽的有效积温平均为555.13℃。马唐种子发芽对光照要求不敏感。在农田7cm土层内的种子均能出苗,但以1—4cm层最佳。马唐的再生能力强,试验表明,凡是带有须根和幼芽的任何断节都能发生新的植株。通径分析结果表明,马唐是我国北方夏播粮田的主要杂草。马唐群体水平(x,株/m2)与夏玉米籽粒减产率(y,%)间呈以下关系模式:(1)y=0.1532x1-5574(x≤20株/m2) (2)y=-18.400+11.315lnx(x>20株/m2)与夏玉米共同生长日数对作物籽粒减产率呈以下关系模式:y=54.5956/1+89.7962e-0.1184x根据推算,在石家庄地区夏播玉米田,马唐的允许存在密度即生态经济阈值为5.8株/m2。  相似文献   

11.
珍稀濒危保护植物蒙古扁桃的生长特性研究   总被引:1,自引:0,他引:1  
通过连续9 a定株观测方法,研究了蒙古扁桃物候期对应气候因子指标、年株高变化、地径生长、冠幅变化及根系变化规律,结果表明:物候期与气温、地表温度、地温(15 cm)、空气湿度和水汽压等因子关系密切,而与蒸腾量和日照时数关系较疏;年株高变化符合直线方程:y=18.91 8x-0.780 6(R2=0.991 5);年地径变化符合直线方程:y=0.275 6x 0.348 6(R2=0.999 2);年冠幅变化符合指数方程:y=50.371e0.2527x(R2=0.989 9);根系纵向和横向生长趋势分别符合指数函数方程:y=12.914e0.7358x(R2=0.971 5)和y=17.126e0.6918x(R2=0.965 4),但纵向生长落后于横向生长,即侧根生长优于主根。  相似文献   

12.
Morphometrical analysis of microtubules (MT) and coated vesicles (CV) was done on electron micrographs of the murine mammary gland sections at the final stages of functional maturation of secretory cells (SC), as well as at different stages of the cell secretory cycle (CSC). The results obtained allow to make the following conclusions: 1) dynamics of changes in the MT count in different subplasmalemmal cell compartments is similar, being directly associated with heterochronical character of CSC processes; 2) the maximum MT count in SC was seen during formation of the secretion product, this increase occurring at the expense of short MT, which are disassembled before and during exocytosis of secretory vesicle (SV) contents; 3) changes in the number of MT and CV are of similar character, which was revealed by morphometrical analysis of SC in the course of maturation. The number of MT and CV in SC increased rapidly and significantly on the 1st and 2nd days after parturition, compared to that observed 1-2 days before parturition. However, the number of MT and CV decreased by the 10th day of lactation, when the mammary secretory activity reached its maximum. Both correlation and regression statistical analyses made during the CSC development point to a linear relation between MT (x) and CV (y) numbers. Regression of y on x is: y = -0.89 + 12.43x. A hypothesis about the possibility of MT participation in CV and SV transport and in the formation of a barrier on the path leading to exocytosis of SV contents is suggested.  相似文献   

13.
The purpose of this study was to quantify the decrease in the load lifted from 1 to 5, 10, and 20 repetitions to failure for the flat barbell bench press (chest press; CP) and plate-loaded leg press (LP). Furthermore, we developed prediction equations for 1 repetition maximum (RM) strength from the multiple RM tests, including anthropometric data, gender, age, and resistance training volume. Seventy subjects (34 men, 36 women), 18-69 years of age, completed 1, 5, 10, and 20RM testing for each of the CPs and LPs. Regression analyses of mean data revealed a nonlinear decrease in load with increasing repetition number (CP: linear S(y.x) = 2.6 kg, nonlinear S(y.x) = 0.2 kg; LP: linear S(y.x) = 11.0 kg, nonlinear S(y.x) = 2.6 kg, respectively). Multiple regression analyses revealed that the 5RM data produced the greatest prediction accuracy, with R(2) data for 5, 10, and 20RM conditions being LP: 0.974, 0.933, 0.915; CP: 0.993, 0.976, and 0.955, respectively. The regression prediction equations for 1RM strength from 5RM data were LP: 1RM = 1.0970 x (5RM weight [kg]) + 14.2546, S(y.x) = 16.16 kg, R(2) = 0.974; CP: 1RM = 1.1307 x (5RM weight) + 0.6999, S(y.x) = 2.98 kg, R(2) = 0.993. Dynamic muscular strength (1RM) can be accurately estimated from multiple repetition testing. Data reveal that no more than 10 repetitions should be used in linear equations to estimate 1RM for the LP and CP actions.  相似文献   

14.
Oxygen consumption (ml X kg-0.75/min) in relation to ambient temperature (Ta) in the raccoon dog whelps at the ages of 7-9 weeks and 17-19 weeks is described by equations y = 32.9-0.69x and y = 26.2-0.49x, respectively. The corresponding equations to adults in summer and winter pelages are y = 19.6-0.46x and y = 14.5-0.32x, respectively. The cooling constant (min-1) of deceased raccoon dogs decreased exponentially with increasing body mass, while M-0.75 specific heat transfer coefficient (W X kg-0.75/degrees C) regressed linearly on body mass, y = 0.124-0.00066x. Cooling rate of deceased animals were more dependent on body mass than on pelage quality.  相似文献   

15.
以‘储良’和‘石硖’2个龙眼品种的成熟叶为材料,对叶片的周长、长、宽、长/宽、宽×宽、长×长、长×宽等指标与叶面积的相关性进行分析,建立9种模拟回归方程。结果表明,‘储良’和‘石硖’的叶面积均可用叶片的周长、长、宽、长/宽、宽×宽、长×长、长×宽等指标进行估算,基于叶长×叶宽建立的9种叶面积回归方程R2均最高,拟合效果最好,且相关性最大,因此叶片长×宽可作为龙眼叶面积估测的首选指标。基于叶长×宽建立的9个回归方程中,一元线性方程、二次方程、三次方程、幂函数能较好拟合,其中以幂函数估算的精度最高,较适合用来估测龙眼的叶面积。‘储良’和‘石硖’叶面积对应的较为精准的叶面积幂函数方程分别为:y=0.751x1.006和y=0.986x0.973。最适合两个龙眼品种的总叶面积幂函数方程为y=0.869x0.988。  相似文献   

16.
The hyperthermophilic archaeon Pyrococcus furiosus was cultivated in batch and continuous fermentations on different carbon substrates. The cultivation of P furiosus on soluble starch as the only carbon source resulted in cell densities three times higher than in cultivations on maltose, 1.06 x 10(10) cells/ml compared to 3.4 x 10(9) cells/ml. The yield coefficient, Y(x/y) = 0.12 g/g, and the growth rate, mu = 0.33 h(-1), were almost equal on soluble starch and on maltose, but on glucose no growth could be detected. An inhibitory effect of glucose, when added to other carbon substrates, also could not be found. Isobutyric and isovaleric acid were detected as novel metabolites produced by P. furiosus. Inhibitory effects of these acids, as well as of the well-known products acetic acid, propionic acid, and alanine, could be precluded. Concentrations of 10% CO2 in the gas supply respective to the exhaust gas enhanced the growth of P furiosus significantly. The maximum cell number was two orders of magnitude higher than was observed with pure nitrogen. Further increase of the CO2 concentration up to 100% had no significant effect on the growth of P. furiosus.  相似文献   

17.
We biometrically analyzed the body weight growth data of new-born squirrel monkeys, obtained during the nursing period from 0 to 12 weeks of age. Body weight (y in grams) could be expressed as a function of birth weight (a in grams) and age (x in weeks) by the following equation: y = a + b x, where b indicates growth rate. This equation corresponded significantly with actual growth curves (R2 = 0.96). The frequency distribution of b values was demonstrated to be abnormal distribution. This value was used to judge whether the body weight growth of each monkey was normal or abnormal. The lower control limit (LCL) was calculated by using a linear equation with the b value of 9.07 (M-1.25 x S.D.) and each birth weight. For the monkeys whose body weight was above the LCL during the first three weeks after birth, it was determined whether the frequency of weighings could be reduced from 13 to 7. Using the same animals, no significant difference was detected between the b value estimated from 13 measurements and that estimated from 7 measurements. Thus, from the standpoint of management's policy to save labor, the frequency of weighings could be reduced. A new daily routine has been established in our primate center to save labor by reducing the number of body weighings of the many infant monkeys. In the new program, newborn monkeys whose body weight is above the LCL are weighed only 7 times during the nursing period of 12 weeks, while those whose weight is below the LCL are weighed 8 to 13 times.  相似文献   

18.
余蓉培  李杨  李东  詹选怀  石雷 《植物学报》2015,50(5):565-572
以荚果蕨(Matteuccia struthiopteris)绿色球状体(GGB)为辐照材料,使用不同剂量的~(60)Coγ射线进行辐照处理,采用辐射诱变和组织培养技术相结合的方式进行荚果蕨GGB的辐射敏感性研究。结果表明,荚果蕨GGB的存活率与~(60)Coγ射线辐照剂量之间存在显著的线性关系,线性回归方程为:y=-0.797x+104.719,计算得到半致死剂量约为69 Gy。随着辐照剂量的增加,荚果蕨GGB的增殖和分化能力下降且分化时间延长。GGB~(60)Coγ辐射的表型损伤表现为颜色变深、单个绿色颗粒死亡、增殖及分化受到抑制;细胞学损伤表现为微核、细胞核解体和胚性细胞减少。  相似文献   

19.
桃小食心虫在不同温度下的实验种群生命表   总被引:10,自引:1,他引:10  
为探索温度对桃小食心虫Carposina sasakii生长发育和繁殖的影响,在室内17, 20, 23, 26, 29和32(±1) ℃,80%±7% RH和15L: 9D条件下,测定了桃小食心虫各发育阶段的历期、存活率和/或产卵量, 组建了桃小食心虫的实验种群生命表.结果表明, 桃小食心虫各虫态的发育历期随温度的升高而缩短; 初孵幼虫的蛀果率随温度升高而提高,幼虫脱果率与温度之间呈抛物线关系:y=-0.5638x2+27.882x-269.18 (R2=0.9801,P<0.01);结茧率和羽化率在17~29℃间无明显变化,但在32℃时则明显降低;雌蛾的产卵量和寿命随温度的升高而降低,23℃时雌蛾交配率最高.生命表分析表明,种群趋势指数在17~29℃间均大于1,26℃时内禀增长率最高;世代存活率与温度的关系可用S=-0.073x3+4.626x2-92.019x+596.57(R2=0.9832)表示; 内禀增长率与温度之间的关系可用rm=-0.0008x2+0.0409x-0.4438(R2=0.9851)描述。 据此得出,23~26℃是最适宜桃小食心虫生长发育和繁殖的温度范围。  相似文献   

20.
We have investigated the effects of maternal undernutrition during late gestation on maternal and fetal plasma concentrations of leptin and on leptin gene expression in fetal perirenal adipose tissue. Pregnant ewes were randomly assigned at 115 days of gestation (term = 147 +/- 3 days [mean +/- SEM]) to either a control group (n = 13) or an undernourished group (n = 16) that received approximately 50% of the control diet until 144-147 days of gestation. Maternal plasma glucose, but not leptin, concentrations were lower in the undernourished ewes. A significant correlation was found, however, between mean maternal plasma leptin (y) and glucose (x) concentrations (y = 2.9x - 2.4; r = 0.51, P < 0.02) when the control and undernourished groups were combined. Fetal plasma glucose and insulin, but not fetal leptin, concentrations were lower in the undernourished ewes, and no correlation was found between mean fetal leptin concentrations and either mean fetal glucose or insulin concentrations. A positive relationship, however, was found between mean fetal (y) and maternal (x) plasma leptin concentrations (y = 0.18x + 0.45; r = 0.66, P < 0.003). No significant difference was found in the relative abundance of leptin mRNA in fetal perirenal fat between the undernourished (0.60 +/- 0.09, n = 10) and control (0.70 +/- 0.08, n = 10) groups. Fetal plasma concentrations of leptin (y) and leptin mRNA levels (x) in perirenal adipose tissue were significantly correlated (y = 1.5x +/- 0.3; r = 0.69, P < 0.05). In summary, the capacity of leptin to act as a signal of moderate maternal undernutrition may be limited before birth in the sheep.  相似文献   

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