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21.
Intraspecies competition in a field population of Gregopimpla himalayensis (Hym.: Ichneumonidae) parasitic on the prepupae of Malacosoma neustria testacea (Lep.: Lasiocampidae) was investigated. The parasite oviposits the sufficient number of progeny (5 individuals/0.1 g dry weight of host) to exhaust a single host in a single attack. However, at the intensity less than 22–26 individuals/0.1 g d.w. of host, all individuals can emerge, i.e. density-dependent mortality does not occur. Within this range of intensity, survival of parasite larvae is guaranteed by diminution in body size and decreasing sex ratio. In contrast, total biomass of parasites showed a peak at 5 individuals/0.1 g d.w. of host at which a single host is exhausted. Above the intensity of 22–26, extraordinary minute individuals appeared and they died before maturation. If intraspecies competition play a role in regulation of G. himalayensis population in the field, the process is usually not through density-dependent mortality but through decreasing reproductive rate caused by decrease in the sex ratio, adult longevity and fecundity.  相似文献   
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ObjectivesTo analyze the growth trends of children in Beijing from 1955 to 2010.MethodsData for the period 1955–1975 were derived from published records. Data for the period 1985–2010 were derived from the Chinese National Survey on Students’ Constitution and Health (CNSSCH). Since 1985, the overall sampling and measurement methods have been consistent. The mean, the standard deviation, and the variance (ANOVA) of height, weight, and BMI by age and sex of students aged 7–17 were calculated and analyzed.ResultsBetween 1955 and 2010, the average height and weight of children in Beijing has increased. The average increments per decade for boys and girls were 2.45 cm and 2.03 cm in height and 2.68 kg and 1.68 kg in weight, respectively. The largest height increase per decade occurred between 1975 and 1985: 4.51 cm and 3.23 cm for boys and girls, respectively. The largest height increase for the entire 55-year period under study occurred among boys at age 13 (17.85 cm) and among girls at age 11 (15.90 cm.)ConclusionsDuring the period 1955–2010, growth trends among children in Beijing were positive. The health and nutritional status of these children improved significantly. Since 2007, might be related to government intervention, childhood obesity has been curbed.  相似文献   
24.
Thiazolidinediones (TZDs) are currently the most efficacious class of oral antidiabetics. However, they carry the burden of weight gain and haemodilution, which may lead to cardiovascular complications. The present study was designed to ascertain whether a combination of dipeptidyl peptidase IV (DPP IV) inhibitor with low dose of a thiazolidinedione absolves TZD associated weight gain and oedema without compromising its efficacy. In this study, we examined the efficacy and safety of lower dose (1 mg/kg/day) of rosiglitazone, a thiazolidinedione, in combination with 5 mg/kg/day dose of LAF-237 (vildagliptin), a known DPP IV inhibitor, in aged db/db mice after 14 days of treatment and compared the combination with therapeutic dose (10 mg/kg) of rosiglitazone. The combination therapy showed similar efficacy as that of 10 mg/kg/day rosiglitazone in lowering random blood glucose (53.8%, p<0.001 and 54.3%, p<0.001 respectively), AUC ((0-120) min) during oral glucose tolerance test (OGTT) (38.6 %, p<0.01; 38.3%, p<0.01 respectively) and triglyceride levels (63.9% and 61% respectively; p<0.01). Plasma active glucagon like peptide-1 (GLP-1) and insulin levels were found to be elevated significantly (p<0.01 and p<0.05 respectively) in both LAF-237 and combination treated groups following oral glucose load. LAF-237 alone had no effect on random glucose and glucose excursion during OGTT in severely diabetic db/db mice. Interestingly, the combination treatment showed no significant increase in body weight as compared to the robust weight gain by therapeutic dose of rosiglitazone. Rosiglitazone at 10 mg/kg/day showed significant reduction (p<0.05) in haematocrit, RBC count, haemoglobin pointing towards haemodilution associated with increased mRNA expression of Na(+), K(+)-ATPase-alpha and epithelial sodium channel gamma (ENaCgamma) in kidney. The combination therapy escaped these adverse effects. The results suggest that combination of DPP IV inhibitor with low dose of thiazolidinedione can interact synergistically to represent a therapeutic advantage for the clinical treatment of type 2 diabetes without the adverse effects of haemodilution and weight gain associated with thiazolidinediones.  相似文献   
25.
The objective of the research was to examine the effects of loading and posture on motoneuronal excitability of the triceps surae (TS) for patients with hemiplegia. Twelve healthy subjects and 12 patient subjects with post-stroke hemiparesis (onset period: 3–60 months) were enrolled in this study. The subjects were instructed to remain in quiet sitting with the test knee straight and three standing conditions of different superincumbent loads by shifting body weight to the test leg (10%, 50%, and 90% of body weight), while the H reflexes and M waves of the TS were measured. The results clearly indicated that H reflex amplitudes were not affected by different loading conditions in standing for both healthy subjects and patients who had a previous stroke. In addition, the H reflex amplitude in quiet standing for healthy subjects was significantly downward modulated relative to that in relaxed sitting with the test knee straight, but this posturally driven modulation was impaired in patients following stroke. Current electrophysiological findings imply that body weight as a means for rehabilitation facilitation had little immediate effect on paretic TS, and absence in postural gating of reflex excitability appeared to be an incentive for postural instability resulting from post-stroke hemiparesis.  相似文献   
26.
Independent studies with GM-CSF−/− mice have concluded that GM-CSF is necessary for normal reproductive outcome and for the maintenance of normal weight. In contrast to the literature we report that GM-CSF−/− and wild type (C57Bl/6) mice over a continuous 12 month period had similar litter size and neonatal survival. Likewise, unlike a literature observation, for the two mouse strains both male and female mice had similar weight gain when fed on a normal chow diet and monitored until 30 weeks of age. It is concluded that GM-CSF is not necessary for an optimal fertility outcome or for normal weight maintenance during development.  相似文献   
27.
Carrageenan was isolated under different extraction conditions from Kappaphycus alvarezii collected in North Sulawesi, Indonesia. Its gel properties include very strong elasticity even at low concentrations. Molecular weight and rheological properties were obtained by gel permeation chromatography and dynamic viscoelasticity measurements in order to clarify the average molecular weight at various extraction temperatures (50, 70, 90°C) and times (1, 3, 5 h), as well as gel formation ability. The results showed that both the weight-average and the number-average molecular weight decreased with increasing extraction temperature. However, the gelation rate of the carrageenan was found to be constant at around 40°C, whereas the storage modulus, G′, and loss modulus, G″, of the gels differed from each other.  相似文献   
28.
We employ a unique dataset of Major League Baseball (MLB) players - a select, healthy population - to examine trends in height, weight, and body mass in birth cohorts from 1869 to 1983. Over that 115-year time period, U.S. born MLB players have gained, on average, approximately 3 in. (7.6 cm) in height and 27.0 lb (12.2 kg) in weight, which has contributed a 1.6-unit increase in the body mass index. Where comparable data are available, U.S. born MLB players are about 2.0 in. (5.1 cm) taller and 20.0 lb (9.1 kg) heavier but substantially less obese than males in the general U.S. population. But both groups exhibit similar height and weight trends; the majority of height and weight gains take place in cohorts that were born prior to World War II, followed by slower gains and occasional declines in height and weight for cohorts born in 1939 and later.  相似文献   
29.
Exogenous melatonin as subcutaneous 2.7-mg implants was given to eight female and male minks in late July with an equal number of animals in the control groups. The liver enzyme activities and major lipids of liver and plasma were measured in October-November. Melatonin had very pronounced effects on the lipid and carbohydrate metabolism of the minks and there was also a clear sexual dimorphism. In the males, melatonin decreased the lipase esterase activity of the liver. In the liver of the females, however, melatonin increased the glucose-6-phosphatase activity. Due to melatonin treatment the liver triacylglycerol contents diminished in both sexes. At the same time, in the females the liver cholesterol levels were decreased. In the plasma lipids, the only change was a fall in the polar lipids of the melatonin-treated females. Melatonin seems to be responsible for the metabolic changes associated with the onset of wintering, especially for the acceleration of the deposition of subcutaneous fat reserves. The smaller females experience the effects of exogenous melatonin more rapidly than the males. Perhaps the smaller body size requires an earlier onset of metabolic preparation for the winter.  相似文献   
30.
Early 3rd instarDiacrisia obliqua Walk. larvae were treated with concentrations ofBacillus thuringiensis var.kurstaki (Dipel®) and the growth of treated larvae was assessed. All the doses reduced significantly the weight and survival of the insects (p<0.001).  相似文献   
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