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1.
Activation and inactivation of fat body glycogen phosphorylase was investigated in ligated abdomens of larval Manduca sexta and in vitro. After maximal activation through Manduca adipokinetic hormone (AKH) or chilling, inactivation of glycogen phosphorylase commenced as soon as the stimulus for the activation was removed indicating that the enzyme system in the fat body is fine-tuned to low phosphorylase activities which is necessary to allow glycogen synthesis. In intact ligated abdomens phosphorylase can be activated repeatedly by either stimulus showing that the fat body system does not lose its responsiveness. It was impossible to achieve complete conversion of the inactive form of phosphorylase into the active form even after administration of AKH and simultaneous chilling. © 1992 Wiley-Liss, Inc.  相似文献   
2.
Blue crabs Callinectes latimanus (Rath.) trapped from two lagoons were sexed, measured and weighed. The eggs of the mature females were counted to determine fecundity, and the spermatophores of the males were counted to determine the size of sexual maturity. Sizes at maturity of both male and female crabs were determined. The methods employed and the results are discussed.  相似文献   
3.
The rate of oxygen uptake and the amount of several main cell constituents were determined in NPV-infected and uninfected isolated pupal abdomens of the silkworm, Bombyx mori. The oxygen uptake in uninfected isolated abdomens increases for the first 2 days due to the effect of water injection, but thereafter it remains almost unchanged at a relatively low level. When isolated abdomens are infected with an NPV, the oxygen uptake increases markedly from 3 days postinfection onward, being about three times that of uninfected isolated abdomens at late stages of infection. The amounts of cell constituents analyzed in the present study change little in uninfected isolated abdomens throughout the experiment. Infection of NPV leads to a marked accumulation of both DNA and RNA, and a loss of glycogen. The amount of protein, lipid, and sugar are scarcely affected by NPV infection. These results indicate that the activity of metabolism in uninfected isolated abdomens is not only low but also stable, and that infection of NPV results in an activation of host cell metabolism. It is considered that such isolated pupal abdomens provide an excellent opportunity to analyze both the process of NPV replication and the alteration of host cell metabolism resulting from NPV infection.  相似文献   
4.
《Fly》2013,7(4):240-245
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5.
The abdominal hollowing technique is used for training the transversus abdominis (TrA). However, the optimal intensity of hollowing is still unclear. The objective of the present study is to verify the validity of estimating the tension of the TrA by measuring the girth of the abdomen with a tape and to determine the optimum intensity of hollowing to effectively train the TrA. Sixteen healthy males performed hollowing with an intensity of 0%, 25%, 50%, 75%, and 100%, estimated from the girth of the abdomen. The shear elastic modulus was measured for the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and TrA at all intensities via ultrasonic shear wave elastography. The shear elastic modulus was considered as the index of the tension of the abdominal muscles at each intensity, and the ratio of the TrA to RA, EO, and IO respectively was calculated as the index of TrA selectivity. As the intensity of hollowing increased, the girth of abdomen decreased and tension of all the four muscles increased. The ratio of TrA to the RA, EO, and IO did not exhibit a significant variation among hollowing intensities of 25% to 100%. It is rational to estimate the tension of the TrA by measuring the girth of the abdomen. Moreover, considering both TrA contraction intensity and selectivity, abdominal hollowing performed at maximum intensity was effective for the maximum contraction training of the TrA.  相似文献   
6.
目的:探讨CT平扫对肠坏死诊断价值,总结肠管坏死征象。方法:分析98例可疑肠坏死患者CT平扫图像,所有患者均经手术证实或未能及时治疗死亡患者CT平扫影像,总结、分析影像特点。结果:全部患者中40例患者存在肠坏死,肠壁厚度改变,包括29例肠壁增厚,8例肠壁菲薄,5例表现为肠壁密度减低,3例表现为肠壁密度增加,25例表现肠管扩张,8例表现肠管塌陷,36例肠管内积液,其中34例见气液平面,4例仅见积气,5例肠壁内见气泡影,38例见腹腔积液,10例见系膜水肿,2例见肠系膜血管密度增高,1例肠系膜静脉内气体,1例门静脉内气体,5例见腹腔游离气体。结论:多排螺旋CT平扫对肠坏死部位及范围的评价有较高的价值,同时CT平扫能明确病因,为及早治疗打下良好基础。  相似文献   
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8.
Understanding the evolutionary potential of morphological evolution is still a major problem in evolutionary biology. In this study, we tried to quantify the amount of variation of different traits among species of a Drosophila clade reared under standard conditions. Nineteen different traits have been measured on nine species of the same clade, the Neotropical saltans group of Drosophila. Measured traits can be distributed into five categories: size‐traits (wing and thorax), shape indices (ratios among the size traits), number of sternopleural bristles on the thorax, number of abdominal bristles on successive sternites, and dorsal pigmentation of abdomen. All species are of medium size with a generally dark pigmentation. A remarkable feature is the presence of numerous bristles on the 6th sternite of the males, while this segment is bare in other Drosophila species. A multivariate analysis revealed that it was possible to discriminate all the investigated species by using the complete set of measured traits. For each trait, phenotypic variability was investigated at the within‐ and between‐species levels. As a rule, the interspecific coefficient of variation (CV) was much greater than the within species CV, and it is proposed to call it realized evolvability. All possible correlations were calculated between traits across species, providing many unexpected results. Size traits were highly correlated among them, but not correlated with shape indices. Abdominal traits (bristles and pigmentation) were correlated, but often in opposite directions, with thoracic shape indices. Tergite pigmentation was negatively correlated with bristle number on sternite. For the moment, most of the correlations cannot be explained by developmental processes or parallel selective pressures. Nonetheless, mapping the evolution of the two characters on a molecular phylogeny of the studied species revealed two opposite phylogenetic trends for abdominal pigmentation and setation, respectively. Our data suggest a need for similar studies in other well‐defined Drosophila clades.  相似文献   
9.
目的:评价超声在诊断妊娠合并急腹症中的临床应用价值。方法:回顾分析686例妊娠合并急腹症患者的临床资料,总结妊娠合并急腹症超声图像特征。结果:超声诊断符合率为:异位妊娠87.2%(184/211),急性阑尾炎84.2%(32/39),卵巢囊肿蒂扭转90.0%(27/30),急性胰腺炎66.7%(6/9),不全流产及难免流产、子宫肌瘤扭转、子宫肌瘤红色变性、胎盘早剥、泌尿系结石、急性胆囊炎和胆结石、急性胃肠炎、急性肠梗阻的诊断率为100%(43/43)。结论:超声可以作为妊娠合并急腹症首选的检查手段,为临床早期诊断及治疗提供可靠依据。  相似文献   
10.
Effect of a high temperature on the development of nuclear polyhedrosis and nuclear polyhedrosis virus (NPV) was studied employing pupae and isolated pupal abdomens of the silkworm, Bombyx mori. It was shown that pupae inoculated with an NPV and incubated at 35°C survived longer than those incubated at 25°C. At lower dosages of virus, pupae at 35°C escaped death from NPV. When inoculated pupae were incubated at 35°C for varying periods and then transferred to 25°C, the longer the pupae had been kept at 35°C the longer they survived. In contrast, when inoculated pupae were transferred from 25° to 35°C, the longer the pupae had been kept at 25°C the sooner after inoculation they died. Essentially the same results were obtained in isolated abdomens which were in an arrested state of development, excluding the possibility that observed thermal inhibition of viral diseases is dependent upon the altered developmental processes at high temperatures. Virus titration experiments showed that, under experimental conditions utilized, no detectable accumulation of infectious NPV was present in abdomens inoculated with an NPV and incubated at 35°C. When inoculated abdomens were shifted up from 25° to 35°C at 3 days postinoculation, NPV accumulation was inhibited almost immediately, and when inoculated abdomens were shifted down from 35° to 25°C, infectious NPV started to accumulate as early as 1 day after the shift. It was also shown that the pattern of infectious NPV accumulation and that of nucleic acid increase in infected abdomens gave a rough correlation. These results indicate that the thermal inhibition of viral diseases is attributed, at least in part, to the restricted accumulation of infectious progeny and suggest that the virus replication mechanism itself is more sensitive to high temperatures than that related to other events necessary for viral replication to be initiated.  相似文献   
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