Mechanism and Behavioral Context of Male Sex Pheromone Release in <Emphasis Type="Italic">Nasonia vitripennis</Emphasis>

Males of the parasitic wasp Nasonia vitripennis (Hymenoptera: Pteromalidae) attract virgin females by releasing a sex pheromone composed of (4R,5R)- and (4R,5S)-5-hydroxy-4-decanolide (HDL). The pheromone is biosynthesized in the rectal vesicle of males. In the present study, we investigated the mechanism and behavioral context of pheromone release, and determined the range of activity and the longevity of the chemical signal. Our data show that the sex pheromone of N. vitripennis is substrate-borne and is deposited on surfaces by dabbing movements of the abdominal tip, a behavior previously described in N. vitripennis males as ‘abdomen dipping’. Chemical markings deposited by a single male were highly attractive to virgin females. Chemical analyses revealed the presence of HDL in surface washings of marked areas, and HDL amounts correlated with male marking activity. Pheromone deposition occurred spontaneously without any additional cues being present, but marking intensity increased greatly after copulation or after a single contact with a virgin female. In contrast, marking intensity was not influenced by the presence of host puparia. Male pheromone deposits were perceived by females in a still-air olfactometer at distances of up to 4.5 cm and remained attractive for at least 2 h. The function of the substrate-borne sex pheromone is discussed with respect to the mating system of N. vitripennis.     

超声检查在妇产科急腹症中的诊断价值

目的:对超声检查在妇产科急腹症中的诊断价值进行探讨。方法:对我院2011年至2012年间的70例妇产科急腹症进行回顾性分析,对患者的手术情况、病理以及超声检查结果进行对比分析。结果:在诊断的过程中,异位妊娠的诊断率为97.37%,卵巢囊肿蒂扭转的诊断率为100%,黄体破裂的诊断率为92.31%,胎盘早剥的诊断率为100%,急性盆腔炎的诊断率为100%,其总诊断率为97.14%。结论:超声检查在妇产科急腹症的诊断过程中具有很高的诊断率,这对于患者的治疗提供了重要的参考,值得临床推广。     

Dual-contrast single breath-hold 3D abdominal MR imaging

Object: Multiple contrasts are often helpful for a comprehensive diagnosis. In 3D abdominal MRI, breath-hold techniques are preferred for single contrast acquisitions to avoid respiratory artifacts. In this paper, highly accelerated parallel MRI is used to acquire large 3D abdominal volumes with two different contrasts within a single breath-hold. Material and methods: In vivo studies have been performed on six healthy volunteers, combining T ₁- and T ₂-weighted, gradient- or spin-echo based scans, as well as water/fat resolved imaging in a single breath-hold. These 3D scans were acquired with an acceleration factor of six, using a prototype 32-element receive array. Results: The presented approach was tested successfully on all volunteers. The whole liver area was covered by a FOV of 350 × 250 × 200 mm³ for all scans with reasonable spatial resolution. Arbitrary scan protocols generating different contrasts have been shown to be combinable in this single breath-hold approach. Good spatial correspondence with negligible spatial offset was achieved for all different scan combinations acquired in overall breath-hold times between 15 and 25 s. Conclusion: Enabled by highly parallel imaging technology, this study demonstrates the technical feasibility and the promising image quality of single breath-hold dual contrast MRI.     

Free-form image registration regularized by a statistical shape model: application to organ segmentation in cervical MR

Deformable registration is prone to errors when it involves large and complex deformations, since the procedure can easily end up in a local minimum. To reduce the number of local minima, and thus the risk of misalignment, regularization terms based on prior knowledge can be incorporated in registration. We propose a regularization term that is based on statistical knowledge of the deformations that are to be expected. A statistical model, trained on the shapes of a set of segmentations, is integrated as a penalty term in a free-form registration framework. For the evaluation of our approach, we perform inter-patient registration of MR images, which were acquired for planning of radiation therapy of cervical cancer. The manual delineations of structures such as the bladder and the clinical target volume are available. For both structures, leave-one-patient-out registration experiments were performed. The propagated atlas segmentations were compared to the manual target segmentations by Dice similarity and Hausdorff distance. Compared with registration without the use of statistical knowledge, the segmentations were significantly improved, by 0.1 in Dice similarity and by 8 mm Hausdorff distance on average for both structures.     

腹部闭合性肝损伤30例诊治分析

目的了解腹部闭合性肝损伤的治疗方法,总结临床治疗闭合性肝损伤的经验。方法对30例腹部闭合性肝损伤患者的临床诊治资料进行回顾性分析。结果手术治疗组与非手术治疗组在治愈率,并发症发生率及输血量上均存在显著差异,P<0.05。结论非手术治疗对Ⅰ-Ⅱ级肝损伤的治疗效果比较突出,而手术治疗对Ⅲ级以上的肝损伤的治疗效果较好。     

宫高腹围法预测巨大儿准确性的影响因素分析

目的探讨影响宫高腹围法预测巨大胎儿准确性的因素。方法选择2000～2006年在我院剖宫产出生的巨大儿1090例,产前测量宫高、腹围,以9种方法分别估算胎儿体重,与其出生体重相比较,计算符合率,同时观察胎儿孕龄、性别及孕母身高等因素对预测准确性的影响。结果经验法、罗来敏算法等5种方法对巨大儿的预测符合率超过50%,其中罗来敏算法的预测符合率达66.1%,而颜贞淑法的符合率最低,仅13.8%。胎儿孕龄和性别对预测准确性影响不大。罗来敏算法、袁冬生法等5种方法预测巨大儿体重的误差随孕母身高的增加逐渐减小。结论罗来敏算法、经验法等预测巨大儿准确性较高,颜贞淑法用于预测巨大儿准确性较差,建议不予采用,孕母身高可影响巨大儿体重预测的误差。