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981.
982.
983.
The sexual cycle of the cuttlefish, Sepia officinalis, fromthe northern part of the Bay of Biscay was followed over severalyears (1988 to 1990 and 1992 to 1993). Successive maturity stagesare reached at the same time regardless of site in the northernpart of the Bay. In this area, the majority of cuttlefish reproduceduring their second year of life (group II) whereas the remainderreproduce in their first year (group I). The first visible signsof sexual development concern the testis in males and the genitaltract in females. Males mature earlier than females: the firstspermatophores appear in July (group II) and October (groupI) while mature eggs appear from December (group II) and March(group I). The breeding season lasts from about mid-March tolate June (3.5 months). (Received 2 February 1996; accepted 30 May 1996)  相似文献   
984.
The paper is devoted to an analysis of combined x-ray findings supplemented by CT findings in patients with sarcoidosis detected for the first time with early signs of this disease. A conclusion has been made that apart from lymph node enlargement, sarcoidosis is characterized by lung parenchymal changes which manifest themselves as symptoms of broncho-alveolitis. Characteristic x-ray symptom complexes are described. Roentgeno-semiotics of these changes were compared with the results of morphological investigation of transbronchial puncture specimens. Roentgenologically detectable changes showed good correlation with morphology findings. The authors have also emphasized the importance of morphological verification of this disease at early stages.  相似文献   
985.
986.
Age peculiarities in composition of the upper tracheobronchial lymph nodes have been studied in 60 corpses at the age of 16-70 years. Cause of death has not been connected with diseases of blood, lymphatic system or thoracic origins. Routine histological and morphometric methods have been applied. Certain age-dependent rearrangement in the connective tissue stroma, trabecular vegetations and differences in correlations of structural components have been noted. A rather essential volumetric increase of the medullary substance takes place at the level of hilus of the lymph node. Cellular composition of the lymph nodes is greatly polymorphous but is more or less constant for each age group. The number of macrophages containing carbon pigment is increasing with age.  相似文献   
987.
临床决策能力是一个医生的必备能力之一,是医学教育中必要且重要的培养目标之一。目前对医学生临床决策能力的培养没有形成完备的体系,一般安排在高年级阶段进行,为时较晚。如何把临床决策能力的培养融入低年级基础课中,以尽早开展能力训练值得探索研究。本研究以医学遗传学课程为例,结合探究式教学方式的特点,模拟临床决策思维过程的各细分模块,优化了课程设计,探索在低年级课程中融入临床决策能力的培养。结果提示:探究式课程设计能充分调动学生主动性,增加学生分析、思考的投入;在教师引导下,促使学生依循临床决策思维的过程得到有效地训练。最后,整理分析了探究式课程设计及实践的思路,总结了设计原则和要点,反思了教学中的经验得失。  相似文献   
988.
The aim of this research was to select plant species that could be effective in the phytoremediation of a former oil-sludge pit. Seven crop plants (Triticum aestivum L., Secale cereale L., Avena sativa L., Hordeum vulgare, Sorghum bicolor L. Moench, Panicum miliaceum L., and Zea mays L.), five wild grasses (Lolium perenne L., Bromopsis inermis, Agropyron cristatum L., Agropyrum tenerum L., and Festuca pratensis Huds.), and three legumes (Medicago sativa L., Trifolium pratense L., and Onobrychis antasiatica Khin.) were screened for phytotoxicity, including the assessment of germination, shoot biomass, and root biomass, in a pot experiment. The estimation of oil-sludge degradation in the root zone of the tested plants showed that rye accelerated cleanup most effectively, degrading all of the main contaminant fractions in the oil sludge by a total of 52%. Although alfalfa had a lower phytoremediation potential than did rye, it maintained large numbers of soil microorganisms, including polycyclic aromatic hydrocarbon degraders, in its rhizosphere. Rye and alfalfa were chosen for a large-scale study to remediate an oil-sludge pit on the grounds of a petroleum refinery. Remediation monitoring confirmed the effectiveness of rye: the oil-sludge content decreased consistently for 3 years and remained low in comparison with the results from other plant species.  相似文献   
989.
丹酚酸B对高糖日粮小鼠消化系统自由基水平的影响   总被引:1,自引:0,他引:1  
本文研究了丹酚酸B(salvianolic acid B,Sal B)对灌注及长期摄食高糖小鼠活性氧自由基(reactive oxygen species,ROS)的影响.结果表明:灌胃高糖使小鼠全血ROS于1.5 h达到最大值,灌胃葡萄糖的ROS释放量显著高于蔗糖(P<0.05);灌胃高糖使小鼠血糖浓度于0.5 h达到最高,灌胃葡萄糖的小鼠血糖浓度有高于灌胃蔗糖的小鼠血糖浓度的趋势(P>0.05);添加Sal B后并没有改变灌胃高糖小鼠的全血ROS释放和血糖浓度变化趋势,但有降低血糖趋势(P>0.05),显著减少了ROS的释放量(P<0.05);添加Sal B后显著降低长期高糖膳食小鼠的全血、肝脏、胰腺、胃、十二指肠、空肠和回肠的ROS释放量.  相似文献   
990.
An artificial membrane system was adapted to feed Ornithodoros turicata (Ixodida: Argasidae) larvae from a laboratory colony using defibrinated swine blood. Aspects related to larval feeding and moulting to the first nymphal instar were evaluated. A total of 55.6% of all larvae exposed to the artificial membrane in two experimental groups fed to repletion and 98.0% of all fed larvae moulted. Mortality rates of first instar nymphs differed significantly depending on the sorting tools used to handle engorged larvae (χ2 = 35.578, P < 0.0001): engorged larvae handled with featherweight forceps showed significantly higher mortality (odds ratio = 4.441) than those handled with a camel‐hair brush. Differences in the physical properties of the forceps and camel‐hair brush may affect the viability of fragile soft tick larvae even when care and the same technique are used to sort them during experimental manipulations. The current results represent those of the first study to quantify successful feeding to repletion, moulting and post‐moulting mortality rates in O. turicata larvae using an artificial membrane feeding system. Applications of the artificial membrane feeding system to fill gaps in current knowledge of soft tick biology and the study of soft tick–pathogen interactions are discussed.  相似文献   
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