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161.
将一株分离自木榄根际土壤的菌株F5鉴定为曲霉属环绕组真菌成员,其在形态学特征和ITS序列上与Aspergillus ochraceopetaliformis极为相似。该菌株在改良葡萄糖蛋白胨酵母培养基(GPYM)中28℃下160r/min发酵7d后的产物具有明显的抑菌活性。利用色谱方法从菌株F5的发酵产物中分离鉴定到2种化合物:(R)-(-)-mellein(Ⅰ)和flavacol(Ⅱ),其中,flavacol对枯草芽孢杆菌的生长具有明显的抑制作用,最低抑菌浓度(MIC)为32mg/L,而mellein对金黄色葡萄球菌和枯草芽孢杆菌的生长均无明显的抑制活性。 相似文献
162.
Stepan H Scheithauer S Dornhöfer N Krämer T Faber R 《Obesity (Silver Spring, Md.)》2006,14(5):770-773
Objectives: Obesity before and during pregnancy is associated with several obstetrics risk factors for both mother and fetus. The aim of this retrospective study was to analyze the influence of BMI before pregnancy on distinct perinatal parameters. Research Methods and Procedures: The study includes 5067 singleton pregnancies from 2001 to 2004 at the Department of Obstetrics and Gynecology, University of Leipzig. The study group was divided into BMI groups: <18.5, ≥18.5 to <25, ≥25 to <30, ≥30 to <35, ≥35 to <40, and ≥40 kg/m2. Analysis of perinatal data included rate of intrauterine death, rate of cesarean section and shoulder dystocia, time of hospital stay for mother and newborn, and gestational age of delivery. Neonatal outcome variables included percentage of newborns weighing >4000 grams, rate of umbilical cord pH <7.10, and rate of 1‐, 5‐, and 10‐minute Apgar scores of <8. Results: There was no difference in the gestational age at delivery among the groups. In the group with BMI ≥30 kg/m2, the cesarean section rate was significantly elevated to 25.1%, with a more dramatic increase up to 30.2% in the group with BMI ≥35 kg/m2 and 43.1% in the group with BMI ≥40 kg/m2, mainly because of a higher number of secondary cesarean sections. Although newborns of obese women showed worse initial neonatal adaptation, the 10‐minute Apgar values did not differ among the groups. The higher rate of operative deliveries and the trend to an increased rate of shoulder dystocia did not influence duration of the hospital stay for mothers and newborns or morbidity of both. Discussion: A high pre‐pregnancy BMI is clearly associated with a higher rate of cesarean section deliveries. However, under the compensating conditions of a tertiary perinatal center, overall morbidity of mothers and newborns seems not to be increased. 相似文献
163.
重点描述宜昌黄花场剖面中 /下奥陶统界线附近的重要牙形剌共 3属、5种和 2新种Bergstroe mognathussp .nov .,BaltoniodustetrachotomusLiandWangsp .nov .,并对Oepikodusevae带和Baltoniodustriangu laris带分子的首现位置及带的含义进行厘定。作者还在此剖面大湾组下段发现北美中大陆区暖水型牙形剌Tripoduslaevis和Protoprioniodusaranda ,并确定Tripoduslaevis的首现位置在Baltoniodustriangularis带底界之上 0 .3m处。Tripoduslaevis的首次出现曾提议为中奥陶统的底界的标志 (见陈旭等 ,2 0 0 0 ) ,在宜昌黄花场剖面上Tripoduslaevis的首现位置接近Baltoniodustriangularis带底界 ,对确定中 /下奥陶统界线很重要。由于在黄花场剖面可识别出Baltonioduscrassulus—B .gladiatus—B .triangularis演化谱系 ,作者建议以B .triangularis的首次出现作为中奥陶统的底界 ,宜昌黄花场剖面为中 /下奥陶统界线的层型剖面。同时 ,文中将本区的牙形刺带与世界其它地区作了对比。 相似文献
164.
M. H. Amiri 《Journal of fish biology》1991,39(1):71-82
A continuous observation apparatus was used to study the responses of Phoxinus phoxinus melanophores to illuminated black/white backgrounds and their reversal. The fish. Although confined, showed maximum melanosome dispersion (MI 5) and maximum melanosome aggregation (MI 1) when exposed to illuminated black and white backgrounds respectively. Melanophores affected by spinal nerve section showed full melanosome dispersion and the affected area appeared as a black band. The affected melanophores marginally and gradually aggregated their melanosomes if the fish was exposed to an illuminated white background for about a week. The responses of these melanophores to illuminated black and white backgrounds and their reversal indicates that the dispersal of their melanosomes in response to a black background is much faster than their aggregation in response to a white background. It is concluded that an active mechanism is involved and possible factors controlling it are discussed. 相似文献
165.
The heterotrophic marine dinoflagellate genus Protoperidinium is the largest genus in the Dinophyceae. Previously, we reported on the intrageneric and intergeneric phylogenetic relationships of 10 species of Protoperidinium, from four sections, based on small subunit (SSU) rDNA sequences. The present paper reports on the impact of data from an additional 5 species and, therefore, an additional two sections, using the SSU rDNA data, but now also incorporating sequence data from the large subunit (LSU) rDNA. These sequences, in isolation and in combination, were used to reconstruct the evolutionary history of the genus. The LSU rDNA trees support a monophyletic genus, but the phylogenetic position within the Dinophyceae remains ambiguous. The SSU, LSU and SSU + LSU rDNA phylogenies support monophyly in the sections Avellana, Divergentia, Oceanica and Protoperidinium, but the section Conica is paraphyletic. Therefore, the concept of discrete taxonomic sections based on the shape of 1′ plate and 2a plate is upheld by molecular phylogeny. Furthermore, the section Oceanica is indicated as having an early divergence from other groups within the genus. The sections Avellana and Excentrica and a clade combining the sections Divergentia/Protoperidinium derived from Conica‐type dinoflagellates independently. Analysis of the LSU rDNA data resulted in the same phylogeny as that obtained using SSU rDNA data and, with increased taxon sampling, including members of new sections, a clearer idea of the evolution of morphological features within the genus Protoperidinium was obtained. Intraspecific variation was found in Protoperidinium conicum (Gran) Balech, Protoperidinium excentricum (Paulsen) Balech and Protoperidinium pellucidum Bergh based on SSU rDNA data and also in Protoperidinium claudicans (Paulsen) Balech, P. conicum and Protoperidinium denticulatum (Gran et Braarud) Balech based on LSU rDNA sequences. The common occurrence of base pair substitutions in P. conicum is indicative of the presence of cryptic species. 相似文献
166.
167.
168.
Paulina S. Nätscher Jana Gliwa Kenneth De Baets Abbas Ghaderi Dieter Korn 《Palaeontology》2023,66(4):e12667
The body size of marine ectotherms is often negatively correlated with ambient water temperature, as seen in many clades during the hyperthermal crisis of the end-Permian mass extinction (c. 252 Ma). However, in the case of ostracods, size changes during ancient hyperthermal events are rarely quantified. In this study, we evaluate the body size changes of ostracods in the Aras Valley section (northwest Iran) in response to the drastic warming during the end-Permian mass extinction at three taxonomic levels: class, order, species. At the assemblage level, the warming triggers a complete species turnover in the Aras Valley section, with larger, newly emerging species dominating the immediate post-extinction assemblage for a short time. Individual ostracod species and instars do not show dwarfing or a change in body size as an adaptation to the temperature stress during the end-Permian crisis. This may indicate that the ostracods in the Aras Valley section might have been exceptions to the temperature–size rule (TSR), using an adaptation mechanism that does not involve a decrease in body size. This adaptation might be similar to the accelerated development despite constant instar body sizes that can be observed in some recent experimental studies of ostracod responses to thermal stress. 相似文献
169.
摘要 目的:研究不同剂量舒芬太尼和纳布啡持续镇痛对剖宫产产妇术后镇痛和镇静效果的影响。方法:选取2020年1月到2021年12月在我院进行剖宫产分娩的产妇100例,根据术后镇痛使用舒芬太尼剂量的不同分为A组和B组,每组各50例。A组术后镇痛方案:1.0 μg/kg舒芬太尼和1 mg/kg纳布啡,持续镇痛48小时;B组术后镇痛方案:2.0 ?滋g/kg舒芬太尼和1 mg/kg纳布啡,持续镇痛48小时。比较两组术后不同时间视觉模拟量表(VAS)评分和Ramsay评分。结果:(1)两组患者年龄、身高、体重、孕周、麻醉起效时间、胎儿分娩时间、手术时间和麻醉时间比较均无显著差异(P>0.05);(2)B组产妇术后48小时收缩压、舒张压、心率和血氧饱和度均显著低于A组产妇(P<0.05);(3)B组产妇术后6、24和48小时VAS评分均显著低于A组(P<0.05),而Ramsay评分却显著高于A组(P<0.05);(4)B组产妇术后不良反应发生率高于A组(16% vs 12%),但比较无统计学意义(P>0.05)。结论:舒芬太尼和纳布啡持续镇痛对剖宫产产妇具有较好的术后镇痛和镇静效果,提高舒芬太尼剂量镇痛镇静效果更好。 相似文献
170.
Mikihiro Shamoto Masanori Shinzato Satoru Hosokawa Chiyuki Kaneko Takashi Hakuno Kazutaka Nomoto 《Virchows Archiv. B, Cell pathology including molecular pathology》1992,61(1):337-341
Cells immunostained with antibodies against both OKT-6 and S-100 protein were observed only in superficial and hilar lymph
nodes draining tissues with predominantly squamous epithelia. In contrast, in mesenteric lymph nodes and the spleen, only
S-100 protein-positive, but OKT-6-negative cells were found. We suspect that the S-100 and OKT-6-positive cells might be Langerhans
cells (LC) and the S-100-positive, OKT-6-negative cells, interdigitating reticulum cells (IDC). We further postulate that
the LC in superficial and hilar lymph nodes might migrate from squamous epithelia, with which contact is required for the
formation of Birbeck granules. 相似文献