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61.
One of the most important factors affecting survival rate of ovarian follicles during transplantation period is proper vascular development. The objective of the study was to evaluate the effect of vascular endothelial growth factor (VEGF) on auto-transplanted ovarian tissue. Twenty-one-day-old female mice (n?=?30) transplanted as control group and 21-day-old female mice (n?=?40) were divided into 4 groups that were treated with 0.5, 1, 2 and 4?µg/mL of VEGF directly injected to auto-transplanted ovarian tissue. Twenty-one days after transplantation, mice were treated with 7.5 IU pregnant mare serum gonadotropin and human chorionic gonadotropin. Transplanted ovaries were removed and sections were prepared from transplanted tissues for staining. The most effective dosage of VEGF on transplanted tissue was determined over H&;E (hematoxylin and eosin) staining results. Slides were compared using TUNEL staining and CD31 assay for the most effective dosage. The percentages of preantral and antral follicles were not significantly different between transplanted group with 4?µg/mL VEGF and non-transplanted group. Lower apoptotic areas and higher CD31 expression were observed in transplanted ovaries treated with 4?µg/mL VEGF when compared to transplanted ovaries without VEGF treatment. VEGF positively affects the quality of ovarian tissue during transplantation. Survival rate of follicles and follicular development has improved with the effect of VEGF.  相似文献   
62.
The monophyletic family Zhangsolvidae comprises stout‐bodied brachyceran flies with a long proboscis and occurring only in the Cretaceous, originally known in shale from the Early Cretaceous Laiyang Formation (Fm.) in China (Zhangsolva Nagatomi & Yang), subsequently from limestones of the Early Cretaceous Crato Fm. of Brazil. Cratomyoides Wilkommen is synonymized with Cratomyia Mazzarolo & Amorim, both from the Crato Fm.; Cratomyiidae is synonymized with Zhangsolvidae. Two genera and three species of Zhangsolvidae are described: Buccinatormyia magnifica Arillo, Peñalver & Pérez‐de la Fuente, gen. et sp.n. and B. soplaensis Arillo, Peñalver & Pérez‐de la Fuente, sp.n. , in Albian amber from Las Peñosas Fm. in Spain; and Linguatormyia teletacta Grimaldi, gen. et sp.n. , in Upper Albian–Lower Cenomanian amber from Hukawng Valley in Myanmar. Buccinatormyia soplaensis and Linguatormyia teletacta are unique among all Brachycera, extant or extinct, by their remarkably long, flagellate antennae, about 1.6× the body length in the latter species. A phylogenetic analysis of 52 morphological characters for 35 taxa is presented, 11 taxa being Cretaceous species, which supports placement of the family within Stratiomyomorpha, although not to any particular family within the infraorder. This published work has been registered in Zoobank, http://zoobank.org/urn:lsid:zoobank.org:pub:F32CF887‐7C37‐45D5‐BD6B‐135FE9B729A7 .  相似文献   
63.
The relationshipbetween myogenin or MyoD expression and hypertrophy of the rat soleusproduced either by clenbuterol and 3,3',5-triiodo-L-thyronine(CT) treatment or by surgical overload was examined. Mature female ratswere subjected to surgical overload of the right soleus with the leftsoleus serving as a control. Another group received the same surgicaltreatment but were administered CT. Soleus muscles were harvested 4 wkafter surgical overload and weighed. Myosin heavy chain isoforms wereseparated by using polyacrylamide gel electrophoresis while myogeninand MyoD expression were evaluated by Northern analysis.CT and functional overload increased soleus muscle weight. CT treatmentinduced the appearance of the fast type IIX myosin heavy chain isoform,depressed myogenin expression, and induced MyoD expression. However,functional overload did not alter myogenin or MyoD expression inCT-treated or non-CT-treated rats. Thus pharmacologically andsurgically induced hypertrophy have differing effects on myogenin andMyoD expression, because their levels were associated with changes inmyosin heavy chain composition (especially type IIX) rather thanchanges in muscle mass.

  相似文献   
64.
In this paper we report about a screening for streptothricin- (St)-resistant phenotypes and genotypes among environmental bacteria from a St virgin area. St-resistant bacteria were isolated from river water, sewage, manure and soil by selective plating. The resistance quotient was typical of an area without selective pressure. The occurrence of streptothricin acetyltransferase-encoding determinants and their localization on a Tn7-like transposon was tested by the application of a set of gene probes. Sat genes could be detected in 22.5% of the tested St-resistant bacteria but in 100% of the checked Enterobacteriaceae. However, we could not detect sat genes in St-resistant bacteria from soil samples. Surprisingly the sat genes were found to be located on conjugative or mobilizable plasmids for a rather high number of strains. The determined plasmid species and their restriction patterns showed a high degree of similarities to those observed from an area of strong selective pressure.  相似文献   
65.
A UV reactor with an annular design, a total liquid volume of 460[emsp4 ]ml, and outfitted with a single lamp with 1690[emsp4 ]mW of germicidal power was tested. Coliphage MS2 was used as a bioactinometer to measure the UV dose at a flow rate of 56.7[emsp4 ]ml/sec in water with a very low absorbance. The Beers Law coefficient was A100.003. The measured dose (MS2 bioactinometry) was 35.2±1.1[emsp4 ]mW-sec/cm2.A retention time distribution was generated with a dye tracer study. The reactor was modeled as if flow was confined to ten equal volume paths existing as concentric rings around the lamp. The UV intensity along each path (ith intensity) was calculated to generate a simulated distribution of UV intensity in the reactor. The retention time distribution was subdivided to estimate the retention time associated with each decile jth time) of the total flow.Seven methods of associating the ith intensity with the jth retention time were used to produce simulated dose distributions for the reactor. The average UV dose for each distribution was calculated as the average of the products of I and t (AP protocol) and by the apparent survival (AS protocol), in which the predicted survival along each path was averaged to back-calculate dose from the reference batch inactivation curve. The average dose predicted assuming that time and intensity were independent was 51.5[emsp4 ]mW-sec/cm2 based on the arithmetic average (AP protocol). Using the apparent survival method, the predicted dose for the independent distribution (I independent of t) was 36.4[emsp4 ]mW-sec/cm2. Three methods of developing dependent structure between time and intensity were tested. In the best possible case for stratified flow (I negatively correlated with t) the calculated (AS) intensity was 46.3[emsp4 ]mW-sec/cm2. In the worst case for stratified flow (I positively correlated with t) the AS intensity was 32.0[emsp4 ]mW-sec/cm2. In a rational case where flows were assumed to be distributed parabolically (low flow at the wall and at the lamp) produced an AS intensity of 37.7[emsp4 ]mW-sec/cm2. When either time or intensity was averaged, while the other variable was allowed to keep its distribution, the (AS) dose (time averaged 43.3[emsp4 ]mW-sec/cm2, intensity averaged 41.0[emsp4 ]mW-sec/cm2), yielded a poor prediction compared to the measured value.The errors associated with averaging time, intensity, or both, far outweigh the errors associated with choosing a rational distribution or an independent distribution of time and intensity in the prediction. This observation is generally true whenever an organism is exposed to UV light in a flow through reactor such that the range of doses is within the portion of the inactivation curve exhibiting strong exponential decay.  相似文献   
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