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991.
992.
Abstract The structure of the secondary egg envelope of seven species of Cyprinodontidae belonging to the genus Epiplatys was observed by transmission and scanning electron microscopy. The transverse structure of the secondary envelope examined by transmission electron microscopy is a constant feature in all the species studied and represents a good criterion for identification. In contrast, the surface structure of the secondary envelope when observed by scanning electron microscopy exhibits a great diversity of form. It is possible to distinguish each of the seven different species by the pattern of ornamentation, the width of the polygons and the size of the granules comprising them on the secondary egg envelope. 相似文献
993.
An ultrastructural study of the manchette was carried out on 21 species belonging to the culicid genera Aedes, Anopheles, Culex and Toxorhynchites . Each genus has a characteristic morphological type of manchette. Toxorhynchites seems to have the type found in many other Diptera, while the other genera have unusual types. 相似文献
994.
Endurance training affects myosin heavy chain phenotype in regenerating fast-twitch muscle 总被引:2,自引:0,他引:2
Bigard Xavier A.; Janmot Chantal; Merino Daniele; Lienhard Francoise; Guezennec Yannick C.; D'Albis Anne 《Journal of applied physiology》1996,81(6):2658-2665
Bigard, Xavier A., Chantal Janmot, Danièle Merino,Françoise Lienhard, Yannick C. Guezennec, and Anne D'Albis.Endurance training affects myosin heavy chain phenotype inregenerating fast-twitch muscle. J. Appl.Physiol. 81(6): 2658-2665, 1996.The aim of thisstudy was to analyze the effects of treadmill training (2 h/day, 5 days/wk, 30 m/min, 7% grade for 5 wk) on the expression of myosinheavy chain (MHC) isoforms during and after regeneration of afast-twitch white muscle [extensor digitorum longus (EDL)]. Male Wistar rats were randomly assigned to a sedentary(n = 10) or an endurance-trained (ET;n = 10) group. EDL muscle degeneration and regeneration were induced by two subcutaneous injections of a snaketoxin. Five days after induction of muscle injury, animals were trainedover a 5-wk period. It was verified that ~40 days after venomtreatment, central nuclei were present in the treated EDL muscles fromsedentary and ET rats. The changes in the expression of MHCs in EDLmuscles were detected by using a combination of biochemical andimmunocytochemical approaches. Compared with contralateral nondegenerated muscles, relative concentrations of types I, IIa, andIIx MHC isoforms in ET rats were greater in regenerated EDL muscles(146%, P < 0.05; 76%,P < 0.01; 87%,P < 0.01, respectively). Their elevation corresponded to a decreasein the relative concentration of type IIb MHC (36%,P < 0.01). Although type I accountedfor only 3.2% of total myosin in regenerated muscles from the ETgroup, the cytochemical analysis showed that the proportion of positive staining with the slow MHC antibody was markedly greater in regenerated muscles than in contralateral ones. Collectively, these results demonstrate that the regenerated EDL muscle is sensitive to endurance training and suggest that the training-induced shift in MHC isoforms observed in these muscles resulted from an additive effect of regeneration and repeated exercise. 相似文献
995.
A. M. A. Nascimento H. R. T. Souza M. S. Xavier J. E. Thiemann L. Vilela M. Mares-Guia 《Biotechnology Techniques》1996,10(10):737-742
Summary A proinsulin analog constructed by site-directed mutagenesis was expressed as a fusion protein that formed inclusion bodies inside the cells. It was purified from the isolated inclusion bodies and proinsulin was obtained by trifluoro-acetic acid, dimethyl sulfoxide and hydrochloric acid cleavage. The released proinsulin analog was confirmed by its molecular weight as determined by SDS-PAGE. 相似文献
996.
Pilar Teixidor Miguel ángel Arráez Glòria Villalba Roser Garcia Manel Tardáguila Juan José González Jordi Rimbau Xavier Vidal Eva Montané 《PloS one》2016,11(2)
Background
During the last decade, the use of 5-aminolevulinic acid (5-ALA) has been steadily increasing in neurosurgery. The study''s main objectives were to prospectively evaluate the effectiveness and safety of 5-ALA when used in clinical practice setting on high-grade gliomas’ patients.Methods
National, multicenter and prospective observational study. Inclusion criteria: authorized conditions of use of 5-ALA. Exclusion criteria: contraindication to 5-ALA, inoperable or partial resected tumors, pregnancy and children. Epidemiological, clinical, laboratory, radiological, and safety data were collected. Effectiveness was assessed using complete resection of the tumor, and progression-free and overall survival probabilities.Results
Between May 2010 and September 2014, 85 patients treated with 5-ALA were included, and 77 were suitable for the effectiveness analysis. Complete resection was achieved in 41 patients (54%). Surgeons considered suboptimal the fluorescence of 5-ALA in 40% of the patients assessed. The median duration of follow-up was 12.3 months. The progression-free survival probability at 6 months was 58%. The median duration overall survival was 14.2 months. Progression tumor risk factors were grade of glioma, age and resection degree; and death risk factors were grade of glioma and gender. No severe adverse effects were reported. At one month after surgery, new or increased neurological morbidity was 6.5%. Hepatic enzymes were frequently increased within the first month after surgery; however, they subsequently normalized, and this was found to have no clinical significance.Conclusion
In clinical practice, the 5-ALA showed a good safety profile, but the benefits related to 5-ALA have not been yet clearly shown. The improved differentiation expected by fluorescence between normal and tumor cerebral tissue was suboptimal in a relevant number of patients; in addition, the expected higher degree of resection was lower than in clinical trials as well as incomplete resection was not identified as a prognostic factor risk for death. Because optimal fluorescence was correlated to higher complete resection rate, further research is needed to identify patients (or tumors) with more surgery benefits when using the 5-ALA. 相似文献997.
Cystic fibrosis in Finland: a molecular and genealogical study 总被引:4,自引:4,他引:0
Juha Kere Reijo Norio Erkki Savilahti Xavier Estivill Albert de la Chapelle 《Human genetics》1989,83(1):20-25
Summary The incidence of cystic fibrosis (CF) in Finland is one tenth that in other Caucasian populations. To study the genetics of CF in Finland, we used a combined molecular and genealogical approach. Out of the 20 Finnish families with a living CF patient, 19 were typed for eight closely linked restriction fragment length polymorphisms (RFLP) at the MET, D7S8, and D7S23 loci. The birthplaces of the parents and grandparents were traced using population registries. Allele and haplotype frequencies in Finland are similar to those of other European and North American populations, but are modified by sampling: two regional CF gene clusters, evidently the results of a founder effect, were identified. Generally, the gene was evenly distributed over the population, carrier frequency being estimated at approximately 1.3%. We conclude that CF in Finland is caused by the common Caucasian mutation(s), and that the low frequency of the gene can be explained by a negative sampling effect and genetic drift. 相似文献
998.
We have investigated 67 primers designed by Dr. J. Todd and co-workers to amplify microsatellites sequences in the mouse. We report on additional polymorphisms concerning seven laboratory inbred strains, complementary to those already published. We include the survey of three independently derived strains of Mus spretus: SPE/Pas, SEG/Pas and SPR/Smh. SPE/Pas and SEG/Pas are very close (3% polymorphism), whereas the third one, (SPR/Smh), is very different from the other two strains (33% polymorphism). Seventy-four to 84% of the microsatellites analyzed in this study are polymorphic between C57BL/6Pas and Mus spretus strains. By comparison, 36–46% are polymorphic between laboratory inbred strains involved in established sets of recombinant inbred strains. A strain derived from Mus musculus musculus (PWK/Pas) was found to be very different from both C57BL/6Pas (70% polymorphism) and SPE/Pas (82% polymorphism). These results emphasize the interest of using Mus musculus musculus inbred strains to establish interspecific crosses, particularly when considering their breeding performances. 相似文献
999.
Salvador Peris Anna Motis Albert Martinez-Vilalta und Xavier Ferrer 《Journal of Ornithology》1991,132(4):445-449
Summary We studied the wintering of European Starlings by means of ringing recoveries since 1960 and the distribution of roosting sites in the last fifty years. An overall decrease was found in the number of roosts as well as in wintering birds. However, this is due to a a considerable decrease in the south and east, whereas in the north and northeast the number of wintering birds seems to be stable ore even lightly increasing. This geographical difference can be correlated with the decline of breeding populations in North and Central Europa and/ore with the growing populations in France and Belgium respectively. In the last decade, the number of urban roosts in Spain increased. 相似文献
1000.
Tanymastix stagnalis is known from seven locations in Ireland. These range from small to large temporary water bodies. It was earlier shown that the best hatching and survival of eggs and young stages occurred in the presence of soil and at temperatures between about 10° and 15°. Some eggs hatched after one drying period, others after up to at least 4 drying and wetting periods. It was found from field observations that the habitat appeared after a minimum of 200 mm of rain in a 2-month period. This occurred on average more than once per year, mostly between June and February. A computer model was constructed using field data, and meteorological data (rainfall and temperature) covering 100 years, to decide how secure the organism was in two contrasting habitats. This showed that in both habitats there was little likelihood of extinction from metorological causes. There was, however, the possibility of destruction of the smaller habitats either through drainage or conversion to permanent ponds through compaction of the soil by heavy farm animals. The distribution and the possibility of harvesting the organisms is briefly discussed. 相似文献