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31.
The synthesis and secretion of trypsin (trypsin model serine protease) inhibitors are regulated in ovarian follicles by gonadotropins. The superovulation stimulations with 400 IU FSH, 1000 IU PMSG, 1000 IU HCG, 750 IIU PMSG + 750 IU HCG influence in a different way the trypsin inhibiting activities (TIA) of blood plasma (BP) (Figs 1 and 2) and follicular fluid (fig. 3); this points to a possibility of local effects. An increase in the average values of TIA in BP was statistically significant during the whole experiment: P less than 0.05 to P less than 0.001 (following the administration of PMSG+HCG, or PMSG, and HCG); Antisergon administered in 68 hours after PMSG reduced this increase. The changes in the fraction of low-molecular TIA in BP (after BP treatment with perchloric acid) were of converse nature; a decrease in the average values ranged from P less than 0.02 to P less than 0.001 (following PMSG or other stimulations). Antisergon did not influence this decrease. The changes observed on particular days of the trial (Figs. 1 and 2) also indicate different effects of the preparations, mainly of the component LH, which resulted in the occurrence of large nonovulating follicles (greater than 10 mm--"cystic" ones). No such follicles were observed in nonstimulated ewes and after FSH stimulation. The administration of antisergon (goat's antiserum against PMSG) 68 hours after PMSG administration did not prevent their creation. The TIA of follicular fluid (FF) of antral follicles was on average tenfold in comparison with that of blood plasma; and the TIA FF of follicles greater than 10 mm was higher (up to P less than 0.001) than the TIA FF of follicles less than 10 mm. The administration of Antisergon in shorter intervals following PMSG administration (12, 24, 48 and 58 hours) influenced the average values of TIA BP in 120 hours (since PMSG administration) in dependence on time (Tab. I). The effects of Antisergon administered in 12 and 24 hours after PMSG administration on the TIA BP were insignificant if it was administered in 48 and 58 hours the TIA BP increased (P less than 0.02; P less than 0.001) in comparison with the interval of 12 hours. The TIA FF of follicles less than 5 mm, 5-10 mm and greater than 10 mm varied in dependence on the time intervals of Antisergon administration (Fig. 4). The statistical significance of these changes in shown in Tab. II.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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Four infectious agents were isolated from the ticks Ixodes ricinus (L.) collected in the recreational area and park-forest of Prague. On the basis of cultivation, staining, biochemical, serologic properties, pathogenicity for animals and histological tests they were identified as Francisella tularensis with the following features: they are short, gram-negative rods of approximate dimensions of 0.3 X 0.8 micron, growing in enriched media after 3-4 day incubation at 37 degrees C. They form small circular, at first transparent, later greyish turbid colonies with regular rims. They are little active biochemically. They are susceptible to streptomycin and some broad spectrum antibiotics. They react positively with tularemic serum, but in lower titres than those in which this serum reacts with standard antigen. The microbes are highly pathogenic for mice, guinea-pigs, young rats, in which a massive bacteriemia occurs before death, but they do not kill rabbits. They multiply well in chick embryo, but do not grow in cell or tissue cultures. The most important histologic changes were observed in liver and spleen of mice. No pathologic changes were found in brain, lungs, heart, kidneys. Necroses were found in liver and in their marginal zones the microbes were present. Conspicuous were changes in numerous hepatocytes which became enlarged due to microbial multiplication and finally transformed into "sacs" packed with microbes. Histological and electronoptical examination showed that these are intracellular parasites fringed with a light lytic zone. Discussed is the problem to what extent the properties of the isolated strains are typical of F. tularensis as well as the importance of their detection from the aspect of epidemiology and differential diagnostics.  相似文献   
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A moth egg assignable to the family Noctuidae (Lepidoptera) is described from 75-million-year-old sediments from Martha's Vineyard, Massachusetts. This sample, which extends the fossil record of this farnily and modern heteroneuran moths back to the Cretaceous, may provide insight into the coevolution of moths and flowering plants, as well as have implications for the evolution of bats.  相似文献   
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A novel concept for performing stoichiometric and catalytic chemical transformations has been developed that is based on the limited miscibility of partially or fully fluorinated compounds with nonfluorinated compounds. A fluorous biphase system (FBS) consists of a fluorous phase containing a dissolved reagent or catalyst and another phase, which could be any common organic or nonorganic solvent with limited or no solubility in the fluorous phase. The fluorous phase is defined as the fluorocarbon (mostly perfluorinated alkanes, ethers, and tertiary amines)-rich phase of a biphase system. An FBS compatible reagent or catalyst contains enough fluorous moieties that it will be soluble only or preferentially in the fluorous phase. The most effective fluorous moieties are linear or branched perfluoroalkyl chains with high carbon number; they may also contain heteroatoms. The chemical transformation may occur either in the fluorous phase or at the interface of the two phases. The application of FBS has been demonstrated for the extraction of rhodium from toluene and for the hydroformylation of olefins. The ability to separate a catalyst or a reagent from the products completely at mild conditions could lead to industrial application of homogeneous catalysts or reagents and to the development of more environmentally benign processes.  相似文献   
36.
SUMMARY: Thirteen biochemical blood polymorphisms were analysed in a population of 149 Spanish Avile?a-Negra Ibérica cattle. The study revealed variation at the following nine loci: HBB, CA, NP, CP, AMY1, ALB, GC, TF and PTF2. The following systems were monomorphic: CAT, DIA1, MDH1 and ME1. Using polyacrylamide-gel electrophoresis, a slow, migrating pair of bands was found in the GC protein system. This pattern is probably controlled by the GC(C) allele, described in only a few cases in cattle. Furthermore, starch-gel electrophoresis allowed the detection of a variant with intermediate mobility between the ALB(A) and the ALB(B) alleles at the albumin locus. A variant with a similar electrophoretic pattern has occasionally been reported in cattle. However, utilizing IEF under denaturing conditions, such a variant could not be differentiated from the ALB(A) allele and thus its significance is not clear. ZUSAMMENFASSUNG: Biochemischer Polymorphismus in spanischen Avile?a-Negra Iberica Rindern Insgesamt 13 biochemische Systeme wurden in einer Population von 149 spanischen Avilena-Negra-Iberika-Rindern hinsichtlich Polymorphismus analysiert. Es zeigten sich Varianten bei folgenden Loci: HBB, CA, NP, CP, AMY1, ANB, GC, TF und BTF2, w?hrend CAT, DEA, MDH1 und ME1 monomorph sind. Bei st?rke Gel-Elektrophorese wurde im Albumin-Locus eine Variante mit intermedi?rer Mobilit?t zwischen ALB(A) und ?LB(B) Allel entdeckt. Eine solche Variante wurde bisher nur sehr selten bei Rindern beobachtet. Darüber hinaus wurde bei Polyacrylamid-Gel-Elektrophorese ein langsam wanderndes Paar von B?ndern im GC-Proteinsystem gefunden. Dieses Muster ist wahrscheinlich von dem selten vorkommenden GC(C) -Allel verursacht. RESUMEN: Se analizaron trece polimorfismos bioquímicos sanguíneos en una población de 149 animales de la raza Avile?a-Negra Ibérica de ganado vacuno. El estudio reveló la existencia de variación en los nueve loci siguientes: HBB, CA, NP, CP, AMY1, ALB, GC, TF y PTF2. Fueron monomórficos los sistemas siguientes: CAT, DIA1, MDH1 y ME1. Utilizando eletroforesis en gel de poliacrilamida se encontró un par de bandas de migración lenta en el sistema de la proteína GC. Este patrón probablemente está controlado por el infrecuente alelo GC(C) , descrito en unos pocos casos en el ganado vacuno. Además, la electroforesis en gel de almidón permitió detectar en el locus de la albúmina una banda con movilidad intermedia entre los alelos ALB(A) y ALB(B) . Una variante con un patrón electroforético similar ha sido descrita en muy pocas ocasiones en el ganado vacuno. Sin embargo, la utilización de IEF en condiciones desnaturalizantes no permitió diferenciar esta variante del alelo ALB(A) y, por lo tanto, el significado de la misma no está claro.  相似文献   
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The cercariae of Eurytrema pancreaticum (Janson, 1889) possess four types of gland cells - proper cystogenic, penetration, ventral and dorsal gland cells. The secretion of ventral and dorsal gland cells is released into the tegument. The proper cystogenic gland cells are the largest and their contents serve for the formation of the cyst wall of metacercariae in the second intermediate host. The secretion of proper cystogenic gland cells contains besides neutral mucosubstances also acid mucosubstances with both carboxyl- and sulphogroups digestible with beta-glucuronidase. The secretion of penetration gland cells contains neutral mucosubstances and proteins with tyrosine, tryptophan and SS groups. The ventral gland cells contain mostly acid mucosubstances with sulphogroups, which are digested with beta-glucuronidase, and proteins with tyrosine, tryptophan and SH groups. The rudimentary dorsal gland cells contain a small amount of acid mucosubstances. The whole tegument of cercariae and the two main collecting canals of the excretory system exhibit a high alkaline phosphatase activity. The nerve ring and the main nerve truncs contain proteins with SH groups and hydrophilic lipids and exhibit a cholinesterase activity. The suckers contain a larger amount of glycogen.  相似文献   
40.
The tissue reaction to Cysticercus bovis in the lung of cattle with an experimental infection was an inflammatory rim originating in the immediate vicinity of the cysts. The cysts recovered at days 83 and 102 p.i. contained living cysticerci. The rim was composed either of a layer of high histiocytes organized in palisades (at day 83 p.i.), or a lyer of flat histiocytes (at day 102 p.i.). The outer layer of the rim consisted of fibroblasts, reticular cells and a different number of eosinophil- and neutrophil luekocytes. On the periphery, the rim was formed by granulation tissue infiltrated with lymphoplasmocytes. At the border between the layers of the inflammatory rim there were conspicuous foci of a necrotic appearance typical of a tissue reaction to C. bovis.  相似文献   
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