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1.
Representatives of the genus Proterorhinus (tubenose gobies) from the water bodies of the Ponto-Caspian Basin were examined for sequence polymorphism of the mitochondrial DNA fragment containing the cytochrome b (Cyt-b) gene. A total of ten haplotypes were discovered, which formed two groups. Thus, the data obtained indicated the existence of only two taxonomically valid phylogenetic lineages, represented by (1) marine and brackish-water populations of the Black Sea and (2) freshwater populations of the whole Ponto-Caspian Basin, along with the brackish-water population of the Caspian Sea. Based on an analysis of the tubenose goby haplotype distribution patterns, the colonization patterns of this group of fishes (phylogeography) in the freshwater drainages of Ponto-Caspian Basin are examined. It was established that the basin of the ancient Caspian Sea was the major donor area for the formation of the freshwater and brackish-water populations. In the Ponto-Caspian Basin, two centers of the tubenose gobies speciation and distribution are distinguished. One of these centers is associated with the modern northwestern part of the Black Sea, and another one is confined to the Caspian Sea. It is suggested that the modern colonization of the Volga River by tubenose goby occurred from the Caspian Sea.  相似文献   
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Coregonus peled (Gmelin) (Teleostei: Salmoniformes: Coregonidae), which is considered an important object of coldwater aquaculture, had been successfully introduced into an enclosed Western Mongolian lake Ulaagchny Khar in the early 1980s. At the same time larvae of two other Coregonus species—Baikal omul C. migratorius (Georgi) and least cisco C. sardinella Valenciennes—had also been released into the lake. Baikal omul was then reported as a naturalized species. This might have caused interspecific hybridization and gene introgression. Identification of coregonids by morphology can be problematic, so to determine which species was dominant in the lake (we presumed it was peled) and if its gene pool was affected by other introduced Coregonus species we sampled 40 individuals and analyzed them by sequencing a fragment of mtDNA cyt b and by allozyme electrophoresis. The analysis showed that all the fish belonged to C. peled with no evidence of admixture from other coregonid species. Taking into account mass release of both species in 1980s, it is evident that naturalization of peled in the lake was much more successful than that of Baikal omul.  相似文献   
3.
We describe a female patient aged 43, who at the age of five was diagnosed with polyostotic fibrous dysplasia (FD). The patient was intermittently treated in our department since the age 33, for approximately 10 years, with intravenous bisphosphonates. At the age of 42 acromegaly was diagnosed incidentally, since clinical manifestations were poor, and, if present earlier, they had been related to FD. Only retrospectively, having biochemical confirmation of GH excess, we could relate them to acromegaly. Because of the involvement of the base of the skull there was no possibility of transphenoidal surgery. Long-acting somatostatin analogues were started, but no response was observed, with IGF-1 and GH being even higher during than before treatment. After the 37-year-history of FD, the occurrence of additional endocrine disorder enabled to make diagnosis of McCune-Albright syndrome (MAS) even in the absence of two out of three classical manifestations such as café-au-lait skin pigmentation and peripheral precocious puberty in the past medical history.  相似文献   
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Background

Avoidance of allergens is still recommended as the first and best way to prevent allergic illnesses and their comorbid diseases. Despite a variety of attempts there has been very limited success in the area of environmental control of allergic disease. Our objective was to identify a non-invasive, non-pharmacological method to reduce indoor allergen loads in atopic persons' homes and public environments. We employed a novel in vivo approach to examine the possibility of using aluminum sulfate to control environmental allergens.

Methods

Fifty skin test reactive patients were simultaneously skin tested with conventional test materials and the actions of the protein/glycoprotein modifier, aluminum sulfate. Common allergens, dog, cat, dust mite, Alternaria, and cockroach were used in the study.

Results

Skin test reactivity was significantly reduced by the modifier aluminum sulfate. Our studies demonstrate that the effects of histamine were not affected by the presence of aluminum sulfate. In fact, skin test reactivity was reduced independent of whether aluminum sulfate was present in the allergen test material or removed prior to testing, indicating that the allergens had in some way been inactivated.

Conclusion

Aluminum sulfate was found to reduce the in vivo allergic reaction cascade induced by skin testing with common allergens. The exact mechanism is not clear but appears to involve the alteration of IgE-binding epitopes on the allergen. Our results indicate that it may be possible to diminish the allergenicity of an environment by application of the active agent aluminum sulfate, thus producing environmental control without complete removal of the allergen.  相似文献   
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2,4,6-Triphenyldioxane-1,3 (TPD) is a highly effective species-specific inducer of CYP2В in rats. Several analogs of TPD were synthesized to verify a hypothesis that minor changes in the inducer structure can cause changes in induction abilities (R = H, cisTPD and transTPD; R = N(CH3)2, transpDMA; R = NO2, transpNO2; R = F, transpF; R = OCH3, transpMeO). Five of six compounds were able to activate CAR in rat liver. Results of Western-blot and ChIP showed that cisTPD and transTPD, transpDMA, transpNO2, transpF treatment stimulated nuclear accumulation of CAR and evoked CAR receptor PBREM-binding activity in rat liver. cisTPD, transTPD, transpDMA, transpNO2 and transpF administration significantly increased total CYP content (1.3–2.5 fold) and the level of PROD (12–20 fold), CYP2B specific activity, whereas transpMeO did not have any effects. Western blot and real-time RT-PCR showed that the increase of PROD in liver is related to the high content of CYP2B proteins and paralleled the increase of CYP2B1 (10–43 fold) and CYP2B2 (8–26 fold) mRNAs. At the same time content of CYP2B proteins and CYP2B1 and CYP2B2 mRNA levels were unchanged in rat liver after transpMeO treatment. The dose–response studies have shown that cisTPD, transpDMA, transpF and transpNO2 have similar potency, and transTPD is less potent derivative. Moreover, it is likely transTPD act as a partial CAR activator. Thus, our results provide evidence to support the conclusion that the differences of TPD analogs ability to activate CYP2B gene expression can be explained by various interactions with CAR.  相似文献   
9.
Bone tissue has an exceptional quality to regenerate to native tissue in response to injury. However, the fracture repair process requires mechanical stability or a viable biological microenvironment or both to ensure successful healing to native tissue. An improved understanding of the molecular and cellular events that occur during bone repair and remodeling has led to the development of biologic agents that can augment the biological microenvironment and enhance bone repair. Orthobiologics, including stem cells, osteoinductive growth factors, osteoconductive matrices, and anabolic agents, are available clinically for accelerating fracture repair and treatment of compromised bone repair situations like delayed unions and nonunions. Preclinical and clinical studies using biologic agents like recombinant bone morphogenetic proteins have demonstrated an efficacy similar or better than that of autologous bone graft in acute fracture healing. A lack of standardized outcome measures for comparison of biologic agents in clinical fracture repair trials, frequent off-label use, and a limited understanding of the biological activity of these agents at the bone repair site have limited their efficacy in clinical applications.  相似文献   
10.
The polymerase chain reaction with arbitrary primers (RAPD–PCR) was used to study and to evaluate the genetic variation in the hybrid progeny of two Cyprinidae species, common bream Abramis brama L. and roach Rutilus rutilusL. Genetic polymorphism was studied in 20 fishes (young of the current year) obtained in four individual crosses: R. rutilus × R. rutilus (RR), A. brama × A. brama (AA), R. rutilus × A. brama (RA), and A. brama × R. rutilus (AR). Amplification spectra obtained with eight primers contained 288 fragments, 97.6% of which proved to be polymorphic. The proportion of polymorphic fragments was 75.0% in the RR progeny, 58.1% in the AA progeny, 84.9% in the AR progeny, and 77.8% in the RA progeny. Classification analysis in the space of principal components was performed with the first four components, which together accounted for 64% of the total variance of the character under study. The individual contributions of components I, II, III, and IV were 26.8, 16.8, 11.5, and 8.9%, respectively. Fishes of the two pure species and the hybrid progeny (direct and reverse hybrids together) were clearly differentiated in the space of principal components I and II. The best differentiation of the four samples (RR, AA, RA, and AR) was observed in the space of principal components II and IV. Possible causes of high genetic variation in interspecific hybrids are discussed.  相似文献   
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