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81.
As ectothermic animals, snakes depend exclusively on the environment for proper temperature maintenance, which may greatly influence their activity. Twenty-five adult Boa constrictor amarali snakes maintained in captivity were used to determine the influence of seasons on their hematologic values and electrophoretic profile of hemoglobin. A complete blood cell count (CBC) and examination for hemoparasites were performed in the summer and winter of 2004. Hemoglobin was stored for later electrophoresis. Significant differences (P < 0.05) were obtained in RBC, WBC, lymphocyte, thrombocyte, and monocyte counts, demonstrating the importance of the period of the year in the interpretation of reference values in these animals. Two snakes were detected with blood parasites (Hepatozoon sp.) in the winter and four in the summer, although it appears that their presence did not cause any significant alterations in the CBC. The electrophoretic analysis of the samples demonstrated two-four hemoglobin bands in this species.  相似文献   
82.
Immunohistochemistry was used to examine feline lymphoid tumors for bcl-2 and MIB-1 expression. Tumor tissues from 29 cats were selected to represent 2 groups--cats that did not respond to chemotherapy and cats that responded to therapy. Median bcl-2 immunoreactivity was 60%, and median MIB-1 reactivity was 47%. There was no significant difference in median survival time between cats with tumors with high levels of bcl-2 expression and those with low levels of expression. There was no significant difference in median survival time between cats with tumors with high levels of MIB-1 expression and those with low levels of expression. Mean bcl-2 immunoreactivity was significantly (P = .0004) higher in low-grade (73.2%) than in high-grade (16.9%) lymphomas, whereas the mean MIB-1 immunoreactivity was significantly (P = .0201) higher in high-grade (61.2%) lymphomas than in low-grade (35.0%) lymphomas. The mean bcl-2 immunoreactivity was significantly (P = .0042) greater in T-cell lymphomas (66.8%) than in B-cell lymphomas (22.8%), whereas the mean MIB-1 immunoreactivity was significantly (P = .0052) lower in T-cell lymphomas (36.4%) than in B-cell lymphomas (65.2%). Although expression of bcl-2 and MIB-1 did not appear to be linked to responses to chemotherapy in cats with lymphoma, the data suggest a possible role for these regulatory proteins in the biology of feline lymphomas.  相似文献   
83.
Background: The distribution and frequency of blood types in cat populations vary according to geographic region and breed. Frequencies of feline blood types in Rio de Janeiro city, as well as in other Brazilian areas, are unknown, and the risk of unmatched transfusions and neonatal isoerythrolysis has not been estimated. Objectives: The purpose of this study was to determine the frequency of feline blood types in the area of Rio de Janeiro, Brazil. Methods: EDTA blood samples were obtained from 172 nonpedigreed domestic shorthair (DSH) cats (92 female, 80 male, 3 months-20 years old) in different sites of Rio de Janeiro city. Blood typing was performed by agglutination assays using Triticum vulgaris lectin and feline anti-A serum. The hemagglutination results for type B and AB cats were confirmed by high-performance thin-layer chromatography (HPTLC) of erythrocyte membrane gangliosides. Results: The majority (163/172, 94.8%) of cats were type A, 2.9% were type B, and 2.3% were type AB. High-titer anti-A serum agglutinated RBCs from all cats in type A and type AB blood groups, with 3+ to 4+ agglutination. The probability that a type A cat would receive type B or AB blood in a first random transfusion was calculated as 2.25% and 2.20%, respectively. HPTLC analysis of glycolipids yielded a chromatographic profile characteristic of feline gangliosides for all blood groups. Conclusions: These results indicate a high prevalence of type A cats in Rio de Janeiro, Brazil, and a low frequency of type B and AB cats, consistent with what has been observed for DSH cats in other regions of the world.  相似文献   
84.
The high infraspecific chemical and morphological polymorphism is characteristic for species of genus thyme (Thymus L.). This characteristic can be subservient to the selection of valuable clones from natural habitats. The objective of the present study was to select valuable Thyme clones from native flora of Lithuania according to the productivity of biomass and chemical composition of essential oils for the cultivation. Two Thymus species, namely large thyme (T. pulegioides L.) and wild thyme (T. serpyllum L.), grow wild in Lithuania and other Baltic States (Latvia and Estonia). Was established that T. pulegioides is more suitable for the cultivation than T. serpyllum, because can grow more dried total biomass (up to 3 times), are higher (2.8 times) and synthesize higher amount of essential oils with significant amounts of such biologically active compounds as the thymol, carvacrol, geraniol or linalool. Four most fecund clones of T. pulegioides (the total biomass of dried plant 29–45 g, the amount of essential oil in whole plant 0.5–0.7%) were selected which accumulate the highest amounts of thymol (up to 26.1%), carvacrol (up to 31.0%), geraniol (up to 45.0%) and linalool (up to 80.3%). The cultivation of these clones enables to get the high yield of biomass and chemically homogeneous herbal raw material of desirable chemical composition for the phytomedicines and phytocosmetics.  相似文献   
85.
The aim of this paper is to discuss how community relational economic practices in virtual spaces are effective in building resilience because they are borne of and sustained by familiar traditional Fijian values of collective work and social interdependence. The researchers adopted a pandemic-induced methodology, conducting online-based talanoa (fluid conversations between two or more people) with a number of people leading, or involved in, these initiatives. We also engaged with online community groups behind a number of initiatives. Examples are provided of online crowdfunding, livestreaming of concerts to solicit donations, and bartering facilitated by social media sites. To conclude, we stress the enduring nature of communal bonds and traditional systems which Pacific people readily adapt and translate into different forums and forms in the face of challenges such as the restrictions and financial hardships caused by COVID-19. The findings highlight that solesolevaki – a tradition of working together for a common cause – can also occur in the digital era: this demonstrates the deep connection of Fijian peoples and their sense of obligation to one another and to their culture, regardless of where they are in the world.  相似文献   
86.
Sulfated polysaccharides (SPS) from seaweeds have great biochemical and biotechnological potential. This study aimed to investigate the effect of SPS isolated from the seaweed Caulerpa sertularioides on adipogenic differentiation as a possible alternative treatment for obesity. The SPS-rich extract from the seaweed C. sertularioides was fractioned into three SPS-rich fractions (F0.5; F0.9; and F1.8) chemically characterized. Among these four samples, only F0.9 showed a significant inhibitory effect on adipogenesis of 3T3-L1 preadipocytes. Ten SPS-rich fractions were isolated from F0.9 through ion-exchange chromatography. However, only the fraction (CS0.2) containing a sulfated glucan was able to inhibit adipogenesis. CS0.2 reduces lipid accumulation and inhibits the expression of key adipogenic (PPARγ, C/EBPβ, and C/EBPα) and lipogenic markers (SREBP-1c, Fabp4, and CD36). The data points to the potential of sulfated glucan from C. sertularioides for the development of functional approaches in obesity management.  相似文献   
87.
Seaweed production represents one of the rising activities in the aquaculture industry. This study explores the impact of bacteria associated with the growth of Ulva clathrata, a promising alga in the field of food and bioremediation. Fifty‐six bacteria isolated from four seaweed (Caulerpa sp., Gracilaria sp., Ulva lactuca and U. clathrata) were tested to evaluate their effect on U. clathrata growth. Eight of them showed a significant growth‐promoting effect (p < .05). Isolates Ul‐11 and Ul‐12 from U. lactuca induced an increase of 73 and 81% of growth respectively. They were classified as Reugeria sp. and Alteromonas sp. based on 16S DNA sequencing (>95.0% sequence identity). Multiple combinations of the growth‐promoting bacteria were also tested on U. clathrata, and the best result was achieved by combining Ca‐3/Uc‐18/Ul‐12 isolates with a significant increase in seaweed growth of up to 76%; however, no synergistic effect was observed compared to Ul‐12 alone. Scanning electron microscopy revealed no alteration in the cell wall of U. clathrata when inoculated with selected bacteria, showing an average increase of bacterial density on U. clathrata.  相似文献   
88.
BACKGROUND: Infection with Ehrlichia canis causes a highly variable, multisystemic disease in dogs. Nevertheless, many clinicians in Rio de Janeiro, Brazil, use the presence of only thrombocytopenia to make a presumptive diagnosis of E canis infection. OBJECTIVE: The objective of this study was to determine the prevalence of E canis in thrombocytopenic dogs from Rio de Janeiro, Brazil, using polymerase chain reaction (PCR). METHODS: Following DNA extraction of whole blood samples from 226 dogs, PCR assays were done using primers for rickettsial DNA (including Ehrlichia spp, Anaplasma platys and A phagocytophilum) and using E canis-specific primers (16S rRNA gene). Dogs were grouped as thrombocytopenic and nonthrombocytopenic based on platelet counts. The null hypothesis that there was no difference in the prevalence of E canis in these groups was rejected at P<.05. RESULTS: Thirty-six (32.1%) of the thrombocytopenic dogs and 4 (3.5%) of the nonthrombocytopenic dogs were positive for rickettsial gene sequences (P<.0001). Further, 30 (26.8%) of thrombocytopenic dogs and 4 (3.5%) nonthrombocytopenic dogs were positive for E canis-specific gene sequences (P<.0001). CONCLUSIONS: Although the prevalence of E canis infection was higher in thrombocytopenic dogs, less than one third of these dogs had demonstrable E canis infection. Thus, thrombocytopenia is not specific for the detection of E canis infection and should not be used solely to establish a diagnosis of canine ehrlichiosis, even in a geographic area with relatively high disease prevalence.  相似文献   
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