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91.
92.
The contents obtained by fine needle aspiration (FNA) from 41 pancreatic cysts in 32 patients were studied cytologically and assayed for amylase and carcinoembryonic antigen (CEA) levels, which have been shown to discriminate pancreatic pseudocysts from mucinous cystic neoplasms and necrotic cystic carcinomas. The results were correlated with the histopathologic findings following surgery or with a clinical and radiologic follow-up of up to two years. The clinical, radiologic and cytologic characteristics did not discriminate pseudocysts from cystic neoplasms. The amylase content of cysts was high in pseudocysts, cystic carcinomas and mucinous cystic neoplasms. The mean CEA content was highest in cystic carcinomas and mucinous cysts and low in pseudocysts. The cytologic diagnosis of mucinous cystic neoplasms and carcinomas had a sensitivity of 54% and a specificity of 91%. The diagnosis of these lesions based on a CEA level greater than 10 ng/ml had a sensitivity of 100% and a specificity of 81%. The adjunctive use of CEA content analysis enhanced the sensitivity of the cytologic diagnosis of mucinous cystic neoplasms and carcinomas to 100%.  相似文献   
93.
This paper describes sand flies similar to Nyssomyia intermedia (Lutz & Neiva) with variations in the number of spines at the gonostyle and tests the hypothesis whether these specimens belong or not to N. intermedia species. Using Principal Component Analysis and Neighbour Joining, the measurements of 15 structures of the phlebotomine with variations in number of spines were compared with measurements of 30 sand flies of N. intermedia species. Both analyses didn't cluster the specimens with variation in spines number in one group and provided evidence to the hypothesis that those sand flies belong to N. intermedia.  相似文献   
94.
The activity of a sarcosine dehydrogenase isolated from a strain of Pseudomonas is enhanced by the addition of Triton X-100, Brij 35, and Tween 80, and is inhibited by deoxycholate and Sarkosyl NL-97. 2,6-Dichlorophenolindophenol, which is used as the oxidant in the dehydrogenase assay, has also been employed as an indicator in the spectrophotometric determination of the critical micelle concentrations (CMC) of both the nonionic and anionic detergents under conditions optimal for the enzyme analyses. A correlation between the activation or inhibitory activities of the surfactants and their CMC values has been established.  相似文献   
95.
A new galactose-specific lectin was purified from seeds of a Caesalpinoideae plant, Bauhinia variegata, by affinity chromatography on lactose-agarose. Protein extracts haemagglutinated rabbit and human erythrocytes (native and treated with proteolytic enzymes), showing preference for rabbit blood treated with papain and trypsin. Among various carbohydrates tested, the lectin was best inhibited by D-galactose and its derivatives, especially lactose. SDS-PAGE showed that the lectin, named BVL, has a pattern similar to other lectins isolated from the same genus, Bauhinia purpurea agglutinin (BPA). The molecular mass of BVL subunit is 32 871 Da, determined by MALDI-TOF spectrometry. DNA extracted from B. variegata young leaves and primers designed according to the B. purpurea lectin were used to generate specific fragments which were cloned and sequenced, revealing two distinct isoforms. The bvl gene sequence comprised an open reading frame of 876 base pairs which encodes a protein of 291 amino acids. The protein carried a putative signal peptide. The mature protein was predicted to have 263 amino acid residues and 28 963 Da in size.  相似文献   
96.
Accurate contextual decision-making strategies are important in social environments. Specific areas in the brain are tasked to process these complex interactions and generate correct follow-up responses. The dorsolateral and dorsomedial parts of the telencephalon in the teleost fish brain are neural substrates modulated by the neurotransmitter dopamine (DA), and are part of an important neural circuitry that drives animal behaviour from the most basic actions such as learning to search for food, to properly choosing partners and managing decisions based on context. The Indo-Pacific cleaner wrasse Labroides dimidiatus is a highly social teleost fish species with a complex network of interactions with its ‘client’ reef fish. We asked if changes in DA signalling would affect individual learning ability by presenting cleaner fish two ecologically different tasks that simulated a natural situation requiring accurate decision-making. We demonstrate that there is an involvement of the DA system and D1 receptor pathways on cleaners'' natural abilities to learn both tasks. Our results add significantly to the growing literature on the physiological mechanisms that underlie and facilitate the expression of cooperative abilities.  相似文献   
97.
Inhibitors targeting pancreatic alpha-amylase and intestinal alpha-glucosidases delay glucose production following digestion and are currently used in the treatment of Type II diabetes. Maltase-glucoamylase (MGA), a family 31 glycoside hydrolase, is an alpha-glucosidase anchored in the membrane of small intestinal epithelial cells responsible for the final step of mammalian starch digestion leading to the release of glucose. This paper reports the production and purification of active human recombinant MGA amino terminal catalytic domain (MGAnt) from two different eukaryotic cell culture systems. MGAnt overexpressed in Drosophila cells was of quality and quantity suitable for kinetic and inhibition studies as well as future structural studies. Inhibition of MGAnt was tested with a group of prospective alpha-glucosidase inhibitors modeled after salacinol, a naturally occurring alpha-glucosidase inhibitor, and acarbose, a currently prescribed antidiabetic agent. Four synthetic inhibitors that bind and inhibit MGAnt activity better than acarbose, and at comparable levels to salacinol, were found. The inhibitors are derivatives of salacinol that contain either a selenium atom in place of sulfur in the five-membered ring, or a longer polyhydroxylated, sulfated chain than salacinol. Six-membered ring derivatives of salacinol and compounds modeled after miglitol were much less effective as MGAnt inhibitors. These results provide information on the inhibitory profile of MGAnt that will guide the development of new compounds having antidiabetic activity.  相似文献   
98.
Serum samples from 18 pumas (Puma concolor), one ocelot (Leopardus pardalis), and two little spotted cats (Leopardus tigrinus) collected from free-ranging animals in Brazil between 1998 and 2004 were tested by indirect immunofluorescence (IFA) for antibodies to feline herpesvirus 1 (FHV 1), calicivirus (FCV), coronavirus (FCoV), parvo-virus (FPV), Ehrlichia canis, Anaplasma pha-gocytophilum, and Bartonella henselae. Serum samples also were tested, by Western blot and ELISA, for feline leukemia virus (FeLV) specific antibodies and antigen, respectively, by Western blot for antibodies to feline immunodeficiency virus (FIV), and by indirect ELISA for antibodies to puma lentivirus (PLV). Antibodies to FHV 1, FCV, FCoV, FPV, FeLV, FIV, PLV or related viruses, and to B. henselae were detected. Furthermore, high-titered antibodies to E. canis or a closely related agent were detected in a puma for the first time.  相似文献   
99.
Fine-needle aspiration cytology (FNAC) is essential for making a diagnosis in advanced breast cancer. The determination of hormone receptors in the material obtained is useful for predicting patient response to endocrine therapy, but the prognostic value of hormone receptor expression as well as the clinical utility of DNA flow cytometry are controversial. The aim of this prospective study with long-term follow-up (median: 81 months) was to evaluate these biomarkers in relation to overall survival in a series of 392 patients with advanced breast cancer (stage IIB, n=106; IIIA, n=66; IIIB, n=174; and IV, n=46) using FNAC. Estrogen and progesterone receptor expression was found in 65.1% and 46.1% of the tumors, respectively. Hormone receptors were not found to be associated with clinical staging. DNA aneuploidy was present in 70.9% of the cases and the median S-phase fraction (SPF) was 9.4%. There was a significant correlation of aneuploidy and high SPF with lack of hormone receptors. In univariate analysis, advanced disease stage, absence of hormone receptors, DNA aneuploidy and high SPF showed a statistically significant correlation with poor clinical outcome. In multivariate analysis, disease stage, progesterone receptors and DNA ploidy retained independent prognostic significance in relation to overall survival. These data indicate that progesterone receptor expression and DNA ploidy are independent prognostic factors in advanced breast cancer.  相似文献   
100.
This study investigated the major soluble antigens produced by Paracoccidioides brasiliensis (Pb339) cultured in solid Sabouraud (pH 5.6 and 8.5), Sabouraud plus brain heart infusion and liquid tomato juice‐enriched complex medium media at intervals of 3 days over 30 days by immunoblotting and concluded that, to optimize the source of each antigen, both time and growth conditions should be considered.  相似文献   
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