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41.
Vibrio cholerae O1 in plankton samples collected from ponds and rivers between February 1987 and January 1990 in Matlab, Bangladesh, was detected by the fluorescent-monoclonal antibody (FA) technique. Samples were collected at sites which were monitored fortnightly (fixed sites) as well as at sites that were part of a case-control study. FA results were compared with those obtained by conventional culture methods (CM). A total of 876 samples were collected; V. cholerae O1 was detected in 563 samples (64.27%) by the FA method and in 3 samples (0.34%) by CM. Of the fixed-site plankton samples, 439 (63.62%) were positive by FA and none were positive by CM. Of the 93 case sites sampled on the day after the occurrence of a case of cholera, 73 (78.49%) were positive for V. cholerae O1 by FA and 3 (3.2%) were positive by CM. In comparison, of the 93 first-day sample collections at control sites at the time a case of cholera occurred, only 51 (54.83%) were positive by FA and none were positive by CM. From the data, it is concluded that V. cholerae O1 is present throughout the year in the ponds and rivers of Bangladesh that were examined in this study and that V. cholerae can be detected by FA but not always by CM. The FA procedure was found to be very useful in detecting V. cholerae in plankton, with which it was associated and often occurred in large numbers in the nonculturable stage. Thus, studies investigating the significance of the role of environmental factors in the epidemiology of cholera can be performed effectively by using FA. Such studies are in progress.  相似文献   
42.
Bovine gastric mucosal and muscle microsomes synthesize prostaglandins and thromboxane B2 (TXB2) from arachidonic acid (AA). TXB2 and 6-keto-prostaglandin F1α (6-keto-PGF1α) were the major products synthesized by pylorus, body, and cardiac region of the gastric mucosa. Gastric muscle mainly synthesized 6-keto-PGF1α. TXB2 and 6-keto-PGF1α synthesis occurs at an appreciable rate from endogenous precursors but more rapidly with added arachidonate. Prostaglandins E2, F2α and D2 were synthesized in smaller amounts under the conditions studied.  相似文献   
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Synopsis The histochemical localization of carbohydrates, ribonucleoproteins (RNA), lipids, some hydrolytic enzymes, succinate and lactate dehydrogenase and acetylcholinesterase were investigated in the prostate, urethral and bulbourethral glands of the camel. These glands probably secrete carbohydrate-protein complexes. In the bulbourethral glands, they are sulphated mucopolysaccharides. RNA was seen in the cytoplasm of the prostate and urethral glands. Neutral lipids were cytoplasmic and present in moderate amounts in the prostate and urethral glands and in traces, in the bulbourethral gland. Acid phosphatase-containing granules were abundant in the prostate, moderate in the urethral glands and in traces in the bulbourethral glands. Alkaline phosphatase was observed in the apical cytoplasm of the prostate and bulbourethral glands and in the ducts of the urethral glands. ATPase and adenosine 5-monophosphatase were seen in the basal laminae and interstitial tissue. In the urethral glands, adenosine 5-monophosphatase was distributed diffusely in the cytoplasm. Succinate dehydrogenase was seen in the urethral and bulbourethral glands. Varying degrees of lactate dehydrogenase activity was observed in all the glands. Acetylcholinesterase was confined to neural elements. The pars disseminata and the urethral glands were considered as two distinct glandular zones along the pelvic urethra. The significance of these histochemical results is discussed.  相似文献   
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Papiha  S. S.  Roberts  D. F.  Ali  S. G. M.  Islam  M. M. 《Human genetics》1975,29(4):285-290
Human Genetics - In a sample of Bengali Muslems from Dacca, haptoglobin, group-specific component, haemoglobin, adenosine deaminase, adenylate kinase, 6-phosphogluconate dehydrogenase,...  相似文献   
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Eutherian Totipotent Cell Homeobox (ETCHbox) genes are mammalian-specific PRD-class homeobox genes with conserved expression in the preimplantation embryo but fast-evolving and highly divergent sequences. Here, we exploit an ectopic expression approach to examine the role of bovine ETCHbox genes and show that ARGFX and LEUTX homeodomain proteins upregulate genes normally expressed in the blastocyst; the identities of the regulated genes suggest that, in vivo, the ETCHbox genes play a role in coordinating the physical formation of the blastocyst structure. Both genes also downregulate genes expressed earlier during development and genes associated with an undifferentiated cell state, possibly via the JAK/STAT pathway. We find evidence that bovine ARGFX and LEUTX have overlapping functions, in contrast to their antagonistic roles in humans. Finally, we characterize a mutant bovine ARGFX allele which eliminates the homeodomain and show that homozygous mutants are viable. These data support the hypothesis of functional overlap between ETCHbox genes within a species, roles for ETCHbox genes in blastocyst formation and the change of their functions over evolutionary time.  相似文献   
49.
Background:Prostate cancer is known as one of the most prevalent health disorders in the male population globally. The aim of the current study was to evaluate the effects of separate and concomitant use of MK-2206 and salinomycin on prostate cancer cell line.Methods:The antitumor potential of separate and concomitant use of MK-2206 and salinomycin was evaluated in a panel of prostate cancer cell line (PC-3). To get insights into the underlying mechanism of action, different assays including the rate of apoptosis, cell viability, and gene expression were performed in treated prostate cancer cells.Results:A significant reduction was detected in the viability percentage of prostate cancer cells (p< 0.001) and the rate of Akt expression (p< 0.001) in all salinomycin, MK-2206, and salinomycin+MK-2206 groups compared to the negative control group. Furthermore, in comparison with the negative control group, there was a notable increase in both the rate of Bad expression (p< 0.001) and prostate cancer cells apoptosis after salinomycin, MK-2206, and salinomycin+MK-2206 treatments. Moreover, the concomitant use of salinomycin+MK-2206 revealed synergistic improvements regarding the viability of prostate cancer cells and the rate of the Akt and Bad expressions compared to the separate administration of salinomycin and MK-2206 (all p< 0.05)Conclusion:The findings of the present study may contribute to improving the efficacy of the therapies regarding the management of prostate cancer and providing a beneficial strategy in clinical trials.Key Words: Apoptosis, Gene Expression, MK 2206, Prostatic Neoplasms, Salinomycin  相似文献   
50.
Detection of Nitrosomonas spp. by polymerase chain reaction   总被引:2,自引:0,他引:2  
Abstract A unique genomic DNA fragment was isolated from Nitrosomonas europaea ATCC 19718. Based on the sequence of this fragment, oligonucleotide primers for polymerase chain reaction amplification were prepared which amplify sequences of 775 and 658 bp. The predicted DNA fragments were both amplified from the genome of N. europaea and a Nitrosomonas spp. isolated from a local oxidation pond. The primers failed to amplify DNA from the genomes of the ammonia oxidiser Nitrosolobous multiformis , the nitrite oxidiser Nitrococcus mobilis as well as from the genomes of other unrelated heterotrophic bacteria. These DNA sequences could be amplified from 0.01 ng of N. europaea genomic DNA or from 100 intact cells, and it was possible to detect Nitrosomonas DNA in a DNA mixture extracted from water samples drawn from a local oxidation pond.  相似文献   
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