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81.
Water, sediment, and shellfish from three Oregon estuaries were cultured for pathogenic Vibrio species. Non-O1 serovars of V. cholerae were the most common pathogenic Vibrio species recovered. Non-O1 V. cholerae were isolated from all three estuaries sampled, covering an area of about 170 miles along the Oregon coast. Non-O1 V. cholerae were isolated from water and sediment, but not shellfish, at temperatures ranging from 11 to 19°C and salinities of 2.3 to 26‰. Sixteen isolates representing 12 different non-O1 serovars were identified, while four non-O1 V. cholerae isolates failed to react with any of the 54 antisera tested. These results indicate that non-O1 V. cholerae serovars can be found over a large geographic area and under a variety of environmental conditions. These organisms are apparently an autochthonous component of these estuarine microbial communities.  相似文献   
82.
A medium was designed for the enrichment and enumeration of Vibrio fluvialis from environmental samples. The medium contains 1% peptone plus 4% sodium chloride and 5 micrograms of novobiocin per ml, pH 8.5. This V. fluvialis enrichment medium (FEM) was tested, in comparison with alkaline peptone (AP), in field samplings. A total of 177 samples (estuarine waters and sediment, sewage, and crabs) collected over a 14-month period were examined with FEM and with AP broth. Results showed that FEM was more effective than AP in detecting V. fluvialis, particularly from water and sewage samples with low salinities (less than 6%). The best recovery of V. fluvialis occurred when both enrichment media were used simultaneously.  相似文献   
83.
Vibrio cholerae O1 strains isolated from various sources in Japan over the years 1977 through 1987 were examined to confirm the presence or absence of the cholera enterotoxin (CT) gene and production of CT and to determine the kappa-phage type. The CT gene was detected in none of 225 isolates from natural waters but was present in all of the 10 isolates from environmental waters implicated in domestic cholera cases, in 64 strains (26.6%) of the 241 isolates from imported seafoods, in 43 strains (95.6%) of the 45 isolates from domestic cholera cases, and in 119 strains (93.7%) of the 127 isolates from imported cholera cases. The results suggest that the CT gene-positive strains of V. cholerae O1 have been imported into Japan through seafoods and/or by travelers. Sporadic cholera cases have resulted in contamination of the surrounding environment, but the CT gene-positive strains may not have persisted in natural waters to serve as a reservoir for epidemic cholera. The commercially available VET-RPLA kit (a latex agglutination kit for immunological detection of CT) detected production of CT in all of the CT gene-positive strains, indicating that there was no silent CT gene in the test strains. There was a strong correlation between the kappa-phage type and the presence or absence of the CT gene, suggesting a significant clonal difference between CT gene-positive and -negative strains. Five CT gene-negative strains isolated from imported cholera cases (travelers with mild diarrhea) induced a considerable amount of fluid accumulation in rabbit and/or suckling mouse intestines, indicating production of an enterotoxic factor(s) other than CT.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
84.
Recombinant human granulocyte colony-stimulating factor (rhG-CSF) was investigated for its clinical efficacy in the treatment of various types of neutropenia (3 cases with idiopathic neutropenia of suspected drug induction, 5 cases with idiopathic neutropenia of other origin, and 2 cases with cyclic neutropenia). Treatment with glycosylated rhG-CSF produced in the Chinese Hamster Ovary cells at dose levels of 2–5g/kg/day caused rapid increases of neutrophil counts associated with an improvement of the infection. In cyclic neutropenia patients, marked reduction in the duration of the neutropenic period was observed with rhG-CSF administration started before the period. Intercurrent stomatitis, which occurred in 1 patient, was markedly milder as compared to a previous episode which occurred during an untreated neutropenic period.The treatment of rhG-CSF was well tolerated and no adverse events were observed, nor was there any detectable anti-rhG-CSF antibody in any patients studied; hence the clinical use of rhG-CSF is considered to be safe.These results suggest beneficial effects of rhG-CSF on the recovery of neutrophil counts in cyclic and other types of idiopathic neutropenias, as well as for the treatment of neutropenia-associated infection.  相似文献   
85.
The effects of infusion of a large amount of aldosterone into the renal artery of isolated perfused hog kidney on the release of renin, prostaglandins (PG) and kinin and the excretion of urinary kallikrein were investigated. Infusion of aldosterone at a rate of 100 ng/min (100 to 800 ng/ml of perfusate) resulted in significant releases of renin, PG (PGE2, 6-0-PGF), and kinin and increase in urinary kallikrein. Infusion of aldosterone and an inhibitor of kallikrein, aprotinin, decreased the releases of renin, PG and kinin and infusion of aldosterone with indomethacin decreased the release of PG but increased that of kinin and urinary kallikrein without significant change in renin releases. These findings suggest that the release of renin by aldosterone may result from synergic effects of renal PG and the kallkrein-kinin system.  相似文献   
86.
Summary Optic fibers were implanted stereotaxically into the brain of immature male Japanese quail reared under short-day photoperiod (lights on from 1000 to 1800 h), and photosensitive sites in the hypothalamus were examined using gonadal growth and associated hormonal changes as the indices.In the subsequent experiments, bipolar (coaxial) electrodes were implanted chronically using predetermined coordinates for highly photosensitive sites. Henceforth the birds received brief electrical stimulation (square wave, 100 Hz, 100A, 2 min) once daily for 21 consecutive days. When the electrical stimulation was applied early in the dark period, marked gonadal growth was induced, but identical stimulation given in the light period resulted in no testicular growth. The response curve of testicular weight vs clock time of electrical stimulation has a prominent peak at 3 h after the onset of dark. Apparently, the neural complex in the photosensitive area of the quail hypothalamus responds to electrical stimulation as it does to light. We conclude that in photoperiodic birds the principal factor which determines the magnitude of gonadal responses is not the intensity of the stimulus but its timing (circadian phase).Abbreviations GnRH gonadotropin releasing hormone - LD light and dark - LED light emitting diode - CRT cathode ray tube - LH luteinizing hormone - OD outer diameter - ID inner diameter  相似文献   
87.
Abstract

Selective protection of the three hydroxyl groups of sugar moiety of nucleosides have been studied by enzyme-catalyzed esterification in organic solvents. Selectively protected products were obtained. The reaction provides an efficient method for selective protection of nucleosides.  相似文献   
88.
A papain-catalyzed reaction involving the covalent attachment of L-leucine ra-dodecyl ester [Agric. Biol. Chem., 44, 1979 (1980)] was applied to gelatin and succinylated fish protein concentrate. Proteinaceous surfactants formed were found suitable for emulsification of soybean oil. The emulsions prepared with these surfactants were characterized by having a variety of functional properties in terms of hardness, adhesiveness, viscosity and viscoelasticity. Any particular property could be reproduced by intentionally setting the proper conditions for emulsification; for example, the use of a high surfactant concentration resulted in gel formation. The functions of the proteinaceous surfactants were different in many respects from those of Tween-60 and a type of sucrose fatty acid ester used as controls. Several data were added explaining such differences. The feasibility of preparing a mayonnaise-like concentrated emulsion by use of the proteinaceous surfactants is discussed.  相似文献   
89.
Summary An ntrA (rpoN) mutant of Pseudomonas putida, in which the gene was insertionally inactivated, was constructed. The mutant cells did not have flagella, thus accounting for their poor motility. The mutant phenotype was complemented by introduction of the intact ntrA gene.  相似文献   
90.
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