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11.
The population of a biological system in a sewage treatment plant is formed of a fortuitous assemblage of microorganisms, members of which are continually dropped out while additional members are recruited. Many of these organisms are active throughout the year. Fewer yeasts than filamentous fungi are found by the plating technique. The population is about evenly divided between species producing their spores in dry states and in wet states. The fungus population includes species which under certain circumstances are able to use a wide variety of substrates from simple sugars to complex carbohydrates and hydrocarbons.
Much of the material included here was Presented at the 23rd Industrial Waste Conference Purdue University, Lafayette, Indiana May 7–9, 1968 相似文献
Zusammenfassung Die Population eines biologischen Systems in einem Kloakenwasser-Behandlungs-werk ist durch ein zufälliges Zusammentreffen von Mikroorganismen geformt, deren Mitglieder fortwährend ausfallen, während andere hinzukommen. Viele dieser Mikroorganismen sind während des ganzen Jahres aktiv. Weniger Hefen denn Fadenpilze sind mit der Plattentechnique gefunden. Die Population ist ungefähr gleichmäßig unter den Arten verteilt, die die Sporen in trockenem wie in feuchtem Zustand produzieren. Die Pilzpopulation umfaßt Arten, die unter gewissen Umständen fähig sind, eine große Varietät von Nährmaterial, von einfachen wie auch komplexen Kohlenstoffhydraten und Kohlenstoffhydraten zu benutzen.
Much of the material included here was Presented at the 23rd Industrial Waste Conference Purdue University, Lafayette, Indiana May 7–9, 1968 相似文献
12.
Pyrogenic responses, ranging up to 4.8 F, were induced in cats by oral administration of highly purified staphylococcal enterotoxin B in doses from 10 to 100 mug/kg. Fever was a more sensitive indicator of intoxication than was emesis. Highly purified preparations of enterotoxin A, whether administered intravenously (0.01 to 1.0 mug/kg), orally (10 to 25 mug/kg), or into the cerebral ventricles (0.005 to 0.020 mug in 0.20 ml), were also pyrogenic in cats. Tolerance to the pyrogenic activity was produced by repeated intravenous injection of a given dose of enterotoxin A but not by repeated intracerebroventricular injection. Enterotoxin A was more potent than enterotoxin B after intravenous injection in causing both fever and emesis. Cross-tolerance could not be demonstrated between enterotoxin A and enterotoxin B or Salmonella typhosa endotoxin. This lack of cross-tolerance plus the inability of large oral doses (100 to 4,700 mug/kg) of endotoxin to cause fever or emesis indicate that the reported responses were attributable to the specific toxins administered and not to contamination by other pyrogens. 相似文献
13.
Wesley S. Moore F. William Blaisdell Albert D. Hall 《The Western journal of medicine》1964,100(2):92-96
The presenting manifestations of polycythemia vera are often complications involving the vascular system. These include myocardial infarction, cerebro-vascular accidents and ischemic changes in the extremities.The concept of increased atherogenesis in cases of polycythemia vera has been questioned. A possible mechanism by which small, otherwise subclinical atheromatous plaques produce ischemic symptoms in patients with polycythemia vera is discussed. The blood in polycythemic patients has been shown to have an increased viscosity resulting in a prolonged circulation time. If a small atheromatous plaque is present in association with increased blood viscosity, this combination may well produce ischemic symptoms. This explains why treatment of polycythemia vera, with restoration of blood to normal viscosity, often reverses the patient''s ischemic symptoms.Two cases of polycythemia vera here reported, in which the presenting manifestations were gangrenous extremities, emphasize the need for prompt diagnosis and treatment of polycythemia vera. In the first case, early recognition and treatment of polycythemia vera successfully reversed the ischemic changes in the extremities, while failure of early recognition and treatment in the second case resulted in two major amputations. 相似文献
14.
Beverly A. Mock Marianne Krall Christine A. Kozak Muriel N. Nesbitt O. Wesley McBride Jean-Christophe Renauld Jacques Van Snick 《Immunogenetics》1990,31(4):265-270
Mouse and human cDNA clones encoding the T-cell and mast cell growth factor P40, now designated IL-9, were used to identify DNA restriction fragment length polymorphisms (RFLPs) in sets of somatic cell hybrids and between inbred strains of mice and interspecific backcross progeny. Segregation of mouse and human chromosomes among somatic cell hybrids indicated a location on mouse chromosome 13 and human chromosome 5. RFLPs were identified among inbred strains of mice. Analysis of chromosome 13 alleles for Tcrg, Dhfr, and Il-9 in an interspecific cross between Mus musculus and NFS/N or C58/J mice indicates that IL-9 is distal to Tcrg and Proximal to Dhfr. 相似文献
15.
Glenn T. Howe Gary Gardner Wesley P. Hackett Glenn R. Furnier 《Physiologia plantarum》1996,97(1):95-103
In trees and other woody perennial plants, short days (SDs) typically induce growth cessation, the initiation of cold acclimation, the formation of a terminal bud and bud dormancy. Phytochrome control of SD-induced bud set was investigated in two northern clones of black cottonwood (Populus trichocarpa Torr. & Gray) by using night breaks with red light (R) and far-red light (FR). For both clones (BC-1 and BC-2), SD-induced bud set was prevented when R night breaks as short as 2 min were given in the middle of the night. When night breaks with 2 min of R were immediately followed by 2 min of FR, substantial reversibility of bud set was observed for BC-1 but not for BC-2. By comparing the effects of the R night breaks on bud set and the length of specific internodes, we determined that the R night breaks influenced internode elongation in two opposing ways. First, the addition of a R night break to the SD treatment prevented the cessation of internode elongation that is associated with bud set. Those internodes that would not have elongated under SDs (and would have been found within the terminal bud) elongated in the R treatment. Second, the R night breaks decreased internode length relative to the long-day (LD) control. In contrast to the clonal differences in reversibility that we observed for bud set, the decrease in internode length (i.e. the second effect of R) was R/FR reversible in both clones. Based on these results, we conclude that internode elongation is influenced by two distinct types of phytochrome-mediated response. The first response is a typical response to photpperiod, whereas the second response is a typical “end-of-day” response to light quality. Our results demonstrate that SD-induced bud set in black cottonwood is controlled by phytochrome but that clonal differences have an important influence on the R/FR reversibility of this response. The availability of an experimental system in which SD-induced bud set is R/FR reversible will be valuable for studying the physiological genetics of photoperiodism in trees. 相似文献
16.
Wesley Hicks Robert Ward David Edelstein Leon Hall Anthony Albino Robert Hard Bonnie Asch 《Cell biology international》1995,19(4):301-306
The cytokertatins in respiratory epithelial cells (REC) of human nasal polyps and turbinates were analyzed by immunohistochemistry. Cytokeratin 19 (CK19) was present in all REC, CK5 and 14 were expressed primarily in basal cells, and CK7, 8, and 18 were found in suprabasal cells. Differences in cytoplasmic locations were also apparent among the individual cytokeratins. CK13 was not detected in any REC of these tissues. The results indicate the profile of cytokeratins in REC of human nasal polyps and turbinates is essentially identical to that of REC in the more distal respiratory tract. 相似文献
17.
Christon J. Hurst Janet C. Blannon Rachel L. Hardaway Wesley C. Jackson 《Applied microbiology》1994,60(9):3462-3465
This study examined whether the practice of incorporating either tetrazolium red or tetrazolium violet dye into plaque assay medium deleteriously influences plaque assay titers. Representative members of six different virus families were studied: Cystoviridae (ϕ6), Leviviridae (MS2), Microviridae (ϕX174), Myoviridae (T2), Podoviridae (P22), and Siphoviridae (Denver, T1, and VD13). Each of the members of the Podoviridae and Siphoviridae families appeared to be suppressed by either one or both dyes at a 300-μg/ml concentration. The chosen representatives of the other bacteriophage families were not suppressed by either dye at a 300-μg/ml concentration. Subsequent trials revealed no suppression of Podoviridae or Siphoviridae plaque assay titers when members of these virus families were tested with the same two dyes at the lower concentrations of 150 and 50 μg/ml. Interestingly, the bacteriophage families whose members were affected by the dyes have additional commonality in that they are the two bacteriophage families whose members possess both double-stranded DNA genomes and noncontractile tails. 相似文献
18.
A Strategy for Rotation of Different Bacteriophage Defenses in a Lactococcal Single-Strain Starter Culture System 总被引:6,自引:5,他引:1
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A new strategy for starter culture rotations was developed for a series of phage-resistant clones genetically derived from a single strain of Lactococcus lactis subsp. lactis. Phage-resistant derivatives carrying different defense systems were constructed via conjugation with various plasmids encoding abortive infection (Abi/Hsp) and/or restriction and modification (R/M) systems of different specificity. The plasmids included pTR2030 (Hsp+ R+/M+), pTN20 (Abi+ R+/M+), pTRK11 (R+/M+), and pTRK68 (R+/M+). Selected phage-resistant transconjugants or transformants were evaluated in different rotation sequences through cycles of the Heap-Lawrence starter culture activity test in milk contaminated with phage and whey from the previous cycle. When used in consecutive sequence, derivative strains carrying the R/M systems encoded by pTN20, pTRK11, and pTRK68 retarded phage development when the initial levels of phage contamination were below 102 PFU/ml but not when levels were increased to 103 PFU/ml. Use of a derivative bearing pTR2030 (Hsp+ R+/M+) at the beginning of the rotation prevented phage development, even when the initial levels of phage contamination were high (106 PFU/ml). Alternating the type and specificity of R/M and Abi defenses through the rotation prevented phage proliferation and in some cases eliminated contaminating phages. A model rotation sequence for the phage defense rotation strategy was developed and performed successfully over nine cycles of the Heap-Lawrence starter culture activity test in the presence of high-titer commercial phage composites. This phage defense rotation strategy is designed to protect a highly specialized Lactococcus strain from phage attack during continuous and extended use in the dairy industry. 相似文献
19.
The purpose of this article is to describe the treatment of a 45-year-old male with a hyperfunctional voice disorder by a biofeedback therapist and a speech-language pathologist. The interdisciplinary approach to the treatment of this voice disorder involved the combined use of traditional voice therapy techniques and EMG biofeedback procedures together with cognitive behavioral therapy. Voice therapy was facilitated through the use of a computer-based, speech-monitoring system. The remediation of this voice disorder was attributed to the collaborative efforts of two professionals representing diverse professional training and treatment protocols. The results showed reductions in muscle activity in the infrahyoid and laryngeal areas as well as improved use of proper breathing and voicing onset behaviors. Follow-up at 10 and 15 months posttreatment intervals indicated that the client had retained all target voice skills and the tension reduction/biofeedback skills. Results suggest that interdisciplinary, collaborative efforts using biofeedback and voice therapy can prove beneficial in the treatment of hyperfunctional voice disorders.Note: Neither author has been compensated in any way for the use of the CAFET System nor does either have any financial interest in the company. 相似文献
20.
The speckled peacock bass Cichla temensis is a popular sport and food fish that generates substantial angling tourism and utilitarian harvest within its range. Its popularity and value make this species important for management and a potential aquaculture candidate for both fisheries enhancement and food fish production. However, little is known of optimal physiochemical conditions in natural habitats, which also are important for the development of hatchery protocols for handling, spawning and grow-out. Speckled peacock bass have been documented to have high sensitivity to extreme temperatures, but the metabolic underpinnings have not been evaluated. In this study, the effects of temperature (25, 30 and 35°C) on the standard metabolic rate (SMR) and lower dissolved oxygen tolerance (LDOT) of juvenile speckled peacock bass (mean ± standard error total length 153 ± 2 mm and wet weight 39.09 ± 1.37 g) were evaluated using intermittent respirometers after an acclimation period of 2 weeks. Speckled peacock bass had the highest SMR at 35°C (345.56 ± 19.89 mgO2 kg−1 h−1), followed by 30°C (208.16 ± 12.45 mgO2 kg−1 h−1) and 25°C (144.09 ± 10.43 mgO2 kg−1 h−1). Correspondingly, the Q10, or rate of increase in aerobic metabolic rate (MO2) relative to 10°C, for 30–35°C was also greater (2.76) than from 25 to 30°C (2.08). Similarly, speckled peacock bass were the most sensitive to hypoxia at the warmest temperature, with an LDOT at pO2 of 90 mmHg (4.13 mg l−1) at 35°C compared to pO2 values of 45 mmHg (2.22 mg l−1) and 30 mmHg (1.61 mg l−1) at 30 and 25°C, respectively. These results indicate that speckled peacock bass are sensitive to temperatures near 35°C, therefore we recommend managing and rearing this species at 25–30°C. 相似文献