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41.
In swine, the nasal turbinate epithelium is both a site of swine herpesvirus 1 (pseudorabies virus, PRV) replication and a tissue affected by toxin fromPasteurella multocida serogroup D. We examined the effects of exposure to PRV and exposure to toxin in mice, swine, and nasal turbinate cell cultures. Increased mortality in mice was observed when nonlethal doses of PRV (1000 or 100 plaque-forming units, PFU) were administered along with nonlethal doses (60–200 ng/kg) of toxin. In swine, clinical disease and death in adult pigs was observed after an intradermal injection of toxin (20 ng/kg) and intranasal exposure to 1000 PFU/kg of PRV. Nasal turbinate cell cultures incubated with toxin and PRV had increased protein synthesis, DNA synthesis, and increased recovery of virus particles. These findings indicate that a toxin fromP. multocida serogroup D enhances swine herpesvirus 1 replication and lethality in cell cultures and animal models.  相似文献   
42.
Surface polysaccharides from five strains ofVibrio anguillarum were studied by means of immunoelectrophoretic procedures. The study suggested existence of two new K antigens, displaying cross-reactivity, in strains derived from diseased feral fish. The importance of a detailed serologic characterization of isolates for ecologic and epidemiologic studies ofV. anguillarum is considered.  相似文献   
43.
Summary Serotonin-like immunoreactivity was investigated in the pineal complex of the golden hamster by use of the indirect immunohistochemical technique. The superficial and deep portions of the pineal gland, and also the pineal stalk exhibited an intense cellular immunoreaction for serotonin. In addition, perivascular serotonin-immunoreactive nerve fibers were observed. Some serotonin-immunoreactive processes of the pinealocytes terminated on the surface of the ventricular lumen in the pineal and suprapineal recesses, indicating a receptive or secretory function of these cells. Several serotonin-immunoreactive processes connected the deep pineal with the habenular area. One week after bilateral removal of both superior cervical ganglia the serotonin immunoreaction of the entire pineal complex was greatly decreased. However, some cells in the pineal complex, of which several exhibited a neuron-like morphology, remained intensively stained after ganglionectomy. This indicates that the indoleamine content of some cells in the pineal complex of the golden hamster is independent of the sympathetic innervation.Supported by a Grant from the Italian Society for Veterinary Sciences  相似文献   
44.
TherglB gene ofEscherichia coli codes for a restriction activity that cleaves the hydroxymethylated DNA of T2 and T4 phages. Earlier mapping data placed the gene at 98.39 min counterclockwise to thehsd operon. Genetic analysis of the in vivo gene fusions with fusion-transducing phages established the location of therglB gene next to thehsdS gene of thehsdRMS cluster. The methodology used in this study could be extended to similar in vivo physical mapping of closely linked genes.  相似文献   
45.
Populations of pathogenic Pseudomonas syringae pv. syringae were monitored on apparently healthy leaves, blossoms, and fruit from two apple orchards with known histories of blister bark and a pear orchard with a known history of blossom blast. Populations on blossoms and fruits were higher on pears than on apples. Yellow-pigmented, non-pathogenic bacteria might have suppressed or masked the presence of P. syringae pv. syringae on apple trees. Populations of P. syringae pv. syringae on apple and pear leaves fluctuated sharply but higher levels generally occurred during the 1984/85 growing season than during the drier 1983/84 season. This investigation indicates that the resident phase of P. syringae pv. syringae is probably a major source of inoculum for apple blister bark and pear blossom blast in South Africa.  相似文献   
46.
Surface electromyography provides a very valuable set of information when used diagnostically with pain-related disorders. Unfortunately, most researchers and clinicians limit their investigation to only one level of diagnostic information available concerning the neuromuscular system. This article develops and encourages the clinician/researcher to consider three levels of diagnostic information: emotional, organ-related, and postural aspects. The theoretical background and diagnostic procedures used to investigate each is presented. Differential treatment considerations, given differential diagnostic findings, are discussed.  相似文献   
47.
In cyanobacteria, the glutamine synthetase-L-glutamine-2-oxoglutarate aminotransferase (GS-GOGAT) pathway is the major ammonia-assimilating route. The GS ofAnabaena doliolum was synthesized more under N2-fixing conditions, followed by ammonium, nitrate, and nitrite as nitrogen sources. The activities of both the glutamine synthetase, Mg2+-dependent biosynthetic and Mn2+-dependent -glutamyl transferase were optimum at pH 7. The active site of the enzyme bears sulfhydryl (-SH) groups; this was confirmed with the-SH group inhibitors, para-chloromercuribenzoate (pCMB) and N-ethylmaleimide (NEM). The biosynthetic and -glutamyl transferase activities showed specificity for the divalent cations, Mg2+ and Mn2+, respectively. The other divalent cations Co2+, Cu2+, and Ni2+ were poor substitutes. This enzyme also required these divalent cations to stabilize its structure and function under extreme conditions such as high and low temperatures and urea denaturation. The glutamate analogl-methionine-d,l-sulfoximine, inactivated the enzyme, whereas the GOGAT inhibitor, azaserine, had no effect on the enzyme activity. The GS enzyme required de novo protein synthesis.  相似文献   
48.
49.
The Tamang women tea-labouren of Jalpaiguri district show no significant difference in age at menopause among their three «migration status» groups, viz., MO, M1 and M2+. The mean age at menopause is 47.3±4.26 and the median age is 47.68 years. A significant difference occurs between the observed mean age at menopause and 45 years, which is generally taken to be the menopausal age by convention. These Tamang women seem to be similar to other hill women in respect of age at menopause.  相似文献   
50.
Two sessions of relaxation instructions were administered under high and low expectancy conditions. Fifty-four college students scoring high on a self-report measure of anxiety served as subjects. Live and taped abbreviated progressive muscle relaxation instructions and a self-relaxation condition were equally effective in reducing within-session self-report and physiological indices of anxiety. High expectancy instructions led to greater reductions in heart rate than did low expectancy instructions. Factors controlling anxiety reduction during relaxation therapies are discussed.This experiment was submitted by the first author in partial fulfillment for a master of science degree at VPI and SU. The authors would like to thank Jean Sales and Dan Fones for their help in this investigation. The First author is now at Johns Hopkins Hospital, Baltimore. The second author is currently at the Department of Neurology, University of Wisconsin-Madison.  相似文献   
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