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91.
D. L. Barnard J. C. Dean Hart V. J. Marmion S. K. R. Clarke 《BMJ (Clinical research ed.)》1973,2(5859):165-168,169
In an investigation of an outbreak of adenovirus type 8 infection involving over 40 people it was found that the infection spread initially within the eye hospital, but subsequently involved several family contacts and two local hospitals for mentally subnormal patients. Presumptive diagnosis should be possible before subepithelial opacities have developed provided an adequate history is taken, and had that been done in this outbreak it is reasonable to suppose that many cases could have been prevented. 相似文献
92.
The neurotensin receptor protein, solubilized with digitonin/asolectin from bovine cerebral cortex membranes, was purified to apparent homogeneity by affinity chromatography using immobilized neurotensin. The product exhibits saturable and specific binding of [3,11-tyrosyl-3,5-3H]neurotensin with an apparent affinity (Kd = 5.5 nM) comparable to that measured in intact membranes and crude soluble extracts. The affinity-purified material, after reduction with 100 mM dithiothreitol, in denaturing gel electrophoresis showed a single polypeptide of Mr 72,000. Under nonreducing conditions the apparent Mr, however, was 50,000, suggesting the presence of intramolecular disulfide bonds. The purified neurotensin receptor was judged to be homogeneous, in that (i) only a single polypeptide was detectable; and (ii) the overall purification was 30,000-50,000-fold, giving a specific neurotensin-binding activity close to the theoretical maximum. 相似文献
93.
94.
N. McKeganey M. Barnard A. Leyland I. Coote E. Follet 《BMJ (Clinical research ed.)》1992,305(6857):801-804
OBJECTIVES--To identify the extent of HIV infection and injecting drug use among female streetworking prostitutes in Glasgow; to estimate the size of the female streetworking prostitute population in the city; and to estimate the number of HIV positive women working as prostitutes on the streets in Glasgow. DESIGN--Observation and interviewing of female prostitutes over seven months in red light district; analysis of saliva samples for presence of antibodies to HIV; capture-recapture approach to estimating the size of the female streetworking prostitute population. SETTING--Glasgow. SUBJECTS--206 female streetworking prostitutes. MAIN OUTCOME MEASURES--Number of women with antibodies to HIV, self reported use of injecting drugs, history of contact with 206 women. RESULTS--Saliva samples were requested from 197 women; 159 (81%) provided samples. Four (2.5%, 95% confidence interval 0.7%-6.3%) of the samples were positive for HIV, all of which had been provided by women who injected drugs. Of the 206 streetworking women contacted 147 (71%) were injecting drug users. About 1150 women are estimated to work on the streets in Glasgow over a 12 month period. CONCLUSIONS--HIV is not as widespread among female prostitutes as many reports in the tabloid press suggest. A greater proportion of female streetworking prostitutes in Glasgow are injecting drugs than has been reported for other British cities. 相似文献
95.
QUANTITATIVE STUDIES ON ENZYMES IN STRUCTURES IN STRIATED MUSCLES BY LABELED INHIBITOR METHODS : II. Confirmation of Radioautographic Measurement by Liquid-Scintillation Counting 总被引:1,自引:1,他引:0
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Fragments of mouse diaphragm and sternomastoid muscles were incubated in diisopropyl-fluorophosphate (DFP)-3H in conditions known to saturate all the available DFP-sensitive reaction sites. After being extensively washed, the enzyme acetylcholinesterase (AChase) was specifically reactivated by treatment with pyridine-2-aldoxime methiodide (2-PAM). The radioactive DP-groups released into solution by 2-PAM were measured by liquid scintillation counting, and related to the known number of motor endplates present. Considerable difficulty was encountered in reducing the excess, adsorbed radioactivity to acceptable levels: long washing routines, extraction with organic solvents, and removing excess muscle fiber by microdissection were necessary. Six experiments gave a mean value of 2.4 x 107molecules AChase per sternomastoid endplate, in reasonable agreement with the previously reported measurements by radioautography. 相似文献
96.
97.
Accumulating wing damage affects foraging decisions in honeybees (Apis mellifera L.) 总被引:1,自引:0,他引:1
Abstract. 1. Nectar-foraging honeybees ( Apis mellifera ) on lavender ( Lavandula stoechas ) appear to forage so as to maximise net energy return from foraging bouts; however, evidence from other studies suggests that foraging has a detrimental effect on survival, due at least in part to physiological deterioration of the flight mechanism. But foragers also acquire wing damage during foraging, which may increase foraging effort and reduce foraging lifespan.
2. The accumulation of damage over time and its effects on foraging flight and flower choice were studied in the field using a system in which the criteria for flower preference by foragers was known from previous work. Wing damage accumulated exponentially over time and resulted in foragers becoming less choosy about the flowers they visited.
3. Damage added experimentally contributed independently to the effect on choosiness. Effects of wing damage (natural and added experimentally) were also independent of those of a relative measure of age, which related in an inconsistent way to changes in foraging preferences. 相似文献
2. The accumulation of damage over time and its effects on foraging flight and flower choice were studied in the field using a system in which the criteria for flower preference by foragers was known from previous work. Wing damage accumulated exponentially over time and resulted in foragers becoming less choosy about the flowers they visited.
3. Damage added experimentally contributed independently to the effect on choosiness. Effects of wing damage (natural and added experimentally) were also independent of those of a relative measure of age, which related in an inconsistent way to changes in foraging preferences. 相似文献
98.
G. Kemp J.O. Dolly E.A. Barnard C.E. Wenner 《Biochemical and biophysical research communications》1973,55(3):A607-A613
Incorporation of a fraction isolated from rat diaphragm muscle that contained the specific endplate cholinergic receptor into phospholipid bilayer membranes resulted in the production of an acetylcholine-stimulated conductance increment of large magnitude. The acetylcholine-stimulated conductance shows several characteristics of the post-synaptic excitable system. 相似文献
99.
Effects of peptidoglycans from periodontal pathogens on selected biological activities of CD-1 murine peritoneal macrophages 总被引:2,自引:0,他引:2
Resident CD-1 murine peritoneal macrophages were exposed to various concentrations of purified peptidoglycan isolated from members of the genera Bacteroides, Eikenella, and Actinomyces. Macrophage viability, the release of lysozyme, acid phosphatase, and prostaglandins E1 and E2 were assayed as a function of peptidoglycan concentration and time. Macrophages responded as a function of peptidoglycan concentration with increased release of acid phosphatase and prostaglandins; all cells remained greater than 90% viable during the course of the experiments. However, concentrations of peptidoglycan greater than 50 micrograms/mL were toxic to the macrophages, while the peptidoglycan from B. capillus strain 925.08 and Actinomyces viscosus strain T14AV consumed complement by both the classical and the alternate pathways. Cellular lysozyme activity and phagocytosis of Saccharomyces cerevisiae were significantly reduced in the presence of peptidoglycan. When viewed by scanning electron microscopy, the activated macrophages were rounded, lacked distinct pseudopod extensions, and possessed an increased number of microvilli and plasma membrane associated vesicles. These morphological alterations occurred as early as 3 h. Transmission electron microscopy revealed the purified peptidoglycan to have been taken up into numerous phagosomes; however, even after 24 h incubation, it was only partially degraded. 相似文献
100.