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11.
Measurements were made of fecal pellets for captive brow-antlered deer (Cervus eldi eldi) from different age and sex classes. Pellet measurements increased linearly with increases in age, except for length and width measurements in males. Differences in dimensions were statistically significant between sexes and among some age classes. This procedure may be useful in differentiating between the sexes, and to some extent between ages, of wild-living individuals. © 1993 Wiley-Liss, Inc. 相似文献
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A component of the chloroplastic protein import apparatus is targeted to the outer envelope membrane via a novel pathway. 总被引:28,自引:3,他引:25 下载免费PDF全文
A chloroplastic outer envelope membrane protein of 75 kDa (OEP75) was identified previously as a component of the protein import machinery. Here we provide additional evidence that OEP75 is a component of protein import, present the isolation of a cDNA clone encoding this protein, briefly describe its developmental expression and tissue specificity, and characterize its insertion into the outer envelope membrane. OEP75 was synthesized as a higher molecular weight precursor (prOEP75) which bound to isolated chloroplasts in an in vitro import assay and subsequently was processed to the mature form (mOEP75). During this import assay, two proteins intermediate in size between prOEP75 and mOEP75 were detected. One of these intermediates was also detected in chloroplast envelopes isolated from young pea leaves. Binding and processing of prOEP75 required ATP and one or more surface-exposed proteinaceous components, and was competed by prSSU, a stromal-targeted protein. We propose that the N-terminus of the prOEP75 transit peptide acts as a stromal-targeting domain and a central, hydrophobic region of this transit peptide acts as a stop-transfer domain. A complex route of insertion and processing of prOEP75 may exist to ensure high fidelity targeting of this import component. 相似文献
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Human pathogenic viruses at sewage sludge disposal sites in the Middle Atlantic region. 总被引:6,自引:2,他引:4 下载免费PDF全文
Human enteric viruses were detected in samples of water, crabs, and bottom sediments obtained from two sewage sludge disposal sites in the Atlantic Ocean. Viruses were isolated from sediments 17 months after the cessation of sludge dumping. These findings indicate that, under natural conditions, viruses can survive for a long period of time in the marine environment and that they may present potential public health problems to humans using these resources for food and recreation. The isolation of viruses in the absence of fecal indicator bacteria reinforces previous observations on the inadequacy of these bacteria for predicting the virological quality of water and shellfish. 相似文献
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Regeneration of pleated filters used to concentrate enteroviruses from large volumes of tap water. 总被引:2,自引:1,他引:1 下载免费PDF全文
Pleated cartridge filters are capable of concentrating enteroviruses from large volumes (well over 2,000 liters) of tap water. These epoxy-fiberglass filters can be regenerated if they are treated with 0.1 N NaOH or autoclaved to inactivate any contaminating virus. The regenerated filters regained their ability to concentrate viruses from water at high flow rates. 相似文献
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Vasoactive intestinal peptide (VIP) caused a dose-dependent fall in lower esophageal sphincter (LES) pressure and dose-dependent contractions in the body of the esophagus. The response to VIP in the esophagus or LES was not modified by atropine, phentolamine, haloperidol, pyrilamine, methysergide, indomethacin and tetrodotoxin, showing that it exerts direct action at the esophageal smooth muscle. These studies suggest that VIP causes contraction in the esophageal body and relaxation of the LES by a direct action on the smooth muscle. It is possible that VIP may be the common mediator of noncholinergic, nonadrenergic neurons that cause relaxation of the lower esophageal sphincter and contraction in the esophageal body. 相似文献
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S R Farrah C P Gerba S M Goyal C Wallis J L Melnick 《Applied and environmental microbiology》1977,33(2):308-311
Pleated cartridge filters are capable of concentrating enteroviruses from large volumes (well over 2,000 liters) of tap water. These epoxy-fiberglass filters can be regenerated if they are treated with 0.1 N NaOH or autoclaved to inactivate any contaminating virus. The regenerated filters regained their ability to concentrate viruses from water at high flow rates. 相似文献
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Capture of latex beads, bacteria, endotoxin, and viruses by charge-modified filters. 总被引:6,自引:6,他引:0 下载免费PDF全文
This report demonstrates how electropositive filters can be used to enhance the removal of microorganisms and other negatively charged particles from water. It was shown that electropositive depth filters were capable of adsorbing viruses and endotoxins many times smaller than the average pore size of the filter. Electronegative filters of similar porosity or electropositive filters that had been treated to destroy the positive charge were almost ineffective under similar conditions for the removal of viruses and small latex spheres. The results of this study indicate that electropositive filters are highly effective in the removal of a wide range of contaminants over a wide range of pH values and ionic conditions. 相似文献