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71.
Onondaga Lake, N.Y., failed to turnover in the spring of 1986 because of the strong chemical stratification under the ice that developed as a result of ionic discharges from an alkali plant. This stratification had a negative impact on the O2 resources of the lake, as the lower depleted layers of the lake were not replenished with O2. Anoxia and anaerobiesis in the bottom water expanded following ‘ice-out’. Comparison of characteristics observed for the winter through spring interval of 1986 with historic data indicates Onandaga Lake has failed to experience spring turnover in a number of years (approximately 7 of the last 18 yr) because of the ionic discharges from the alkali plant.  相似文献   
72.
ObjectiveTo evaluate a supraglottic airway device (SGAD) designed for rabbits in African pygmy hedgehogs (Atelerix albiventris) during inhalation anesthesia.Study designProspective, randomized, blinded experimental study.AnimalsA total of 12 adult African pygmy hedgehogs (seven male, five female).MethodsHedgehogs were placed in a chamber and anesthesia was induced using isoflurane in oxygen. Oropharyngeal endoscopy was performed and video recorded. The SGAD (v-gel R1) was inserted and connected to a Mapleson D circuit. Capnography, pulse oximetry and physiologic variables were measured during anesthesia, and lung inflation was tested at 10 and 20 cmH2O. With the SGAD temporarily disconnected, anesthetized hedgehogs were randomly positioned into right and left lateral, dorsal and sternal recumbency to evaluate the effect of a change in body position on SGAD placement. Oropharyngeal endoscopy was repeated at the end of anesthesia, and recovery time was recorded. Pre- and post-SGAD placement endoscopy videos were retrospectively reviewed and scored for gross trauma.ResultsThe median [interquartile range (IQR)] time to successful SGAD placement was 38 (16–68) seconds. The time to SGAD placement decreased as the study progressed. SGAD required repositioning in six hedgehogs, median 2.5 (IQR, 1–3.5) adjustments each, to successfully perform lung inflation or maintain capnography readings. Lung inflation at 10 cmH2O was successfully performed without leakage in nine animals, and in the other three animals after adjusting the SGAD at 1–2 time points. Inflation at 20 cmH2O was rarely achieved without an air leak. Changes in heart and respiratory rates during anesthesia were not clinically relevant. Median endoscopic scores were 0 (no lesions) for both pre-and postplacement.Conclusions and clinical relevanceThe SGAD was relatively quickly and easily placed, permitted lung inflation and caused no significant oropharyngeal damage. The SGAD is a practical option for airway management in African pygmy hedgehogs.  相似文献   
73.
Associations between benign and malignant neoplasms of the dog were quantitatively evaluated. Using histologically confirmed submissions and population-based methodology, canine benign tumors were significantly associated with both the unordered and subsequent development of additional distinct malignancies in the same dogs. A detailed examination of the methods indicated that these results are not likely due to methodologic artifact. The implication is that benign and malignant tumor development are associated and that the occurence of a benign neoplasm is an indicator of a parallel predisposition to malignancy.  相似文献   
74.
75.
Pseudomonas aeruginosa is associated with infectious endometritis in horses. Although infectious endometritis is often considered a venereal infection, there is relatively limited genotypic-based evidence to support this mode of transmission. The study sought to determine the relatedness between genital P. aeruginosa isolates collected from a limited geographical region using molecular strain typing. Enterobacterial repetitive intergenic consensus PCR typing was performed on 93 isolates collected between 2005 and 2009 from 2058 thoroughbred horses (including 18 stallions) at 66 studs. While P. aeruginosa was not detected in the stallions, 53/93 (57%) mares harbouring P. aeruginosa had clonally related strains, which included a single dominant genotype detected in 42 (45%) mares from 13 different studs. These novel findings suggest that most equine genital P. aeruginosa infections in this region may have been acquired from mechanisms other than direct horse to horse transmission. Instead, other potential acquisition pathways, as well as strain specific adaptation to the equine genital tract, should be investigated.  相似文献   
76.
We identified a previously unknown riboswitch class in bacteria that is selectively triggered by glycine. A representative of these glycine-sensing RNAs from Bacillus subtilis operates as a rare genetic on switch for the gcvT operon, which codes for proteins that form the glycine cleavage system. Most glycine riboswitches integrate two ligand-binding domains that function cooperatively to more closely approximate a two-state genetic switch. This advanced form of riboswitch may have evolved to ensure that excess glycine is efficiently used to provide carbon flux through the citric acid cycle and maintain adequate amounts of the amino acid for protein synthesis. Thus, riboswitches perform key regulatory roles and exhibit complex performance characteristics that previously had been observed only with protein factors.  相似文献   
77.
Excavation in the previously little-explored western portion of Olduvai Gorge indicates that hominid land use of the eastern paleobasin extended at least episodically to the west. Finds included a dentally complete Homo maxilla (OH 65) with lower face, Oldowan stone artifacts, and butchery-marked bones dated to be between 1.84 and 1.79 million years old. The hominid shows strong affinities to the KNM ER 1470 cranium from Kenya (Homo rudolfensis), a morphotype previously unrecognized at Olduvai. ER 1470 and OH 65 can be accommodated in the H. habilis holotype, casting doubt on H. rudolfensis as a biologically valid taxon.  相似文献   
78.
A key policy objective of many European Governments and their forestry departments is socially inclusive use of woodlands as use is a pre-requisite to enjoying many of the benefits afforded by woodland. However, access to woodlands is unequally distributed across British society and research suggests disconnect between the facilities provided and their suitability-for-use, given the wide range of reasons for visiting woodland. This research sought to inform woodland management and complement research into barriers to accessing woodland by investigating whether the design and provision of core access facilities may preclude certain user-groups. The research was carried out on the public forest estate of England; although the results are applicable to any woodland where public access is encouraged. The generic findings are applicable also to other greenspace types. Preferences in design were strongly influenced by the instrumentality (functionality) and aesthetic of an item – whether it was in-keeping with the woodland setting. Facility provision and upkeep are also important to woodland users. The study suggests that small changes in facility provision, including greater emphasis on naturalistic and rustic designs, provision of a range of pathway surface types and reducing the urbanisation of woodland, could increase the appeal of woodland to a wider demographic. Woodlands can fulfil a wide range of social functions. Where this is desirable, the woodland (new or existing) should be appropriately designed to reflect these intended roles and functions. This will require a range of facilities sympathetically provided.  相似文献   
79.
A novel series of substituted 3-phenyl benzoylpyrazoles were prepared and tested as potential grass herbicides. The targeted materials were prepared by three newly developed synthetic routes, which allowed a comprehensive study of the SAR (structure-activity relationships) of this series. The best combination of grass weed activity (Avena fatua L, Setaria viridis (L) Beauv and Alopecurus myosuroides Huds) and wheat selectivity was obtained with an alkoxy group in the 4-position of the phenyl ring. Activity was further enhanced by the presence of tert-butyl on the pyrazole and a methyl group at the C-2 position of the benzoyl moiety. The alkoxy-substituted 3-phenylbenzoylpyrazoles are a novel class of herbicides with potential utility for control of important grass weeds in cereals.  相似文献   
80.
A diagnostic project was initiated across the United States in 2006 to improve the understanding of porcine circovirus associated diseases (PCVAD) as well as to identify co-factors in PCVAD-affected farms. A Porcine circovirus-2 (PCV-2) DNA real-time polymerase chain reaction quantitation (qPCR) was established according to a published method and sera from a total of 23pig farms across the United States were examined for viral loads for PCV-2 and analyzed for any possible effects of Porcine reproductive and respiratory syndrome virus (PRRSV) vaccination on this parameter. Vaccination against PRRS resulted in significantly lower viral loads for PCV-2 in animals 13 wk or older compared with nonvaccinated animals, but vaccination of pigs against PRRS had no effect on qPCR results for PCV-2 in 4- to 12-week-old pigs. Interestingly, PRRS vaccinates had significantly lower viral loads when peak wasting disease was observed in the herds. The qPCR method for PCV-2 proved to be an important tool for help in the antemortem diagnosis of PCVAD as well as in the monitoring of infection dynamics.  相似文献   
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