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171.
CASE DESCRIPTION-4 dogs were evaluated because of recurrent urinary tract infections. CLINICAL FINDINGS-All dogs had recurrent urinary tract infections and similar clinical signs; 3 dogs had urinary incontinence. Digital vaginal examination revealed vestibulovaginal stenosis in all dogs, which was confirmed by results of contrast vaginourethrography. From image measurements, the vestibulovaginal ratio (ratio of the height of the vestibulovaginal junction to the maximum height of the vagina on a lateral vaginourethrogram) was calculated for each dog. Three dogs had severe stenosis (vestibulovaginal ratio, < 0.20; severe stenosis is defined as a vestibulovaginal ratio < 0.20), whereas the fourth dog had moderate stenosis (vestibulovaginal ratio, 0.24; ratio range for moderate stenosis is 0.20 to 0.25). TREATMENT AND OUTCOME-All dogs were anesthetized for surgical correction of the vestibulovaginal stenosis. Vaginal resection and anastomosis of the stenosis was performed in all 4 dogs, with 1 dog also undergoing episioplasty. Complete resolution of clinical signs was apparent in 3 dogs; 1 dog had postoperative complications including pollakiuria and stranguria, which resulted in rectal and vaginal prolapse. This dog underwent ovariohysterectomy, after which clinical signs resolved. All dogs had resolution of urinary tract infections at the time of follow-up (6 to 8 months after surgery). CLINICAL RELEVANCE-Resection and anastomosis may resolve recurrent urinary tract infections in dogs with severe or moderate vestibulovaginal stenosis. Episiotomy was not necessary for success of surgical treatment, and overall, that procedure increased morbidity, the severity of intraoperative hemorrhage, and duration of surgery.  相似文献   
172.
Shishkoff N 《Phytopathology》2011,101(12):1457-1464
Foliar hosts of Phytophthora ramorum are often susceptible to root infection but the epidemiological significance of such infections is unknown. A standardized test system was developed to quantify inoculum in runoff from root-infected Viburnum tinus ?Spring Bouquet? or Rhododendron ?Cunningham's White? cuttings. Cuttings of both species gave off a maximum amount of inoculum 1 to 3 weeks after inoculation. The greatest amount of inoculum was recovered from Viburnum roots that were 48 to 70 days old at the time of inoculation, or roots incubated at 15 to 20?C rather than 25?C. Inoculum in runoff from inoculated Viburnum roots was similar for four different isolates of P. ramorum representing both the NA1 and EU1 lineages. When Rhododendron cuttings were inoculated with P. ramorum, P. citricola, or P. cactorum, inoculum of all three pathogens was recovered from runoff, with the highest amount recovered from plants inoculated with P. citricola, followed by the other two. Compared with the other two pathogens, P. ramorum colonized root tissue to a smaller extent. The epidemiology of root infection by P. ramorum is important in itself but the assay might lend itself for use in risk analysis for root infection of other plant species and evaluation of control measures, and also shed light on other root-infecting Phytophthora spp.  相似文献   
173.
Nuclear pore complexes (NPCs) facilitate nucleocytoplasmic transport. These massive assemblies comprise an eightfold symmetric scaffold of architectural proteins and central-channel phenylalanine-glycine-repeat proteins forming the transport barrier. We determined the nucleoporin 85 (Nup85)*Seh1 structure, a module in the heptameric Nup84 complex, at 3.5 angstroms resolution. Structural, biochemical, and genetic analyses position the Nup84 complex in two peripheral NPC rings. We establish a conserved tripartite element, the ancestral coatomer element ACE1, that reoccurs in several nucleoporins and vesicle coat proteins, providing structural evidence of coevolution from a common ancestor. We identified interactions that define the organization of the Nup84 complex on the basis of comparison with vesicle coats and confirmed the sites by mutagenesis. We propose that the NPC scaffold, like vesicle coats, is composed of polygons with vertices and edges forming a membrane-proximal lattice that provides docking sites for additional nucleoporins.  相似文献   
174.
The high photostability of DNA is commonly attributed to efficient radiationless electronic relaxation processes. We used femtosecond time-resolved fluorescence spectroscopy to reveal that the ensuing dynamics are strongly dependent on base sequence and are also affected by higher-order structure. Excited electronic state lifetimes in dG-doped d(A)20 single-stranded DNA and dG.dC-doped d(A)20.d(T)20 double-stranded DNA decrease sharply with the substitution of only a few bases. In duplexes containing d(AGA).d(TCT) or d(AG).d(TC) repeats, deactivation of the fluorescing states occurs on the subpicosecond time scale, but the excited-state lifetimes increase again in extended d(G) runs. The results point at more complex and molecule-specific photodynamics in native DNA than may be evident in simpler model systems.  相似文献   
175.
The ratio of males to females in a species is often considered to be relatively constant, at least over ecological time. Hamilton noted that the spread of "selfish" sex ratio-distorting elements could be rapid and produce a switch to highly biased population sex ratios. Selection against a highly skewed sex ratio should promote the spread of mutations that suppress the sex ratio distortion. We show that in the butterfly Hypolimnas bolina the suppression of sex biases occurs extremely fast, with a switch from a 100:1 population sex ratio to 1:1 occurring in fewer than 10 generations.  相似文献   
176.
Using a rodent malaria model, we found that exposure to surfaces treated with fungal entomopathogens following an infectious blood meal reduced the number of mosquitoes able to transmit malaria by a factor of about 80. Fungal infection, achieved through contact with both solid surfaces and netting for durations well within the typical post-feed resting periods, was sufficient to cause >90% mortality. Daily mortality rates escalated dramatically around the time of sporozoite maturation, and infected mosquitoes showed reduced propensity to blood feed. Residual sprays of fungal biopesticides might replace or supplement chemical insecticides for malaria control, particularly in areas of high insecticide resistance.  相似文献   
177.
In recent years, there has been a growing need to understand how salinity affects microbial communities in agricultural soils. Archaeal and bacterial community diversities and structures were investigated by high-throughput sequencing analysis of their 16S rRNA in two arable soils with low electrical conductivity(EC)(2.3 and 2.6 dS m-1) and a saline soil(EC = 17.6 dS m-1). The dominant bacterial phyla in the soils were Proteobacteria(relative abundance(RA) = 46.2%), followe...  相似文献   
178.
Among the brain tumors, glioma is the most common. In general, different biochemical mechanisms, involving nicotinic acetylcholine receptors (nAChRs) and the arachidonic acid cascade are involved in oncogenesis. Although the engagement of the latter in survival and proliferation of rat C6 glioma has been shown, there are practically no data about the presence and the role of nAChRs in C6 cells. In this work we studied the effects of nAChR antagonists, marine snail α-conotoxins and snake α-cobratoxin, on the survival and proliferation of C6 glioma cells. The effects of the lipoxygenase and cyclooxygenase inhibitors either alone or together with α-conotoxins and α-cobratoxin were studied in parallel. It was found that α-conotoxins and α-cobratoxin promoted the proliferation of C6 glioma cells, while nicotine had practically no effect at concentrations below 1 µL/mL. Nordihydroguaiaretic acid, a nonspecific lipoxygenase inhibitor, and baicalein, a 12-lipoxygenase inhibitor, exerted antiproliferative and cytotoxic effects on C6 cells. nAChR inhibitors weaken this effect after 24 h cultivation but produced no effects at longer times. Quantitative real-time polymerase chain reaction showed that mRNA for α4, α7, β2 and β4 subunits of nAChR were expressed in C6 glioma cells. This is the first indication for involvement of nAChRs in mechanisms of glioma cell proliferation.  相似文献   
179.
  1. The Adriatic Sea is one of the Mediterranean areas most heavily impacted by fishing and other human stressors. The northern part of the basin has been certified as an Important Marine Mammal Area because of the regular occurrence of common bottlenose dolphins, Tursiops truncatus.
  2. Boat surveys, totalling 76 days at sea and 10,711 km of navigation, were conducted between April 2018 and October 2019 to assess cetacean abundance within a 3,000-km2 area off Veneto, Italy. Bottlenose dolphins – the only marine mammal species observed – were encountered on 52 days and were tracked for 81 h and 26 min, resulting in 15,066 dorsal fin photographs of high quality and resolution.
  3. Various capture–recapture models were applied on individual photo-identification datasets. Model-based estimates indicate that approximately 600 individuals occurred within the study area during the sampling period in both years. Abundance varied monthly: minimum estimates were obtained in May 2018 (291 individuals; 95% CI 134–630) and May 2019 (121; 95% CI 20–721), whereas maximum estimates were obtained in September 2018 (385; 95% CI 310–477) and October 2019 (494; 95% CI 378–645).
  4. Evidence provided by this study can be used to complement and validate coarse ‘snapshot’ information from recent aerial surveys of the entire Adriatic Sea, and to enforce management action mandated by the European Community (EC) Habitats Directive and Marine Strategy Framework Directive, as well as guiding the EC’s Maritime Spatial Planning.
  相似文献   
180.
Habitats modify the population ecology of species. Here, we show how low water level influences abundance and size of adult anadromous brown trout (Salmo trutta) entering a small, South Norwegian stream for spawning. After smolting, the fish appear chiefly to feed within 10 km of the home stream. In the autumn, South Norwegian streams typically flood because of heavy rainfall, when the anadromous brown trout entered from the sea. Mean annual duration of the upstream migration period was 34 days and ended when the flooding ended and the water temperature dropped to below 4°C. During most of the migration period, on average two trout ascended the river per day. The sexes entered the spawning area concurrently, and the male:female ratio of the anadromous trout was 1.27. No fish entered when the water depth just downstream of the spawning area was below 5 cm, and mean number of fish increased with increasing water depth to ca. 30 cm, but not at higher flows when the ascent gradually decreased. Mean and maximum size of the entering spawners increased with water depth between 5 and 16 cm. Among those that had been to sea, most were recaptured in the home stream, 4% in other streams, but only two of the strays were caught close to spawning time. The present results illustrate that population traits of anadromous brown trout from a small stream differ from those in larger rivers, probably because of selection associated with water flow.  相似文献   
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