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991.
Kyra Megan Jennings Laila Curtis John Harold Burford Sarah Louise Freeman 《BMC veterinary research》2014,10(Z1):S2
Background
Large colon impactions are a common cause of colic in the horse. There are no scientific reports on the clinical presentation, diagnostic tests and treatments used in first opinion practice for large colon impaction cases. The aim of this study was to describe the presentation, diagnostic approach and treatment at the primary assessment of horses with large colon impactions.Methods
Data were collected prospectively from veterinary practitioners on the primary assessment of equine colic cases over a 12 month period. Inclusion criteria were a diagnosis of primary large colon impaction and positive findings on rectal examination. Data recorded for each case included history, signalment, clinical and diagnostic findings, treatment on primary assessment and final case outcome. Case outcomes were categorised into three groups: simple medical (resolved with single treatment), complicated medical (resolved with multiple medical treatments) and critical (required surgery, were euthanased or died). Univariable analysis using one-way ANOVA and Tukey’s post-hoc test, Kruskal Wallis with Dunn’s post-hoc test and Chi squared analysis were used to compare between different outcome categories.Results
1032 colic cases were submitted by veterinary practitioners: 120 cases met the inclusion criteria for large colon impaction. Fifty three percent of cases were categorised as simple medical, 36.6% as complicated medical, and 9.2% as critical. Most cases (42.1%) occurred during the winter. Fifty nine percent of horses had had a recent change in management, 43% of horses were not ridden, and 12.5% had a recent / current musculoskeletal injury. Mean heart rate was 43bpm (range 26-88) and most cases showed mild signs of pain (67.5%) and reduced gut sounds (76%). Heart rate was significantly increased and gut sounds significantly decreased in critical compared to simple medical cases (p<0.05). Fifty different treatment combinations were used, with NSAIDs (93%) and oral fluids (71%) being administered most often.Conclusions
Large colon impactions typically presented with mild signs of colic; heart rate and gut sounds were the most useful parameters to distinguish between simple and critical cases at the primary assessment. The findings of seasonal incidence and associated management factors are consistent with other studies. Veterinary practitioners currently use a wide range of different treatment combinations for large colon impactions.992.
Dongliang Li Xueying Yang Zheng Zhang Zixin Wang Xiao Qi Yuhua Ruan Yunhua Zhou Chunrong Li Fengji Luo Joseph T. F. Lau 《PloS one》2016,11(1)
Background
The HIV-epidemic among MSM in China has worsened. In this key population, prevalence of HSV-2 and syphilis infection and co-infection with HIV is high.Methods
A longitudinal study was conducted (n = 962) in Beijing, China, with three overlapping cohorts (n = 857, 757 and 760) consisting of MSM that were free from pairs of infections of concern (i.e. HIV-HSV-2, HIV-syphilis, HSV-2-syphilis) at baseline to estimate incidence of HIV, HSV-2, syphilis, and those of co-infection.Results
The incidence of HIV, HSV-2 and syphilis in the overall cohort was 3.90 (95% CI = 2.37, 5.43), 7.87 (95% CI = 5.74, 10.00) and 6.06 (95% CI = 4.18, 7.94) cases per 100 person-years (PYs), respectively. The incidence of HIV-HSV-2, HIV-Syphilis and HSV-2-Syphilis co-infections was 0.30 (95% CI = 0.29, 0.88), 1.02 (95% CI = 0.13, 2.17) and 1.41 (95% CI: 0.04, 2.78) cases per 100 PYs, respectively, in the three sub-cohorts constructed for this study.Conclusions
The incidence of HIV, HSV-2 and syphilis was very high and those of their co-infections were relatively high. Such co-infections have negative impacts on the HIV/STI epidemics. Prevention practices need to take such co-infections into account. 相似文献993.
Choosing appropriate approaches is a key to successfully using biological control measures to accelerate the recovery of eutrophic waterbodies. In this study, we used three biomanipulation approaches—including introducing filter-feeding bivalves, stocking planktivorous fish, replanting submerged macrophytes—as well as an approach that combined all three of these methods in order to investigate their effects on water quality and plankton communities within simulation experiment systems. The experimental results showed that only stocking filter-feeding bivalves or fish could not significantly control the total algal biomass and water nutrient concentrations compared to those of the controls. The cladoceran biomasses were reduced under the treatments of stocking filter-feeding bivalves or fish. However, replanting macrophytes and a combined biological restoration approach could significantly reduce the algal biomass and the nutrient content, and both of these methods increased cladoceran biomass. The results of factor analysis of ten environmental parameters suggested that a combined biological restoration treatment was the most effective at controlling the algal biomass and reducing the nutrient content. In conclusion, combination of biological restoration measures was the best treatment out of the three treatments that were tested, and we suggest that more whole-lake scale experiments are needed. Additionally, designing a combined approach should not be a simple superposition of individual measures, but the measures should be complementary to each other. 相似文献
994.
995.
Carlotta Giromini Raffaella Rebucci Eleonora Fusi Luciana Rossi Francesca Saccone Antonella Baldi 《Cell biology and toxicology》2016,32(3):249-258
This study aimed to investigate the in vitro damage induced by ochratoxin A (OTA) in BME-UV1 and MDCK epithelial cells. Both cells lines were treated with OTA (0 up to 10 μg/mL), and cell viability (MTT assay), membrane stability (lactate dehydrogenase (LDH) release assay) and apoptotic cell rate (Tunel assay) were investigated. Further, the effect of the incubation with OTA has been evaluated at DNA level by the determination of DNA integrity, by the quantification of DNA adduct formation (8-hydroxy-2′-deoxyguanosine (8-OHdG)) and by the assessment of the global DNA methylation status (5-methyl-cytosine (5-mC)). The obtained results showed that after 24 h of OTA treatment, BME-UV1 cell viability was reduced in a dose-dependent way. OTA significantly (P?<?0.05) increased LDH release in BME-UV1 cells at all concentrations tested. OTA (1.25 μg/mL) induced 35 % LDH release in MDCK cells (P?<?0.05). A significant (P?<?0.05) change in percentages of apoptotic BME-UV1 (10?±?0.86) and MDCK (25?±?0.88) cells was calculated when the cells were co-incubated with OTA. The level of 8-OHdG adduct formation was significantly (P?<?0.05) increased in BME-UV1 cells treated with 1.25 μg/mL of OTA. The results of the present study suggest that a different mechanism of action may occur in these cell lines. 相似文献
996.
Yong Chao Lu Hui Chen Kin Lam Fok Lai Ling Tsang Mei Kuen Yu Xiao Hu Zhang Jing Chen Xiaohua Jiang Yiu Wa Chung Alvin Chun Hang Ma Anskar Yu Hung Leung He Feng Huang Hsiao Chang Chan 《Cell research》2012,22(10):1453-1466
Although HCO3− is known to be required for early embryo development, its exact role remains elusive. Here we report that HCO3− acts as an environmental cue in regulating miR-125b expression through CFTR-mediated influx during preimplantation embryo development. The results show that the effect of HCO3− on preimplantation embryo development can be suppressed by interfering the function of a HCO3−-conducting channel, CFTR, by a specific inhibitor or gene knockout. Removal of extracellular HCO3− or inhibition of CFTR reduces miR-125b expression in 2 cell-stage mouse embryos. Knockdown of miR-125b mimics the effect of HCO3− removal and CFTR inhibition, while injection of miR-125b precursor reverses it. Downregulation of miR-125b upregulates p53 cascade in both human and mouse embryos. The activation of miR-125b is shown to be mediated by sAC/PKA-dependent nuclear shuttling of NF-κB. These results have revealed a critical role of CFTR in signal transduction linking the environmental HCO3− to activation of miR-125b during preimplantation embryo development and indicated the importance of ion channels in regulation of miRNAs. 相似文献
997.
Xishan Lu Yi Shi Feng Gao Haixia Xiao Ming Wang Jianxun Qi George F. Gao 《Journal of virology》2012,86(23):12861-12870
With a new serotype (H17) of hemagglutinin (HA) recently being discovered, there are now 17 serotypes (H1 to H17) of influenza A viruses in total. It is believed that HA is initially expressed as a precursor of HA0 and then cleaved into HA1 and HA2, forming a disulfide bond-linked complex, for its full function. Structural data show that a loop structure exists in the cleavage site between HA1 and HA2, and this flexible loop is crucial for the efficient cleavage of HA0. Here, the crystal structures of H16 (a low-pathogenicity avian influenza virus) in their HA0 form (H16HA0) have been solved at 1.7-Å and 2.0-Å resolutions. To our surprise, an α-helix element in the cleavage site which inserts into the negatively charged cavity with the key residue R329 hidden behind the helix was observed. In vitro trypsin cleavage experiments demonstrated inefficient cleavage of H16HA0 under both neutral and low-pH conditions. The results provide new insights into influenza A virus pathogenicity; both the relatively stable α-helix structure in the flexible cleavage loop and inaccessibility of the cleavage site likely contribute to the low pathogenicity of avian influenza A virus. Furthermore, compared to all of the HAs whose structures have been solved, H16 is a good reference for assigning the HA subtypes into two groups on the basis of the three-dimensional structure, which is consistent with the phylogenetic grouping. We conclude that in light of the current H16HA0 structure, the natural α-helix element might provide a new opportunity for influenza virus inhibitor design. 相似文献
998.
睫状神经营养因子对体外培养骨骼肌细胞的促增殖效应 总被引:1,自引:1,他引:1
邓小华 《中国应用生理学杂志》2000,16(1):59-63
目的 :探讨睫状神经营养因子 (CNTF)对骨骼肌细胞的直接营养作用 ,从而为神经肌肉系统损伤和退行性病变的治疗提供新的思路。结果 :CNTF可以促进体外培养的L6 TG肌母细胞和新生SD大鼠原代骨骼肌细胞增殖。结论 :CNTF对体外骨骼肌细胞具有营养作用。CNTF的神经和肌肉双重营养性能使其可能在神经肌肉损伤和退行性病变的治疗上发挥重要作用。 相似文献
999.
1000.