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41.
Tuberculosis (Tb) caused by Mycobacterium bovis is a worldwide threat to livestock and humans. One control strategy is to breed livestock that are more resistant to Mycobacterium bovis. In a 3-year heritability study 6 farmed red deer stags were selected from 39 on the basis of their differing responses to experimental challenge via the tonsillar sac with approximately 500 CFU of M. bovis. Two stags remained uninfected, two were moderately affected, and two developed serious spreading Tb. Seventy offspring, bred from these six stags by artificial insemination using stored semen, were similarly challenged with M. bovis. The offspring showed patterns of response to M. bovis challenge similar to those of their sires, providing evidence for a strong genetic basis to resistance to Tb, with an estimated heritability of 0.48 (standard error, 0.096; P < 0. 01). This is the first time the heritability of Tb resistance in domestic livestock has been measured. The breeding of selection lines of resistant and susceptible deer will provide an ideal model to study the mechanisms of Tb resistance in a ruminant and could provide an additional strategy for reducing the number and severity of outbreaks of Tb in farmed deer herds. Laboratory studies to identify genetic and immunological markers for resistance to Tb are under way. Preliminary studies showed no associations between NRAMP or DRB genes and resistance to Tb in deer. Patterns of immune responses seen in resistant animals suggest that both innate and acquired pathways of immunity are necessary to produce the resistant phenotype.  相似文献   
42.
Diphosphoryl lipid A from the lipopolysaccharide (LPS) of Rhodobacter sphaeroides (Rs-DPLA) has been demonstrated to block in mice and guinea pigs the increase in the serum tumor necrosis factor (TNF) response induced by highly purified deep rough chemotype LPS from Escherichia coli D31m4 (ReLPS). The present study was designed to determine the role of corticosterone induction by Rs-DPLA and its effect on TNF regulation and survival in lethal endotoxin shock models and to evaluate the ability of Rs-DPLA to induce endotoxin tolerance. Administration of a 100-fold excess of Rs-DPLA 1 h prior to ReLPS administration inhibited the characteristic peak in serum TNF levels induced by LPS. Inhibition was apparent in normal and D-galactosamine (GalN)-sensitized mice and occurred at the pretranslational level, as splenic TNF and interleukin-1 beta mRNAs were present in lower amounts in LPS-stimulated mice pretreated with Rs-DPLA. Consistent with its effects in reducing serum TNF levels, Rs-DPLA pretreatment protected GalN-sensitized mice from a lethal ReLPS challenge. In contrast, Rs-DPLA did not inhibit the increase in the serum TNF response or protect against a lethal ReLPS challenge in parallel experiments with adrenalectomized (Adrex) mice, for which the 50% lethal dose of ReLPS was comparable to that for GalN-sensitized mice. Furthermore, Rs-DPLA appeared to prime Adrex animals and increase the magnitude of the serum TNF response to a suboptimal LPS stimulus. Priming by Rs-DPLA, however, was not observed in normal or GalN-sensitized mice. Although Rs-DPLA by itself was nontoxic and unable to elevate serum TNF levels in any of the models investigated, it did induce a significant increase in the serum corticosterone response and was capable of inducing endotoxin tolerance in normal mice. The inability of Rs-DPLA to protect Adrex mice from a lethal ReLPS stimulus or to inhibit the increase in the serum TNF response suggests that the protective effect of Rs-DPLA in normal or GalN-sensitized animals occurs through corticosterone induction. These results support the concept that endogenous glucocorticoids can modulate the endotoxic effects of LPS by inhibiting the synthesis of inflammatory cytokines.  相似文献   
43.
Interventions from randomised controlled trials can only be replicated if they are reported in sufficient detail. The results of trials can only be confidently interpreted if the delivery of the intervention was systematic and the protocol adhered to. We systematically reviewed trials of anaesthetic interventions published in 12 journals from January 2016 to September 2019. We assessed the detail with which interventions were reported, using the Consolidated Standards of Reporting Trials statement for non-pharmacological treatments. We analysed 162 interventions reported by 78 trials in 18,675 participants. Detail sufficiently precise to replicate the intervention was reported for 111 (69%) interventions. Intervention standardisation was reported for 135 (83%) out of the 162 interventions, and protocol adherence was reported for 20 (12%) interventions. Sixty (77%) out of the 78 trials reported the administrative context in which interventions were delivered and 36 (46%) trials detailed the expertise of the practitioners. We conclude that bespoke reporting tools should be developed for anaesthetic interventions and interventions in other areas such as critical care.  相似文献   
44.
目的探讨虾青素能否防治去卵巢糖尿病大鼠的骨质流失以及可能的机制。方法 3月龄雌性SD大鼠分为3组(每组6只):对照组CON(假手术),模型组OVX/T1DM(去卵巢糖尿病大鼠),药物组OVX/T1DM-ASX(去卵巢糖尿病大鼠,给予虾青素100 mg/(kg·d)。结果连续治疗60 d后,与OVX/T1DM组相比,OVX/T1DM-ASX组骨密度(BMD)明显升高(P0.01),血清I型胶原蛋白(CTX-1)、骨钙素、I型前胶原蛋白n端前肽(PINP)、抗酒石酸磷酸酶5b(TRACP 5b)水平均显著升高(P0.01)。虾青素治疗能抑制去卵巢糖尿病大鼠骨组织形态学的改变,减少骨髓脂肪细胞增加,提高OPG/RANKL的比值。结论虾青素对绝经后糖尿病骨质流失有保护作用,这种作用与调控OPG/RANKL轴有关。  相似文献   
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Exceptional precautionary measures have been adopted to stop the transmission and control of COVID-19 through the world and Pakistan is facing lockdown in this scenario. Public loyalty to precautionary measures is affected by their knowledge, attitude, risk factors and practices (KAP) towards COVID-19. The present study was conducted among the Pakistani residents to observe the knowledge, attitude, practices and risk factors towards COVID-19 outbreak in Pakistan. A questionnaire was designed, and a cross-sectional survey was conducted among participants of the study area. Participants were asked the questions regarding knowledge, attitude, practices and risk factors towards COVID-19. Data were analyzed by SPSS and t/F test and correlation was applied among the knowledge, attitude, risk factors and practices. A total of 1060 questionnaires were received. 1004 were included while 56 were excluded. The highest representation was from Punjab province (65.6%), female (63%) and age group of 21–30 years (62.1%). Most participants were single (85%), Muslim (99.4%), Urdu speaking (45.6%) and were graduates (51.5%). Most of the participants were students (52.9%) and were from economically middle-class families (40.8%). The knowledge was positively correlated with attitude and practices whereas negatively correlated with risk factors (P?<?0.05). The attitude was negatively correlated with risk factor and positively correlated with practices. The risk factors and practices were positively correlated with each other. Health education program to improve the COVID-19 knowledge, attitude, practices and risk factors should be initiated to combat current health challenge.

  相似文献   
48.
目的 分析放射工作者外周血象、淋巴细胞微核及染色体畸变情况,为放射工作者职业防护和健康监测提供依据。方法 对2015年、2017年和2019年连续3次接受健康检查的127名放射工作者进行淋巴细胞微核、染色体及血象分析,将其设为放射组。另外选取133名无射线接触史的医务人员设为对照组;结果 放射组中淋巴细胞微核率和染色体畸变率高于对照组,白细胞和血小板计数低于对照组,均具有统计学意义(P < 0.05)。127名放射工作者外周血白细胞总数随着接触电离辐射时间的增长逐渐降低,染色体畸变率逐渐增加,均具有统计学意义(P < 0.05)。损害工龄大于20年的放射工作者染色体畸变率高于低工龄组,不同损害工龄之间比较无统计学意义(P > 0.05)。核医学与介入治疗工种染色体畸变率高于其他工种,具有统计学意义(P < 0.05)。结论 长时间接触低剂量电离辐射可使放射工作者白细胞总数降低和淋巴细胞染色体畸变率增加,应加强放射工作者防护措施以备降低电离辐射损伤程度,特别要加强核医学和介入治疗放射工作人员的职业防护。  相似文献   
49.
Genetic effects of chronic treatment with cathinone in mice   总被引:1,自引:0,他引:1  
The mutagenicity of (—)-cathinone has been evaluated inthe germ cells of male albino mice using a dominant lethal test.An aqueous solution of cathinone was administered orally atdoses of 5, 20 or 40 mg/kg body wt, respectively to three differentgroups of male mice for a period of six weeks. After treatment,each male was allowed to mate with two different groups of threefemales each, on two consecutive weeks. These females were necropsiedon the 17th day after mating. The number of implants in eachfemale and the ratio of live and dead embryos was determined.The results of this study showed that treatment of male miceover a period of 6 weeks produced a dose-dependent reductionin fertility with total sterility at a dose of 40 mg/kg bodywt. Cathinone also induced dose-dependent post-implantationloss during the first week following treatment. However, nodominant lethality was detected during the second week of mating.  相似文献   
50.
彩色多普勒超声心动图诊断肺心病的临床价值   总被引:1,自引:1,他引:0  
目的:阐述彩色多普勒超声心动图(CDE)诊断肺心病的临床价值。方法:通过CDE对临床上拟诊的肺心病患者进行肺动脉高压(PH)定性、定量的诊断、并观测由PH继发引起心脏在CDE上的异常改变。结果:CDE测定PH44例(88%),其肺动脉收缩压(SPAP)>36mmHg,6例(32mmHg≤SPAP<36mmHg,确诊CPM的临床符合率665(50/76)。结论作为无创性诊技术,CDE估测PH或诊断CPM准确简便,重复性强,对于指导临床治疗意义重大。  相似文献   
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