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81.
The “high-dose/refuge” strategy is expected to work most effectively when resistance is inherited as a functionally recessive trait and the fitness costs associated with resistance are present. In the present study, a laboratory selected Mythimna separata strain that have evolved >634.5-fold resistance to Vip3Aa19 was used to determine the mode of inheritance. To determine if fitness costs were associated with the resistance, life history parameters (larva stage, pupa stage, pupal weight, adult longevity and fecundity) of resistant (RR), -susceptible (SS) and heterozygous (RS and RS) strains on nontoxic diet were assayed. The LC50 values of RS were significantly higher than that of RS (254.58 μg/g vs. 14.75 μg/g), suggesting that maternal effects or sex linkage were present. The effective dominance h of F1 offspring decreased as concentration increased, suggesting the resistance was functionally dominant at low concentration and recessive at high concentration. The analysis of observed and expected mortality of the progeny from a backcross suggested that more than one locus is involved in conferring Vip3Aa19 resistance. The results showed that significant differences in many life history traits were observed among the four insect genotypes. In short, resistance to Vip3Aa19 in M. separata was inherited as maternal and multigene and the resistance in the strain was associated with significant fitness costs. The results described here provide useful information for understanding resistance evolution and for developing resistance management strategies.  相似文献   
82.
Constipation is a common problem in sows and women during late pregnancy. Dietary fiber has potential in the regulation of intestinal microbiota, thereby promoting intestinal motility and reducing constipation. However, the effects of fibers with different physicochemical properties on intestinal microbe and constipation during late pregnancy have not been fully explored. In this study, a total of 80 sows were randomly allocated to control and one of three dietary fiber treatments from day 85 of gestation to delivery: LIG (lignocellulose), PRS (resistant starch), and KON (konjaku flour). Results showed that the defecation frequency and fecal consistency scores were highest in PRS. PRS and KON significantly increased the level of gut motility regulatory factors, 5-hydroxytryptamine (5-HT), motilin (MTL), and acetylcholinesterase (AChE) in serum. Moreover, PRS and KON promoted the IL-10 level and reduced the TNF-α level in serum. Furthermore, maternal PRS and KON supplementation significantly reduced the number of stillborn piglets. Microbial sequencing analysis showed that PRS and KON increased short-chain fatty acids (SCFAs)-producing genera Bacteroides and Parabacteroides and decreased the abundance of endotoxin-producing bacteria Desulfovibrio and Oscillibacter in feces. Moreover, the relative abundance of Turicibacter and the fecal butyrate concentration in PRS were the highest. Correlation analysis further revealed that the defecation frequency and serum 5-HT were positively correlated with Turicibacter and butyrate. In conclusion, PRS is the best fiber source for promoting gut motility, which was associated with increased levels of 5-HT under specific bacteria Turicibacter and butyrate stimulation, thereby relieving constipation. Our findings provide a reference for dietary fiber selection to improve intestinal motility in late pregnant mothers.  相似文献   
83.
Hodgkin lymphoma (HL)-related hemophagocytic lymphohistiocytosis (HLH) has been reported in the literature; however, there is almost no literature on the factors related to HL triggering HLH.One hundred forty patients with HL were retrospectively analyzed. The incidence of HL-related HLH (we call HL-related HLH as HL-HLH). And all HL-HLH patients in our cohort had HLH as the first manifestation and its clinical characteristics and the role of intrathoracic infection (ITI) in triggering HLH are discussed.The 140 patients with HL mainly included mixed-cellularity classic HL (MCCHL) in 81 (57.9%), nodular sclerosis classic HL (NSCHL) in 36 (25.7%), and lymphacyte-rich classic HL in 14 (10.0%) patients. Of the 137 patients who underwent chest computed tomography scans on admission, 44 had ITI, and most of these ITI were mildly ill and had no respiratory symptoms. Among 140 HL patients, 8 patients from MCCHL were diagnosed as HL-HLH. Among 81 MCCHL patients, 26 patients with ITI had a significantly higher incidence of HL-HLH than those without ITI (26.9% vs 1.8%, P = .002). The median survival time of 8 cases of HL-HLH was only 2 months.When HL patients were first admitted to the hospital, 5.7% had HLH as the first manifestation, and 32.1% had ITI. These ITI can cooperate with HL to trigger HLH, despite their mild illness. The prognosis of HL-HLH was poor.  相似文献   
84.
IOLMaster与接触式A超测量前房深度和眼轴长度的比较研究   总被引:3,自引:2,他引:1  
目的:比较IOLMaster与接触式A超测量中央前房深度和眼轴长度的差异,以评价两者在人工晶状体度数计算参数测量中的准确性.方法:2006-10/2007-01在我院眼科施行白内障超声乳化摘除手术联合人工晶状体植入的患者121例(137眼),分别用IOLMaster与接触式A超于术前测量中央前房深度和眼轴长度.结果:IOLMaster与接触式A超测量中央前房深度分别为(2.94±0.49)mm,(2.58±0.51)mm,配对t检验,两者的差值为(0.36±0.30)mm(P<0.001),差异有显著性,相关系数r=0.823(P<0.001).测量眼轴长度分别为(24.37±3.04)mm,(23.81±2.83)mm,配对t检验,两者差值为(0.56±0.34)mm(P<0.001),差异有显著性,相关系数r=0.996(P<0.001).结论:IOLMaster与接触式A超均可用于前房深度和眼轴长度的测量,两者的相关性好.但基于光学原理的IOLMaster在准确测量眼轴长度和前房深度的同时,简便、快捷、非接触的特点是A超无法比拟的,并可同时测量出其他相关参数.  相似文献   
85.
光动力疗法治疗脉络膜新生血管性疾病的初步临床观察   总被引:5,自引:4,他引:1  
目的:观察使用维替泊芬光动力疗法(photodynamic thera-py,PDT)治疗年龄相关性黄斑变性(age-related maculardegeneration,AMD)、病理性近视和特发性脉络膜新生血管(choroidal neovascularization,CNV)等3种主要的CNV相关疾病的临床效果。方法:对96例(109眼)经临床确诊的上述CNV患者进行PDT治疗,随访1~24(平均9.4)mo。采用最佳矫正视力、荧光素血管造影、吲哚青绿血管造影、光学相干断层成像等指标,观察治疗前后患者的视功能、CNV病灶大小及渗漏情况、以及视网膜水肿变化等,评价PDT治疗CNV的疗效。结果:本组病例包括AMD42例(54眼),病理性近视17例(18眼),特发性CNV患者37例(37眼)。AMD、病理性近视和特发性CNV的平均治疗次数分别为1.2,1.5和1.2次;视力稳定和提高者各组分别为83.3%,83.3%和86.5%;CNV渗漏停止或减少者各组分别为90.7%,83.3%和89.2%:视网膜水肿减轻者各组分别为77.8%,88.9%和86.5%。除3例AMD患者出现眼部严重不良反应外,未发现其他严重不良反应。结论:PDT可有效地改善或稳定AMD、病理性近视和特发性CNV患者的视功能,控制病变进展,近期随访结果安全有效。  相似文献   
86.
经瞳孔温热疗法治疗隐匿性脉络膜新生血管   总被引:6,自引:6,他引:0  
目的:对经瞳孔温热疗法(transpupillary thermotherapy,TTT)治疗隐匿性脉络膜新生血管(occult choroidal neovas-cularization,OCNV)的效果进行评价。方法:眼底荧光素血管造影(fundus fluorescence angiog-raphy,FFA)及吲哚青绿血管造影(indocyanine green angiography,ICGA)检查后确诊为单眼或双眼OCNV患者35例43眼,使用Iris810nm半导体激光进行TTT治疗,选择1.2,2.0及3.0mm直径的光斑,以光斑大小能够完全覆盖FFA及ICGA所显示的病变范围为宜,长脉冲模式,能量80~300mW,照射时间60s。结果:TTT治疗后,18/43眼(42%)视力提高,23/43眼(53%)视力无变化,2/43眼(5%)视力下降;20/43眼(47%)CNV渗漏完全停止,18/43眼(42%)渗漏明显减少,4/43眼(9%)渗漏无改变,1/43眼(2%)渗漏扩大。结论:TTT治疗OCNV效果较好,其适宜的参数及治疗机制还需进一步探讨。  相似文献   
87.
This study was conducted to estimate the risk of human cancer from the inhalation of formaldehyde in different indoor environments in Guiyang City in China. Offices had the highest mean formaldehyde concentration (0.11 mg/m(3)) and classrooms had the lowest mean formaldehyde concentration (0.04 mg/m(3)). The cancer risk levels in different indoor environments ranged from 6.96 x 10(-6 )to 2.48 x 10(-4) and were greater than the acceptable cancer risk 1 x 10(-6). High human formaldehyde risks imply a critical influence on human health in Guiyang City. The highest cancer risk values occurred in bedrooms (ranging from 1.87 in 10,000 to 2.48 in 10,000). For office workers, offices were the highest risk environment after bedrooms where formaldehyde concentration levels were identified. Students were the most sensitive population, and the highest priority should be given to protecting their health in indoor environments. Regulations and standards for low emission materials and public education in relation to indoor pollution are highly recommended in China to protect human health.  相似文献   
88.
Thymic epithelial tumors (TETs) are one of the rarest adult malignancies in the anterior mediastinum. Thymic carcinomas (TCs) are less prevalent among TETs, but they are more clinically aggressive. Immunotherapy has emerged as a promising therapeutic approach for refractory TETs, even though chemotherapy remains the conventional treatment for the advanced disease. However, limited attention has been paid to the features of the tumor microenvironment (TME) which might provide clinically relevant information and guide treatment regimen design. Especially, to date, there have been only a few studies focusing on the differences between the TME and genomic features preserved by TETs and TCs. We analyzed the TME and genomic characteristics of TETs using RNA sequencing and whole-exome sequencing, finding that distinct characteristics of TME in different pathogenic subtypes of TETs. According to those findings, we found that thymic carcinomas had significantly lower expression of HMGB1, a pro-inflammatory cytokine-related gene, than thymomas, and low HMGB1 expression was linked to a poor prognosis. Additionally, higher mutation burdens were significantly associated with the later stage and more advanced pathological types. Thymoma patients with lower mutation burdens tended to relapse within 3 years. In summary, different characteristics of TME and genomic features between thymoma and thymic carcinoma were associated with clinical outcomes of TETs and presented promisingly predictive value for efficacy and toxicity of immunotherapy.  相似文献   
89.
本文探讨了化妆品生产过程中细菌污染的主要原因,并对提高化妆品生产的卫生质量管理提出了针对性建议。  相似文献   
90.
Multi-stage heat treatment is an important method to improve the mechanical properties of Al-Si-Cu-Mg aluminum alloys. In this paper, the multi-stage heat treatment was carried out for the Cd-free and Cd-containing alloys. The experimental results show that the addition of Cd promoted the precipitation of Q″ and θ″, which led to the formation of a large number of fine, dispersed precipitates and a higher yield strength (YS) and ultimate tensile strength (UTS) for the Cd-containing alloys. The addition of Cd also altered the optimal heat treatment parameters. For the Cd-free alloys, the Cu-rich phase fully dissolved after three-stage heat treatment, and the YS and UTS of the three-stage heat-treated alloys were higher than their two-stage heat-treated counterparts. For the Cd-containing alloys, the three-stage heat treatment led to the precipitation of Cd-rich low melting point phases, caused defects, and reduced the mechanical properties of the alloy. The size and volume fractions of the precipitates were significantly less than those of the alloys after two-stage heat treatment and the strength of the alloys decreased. Therefore, the solution time should be strictly controlled for Cd-containing Al-Si-Cu-Mg alloys.  相似文献   
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