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91.
小麦,玉米接种耐氨固氮菌试验初步分析   总被引:3,自引:0,他引:3  
1989—1992年,在广东省部分县市进行了小麦、王米施用耐氨固氮菌大田对比试验,小麦接种耐氨固氮菌后,接菌区小麦的穗氏、有效穗、每穗粒数均比不接菌区明显增加,株高、成穗率、千粒重比对照略有增加,平均每亩比对照增产16.7kg干麦,平均增产率为8.1%。玉米接种耐氨固氮菌后,接菌区玉米的茎粗、收获时的青叶片数、单苞重均比对照区明显增加,秃顶度比对照区明显减小,晒干率:出米率略有增加,平均每亩比对照增产52.8kg玉米,平均增产率为11.89%。  相似文献   
92.
Ultraconserved elements in the human genome likely harbor important biological functions as they are dosage sensitive and are able to direct tissue-specific expression. Because they are under purifying selection, variants in these elements may have a lower frequency in the population but a higher likelihood of association with complex traits. We tested a set of highly constrained SNPs (hcSNPs) distributed genome-wide among ultraconserved and nearly ultraconserved elements for association with seven traits related to reproductive (age at natural menopause, number of children, age at first child, and age at last child) and overall [longevity, body mass index (BMI), and height] fitness. Using up to 24,047 European-American samples from the National Heart, Lung, and Blood Institute Candidate Gene Association Resource (CARe), we observed an excess of associations with BMI and height. In an independent replication panel the most strongly associated SNPs showed an 8.4-fold enrichment of associations at the nominal level, including three variants in previously identified loci and one in a locus (DENND1A) previously shown to be associated with polycystic ovary syndrome. Finally, using 1430 family trios, we showed that the transmissions from heterozygous parents to offspring of the derived alleles of rare (frequency ≤0.5%) hcSNPs are not biased, particularly after adjusting for the rates of genotype missingness and error in the data. The lack of transmission bias ruled out an immediately and strongly deleterious effect due to the rare derived alleles, consistent with the observation that mice homozygous for the deletion of ultraconserved elements showed no overt phenotype. Our study also illustrated the importance of carefully modeling potential technical confounders when analyzing genotype data of rare variants.  相似文献   
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Background

Data on which to base definitive recommendations on the doses and duration of therapy for genotype 3 HCV/HIV-coinfected patients are scarce. We evaluated the efficacy of a lower peginterferon-α 2a dose and a shorter duration of therapy than the current standard of care in genotype 3 HCV/HIV-coinfected patients.

Methods and Findings

Pilot, open-label, single arm clinical trial which involved 58 Caucasian HCV/HIV-coinfected patients who received weekly 135 µg peginterferon-α 2a plus ribavirin 400 mg twice daily during 20 weeks after attaining undetectable viremia. The relationships between baseline patient-related variables, including IL28B genotype, plasma HCV-RNA, ribavirin dose/kg, peginterferon-α 2a and ribavirin levels with virological responses were analyzed.Only 4 patients showed lack of response and 5 patients dropped out due to adverse events related to the study medication. Overall, sustained virologic response (SVR) rates were 58.3% by intention-to-treat and 71.4% by per protocol analysis, respectively. Among patients with rapid virologic response (RVR), SVR and relapses rates were 92.6% and 7.4%, respectively. No relationships were observed between viral responses and ribavirin dose/kg, peginterferon-α 2a concentrations, ribavirin levels or rs129679860 genotype.

Conclusions

Weekly 135 µg pegIFN-α 2a could be as effective as the standard 180 µg dose, with a very low incidence of severe adverse events. A 24-week treatment duration appears to be appropriate in patients achieving RVR, but extending treatment up to just 20 weeks beyond negativization of viremia is associated with a high relapse rate in those patients not achieving RVR. There was no influence of IL28B genotype on the virological responses.

Trial Registration:

ClinicalTrials.gov NCT00553930  相似文献   
95.

Background

This study assessed the short and the long term safety of the 2009 AS03 adjuvanted monovalent pandemic vaccine through an active web-based electronic surveillance. We compared its safety profile to that of the seasonal trivalent inactivated influenza vaccine (TIV) for 2010–2011.

Methodology/Principal Findings

Health care workers (HCW) vaccinated in 2009 with the pandemic vaccine (Arepanrix ® from GSK) or HCW vaccinated in 2010 with the 2010–2011 TIV were invited to participate in a web-based active surveillance of vaccine safety. They completed two surveys the day-8 survey covered the first 7 days post-vaccination and the day-29 survey covered events occurring 8 to 28 days after vaccination. Those who reported a problem were called by a nurse to obtain details. The main outcome was the occurrence of a new health problem or the worsening of an existing health condition that resulted in a medical consultation or work absenteeism. For the pandemic vaccine, a six-month follow-up for the occurrence of serious adverse events (SAE) was conducted. Among the 6242 HCW who received the pandemic vaccine, 440 (7%) reported 468 events compared to 328 of the 7645 HCW (4.3%) who reported 339 events after the seasonal vaccine. The 2009 pandemic vaccine was associated with significantly more local reactions than the 2010–2011 seasonal vaccine (1% vs. 0.03%, p<0.001). Paresthesia was reported by 7 HCW (0.1%) after the pandemic vaccine but by none after the seasonal vaccine. For the pandemic vaccine, no clustering of SAE was found in the 6 month follow-up.

Conclusion

The 2009 pandemic vaccine seems to have a good safety profile, similar to the 2010–2011 TIV, with the exception of local reactions. This surveillance was adequately powered to identify AE associated with an excess risk ≥1 per 1000 vaccinations but is insufficient to detect rare AE.

Trial Registration

ClinicalTrials.gov NCT01289418, NCT01318876  相似文献   
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97.
目的:探讨由肝硬化合并自发性细菌性腹膜炎(spontaneous bacterial peritonitis,SBP)患者血清中IL-10、IL-18及内毒素的水平及其临床意义.方法:采用ELISA方法检测各组血清IL-10、IL-18水平,采用偶氮显色基质法检测内毒素水平.结果:SBP患者血清中IL-10、IL-18及内毒素的水平明显高于正常对照组,P<0.05,SBP患者治疗后血清中IL-10、IL-18及内毒素的水平都明显降低,P<0.05.结论:检测血清中IL-10、IL-18及内毒素在肝硬化患者自发性细菌性腹膜炎中的诊断及预后中具有一定指导意义.  相似文献   
98.
目的:探讨静脉输注高氧液对家猪OLV时肺内分流与氧合的影响.方法:30头健康家猪(25~35 kg)建立OLV模型后,随机分为2组,每组15头,即高氧液组(H组)和对照组(C组),H组动物在单肺通气后经右静内静脉以15 mL·kg-1·h-1的速度恒速输入高氧液,C组动物则以相同的方式和速度输入等量的乳酸林格氏液.分别于双肺通气时、单肺通气30 min、单肺通气60 min时抽取动脉血和混合静脉血做血气分析,并计算肺内分流率(Qs/Qt%),同时记录血流动力学指标.结果:与双肺通气时相比,单肺通气时两组PaO2,SaO2,PvO2和SvO2均显著降低,而Qs/Qt%明显升高(P<0.01).单肺通气30 min以及60 min后,H组的PaO2,SaO2,PvO2和SvO2等指标均显著高于C组(P<0.05),而对于肺内分流率(Qs/Qt%),两组间比较差异无统计学意义.结论:静脉输注高氧液虽然对肺内分流影响不大,却能够明显改善氧合,治疗单肺通气引起的低氧血症.  相似文献   
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在新的课程理念下,教学过程追求的是一种互动、交流、理解和创新。在这个过程中,农村教师应用有限的教学资源来让学生学会学习、学会思考、学会研究、学会创新。  相似文献   
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