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101.
在广泛文献检索基础上,对马蔺的成分、药理(主要表现为抗癌活性)及临床应用(种子、根、花、叶等)进行了概述,为其深入开发利用提供参考。  相似文献   
102.
新疆南部棉区黄萎病菌种群致病性分化及变异   总被引:3,自引:0,他引:3  
 采用鉴别寄主法和特异性引物PCR检测技术对采自新疆南部(南疆)棉区的36个棉花黄萎病菌菌系进行检测,以期明确其病原种群致病性分化及变异情况。鉴别寄主法测定结果显示:供试菌系中致病性强、中、弱的菌系分别为27个、4个和5个,各占75.0%,11.1%和13.9%。特异性引物(ND1/ND2和D1/D2)PCR检测结果显示,供试36个菌系中落叶型菌系12个,占33.3%;非落叶型菌系24个,占66.7%。经统计,落叶型菌系的致病力明显高于非落叶型菌系,其平均病指分别为43.8和31.8。接种试验证明,无论落叶型菌系和非落叶型菌系,接种后都可产生落叶症状,但落叶的情况有明显差别,落叶症状的轻重不仅与菌系的致病类型有关,还与棉花品种的抗病性密切相关。  相似文献   
103.
Mortality of sows is a major problem for pig production worldwide. In this study, we used hierarchical multivariable logistic analyses to investigate different risk factors for mortality at the sow and herd level in herds with group-housed pregnant sows. Data included 3652 pregnant and 1266 lactating sows from 34 sow herds. A clinical examination for 16 clinical signs was carried out for each sow, and information about 16 herd related factors was obtained by interviews. Farm records were used to obtain information about whether or not sows died suddenly or were euthanized within 3 months after the clinical examination. Factors increasing the risk of sow mortality in the gestation unit were solid pen floors (OR = 1.87), presence of vulva bites (OR = 1.73) and unwillingness to stand when approached (OR = 1.62). Factors increasing the risk of sow mortality in the lactation unit were pale vulva color (OR = 12.69), body leanness (OR = 4.11), and presence of shoulder ulcers (OR = 2.89). The estimated between herd variation was small. Thus, the findings for the sow level variables may be generally applicable for sows in herds with group housed systems.  相似文献   
104.
Sepsis, the systemic inflammatory response to infection, represents the major cause of death in critically ill veterinary patients. Whereas important advances in our understanding of the pathophysiology of this syndrome have been made, much remains to be elucidated. There is general agreement on the key interaction between pathogen-associated molecular patterns and cells of the innate immune system, and the amplification of the host response generated by pro-inflammatory cytokines. More recently, the concept of immunoparalysis in sepsis has also been advanced, together with an increasing recognition of the interplay between regulatory T cells and the innate immune response. However, the heterogeneous nature of this syndrome and the difficulty of modeling it in vitro or in vivo has both frustrated the advancement of new therapies and emphasized the continuing importance of patient-based clinical research in this area of human and veterinary medicine.  相似文献   
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为了解潮霉素B预混剂临床驱除绦虫线虫的有效性和给药时间的合理性,依据兽药临床试验规范,试验选择了蠕虫自然感染皖西麻黄鸡824只,按要求随机分为3组,分别为潮霉素B预混剂治疗组284只,芬苯哒唑粉对照药物组284只,不治疗的感染对照组256只,试验周期根据临床治疗效果确定。结果显示,潮霉素B预混剂,推荐剂量10 mg/kg混饲,连续饲喂21 d,对鸡蛔虫和绦虫的粗计驱虫率分别为63%和26%,表现明显的驱除蛔虫作用(P0.05),连续饲喂42 d,对鸡蛔虫和绦虫的粗计驱虫率分别为100%和-13%,驱蛔虫效果极显著(P0.01);对照药物芬苯哒唑粉,50 mg/kg混饲,连续饲喂6 d,对鸡蛔虫和绦虫的粗计驱虫率分别为100%和44%,同样具有极显著的驱除蛔虫作用(P0.01),本试验中2种药物的驱蛔虫效果相当,对绦虫的驱除作用不明显(P0.05)。潮霉素B预混剂10 mg/kg混饲,连续饲喂42 d,可以驱净鸡蛔虫的感染,但对鸡绦虫感染无明显的驱除作用。  相似文献   
110.
Abstracts should be clear, transparent, and sufficiently detailed to convey the main elements of the study, including the question, primary outcome measure, study design, and main conclusions.6 Abstracts may influence whether busy clinicians will read the full article, and, if a study is not open access, practitioners may need to make clinical decisions from abstracts only. Consider also that, with new technologies and means of accessing information, the abstract content alone may serve as the

Methods

The Methods section provides a detailed report of the what and the how of the described research process. However, in order to maximize reader comprehension and to permit repeatability of research, several methodological aspects need to be transparently reported (Table 2). Again, by clearly defining the type of study design, investigators can then refer to the appropriate reporting guideline and supporting materials for guidance. Even where aspects of trial design may have been suboptimal, use

Blinding

In research, there is often the need to blind (ie, to make people unaware) investigators (personnel and outcome assessors) and/or participants for several reasons (Table 4). When reporting any type of study, it should be made clear to readers which individuals were blinded, and to what. The use of terminology such as single, double, and triple blinding should be avoided because such terms can be variably interpreted and fail to explicitly explain blinding procedures.29 The following categories

Participant Flow

It is highly recommended in all study designs to depict the flow of participants with a flow diagram (Fig. 1).6, 8 Information required to complete a flow diagram for a RCT, for example, includes the number of participants evaluated for potential enrollment into the trial and the number excluded at this stage because they either did not meet the inclusion criteria or declined to participate. For each intervention group it also requires the numbers of participants which were randomly assigned,

Discussion

The discussion reports the results of the study in the context of existing evidence.6, 8, 9 The investigators should cautiously interpret the results considering the objectives, limitations, multiplicity of analyses, results from similar studies, and other relevant evidence. In brief, the investigators should (1) summarize the results considering the study objectives; (2) discuss the limitations of the study, addressing sources of potential bias (both direction and magnitude), imprecision, and

Summary

This article discusses aspects of research reporting. Other than purely literary reporting, there is a multitude of other types of reporting deficiencies that increase research waste (Box 1). Awareness of such problems is the first step toward improvement.
  相似文献   
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