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951.
优选前后精子顶体酶活性与IVF受精率相关性的研究 总被引:1,自引:0,他引:1
目的探讨优选处理前和处理后精子顶体酶活性的变化,及与体外受精(IVF)受精率的相关性。方法采用分光光度比色法,对接受IVF治疗的53例不育夫妇男方精液,分别测定优选处理前和处理后精子顶体酶活性,分析其与IVF受精率的相关性。结果优选处理后精子顶体酶活性与优选前比较有显著性差异(P<0.05);达到常规IVF标准并选择常规IVF治疗者,优选后的精子顶体酶活性与IVF受精率有相关性,精子顶体酶活性降低与IVF受精率降低有关。结论精子顶体酶活性与IVF受精率有相关性,并且通过精子顶体酶活性可以预测IVF受精率。 相似文献
952.
953.
954.
August Colenbrander 《Acta ophthalmologica. Supplement》2010,88(2):163-173
This article, based on a report prepared for the International Council of Ophthalmology (ICO) and the International Society for Low Vision Research and Rehabilitation (ISLRR), explores the assessment of various aspects of visual functioning as needed to document the outcomes of vision rehabilitation. Documenting patient abilities and functional vision (how the person functions) is distinct from the measurement of visual functions (how the eye functions) and also from the assessment of quality of life. All three areas are important, but their assessment should not be mixed. Observation of task performance offers the most objective measure of functional vision, but it is time‐consuming and not feasible for many tasks. Where possible, timing and error rates provide an easy score. Patient response questionnaires provide an alternative. They may save time and can cover a wider area, but the responses are subjective and proper scoring presents problems. Simple Likert scoring still predominates but Rasch analysis, needed to provide better result scales, is gaining ground. Selection of questions is another problem. If the range of difficulties does not match the range of patient abilities, and if the difficulties are not distributed evenly, the results are not optimal. This may be an argument to use different outcome questions for different conditions. Generic questionnaires are appropriate for the assessment of generic quality of life, but not for specific rehabilitation outcomes. Different questionnaires are also needed for screening, intake and outcomes. Intake questions must be relevant to actual needs to allow prioritization of rehabilitation goals; the activity inventory presents a prototype. Outcome questions should be targeted at predefined rehabilitation goals. The Appendix cites some promising examples. The Low Vision Intervention Trial (LOVIT) is an example of a properly designed randomized control study, and has demonstrated the remarkable effectiveness of vision rehabilitation. It is hoped that further similar studies will follow. 相似文献
955.
956.
Z. Świderski 《Helminthologia》2007,44(3):130-136
Summary Ultrastructural features of juvenile cestodes (metacestodes) can provide useful characters for phylogenetic and evolutionary
analyses. Until now, however, they have been relatively little utilised (Beveridge 2001, Chervy 2002). The postembryonic development
and structure of fully formed metacestodes were examined in two cyclophyllideans: Taenia parva Baer, 1926 (Taeniidae); and Sobolevitaenia verulamii (Mettrick, 1958) Korniushin, 1972 (Dilepididae). In T. parva, three developmental stages were recognized: (1) an early stage of exogenous budding at the surface of the central vesicle;
(2) a stage of polycephalic cyst development accompanied by segmentation of the growing metacestode strobila and an obvious
decrease in the size of the central vesicle; (3) a fully formed metacestode of the strobilocercus type with 14–24 invaginated
scoleces. The tegument, scolex, subtegumental musculature of the strobilar segments, protonephridial system, calcareous corpuscles
and medullary parenchyma of larvae exhibit general similarity to the same structures in adults at both LM and TEM levels.
The morphogenesis of the metacestode of T. parva is compared with that of polycephalic metacestodes of other Taenia spp. (T. krepkogorski, T. twitchelli and T. endothoracica) and with other asexually multiplying metacestodes (Mesocestoides vogae, hymenolepidids and dilepidids). In S. verulamii, the body of the cysticercoid with invaginated scolex armed with a double crown of rostellar hooks was completely surrounded
by the cercomer, which appears to be separated from the cyst and scolex. The surface of the suckers is covered with a thick
layer of glycocalyx. Five cell types were distinguished in the sections: (1) perikarya of metacestode tegument; (2) glycolgen-storing
parenchymal cells; (3) glandular-type cells with large, electron-dense secretory-like granules; (4) flame cells; and (5) calcareous
corpuscle-forming cells. The surface of the cercomer is covered by elongated microvilli, which evidently differ from characteristic
microtriches covering all other parts of the metacestode surface. The ultrastructure of S. verulamii evidently differs from that of the other dilepidid cestode examined to date, Lateriporus geographicus, the cyst wall of which more resembles cysticercoids of Hymenolepididae than those of Dilepididae. Concluding remarks: Ultrastructural
studies on metacestodes have considerable promise for providing important new characters for phylogenetic analysis. New TEM
data on a great variety of cestode species are urgently needed. Until now, this field has not been exploited in a systematic
fashion. Until more comprehensive studies become available, the current data are not yet amenable to analysis. 相似文献
957.
QT离散度对急危重病人预后的评估 总被引:1,自引:0,他引:1
目的 研究QT离散度对急危重病人预后的预测价值。方法 死亡组 4 7例、疾病组 4 0例和正常组 4 3例。记录 12导联心电图 ,人工测量各导联R -R间期和QT间期 ,计算R -R、QTc、QTd和QTcd。结果 死亡组的R -R、QTc、QTd和QTcd分别为 0 5 6 2± 0 2 2 0ms、0 35 6± 0 0 6 9ms、0 0 5 6± 0 0 33ms和 0 0 79± 0 0 4 6ms ;疾病组的R -R、QTc、QTd和QTcd分别为0 80± 0 134ms、0 4 16± 0 0 3ms、0 0 34± 0 0 14ms和 0 0 39± 0 0 16ms;正常组的R -R、QTc、QTd和QTcd分别为 0 82 5± 0 0 88ms、0 4 0 2± 0 0 3ms、0 0 2 7± 0 0 15ms和 0 0 31± 0 0 15ms。比较死亡组、疾病组和正常组发现 ,死亡组和疾病组的R -R、QTc、QTd和QTcd存在显著差异 (P分别 <0 0 0 1、<0 0 0 2 5、<0 0 0 1和 <0 0 0 1)。死亡组和正常组的R -R、QTc、QTd和QTcd存在显著差异 (P分别 <0 0 0 1、<0 0 0 2 5、<0 0 0 1和 <0 0 0 1)。结论 QTd对急危重病人的预后有一定的预测价值 ;但其它临床应用价值存在局限性 ,有待进一步探索。 相似文献
958.
循证护理在糖尿病皮肤损害临床实践中的应用 总被引:15,自引:0,他引:15
目的 应用循证护理 (EBN) ,探索糖尿病皮肤损害有效干预方法 ,减少残疾及死亡率 ,提高病人生活质量。方法 通过临床评估确定护理诊断 ,查阅文献 ,选择最佳护理证据 ,制定护理干预措施。结果 通过治疗及护理干预 ,2 2例糖尿病患者皮肤损害 ,显效 2 1例 ,有效 1例 ,转科 1例 ,出院时患者无并发症。结论 循证护理应用于临床 ,使传统护理经验走向护理科学发展 ;促进护士主动学习 ,提高护士综合素质 ;优质护理服务于个体化 ;解决患者现存的、潜在的护理问题 ,提高患者生存质量。 相似文献
959.
Patricia H. Arford 《Journal of nursing scholarship》2004,36(3):265-271
PURPOSE: To provide a primer for novice nurse scientists about the increasingly regulated human research environment. ORGANIZING CONSTRUCTS: Federal regulations and international guidelines about protection of human research participants are discussed, with particular attention to institutional review boards for human research. CONCLUSION: Understanding the processes used by institutional review boards to foster ethical human research promotes collaborative interactions and supports compliant research work. 相似文献
960.
目的:探讨乳腺癌改良根治术后自帖式敷料包扎刀口的临床效果。方法:将70例乳腺癌改良根治术患者随机分为两组,对创面不同包扎方式进行对比。结果:自帖式敷帖对术后创面包扎并发症少于传统绷带加压包扎方式。结论:自帖式敷帖包扎乳腺癌改良根治术后创面,能预防切口并发症的发生。 相似文献