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土壤侵蚀过程的降雨能量组成

水土保持科技情报 1990年第1期8卷 36-38,59页

作者： Prasad S.n. M.j.M.Rōmkens 周森林

本文讨论了一个正在进行的研究结果.在研究过程中,连续机制原理被用于描述雨滴冲击的土壤侵蚀.这个过程由几个明显的物理现象所组成.例如,在高冲击压力下,由于孔隙壁的崩溃、孔隙的压实,拉应力波形成的拉伸裂缝,土壤的分离以及射流(辐向... 详细信息

本文讨论了一个正在进行的研究结果.在研究过程中,连续机制原理被用于描述雨滴冲击的土壤侵蚀.这个过程由几个明显的物理现象所组成.例如,在高冲击压力下,由于孔隙壁的崩溃、孔隙的压实,拉应力波形成的拉伸裂缝,土壤的分离以及射流(辐向流)引起剪切侵蚀等.因此,给这些于过程的能量平衡方法做一个定量分析是特别有用的.为此目的,一个能量侵蚀速率函数,在通用能量守恒方程中被引入,并被证明是依赖于控制这些子过程的参数.特别对冲击过程进行了详细地讨论,如由于冲击,引起冲击波的传播以及克服颗粒粘结所需能量等等.

关键词：土壤侵蚀降雨能量

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苜蓿和玉米叶比重的昼夜变化

中国畜牧兽医 1974年第6期 32-35页

作者： n.j. Chatterton D.R. Lee W.E. Hungerford 郭博

植物的许多生理特性都与叶比重(叶比重=单位干重/单位叶面积)有关。许多研究结果表明,水稻、苜蓿、大豆和燕麦的叶比重与二氧化碳净交换为正相关。赫斯基思发现,单位绿叶重和光合作用之间没有关系。据达尔克报道,叶比重低的苜蓿和白三叶... 详细信息

植物的许多生理特性都与叶比重(叶比重=单位干重/单位叶面积)有关。许多研究结果表明,水稻、苜蓿、大豆和燕麦的叶比重与二氧化碳净交换为正相关。赫斯基思发现,单位绿叶重和光合作用之间没有关系。据达尔克报道,叶比重低的苜蓿和白三叶(Trifolium

关键词：非结构二氧化碳 CO2 工业气体光合作用效率光合效率昼夜变化玉米叶

早产儿视网膜病变3期治疗后和阈下3期自然转归的比较:对3个月和3年病变活动性、屈光力和解剖学变化的研究

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世界核心医学期刊文摘（眼科学分册） 2005年第6期1卷 23-24页

作者： Sahni j. Subhedar n.V. Clark D. 王永强 Department of Ophthalmology Walton Hospital Rice Lane Liverpool L9 IAE United Kingdom

Aim: To compare the visual acuity (VA), spherical equivalent refractive error, motility, and anatomical outcomes in children with treated regressed threshold stage3 retinopathy of prematurity (ROP) and those with spontaneously regressed subthreshold stage3 ROP. Method: 6 month and 3 year data collected from infants examined between 1989 and 1999 with regressed stage3 ROP, with or without treatment were retrospectively reviewed. Results: 85 infants were included in this study. 40 eyes received cryotherapy, 81 eyes laser photocoagulation, and 34 eyes had spontaneously regressed subthreshold stage3 ROP. Grating acuity score ≥ 2 cycles/degree (c/d) at 6 months was predictive of optotype acuity ≥ 6/9 in 69% of eyes and a score nths was predictive of acuity n 88% of eyes. Eyes with subthreshold stage3 ROP were twice as likely to haveVA of 6/9 or better at 36 months than the treated eyes. The mean spherical equivalent refractive error at 36 months was-6.5 dioptres (D) (-21.5D to + 1.38D) in cryotherapy treated eyes,-2.4D (-13D to + 4D) in the laser group, and-0.22D (-9D to + 2.25D) in the subthreshold group. Eyes within the treated groups were more myopic than the eyes within the spontaneously regressed group (P=0.005). At 36 months, 42 out of the 85 infants (that is, 49% ) had strabismus (44% in the cryotherapy group, 26% in the laser group, and 25% in the subthreshold group). There was a statistically significant association between the presence of strabismus and anisometropia (P=0.016) and strabismus and intraventricular haemorrhage (IVH) (P=0.005). There was a statistically significant difference in the incidence of strabismus between mild and moderate and severe grade IVH (P=0.01). Eight out of 40 eyes in the cryotherapy group and six out of the 81 eyes in the laser group developed macular ectopia. none of the eyes in the spontaneously regressed group had macular dragging. Conclusions: In this study, the grating acuity at 6 months was a good pred

关键词：病变活动屈光力自然转归激光治疗组黄斑异位等量球镜激光光凝术近视程度屈光不正屈光参差

充血性心衰患者血管源性细胞因子循环水平的预后意义

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世界核心医学期刊文摘（心脏病学分册） 2006年第1期2卷 28-29页

作者： Lamblin n. Susen S. Dagorn j. C. Bauters 宁宁 Dr. Hpital Cardiologique CHRU de Lille Boul. Prof. Leclercq 59037 Lille Cedex France

Background: Recent experimental studies have suggested that the angiogenic cytokines hepatocyte growth factor(HGF) and vascular endothelial growth factor(VEGF) may play a role in the pathogenesis of congestive heart failure(CHF). The aim of the present study was to test the hypothesis that HGF and VEGF concentrations may vary according to the different markers of CHF severity and to analyze the impact of HGF and VEGF concentrations on the cardiovascular mortality of patients with CHF. Methods: We studied 529 consecutive patients who were referred to our center for an evaluation of left ventricular dysfunction. Hepatocyte growth factor and vascular endothelial growth factor levels were determined on blood samples obtained on entry into the study. Clinical follow-up(median 988 days) was obtained for 528 patients. Results: Hepatocyte growth factor concentrations were strongly associated with age, diabetes mellitus, and all markers of CHF severity; by contrast, baseline characteristics did not differ among VEGF tertiles. Cardiovascular survival rates at 1, 2, and 3 years were 91%, 87%, and 80%, respectively. The survival curves indicated a worse outcome for patients with high HGF concentrations at baseline(Pntrast, cardiovascular survival was similar across the tertiles of VEGF(P=.37). Hepatocyte growth factor concentrations were higher in the 109 patients with a cardiovascular event(1001[741-1327] pg/mL) than in the 419 patients without(773[610-1045] pg/mL, Pnalysis, a baseline HGF concentration >802 pg/mL was associated with an increased cardiovascular mortality(hazard ratio=1.85, 95%CI 1.09-3.13, P=.02); other variables retained into the final model were B-type natriuretic peptide(Pn consumption(P=.0002), and ischemic etiology(P=.0005). Conclusions: Hepatocyte growth factor levels correlate with CHF severity and are associated with an increased cardiovascular mortality during follow-up.

关键词：心衰患者充血性心衰循环水平血管内皮生长因子(VEGF) 细胞因子血管源性预后意义 CHF患者肝细胞生长因子左心室功能不全

儿童异常头位致病原因的眼科、整形外科及神经病学的多学科研究

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世界核心医学期刊文摘（眼科学分册） 2005年第12期1卷 9-10页

作者： nucci P Kushner B.j Serafino M Orzalesi n 陈立军 Kushner Department of Ophthalmology and Visual Sciences 2870UniversityAvenueMadisonWI 53705United States.Dr

PURPOSE: To determine the relative frequency that abnormal head postures in children are caused by orthopedic, ophthalmologic, or neurologic disorders, respectively. DESIGn: A prospective, consecutive case series. METHODS: Children found to have an abnormal head posture on routine pediatric examination underwent an evaluation by a pediatric ophthalmologist, pediatric orthopedist, and pediatric neurologist. The study was conducted in northwestern Italy. RESULTS: In the 63 children evaluated, the cause of the abnormal head posture was orthopedic in 35, ocular in 25, and neurologic in 5. In 8 patients, no specific cause could be found. The most common orthopedic cause was congenital muscular torticollis, which accounted for 31 patients. The most common ocular cause was superior oblique muscle palsy, which accounted for 12 patients. In 2 patients neck muscle contracture suggested an orthopedic cause, however, the tight neck muscles were secondary to a head tilt caused by superior obliquemuscle palsy. COnCLUSIOnS: When the cause of an abnormal head posture is not obvious, a multi-disciplinary approach including ophthalmologic, neurologic, and orthopedic specialists may be helpful.

关键词：整形外科神经病学多学科研究先天性肌性斜颈神经系统疾病肌肉挛缩上斜肌麻痹神经科医生病例研究肌肉僵直

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偏心气锚

石油石化节能 1998年第7期 13-26页

作者： j.n.McCoy A.L.Podio 李碧华张荣兰大庆油田设计院

一种新型气锚已经设计出来，并对其进行了现场测试。由于这种气锚采用了将叠板弹簧置于气锚套筒和套管内壁之间，而将气锚套筒靠在套管内壁上的偏心结构，气锚进口开在液体浓度较高的套管内壁处，因而效率有所提高。对气体干扰影响泵效... 详细信息

一种新型气锚已经设计出来，并对其进行了现场测试。由于这种气锚采用了将叠板弹簧置于气锚套筒和套管内壁之间，而将气锚套筒靠在套管内壁上的偏心结构，气锚进口开在液体浓度较高的套管内壁处，因而效率有所提高。对气体干扰影响泵效的油井，这种偏心气锚可能会显著提高产量。

关键词：偏心气锚抽油井套管现场试验

功能性消化不良、胃排空延迟与生活质量下降的关系

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世界核心医学期刊文摘（胃肠病学分册） 2006年第11期2卷 31-32页

作者： Talley n.j. Locke III G.R. LahrB.D. 尹勇 Mayo Clinic 200 First Street SW Rochester MN 55905 United States Prof.

Background: It remains controversial as to whether delayed gastric emptying in functional dyspepsia is associated with a specific symptom pattern, and it is unknown if gastric emptying in functional dyspepsia is a driver of impaired health related quality of life (HRQOL). We aimed to evaluate the relationship between functional dyspepsia symptoms, gastric emptying, and HRQOL. Methods: US patients (n = 864; mean age 44 years (range 18-82); 74%female) with functional dyspepsia, as defined by Rome Ⅱ criteria, were enrolled into one of four clinical trials. All patients had a baseline scintigraphic assessment of gastric emptying of an egg substitute meal, and the trials were stratified on this assessment. Delayed gastric emptying was defined as having at least 6.3%residual volume at four hours. A total of 290 (34%) patients had delayed gastric emptying. HRQOL was assessed by the SF 36 and nepean dyspepsia index (nDI). Results: Postprandial fullness was independently associated with delayed gastric emptying but the association was weak (odds ratio (OR) 1.98 (95%confidence interval (CI) 1.02, 3.86); p = 0.04). no independent association was seen with epigastric pain, early satiety, nausea, or bloating. Mean SF 36 physical composite score (PCS) was 42.3 (95%CI 41.6, 43.0) and the mean SF 36 mental composite score (MCS) was 46.8 (95%CI 46.0, 47.5); both mean scores were significantly lower than age and sex adjusted national norms of 50 (p ncreasing age, and higher symptom scores for fullness, epigastric pain, and nausea were each independently associated with decreased PCS scores (all p ne nausea symptom score, lower gastric emptying rates at one hour, and lower body mass index were associated with decreased MCS (all p n, and nausea, but not gastric emptying, were associated with an impaired score on the nDI. However, the magnitude of the significant associations were all small. Conclusions: In

关键词：胃排空延迟生活质量胃排空率罗马Ⅱ标准闪烁扫描促发因素特异性症状胃残留恶心症状临床试

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神经毒性杀虫剂WL108477

农药 1987年第5期 46-48页

作者： M.Harris R.n.Price j.Robinson 陈春生

1978年Soloway叙述了硝基亚甲基杂环(nMH_s)类杀虫剂的开发,并讨论了这类化合物的结构活性关系。此类杀虫剂显示令人感兴趣的生物活性和速效作用,缺点是光不稳定性,妨碍其工业化生产。近来开发的WL108477是2-硝基亚甲基-1,3-噻嗪烷的n-... 详细信息

1978年Soloway叙述了硝基亚甲基杂环(nMH_s)类杀虫剂的开发,并讨论了这类化合物的结构活性关系。此类杀虫剂显示令人感兴趣的生物活性和速效作用,缺点是光不稳定性,妨碍其工业化生产。近来开发的WL108477是2-硝基亚甲基-1,3-噻嗪烷的n-甲酰衍生物,它既保留了所需要的生物活性,又具有较高的光稳定性,还保持母体化合物的速效作用。试验结果表明,该化合物对多种害虫,包括对有机磷、氨基甲酸酯和拟除虫菊酯杀虫剂产生抗性的品系,均有高效,其中有些昆虫是病毒的传播媒介,如水稻上的蜡

关键词：氨基甲酸除虫菊有机磷化合物宿根花卉 WL108477 敏感品系硝基亚甲基

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井下气体分离器提高有杆泵抽油井的产量

石油石化节能 1997年第1期 15-17页

作者： j.n．McCoy A．L．Podio M．D．Woods 谷溢华北油田采油工艺研究所

本文例举了几种井下气体分离器。重点介绍了偏心连续流动气体分离器的偏心的影响、设计、制造、能力、现场应用及室内研究。这种分离器用316不锈钢薄壁管制造，流通面积大，借助301不锈钢弹簧偏心器把进出孔眼定位于高液气比区域。现场... 详细信息

本文例举了几种井下气体分离器。重点介绍了偏心连续流动气体分离器的偏心的影响、设计、制造、能力、现场应用及室内研究。这种分离器用316不锈钢薄壁管制造，流通面积大，借助301不锈钢弹簧偏心器把进出孔眼定位于高液气比区域。现场应用效果好，泵的充满度由44％提高到97％，产量平均增加24％，在开采相同产量情况下平均工作时间显著减少。

关键词：油气分离器油气开采有杆泵设计现场应用实验室试验