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71.
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应用压力早期恢复资料确定低渗地层压力   总被引:3,自引:0,他引:3  
魏芳 《长江大学学报》2007,4(3):42-43,52
低渗透油藏的压力恢复曲线,不能用Horner外推压力求取地层压力。基于Horner方程的等轴双曲线形式,提出了应用压力早期恢复资料确定低渗地层压力的新方法。通过油井实际资料计算验证,用该方法计算的地层压力准确可靠,较好地解决了低渗透油藏求地层压力的问题。  相似文献   
73.
BACKGROUND: Interpretation of serial urine protein:creatinine (UPC) values is confounded by a lack of data regarding random biologic variation of UPC values in dogs with stable glomerular proteinuria. HYPOTHESIS: That there is minimal day-to-day variability in the UPC of dogs with unchanging proteinuria and the number of measurements needed to reliably estimate UPC varies with the magnitude of proteinuria. ANIMALS: Forty-eight heterozygous (carrier) female dogs with X-linked hereditary nephropathy (XLHN) causing stable proteinuria. METHODS: Urine samples were obtained daily by cystocentesis for 3 consecutive days on 183 occasions (549 samples). The UPC was measured for each sample with a single dry-film chemistry auto-analyzer. Data were analyzed retrospectively by a power of the mean model because the variance of UPC values within the 3-day evaluation periods increased as the magnitude of proteinuria increased. RESULTS: To demonstrate a significant difference (P < .05) between serial values in these proteinuric dogs, the UPC must change by at least 35% at high UPC values (near 12) and 80% at low UPC values (near 0.5). One measurement is adequate to reliably estimate the UPC when UPC <4, but 2-5 determinations are necessary at higher UPC values. CONCLUSIONS AND CLINICAL IMPORTANCE: These guidelines for interpretation of serial UPC values in female dogs with XLHN may also be helpful for interpretation of UPC values in dogs with other glomerulopathies.  相似文献   
74.
OBJECTIVE: To examine the feasibility and accuracy of a handheld rebound tonometer, TonoVet, and to compare the intraocular pressure (IOP) readings of the TonoVet with those of an applanation tonometer, TonoPen XL, in normal Eurasian Eagle owls. ANIMALS STUDIED: Ten clinically normal Eurasian Eagle owls (20 eyes). PROCEDURES: Complete ocular examinations, using slit-lamp biomicroscopy and indirect ophthalmoscopy, were conducted on each raptor. The IOP was measured bilaterally using a rebound tonometer followed by a topical anesthetic agent after 1 min. The TonoPen XL tonometer was applied in both eyes 30 s following topical anesthesia. RESULTS: The mean +/- SD IOP obtained by rebound tonometer was 10.45 +/- 1.64 mmHg (range 7-14 mmHg), and by applanation tonometer was 9.35 +/- 1.81 mmHg (range 6-12 mmHg). There was a significant difference (P = 0.001) in the IOP obtained from both tonometers. The linear regression equation describing the relationship between both devices was y = 0.669x + 4.194 (x = TonoPen XL and y = TonoVet). The determination coefficient (r(2)) was r(2) = 0.550. CONCLUSIONS: The results suggest that readings from the rebound tonometer significantly overestimated those from the applanation tonometer and that the rebound tonometer was tolerated well because of the rapid and minimal stress-inducing method of tonometry in the Eurasian Eagle owls, even without topical anesthesia. Further studies comparing TonoVet with manometric measurements may be necessary to employ rebound tonometer for routine clinical use in Eurasian Eagle owls.  相似文献   
75.
为了筛选出对温室白粉虱高效的农药复配组合,本试验选择9种杀虫单剂对田间采集的温室白粉虱进行了毒力测定,并利用共毒因子和共毒系数对氟吡呋喃酮与8种杀虫剂复配组合的联合毒力进行评价,同时对筛选出的药剂进行田间药效试验。结果表明:杀虫单剂毒力测定中,LC50最低的为鱼藤酮,最高的为螺虫乙酯,48 h LC50分别为0.43μg/mL和78.59μg/mL;毒力大小顺序为鱼藤酮>氟啶虫胺腈>除虫菊素>苦参·印楝素>d-柠檬烯>氟吡呋喃酮>啶虫脒>高效氯氰菊酯>螺虫乙酯。共毒系数大于120的复配组合为氟吡呋喃酮与d-柠檬烯5∶1、氟吡呋喃酮与苦参·印楝素1∶2和1∶5,共毒系数分别为268.31、247.80和241.46,LC50分别为5.76、4.51μg/mL和4.34μg/mL。氟吡呋喃酮与d-柠檬烯5∶1复配增效作用明显,为最佳配比。田间药效试验表明,10 d后,17%氟吡呋喃酮可溶液剂与1%苦参·印楝素乳油、5%d-柠檬烯可溶液剂复配对温室白粉虱的防效达到83.5%~83...  相似文献   
76.
为探究低磷胁迫对红豆草(Onobrychis viciaefolia)光合作用、叶绿素荧光以及内源激素的影响,本试验采用营养液沙培法,以耐低磷5号和磷敏感1号红豆草为试验材料,设置常磷(1.00 mmol·L-1 KH2PO4)和低磷(0.01 mmol·L-1 KH2PO4)胁迫处理,于不同胁迫天数后测定形态、光合以及内源激素含量变化。结果表明:低磷胁迫抑制红豆草生长和光合作用,在低磷胁迫下,除非光化学淬灭系数外,供试红豆草叶绿素荧光参数均下降。随着胁迫时间的延长,2份红豆草材料地上和地下部玉米素(ZT)、脱落酸(ABA)、生长素(IAA)和赤霉素(GA3)及其之间的比值变化趋势不一致,耐低磷红豆草地上和地下部ZT,GA3,IAA,ABA耐低磷系数大于磷敏感材料。相关性分析表明,IAA与光合作用和叶绿素荧光显著相关,ABA与IAA,ZT,GA3呈负相关。研究结果可为红豆草耐低磷特性研究提供...  相似文献   
77.
ObjectiveTo compare the effect of propofol, alfaxalone and ketamine on intraocular pressure (IOP) in cats.Study designProspective, masked, randomized clinical trial.AnimalsA total of 43 ophthalmologically normal cats scheduled to undergo general anesthesia for various procedures.MethodsFollowing baseline IOP measurements using applanation tonometry, anesthesia was induced with propofol (n = 15), alfaxalone (n = 14) or ketamine (n = 14) administered intravenously to effect. Then, midazolam (0.3 mg kg?1) was administered intravenously and endotracheal intubation was performed without application of topical anesthesia. The IOP was measured following each intervention. Data was analyzed using one-way anova and repeated-measures mixed design with post hoc analysis. A p-value <0.05 was considered significant.ResultsMean ± standard error IOP at baseline was not different among groups (propofol, 18 ± 0.6; alfaxalone, 18 ± 0.7; ketamine, 17 ± 0.5 mmHg). Following induction of anesthesia, IOP increased significantly compared with baseline in the propofol (20 ± 0.7 mmHg), but not in the alfaxalone (19 ± 0.8 mmHg) or ketamine (16 ± 0.7 mmHg) groups. Midazolam administration resulted in significant decrease from the previous measurement in the alfaxalone group (16 ± 0.7 mmHg), but not in the propofol group (19 ± 0.7 mmHg) or the ketamine (16 ± 0.8 mmHg) group. A further decrease was measured after intubation in the alfaxalone group (15 ± 0.9 mmHg).Conclusions and clinical relevancePropofol should be used with caution in cats predisposed to perforation or glaucoma, as any increase in IOP should be avoided.  相似文献   
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79.
ObjectiveTo evaluate agreement between end-tidal carbon dioxide (Pe′CO2) and PaCO2 with sidestream and mainstream capnometers in mechanically ventilated anesthetized rabbits, with two ventilatory strategies.Study designProspective experimental study.AnimalsA total of 10 New Zealand White rabbits weighing 3.6 ± 0.3 kg (mean ± standard deviation).MethodsRabbits anesthetized with sevoflurane were intubated with an uncuffed endotracheal tube (3.0 mm internal diameter) and adequate seal. For Pe′CO2, the sidestream capnometer sampling adapter or the mainstream capnometer was placed between the endotracheal tube and Bain breathing system (1.5 L minute–1 oxygen). PaCO2 was obtained from arterial blood collected every 5 minutes. A time-cycled ventilator delivered an inspiratory time of 1 second and 12 or 20 breaths minute–1. Peak inspiratory pressure was initially set to achieve Pe′CO2 normocapnia of 35–45 mmHg (4.6–6.0 kPa). A total of five paired Pe′CO2 and PaCO2 measurements were obtained with each ventilation mode for each capnometer. Anesthetic episodes were separated by 7 days. Agreement was assessed using Bland-Altman analysis and linear mixed models; p < 0.05.ResultsThere were 90 and 83 pairs for the mainstream and sidestream capnometers, respectively. The mainstream capnometer underestimated PaCO2 by 12.6 ± 2.9 mmHg (proportional bias 0.44 ± 0.06 mmHg per 1 mmHg PaCO2 increase). With the sidestream capnometer, ventilation mode had a significant effect on Pe′CO2. At 12 breaths minute–1, Pe′CO2 underestimated PaCO2 by 23.9 ± 8.2 mmHg (proportional bias: 0.81 ± 0.18 mmHg per 1 mmHg PaCO2 increase). At 20 breaths minute–1, Pe′CO2 underestimated PaCO2 by 38.8 ± 5.0 mmHg (proportional bias 1.13 ± 0.10 mmHg per 1 mmHg PaCO2 increase).Conclusions and clinical relevanceBoth capnometers underestimated PaCO2. The sidestream capnometer underestimated PaCO2 more than the mainstream capnometer, and was affected by ventilation mode.  相似文献   
80.
土质边坡稳定安全系数的计算值主要与采用的简化计算方法和土工参数有关。采用正交试验法计算分析了不同的计算方法、材料参数、水位及其相关荷载、地震作用等对边坡安全系数计算值的影响,进而对设计中的计算方法和材料参数提出了一些有益的建议,并提出了在工程运行管理中应尽量避免低水位或水位骤降情况的意见,为土石坝类工程的设计与运行管理提供了重要参考。  相似文献   
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