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51.
52.
Kim YH; de Kretser DM; Temple-Smith PD; Hearn MT; McFarlane JR 《Molecular human reproduction》1997,3(4):307-313
Using mechanical and chemical dissection methods, fibrous sheath was
isolated both from normal ejaculated human spermatozoa and from rabbit
cauda epididymal spermatozoa. The same techniques did not produce a pure
preparation of fibrous sheath from ejaculated rabbit spermatozoa,
suggesting that further cross-linking and stabilization of sperm structures
occurs in response to components of the seminal plasma. The isolation
procedures were monitored by phase contrast microscopy and the purity of
the fibrous sheath was verified by electron microscopy. Sodium dodecyl
sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of isolated human
fibrous sheath revealed at least 14 protein bands of which the most
intensely stained were of molecular weight 84, 72, 66.2, 57, 32 and 28.5
kDa. The rabbit fibrous sheath revealed at least 10 protein bands, of which
the most intensely stained were 35.2, 32.7 and 28.5 kDa. The amino acid
composition of the purified fibrous sheath from human and rabbit
spermatozoa was similar, being high in aspartic acid and/or asparagine and
glutamic acid and/or glutamine, serine, alanine, leucine, lysine and
glycine, but low in histidine, tyrosine and isoleucine. This composition is
similar to that reported for the rat and suggests that mammalian sperm tail
fibrous sheaths are composed of similar types of proteins, although there
are apparent differences in protein components between species.
相似文献
53.
G Jancso MT Jaberansari B Gasz Z Szanto B Cserepes E Rth 《Experimental & Clinical Cardiology》2004,9(1):21-25
OBJECTIVES:
To show that angiotensin-converting enzyme (ACE) inhibition potentiates subthreshold ischemic preconditioning (IPC) via the elevation of bradykinin activity, leading to a fully delayed cardioprotective response.METHODS:
On day 1 of the experiment, pigs were subjected to sham (group 1, controls) or IPC protocols. In groups 2 and 3, 4×5 min and 2×2 min of IPC, respectively, were elicited by occluding the left anterior descending coronary artery with percutaneous transluminal coronary angioplasty inflatable balloon catheter. Group 4 was subjected to the ACE inhibitor perindoprilate only. In group 5, the pigs were pretreated with perindoprilate (0.06 mg/kg) and then subjected to 2×2 min IPC. In group 6, intracoronary HOE 140 (a selective bradykinin B2 receptor antagonist) was added before the perindoprilateaugmented subthreshold (2×2 min) PC stimulus. On the second day, all animals underwent 40 min left anterior descending coronary artery ligation and 3 h reperfusion, followed by infarct size analysis using triphenyl tetrazolium chloride staining.RESULTS:
The rates of infarct size and risk zone were the following in the experimental groups: group 1, 42.8%; group 2,19.5% (P<0.05); group 3, ischemia/reperfusion (I/R) 33.4%; group 4, I/R 18.4% (P<0.05); group 5, I/R 31.2%; and group 6, I/R 36.3%. A significant increase of nuclear factor kappa B activation in groups 2 and 4 was seen.CONCLUSIONS:
Results confirm that ACE inhibitors do not give total pharmacological IPC, but they enhance the induction effect of small ischemic insults, which raises the ischemic tolerance of myocardium. It was determined that enhanced bradykinin activity leads to downstream nuclear factor kappa B activation in this model. 相似文献54.
McNamara MT; Brant-Zawadzki M; Berry I; Pereira B; Weinstein P; Derugin N; Moore S; Kucharczyk W; Brasch RC 《Radiology》1986,158(3):701-705
The effects of a paramagnetic contrast agent, gadolinium-DTPA (Gd-DTPA), on magnetic resonance (MR) imaging of acute cerebral ischemia was investigated in a feline model of middle cerebral artery occlusion. Imaging was performed both before and after administration of an intravenous dose of 0.2 mmol/kg of Gd-DTPA. The animals were then sacrificed for pathologic correlation. No changes in intensity or relaxation times were noted before or after Gd-DTPA administration in two animals with 2 hours of occlusion. Infarcts were noted before and after contrast enhancement in all six cats with ischemia of greater than 16-hours duration. Gd-DTPA caused significant increase in intensity of infarct but not in that of normal cerebral tissue. Rapid enhancement was visible in infarcts of 16-24 hours, but such enhancement was slower in infarcts of 72-168 hours, presumably owing to slowed inflow caused by increased vasogenic edema in the latter group. Contrast enhancement of acute cerebral ischemic lesions with Gd-DTPA offers no improvement in sensitivity of MR imaging, although the conspicuity of the lesion may be improved. Additionally, contrast media may provide potential temporal and pathophysiological data for better characterization of cerebral ischemia. 相似文献
55.
Many new products designed to assist in rapid blood infusion are appearing. Some highly touted and routinely used devices for intravenous (IV) infusion have recently been shown to be, at least in part, defective. A tubing with an in-line 150 μ filter (150 μ High-Flow Blood Filter; Saftifllter® Blood Administration Sets; Cutter Biological, Berkeley, CA 94710) has recently been introduced to facilitate rapid blood transfusion. It is claimed that at least 8.5 units of blood can be rapidly run through each set before replacement is necessary. To test this under simulated clinical conditions, four sets of ten random units of outdated erythrocytes at 4 to 9°C were each admixed with 250 mL 70°C 0.9 NaCl and infused through the system under a constant 300 mmHg pressure. Two sets infused through unmodified tubing flowed at an average of 25 mL/sec (1500 mL/min) before there was an appreciable slowing of the flow rate. Two sets with 8 Fr catheters attached infused at an average of 22 mL/sec (1320 mL/min) before there was an appreciable slowing of the flow rate. Even after the flow slowed, the 9th and 10th units infused at an average greater than 10 mL/sec (600 ml/min). The tubing/filter exceeded the manufacturer's published claims. This tubing/filter appears to be one element that could be an effective component of a high-flow infusion system. 相似文献
56.
Transient synovitis of the hip in children: role of US 总被引:7,自引:0,他引:7
Marchal GJ; Van Holsbeeck MT; Raes M; Favril AA; Verbeken EE; Casteels- Vandaele M; Baert AL; Lauweryns JM 《Radiology》1987,162(3):825-828
Transient synovitis of the hip remains a common diagnostic problem for the clinician. The physical signs are not pathognomonic of the condition, and the classic technical examinations are of little help. Therefore, the authors retrospectively studied the value of hip arthrosonography in 46 children with clinical symptoms suggesting pathologic hip conditions. In 20 of the 21 patients with a final diagnosis of transient synovitis, articular effusion was detected on ultrasound (US). Conventional radiography showed an increased medial joint space in only eight of these patients. Increased echogenicity of the articular fluid was found in both transient synovitis and septic arthritis. The high sensitivity of US in detecting intraarticular fluid was demonstrated by cadaver studies. 相似文献
57.
S Majewski FX Bosch J. Dillner O-E Iversen SK Kjaer N Muñoz S-E Olsson J Paavonen K Sigurdsson J Bryan MT Esser K Giacoletti M James F Taddeo S Vuocolo E Barr 《Journal of the European Academy of Dermatology and Venereology》2009,23(10):1147-1155
Background Quadrivalent human papillomavirus (HPV types 6/11/16/18) L1 VLP vaccine is highly effective in preventing HPV 6/11/16/18-related cervical and external genital disease. Herein, we evaluated the impact of the quadrivalent HPV 6/11/16/18 L1 VLP vaccine on prevention of HPV-associated cervico-genital lesions in a broad population of sexually active European women.
Methods Female subjects ( N = 9265) aged 16–24 with four or fewer lifetime sexual partners were enrolled and randomized to quadrivalent HPV vaccine or placebo. Subjects underwent cervicovaginal sampling for HPV DNA detection. Papanicolaou testing and anti-HPV 6/11/16/18 serology testing was also performed.
Results Vaccine efficacy against lesions representing immediate cervical cancer precursors (cervical intraepithelial neoplasia grade 2/3 or adenocarcinoma in situ ) related to HPV 6/11/16/18 in the per-protocol population was 100.0%[95% confidence interval (95% CI), 89.8–100.0]. Efficacy against external genital lesions (vulvar or vaginal intraepithelial neoplasia, condyloma, vulvar or vaginal cancer) related to vaccine HPV types in the per-protocol European population was 99.0% (95% CI, 94.4–100.0).
Conclusion These data demonstrate that quadrivalent HPV 6/11/16/18 vaccination programs in 16- to 24-year-old European women can be beneficial.
NCT0009252, NCT00092534, NCT00092495 相似文献
Methods Female subjects ( N = 9265) aged 16–24 with four or fewer lifetime sexual partners were enrolled and randomized to quadrivalent HPV vaccine or placebo. Subjects underwent cervicovaginal sampling for HPV DNA detection. Papanicolaou testing and anti-HPV 6/11/16/18 serology testing was also performed.
Results Vaccine efficacy against lesions representing immediate cervical cancer precursors (cervical intraepithelial neoplasia grade 2/3 or adenocarcinoma in situ ) related to HPV 6/11/16/18 in the per-protocol population was 100.0%[95% confidence interval (95% CI), 89.8–100.0]. Efficacy against external genital lesions (vulvar or vaginal intraepithelial neoplasia, condyloma, vulvar or vaginal cancer) related to vaccine HPV types in the per-protocol European population was 99.0% (95% CI, 94.4–100.0).
Conclusion These data demonstrate that quadrivalent HPV 6/11/16/18 vaccination programs in 16- to 24-year-old European women can be beneficial.
NCT0009252, NCT00092534, NCT00092495 相似文献
58.
Raczak G la Rovere MT Pinna GD Maestri R Swiatecka G 《Clinical science (London, England : 1979)》2001,100(1):33-41
The purpose of the present study was to assess the agreement between measurements of baroreflex sensitivity (BRS) obtained by the Valsalva manoeuvre and by the phenylephrine test in patients with previous myocardial infarction and different degrees of left ventricular dysfunction. Patients with a previous myocardial infarction were enrolled consecutively into two groups according to their left ventricular ejection fraction (LVEF): 40% (n=52). All patients underwent BRS assessment by the phenylephrine technique (Phe-BRS) and by the Valsalva manoeuvre, with the latter using both the overshoot part of phase IV (Ov-VM-BRS) and the whole of phase IV (IV-VM-BRS). The linear association between methods was assessed by correlation analysis and the agreement was evaluated by computing the bias and the limits of agreement. IV-VM-BRS and Ov-VM-BRS could not be computed in 26% and 39% of patients respectively. For both indices a much higher percentage of non-computable Valsalva manoeuvre slopes was found in the group of patients with LVEF 40% the results were: r=0.91 (P<0.001), bias=0.1 ms/mmHg (P=0.84) and limits of agreement from -4.8 to 5 ms/mmHg. When comparing Phe-BRS and IV-VM-BRS, we found r=0.67 (P=0.001), bias=-1.5 ms/mmHg (P=0.06) and limits of agreement from -8.8 to 5.7 ms/mmHg in the group of patients with LVEF 40%. Dichotomizing Ov-VM-BRS, the best cut-off value to identify patients with a Phe-BRS of <3 ms/mmHg was found to be 7 ms/mmHg, giving 100% sensitivity and 69% specificity. In conclusion, estimation of BRS by the Valsalva manoeuvre in post-myocardial infarction patients is limited by a large number of non-measurable results. When computable, measurements are well correlated with those obtained by Phe-BRS, but, because of large limits of agreement, the two methods cannot be used interchangeably. If used as a screening test for risk stratification, the Valsalva manoeuvre could reduce by about one-third the need for phenylephrine injection. 相似文献
59.
F Mercuriali ; G Gualtieri ; L Sinigaglia ; G Inghilleri ; E Biffi ; A Vinci ; MT Colotti ; G Barosi ; G Lambertengh Deliliers 《Transfusion》1994,34(6):501-506
BACKGROUND: In rheumatoid arthritis (RA) patients undergoing orthopedic surgery, anemia is the major factor in the use of allogeneic blood. STUDY DESIGN AND METHODS: To determine whether recombinant human erythropoietin (rHuEPO) could allow preoperative autologous blood procurement and reduce allogeneic blood exposure, 11 RA patients who were unable preoperatively to deposit blood for autologous use because of their anemia (baseline hematocrit < 34% [0.34]) and who were scheduled for primary total hip replacement or total knee replacement were treated intravenously with 300 U per kg of rHuEPO in combination with intravenous iron saccharate (100 mg), given twice weekly for 3 weeks. The transfusion treatment was compared with that in 12 control patients with comparable baseline hematologic values who underwent the same operation. RESULTS: Control patients could not preoperatively deposit any blood for autologous use, while all but one of the rHuEPO- treated patients deposited 2 or more units (mean, 2.6 +/− 0.6; range, 2- 4) (p < 0.001). The control group received more allogeneic units (2.6 +/− 1.6 vs. 0.8 +/− 0.8) (p = 0.009). Moreover, 50 percent of the rHuEPO-treated patients, as compared with 8 percent of controls, completely avoided allogeneic transfusion. CONCLUSION: Recombinant human erythropoietin is safe and effective in stimulating erythropoiesis, allowing preoperative donation of blood for autologous use, and reducing exposure to allogeneic blood for RA patients who are unable preoperatively to deposit blood because of anemia. 相似文献
60.
目的:观察针刺足三里、悬钟2穴对缺血性脑卒中脑血管功能的影响,分析其可能的作用机制,并对临床疗效做出评价。方法:选择2004-11/2006-05湖北中医药高等专科学校附属古城医院针灸科、荆州市第五人民医院中医康复科、荆州市第三人民医院中医科3单位缺血性脑卒中患者合适病例160例,采用查随机数字表的方法,将其随机分为对照组和针刺组,各80例。对照组采用现代医学常规干预方法进行治疗:卧床,保持呼吸道通畅,预防感染,控制颅内压、血压,维持水电解质平衡。针刺组在此基础上加针刺足三里、悬钟2穴,采用慢速捻转进针法针刺,留针20~30min,每隔5min行针1次。1次/d。两组患者治疗30d。并以经颅多普勒检测观察缺血性脑卒中患者治疗前后脑血管舒缩反应能力、脑血流自动调节功能、大脑半球侧枝循环代偿功能的变化,同时以治疗前后神经功能缺损程度为指标评价其临床疗效。结果:160例病例全部进入结果分析。①针刺组与治疗前相比,脑血管舒缩反应能力明显加强,差异有显著性意义(t=2.97,P<0.05),且优于对照组(t=2.45,P<0.05)。②针刺组与治疗前相比,脑血流自动调节能力明显改善,差异有非常显著性意义(t=8.01,P<0.01),且优于对照组(t=7.67,P<0.05)。③针刺组与治疗前相比,大脑半球侧枝循环代偿功能得到加强,差异有显著性意义(t=3.15,P<0.05),且优于对照组(t=5.16,P<0.05)。④针刺组与治疗前相比,神经功能缺损积分明显降低,差异有非常显著性意义(t=4.83,P<0.01),且优于对照组(t=5.43,P<0.05)。结论:针刺足三里、悬钟2穴对缺血性脑卒中患者脑血管舒缩反应能力、脑血流自动调节功能、大脑半球侧枝循环代偿功能有明显改善作用,并能促进神经功能的恢复。 相似文献