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81.
AIM: To examine the alteration of pathologic structure and gaseous molecules in rats with pulmonary hypertension induced by high pulmonary blood flow.METHODS: Aortocaval shunting was produced for 11 weeks in rats, and pulmonary hemodynamics was evaluated.Pulmonary vascular micro- and ultra- structure was also examined.Meanwhile,the concentration of plasma nitric oxide (NO) and carbon monoxide (CO) was measured by spectrophotometry.The expression of endothelial nitric oxide synthase (eNOS) and heme oxygenase-1 (HO-1) in pulmonary arteries was detected by immunohistochemistry.RESULTS: After 11- week aortocaval shunting,pulmonary artery mean pressure was significantly increased.Muscularization of small pulmonary vessels and relative medial thickness and area of pulmonary arteries were obviously increased in shunting rats compared with controls.Ultrastructure of intrapulmonary arteries changed obviously in shunting rats.Meanwhile,plasma NO concentration was increased and eNOS expression in pulmonary artery endothelial cells was significantly augmented in rats of shunting group.Plasma carbon monoxide level and HO-1 expression in puomonary artery smooth muscle cells,however,were not altered in shunting rats.CONCLUSIONS: Pulmonary vascular structural remodeling is the important pathologic basis of pulmonary hypertension induced by a left-to-right shunt,and NO other than CO might play an important regulating role in the development of high pulmonary blood flow-induced pulmonary hypertension.  相似文献   
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An 18-month-old male Dalmatian dog was presented for veterinary evaluation after the pet owner observed a sudden onset of weakness. An acquired continuous cardiac murmur was detected on physical examination. Two-dimensional echocardiographic examination revealed structural abnormalities of the proximal aorta and pulmonic valve. Doppler echocardiographic studies and cardiac catheterization demonstrated the presence of a proximal aorticopulmonary shunt. A diagnosis of left aortic sinus rupture and aorticopulmonary fistula was made. Antemortem diagnosis of aortic sinus rupture in the dog has not, to our knowledge, been reported previously. The anatomical variant of left aortic sinus rupture resulting in the development of a fistula from the aorta to the main pulmonary artery is, apparently, uncommon in all species.  相似文献   
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Silicone tubing was used to divert aqueous humor from the anterior chamber of the right eye to the rostral compartment of the right frontal sinus in four clinically normal mixed-breed dogs. Biomicroscopic examination, and pneumoapplanation tonometry and tonography, completed for up to 18 weeks postoperatively, confirmed gonioimplant function in all four cases. The dogs were euthanized at 6, 8, 16 and 18 weeks postoperatively. Gonioimplant patency was further confirmed by postmortem examination of the globes, implants and frontal sinuses. Gross and light microscopic examinations revealed iridal attachments to the implant ( n  = 4), mild anterior uveitis ( n  = 3), anterior subcapsular cataracts ( n  = 4), and focal corneal ( n  = 3) and scleral ( n  = 3) scarring in the operated globes. Light microscopic examination of frontal sinus specimens revealed mild lymphocytic proliferation and fibrosis immediately adjacent to the implant entrance site. There were no bacteria detected on aerobic or anaerobic cultures of the frontal sinuses or light microscopic examination of the globes or frontal sinuses. Results indicate that the frontal sinus shunting of aqueous humor is a safe and effective means of extraorbital aqueous diversion with potential applicability in the management of glaucoma.  相似文献   
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针对强风时自动集沙仪测量精度和集沙效率受扰动问题,提出了分流对冲与多级扩容组合降速法,设计了分流对冲与多级扩容组合式自动集沙仪,阐述了风沙分离器和数据无线采集系统的设计原理,并对风沙分离器降速及分离性能、集沙仪抗强风干扰性能和集沙效率等进行了试验分析。结果表明,分流对冲与多级扩容组合式自动集沙仪具备了抗强风干扰性能,可实时、连续和远距离无线采集数据,自由旋转的起动风速为4.23 m/s,等动力性为92.94%,平均集沙效率为90.42%,当风速低于18 m/s时,粒径55.36μm以上的土样只要进入集沙仪,就可被完全收集;数据无线采集系统的供电续航能力达31 h以上,无障碍时信号传输距离为208.51 m,可较好地满足土壤风蚀量的自动观测需求。  相似文献   
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目的 探讨腹腔内高压致侧脑室-腹腔分流术后腹腔端分流管阻塞的治疗经验.方法 收集本院自2006年2月至2010年10月腹腔内高压致侧脑室-腹腔分流术后腹腔端分流管阻塞的患者12例,采用乳胶管暂时性外引流解除阻塞,回顾性分析其临床资料.结果 术后引流管通畅,每日脑脊液外引流量100-350 mL,平均(212.6±30....  相似文献   
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γ-氨基丁酸旁路(GABA shunt)普遍存在于原核和真核生物体中,对于动物、植物和微生物具有不同的生理功能.苏云金芽胞杆菌gab基因簇中gabT和gabD基因所编码的γ-氨基丁酸转氨酶和琥珀酸半醛脱氢酶参与GABA shunt.在前期研究获得的苏云金芽胞杆菌HD-73菌株gabT、gabR(gab基因簇中的调控基因)和gabD基因缺失突变菌株的基础上,从菌株生长、芽胞产量和晶体蛋白产量等方面研究GABA shunt阻断对Bt芽胞和晶体形成的影响.结果表明,GABA shunt阻断对芽胞产量有一定影响,但对Bt生长和晶体蛋白产量无明显影响  相似文献   
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