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41.
The component of a composite prosthesis, which makes contact with the visceral peritoneum, can be reabsorbable or non-reabsorbable, and laminar or reticular. This study was designed to determine whether the composition of this second, barrier component could improve its behavior at this interface. Abdominal wall defects in rabbits were repaired using a polypropylene prosthesis (PP), or the composites Sepramesh (PP+h) or Vicryl (PP+v). Fourteen days after surgery, the implants were evaluated by light and scanning electron microscopy, and immunohistochemistry. Prosthetic areas occupied by adhesions (PP: 71.08±5.09, PP+h: 18.55±4.96, P+v: 69.69±16.81%), neoperitoneal thickness (PP: 256.17±21.68, PP+h: 83.11±19.63, PP+v:213.72±35.90 μm) and macrophage counts (PP: 8.73±1.16, PP+h: 27.33±4.13, PP+v: 31.24±3.08%) showed significant differences (P<0.05). The tested biomaterials induced an optimal recipient tissue infiltration. Least adhesion formation was observed on the PP+h implants. This suggests that the second component, although reabsorbable, should be smooth in structure.  相似文献   
42.
Part III of this series of articles, like Part II, reviews the pioneering efforts in the 19th century to improve the quality of artificial teeth. The focus of this article, unlike that of Part II, is specifically modifications in the design of the occlusal anatomy of the 19th century denture teeth, along with the theories of mandibular movement that inspired those modifications. This article concludes the introductory phase of this project, which seeks to unravel the confusing history of the development of (posterior) denture teeth.  相似文献   
43.
目的 拟比较以两种不同方法测定低水平压力支持通气(pressure support ventilation,PSV)病人的气道阻断压(P0.1)与自主呼吸时常规方法测定值的相关性。方法 12例机械通气病人,断开呼吸机自主呼吸时以常规方法测定P0.1得到P0.1-SB:在PSV水平为5cmH20,以常规方法和按压呼气末暂停键测定P0.1分别得到P0.1-PSV5和P0.1-PSV5eeo.分析后二者与前者之间的相关性。结果 P0.1-SB与P0.1-PSV5之间差异无显著性,P0.1-PSV5ee0分别小于P0.1-SB与P0.1-PSV5,差异有显著性;P0.1-PSV5eeo与P0.1-PSV5和P0.1-SB之间的相关系数均为0.97。结论 按压呼气末暂停键测定PSV水平为5cmH2O的P0.1值与常规方法测定的PSV水平为5cmH2O以及自主呼吸时的测定值相比,其值偏小,但前者与后二者之间具有良好的相关性。  相似文献   
44.
Acute ischaemia of the vertebrobasilar circulation leads to a variety of clinical manifestation and is mostly due to cardiogenic or artery-to-artery embolism. We describe four neurological emergency situations involving vertebrobasilar artery aclusion of other origins: basilar migraine, extrinsic compression by rheumatoid inflammatory tissue, generalized vasculitis in subacute rheumatic fever and basilar artery dissection. The differential diagnosis of acute vertebrobasilar artery occlusion may have an important impact on patient management.  相似文献   
45.
为了提高闭胸心肺复苏时心肌冠状循环灌注压(CPP),我们分别观察了用主动脉内带水囊导管周期性阻塞胸主动脉或腹主动脉(OTA/OAA),以及不同剂量肾上腺素(0.02~0.14mg/kg)对CPP的影响。结果:OTA不能提高CPP。然而,在复苏30min内,每3minOAA之后,CPP都比各期阻塞前血压高0.67~1.2kPa(P<0.05或0.01);解除阻塞3 min后,CPP比各期解除前血压低0.8~1.6kPa(P<0.05或0.01)。另外,使用肾卜腺素只在复苏的前9min有效。结论:OAA可以显著提高闭胸心肺复苏时的CPP;在复苏后期,其作用优于大剂量肾上腺素。  相似文献   
46.
老年人视网膜中央血管在前部视神经的解剖特征   总被引:1,自引:0,他引:1  
目的:观察老年人前部视神经视网膜中央血管的解剖特征。 方法:通过组织连续切片和计算机影像分析,观察60~82岁老年人的18只眼球标本中无解剖变异的视网膜中央动脉(CRA)15条,视网膜中央静脉(CRV)23条在筛板前、筛板区及筛板后的管径变化。 结果:老年人筛板前、筛板区、筛板后CRA平均面积的均值分别为(12.70,17.40,18.00)×10-3mm2;平均周长的均值分别为0.56,0.56,0.57mm,平均周长之间相比无显著差异。CRV平均面积的均值分别为(7.00,5.40,7.90)×10-3mm2;平均周长的均值分别为0.44,0.38,0.41mm;CRV平均周长筛板前与筛板区相比,筛板区与筛板后相比均有显著差异。 结论:老年人CRA眼球内外管径一致;CRV在筛板区管径最小。 (中华眼底病杂志,1997,13:213-214)
  相似文献   
47.
应用同种动脉治疗主动脉根部病变   总被引:4,自引:0,他引:4  
报告5例采用同种动脉(HAV)治疗5例主动脉根部病变(主动脉瓣狭窄1例,关闭不全4例)。男3例,女2例;年龄13~47岁。病因为细菌性心内膜炎2例(包括先天主动脉瓣二瓣化畸型1例),Marfan综合征2例,风湿性主动脉瓣关闭不全1例。术中采用同种主动脉全根置换3例(Bentall手术),其中1例用HAV上的二尖瓣前叶加宽主动脉瓣环(Manouguian手术),余2例用自体肺动脉移置主动脉根部,另取同种肺动脉做原位移置(Ross手术)。结果死亡1冽,4例存活,且无并发症发生。术后超声心动图提示主动脉根部良好,无主动脉瓣反流。随访2.5~3.5年疗效满意。  相似文献   
48.
复合带瓣人工血管替换升主动脉和主动脉瓣(24例报告)   总被引:1,自引:0,他引:1  
报告24例升主动脉瘤伴主动脉瓣关闭不全行升主动脉和主动脉瓣替换及冠状动脉开口移植术(Bental术22例,底盘法2例)。13例伴有升主动脉夹层分离,对其中8例DeBakeyI型者,以Teflon毡条内外加固主动脉切端后吻合。13例用人工血管周围间隙与右心耳吻合以控制升主动脉吻合之外的出血。3例以人工血管片环包主动脉吻合口控制局部广泛渗血及出血。2例术毕不能脱离体外循环死亡,手术死亡率83%。随访平均218个月,2例死于蛛网膜下腔出血,1例右股动脉栓塞经手术治愈;其余病人康复良好,心功能(NYHA)I~II级。  相似文献   
49.
PURPOSE: A retrospective, 12-year review of neonatal necrotizing enterocolitis was undertaken at a county hospital, with emphasis on presentation signs and symptoms. METHODS: Eighty-two patients with presence of intramural air were included in the study. The following signs and symptoms were studied: evidence of respiratory distress, use of umbilical catheters, white blood cell count and temperature at presentation, time interval from birth to diagnosis and time interval from diagnosis to operative intervention, presence of intramural air, air in biliary tree or free air, changes in abdominal girth, and presence of occult or gross blood in stools. Comparison was done among infants who had surgical or medical treatment, premature and full-term infants, and infants who had neonatal necrotizing enterocolitis less than or more than 20 days after birth. RESULTS: Eleven patients had a fatal outcome, with an overall survival of 87 percent. Sixty-four patients were treated medically and 18 had operative treatment. Mortality of the surgically treated group was 44 percent. Neonates who had surgical intervention had a left shift of the white blood cell count more commonly present, and all had documented abdominal distention. There were 62 premature and 20 full-term neonates in the group. Full-term neonates developed neonatal necrotizing enterocolitis earlier after birth (5.3 days compared with 15.3 days in the premature neonate group). Full-term neonates had a better prognosis in our series. Presentation of symptoms more than 20 days after birth did not change outcome. CONCLUSION: Our results reflect the experience of a community-based hospital. Clinical acumen remains the cornerstone of diagnosis and management.  相似文献   
50.
1. Endothelium-dependent relaxation in response to acetylcholine (ACh) and the calcium ionophore A 23187 was examined in aorta, coronary, basilar and renal arteries isolated from Watanabe heritable hyperlipidaemic (WHHL) rabbits of 2, 6 and 12 months of age, with normolipidaemic heterozygous WHHL rabbits as controls. 2. In the rings of WHHL rabbit aortae and coronary arteries preconstricted with vasoconstrictors, endothelium-dependent relaxation in response to ACh was attenuated with age compared to the heterozygous WHHL rabbits. A significant negative correlation was found between the total cholesterol content and the relaxation response to ACh in the aortae or coronary arteries from 6 and 12 month old WHHL rabbits. 3. In the rings of basilar arteries, endothelium-dependent relaxations to ACh were not modified with age. Similarly, in the rings of renal arteries, the relaxation response to ACh was not changed with age, but in the 6 and 12 month preparations, after the age of 6 months, a contraction following the relaxation appeared at higher concentrations of ACh (10?7 to 10?6 mol/L). The contraction was endothelium-dependent and inhibited by indomethacin. 4. A 23187-induced endothelium-dependent relaxations were also markedly attenuated in the aorta and significantly in the coronary artery with age. 5. Endothelium-independent relaxation to sodium nitroprusside was not changed in all arteries from WHHL rabbits of different ages. 6. These findings indicate that in the aorta and coronary artery of the WHHL rabbit, the endothelium-dependent relaxation to ACh and A 23187 becomes impaired with increasing age (i.e., with the progression of cholesterol deposition in the arterial wall) but is preserved in the basilar and renal artery.  相似文献   
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