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71.
Summary This study evaluates healing fractures of the femoral neck in dogs by using standard radiography, intraosseous venography, India ink staining and histology.The 45 animals were divided into three groups, one of which was not treated, but in the other two the fracture was fixed with a screw or two Kirschner wires.Our results suggest that, when intraosseous venography was positive, India ink injection was also positive, and the late phase of fracture healing was reached.
Résumé Etude de la consolidation des fractures du col fémoral chez le chien à l'aide des radiographies standard, de la phlébographie osseuse, de la coloration par l'encre de Chine et de l'examen anatomopathologique. Les animaux ont été divisés en trois groupes, dans l'un la fracture n'a pas été traitée, dans les deux autres elle a été fixée soit par une vis, soit par deux broches de Kirschner. Les résultats tendent à montrer que lorsque la phlébographie est positive, la coloration par l'encre de Chine l'est également et que la phase ultime de la consolidation est atteinte.
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72.
【目的】制备和鉴定 β1受体亚型特异性抗体。【方法】人工合成 β1受体细胞膜外第二环 197 2 2 2位氨基酸序列作为抗原。连接钥孔冒贝血蓝蛋白 (KLH)增加抗原性后免疫兔获得抗血清。通过凝胶双扩散实验和ELISA法鉴定其效价 ;通过免疫荧光法及ELISA法鉴定其特异性 ;通过离体蛙心灌流实验鉴定其药理活性。【结果】该抗血清效价高 (分别为 1∶6 4和 1∶10 6)、特异性强 ,能和心肌 β1受体发生特异性结合 (1∶10 4 ~ 1∶10 5) ,为异丙肾上腺素的非竞争性拮抗剂。 (pD2 ′ =1 6 2 )。【结论】成功制备的 β1受体亚型特异性抗体可能成为进一步研究 β1受体分布、功能和定量的有力工具。  相似文献   
73.
【目的】了解手术创伤对术后全身炎症反应综合征 (SIRS)的影响。【方法】搜集外科重症监护室 (SICU) 335例患者的术后资料 ,分析不同手术组SIRS发病率 ;手术时间、失血量与SIRS持续时间的关系 ;SIRS持续时间与术后并发症的关系。【结果】术后SIRS发病率为 75 8% ,大手术高达 92 4 % ;无并发症患者失血量与SIRS持续时间呈正相关 (r1=0 783,P<0 0 1) ,手术时间与SIRS持续时间呈正相关 (r2 =0 398,P <0 0 1) ;随着SIRS持续时间延长 ,并发症发病率显著增高 (P<0 0 5 )。【结论】术后SIRS发生、发展与手术创伤密切相关 ;监测SIRS进程有助于及早发现并发症  相似文献   
74.
目的 :研究肺癌组织中第 3号染色体短臂 (3P)和第 9号染色体短臂 (9P)上微卫星标志物的改变与肺癌发生发展的关系。方法 :应用聚合酶链反应 (PCR)结合微卫星银染法检测 5 6例肺癌和 2 3例良性肺部病变 3P和 9P上的微卫星标志物的改变。结果 :5 6例肺癌组织标本中 3P上有微卫星改变 2 6例 ,检出率 46% ,9P上有微卫星改变的 2 3例 ,检出率为 41% ,5 6例肺癌组织中 ,3P和 9P上有微卫星改变的 3 9例 ,检出率 69 6% ,2 3例肺部良性疾病组织中均未出现微卫星标志物改变。肺癌组织标本中 3P上的微卫星改变与肺癌的分化程度有关 ,低分化肺癌的微卫星改变较高、中分化肺癌的微卫星改变明显增多 (P <0 .0 1)。而 9P上的微卫星改变与淋巴结转移有关 ,有淋巴结转移的肺癌组织标本上微卫星改变较不伴淋巴结转移的微卫星改变检出率明显增多 ,(P <0 .0 5 )。结论 :3P和 9P上的微卫星改变与肺癌发生、发展和转移密切相关 ,检测肺癌组织 3P和 9P上的微卫星改变对肺癌的早期诊断和判断有无淋巴结转移有一定的价值  相似文献   
75.
Serine hydroxymethyltransferase (SHMT) provides activated one-carbon units required for the biosynthesis of nucleotides, protein, and methyl group by converting serine and tetrahydrofolate to glycine and N(5),N(10)-methylenetetrahydrofolate. It is postulated that SHMT activity is associated with the development of methotrexate resistance and the in vivo activity of SHMT is regulated by the binding of N(5)-CHO-THF, the rescue agent in high-dose methotrexate chemotherapy. The aim of this study is to advance our understanding of the folate-mediated one-carbon metabolism in zebrafish by characterizing zebrafish mitochondrial SHMT. The cDNA encoding zebrafish mitochondrial SHMT was cloned, overexpressed in Escherichia coli, and purified with a three-step purification protocol. Similarities in structural, physical, and kinetic properties were revealed between the recombinant zebrafish mitochondrial SHMT and its mammalian orthologs. Surprisingly, leucovorin significantly inhibits the aldol cleavage of serine catalyzed by zebrafish cytosolic SHMT but inhibits to a lesser extent the reaction catalyzed by the mitochondrial isozyme. This is, to our knowledge, the first report on zebrafish mitochondrial folate enzyme as well as the differential inhibition of leucovorin on these two SHMT isoforms. Western blot analysis revealed tissue-specific distribution with the highest enrichment present in liver for both cytosolic and mitochondrial SHMTs. Intracellular localization was confirmed by confocal microscopy for both mitochondrial and cytosolic SHMTs. Unexpectedly, the cytosolic isoform was observed in both nucleus and cytosol. Together with the previous report on zebrafish cytosolic SHMT, we suggest that zSHMTs can be used in in vitro assays for folate-related investigation and antifolate drug discovery.  相似文献   
76.
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric cancer.  相似文献   
77.
78.
复杂主动脉病变的腔内血管外科治疗   总被引:3,自引:1,他引:2  
目的 探讨复杂主动脉病变的腔内血管外科治疗方法。方法 对21例合并有内脏动脉缺血等复杂的主动脉病变,双球管定位下经锁骨上动脉到股动脉交换导丝以确保真腔内植入带膜支架,对真腔完全被假腔压闭的患者采取真腔内加压推进以通过导丝,用超长带膜支架来封堵大破口治疗夹层合并巨大假性动脉瘤形成,对夹层合并腹主动脉瘤患者采取血管腔内技术联合开腹手术等方法。结果 术后内漏3例,其中2例7 d后停止,1例漏血持续存在。3例主动脉创伤术后完全康复,余18例复杂主动脉夹层术后即时造影示瘘口已被完整覆盖,假腔无血漏入,内脏动脉等恢复真腔供血。18例中6例合并肠管缺血,3例合并肾动脉缺血,3例肠管缺血、肾动脉缺血,2例腹主动脉真腔完全被假腔压迫,以及2例合并下肢缺血术后均逐渐恢复,无脏器及肢体缺血坏死发生。2例合并腹主动脉瘤夹层行支架型人工血管封闭夹层破口后行开腹手术切除腹主动脉瘤、人工血管置换。16例随访5~36个月,平均22.3月,1例内漏持续存在,但假腔未继续加大,其余患者存活良好。结论 对复杂的主动脉病变的治疗,通过对腔内血管外科技术进行改进,并适当结合传统手术方法,使某些过去被认为不能够治疗的复杂主动脉病变可得以成功治疗。  相似文献   
79.
The influence of age on the regional arterial and venous effects of serotonin (5-HT) was investigated in 13 young (aged 22-31 years) and seven older (aged 50-69 years) healthy volunteers. Single-dose infusions of 5-HT (1, 10, and 80 ng/kg/min) and of the 5-HT2 receptor antagonist ritanserin (50, 150, and 500 ng/kg/min) were administered into the brachial artery. Subsequently, the relative arterial and venous effects of the highest dose of 5-HT were investigated. Forearm blood flow (FBF) and maximum venous outflow (MVO) were measured by venous occlusion plethysmography. Heart rate (HR) and intraarterial (i.a.) blood pressure were recorded semicontinuously. In both age groups, 5-HT induced an initial transient arterial dilation, followed by a persistent increase in FBF for the doses of 1 and 10 ng/kg/min and a relative small decrease in FBF for the highest dose. In both age groups, the highest dose of 5-HT induced a similar large reduction in MVO (p less than 0.05 for both). The reduction in MVO was attenuated by ritanserin (500 ng/kg/min, p less than 0.05 for both groups). In the younger subjects, this dose of ritanserin also unmasked an arterial dilator effect of the highest dose of 5-HT (p less than 0.05). The single infusions of ritanserin did not influence FBF significantly in either study group. No significant differences were observed between the age groups. These results show that in the forearm of healthy subjects arterial and venous vascular responses to 5-HT were not age-related. In the arterial vascular bed, 5-HT acted predominantly as a vasodilator; at high doses, mainly venous vasoconstriction was observed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
80.
BACKGROUND AND PURPOSE: This study investigated the characteristics of intussusception in Taiwanese children of different age groups, including the incidence, length of hospitalization and hospital costs. METHODS: Children with a diagnosis of intussusception who were hospitalized from 1999 through 2001 were identified from a nationwide health insurance claims database. The incidence of intussusception was calculated by age, gender, and season. Length of hospitalization and hospital costs were also analyzed. RESULTS: A total of 6988 cases of intussusception were identified in Taiwan from 1999 to 2001. Among them, 4859 cases occurred in children below 15 years of age. The average incidence among children below age 15 years was 34.5 per 100,000, with a peak incidence of 118.8 per 100,000 observed among children younger than 24 months old. The highest incidence of intussusception in Taiwanese children occurred between 12 and 24 months of age. According to the data for patients below 15 years of age hospitalized for intussusception in year 2000, males were more likely to be affected than females (61.3% vs 38.7%). Intussusception-related hospitalizations were rare in infants in the first few months of life, increased in those 6 to 12 months old, and peaked among children 1 to 3 years old. Among the 952 patients with intussusception admitted to hospitals in 2000, 297 (31.2%) received surgery, incurring higher median medical costs (New Taiwan Dollars [NT dollars] 42,265 or US dollars 1234) and longer median hospital stay (6.2 days) than the 655 patients who did not require surgery (NT dollars 6290 or US dollars 185 for hospitalization of 2.4 days). CONCLUSIONS: The study found that the incidence of intussusception peaked in the second year of life in Taiwanese children. There was also a male predominance and lack of seasonal variation in incidence.  相似文献   
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