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71.
牙周炎是口腔常见病、多发病,是牙齿松动的主要原因之一.牙周夹板一直以来是松牙固定的有效手段,它可以将多个牙连成一个整体,形成一个“多根巨牙”,共同承担咬合力,有效地分散牙周膜及牙槽骨的应力,为牙周组织的愈合创造有利条件.三维有限元分析法是研究复杂模型应力分布的生物力学方法,近年来广泛应用于牙周夹板的研究中,该方法可以逼...  相似文献   
72.
The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL.  相似文献   
73.
目的 探讨雾化吸入全程中行为干预对学龄期喘息儿童的治疗效果的影响.方法 将141例学龄期喘息儿童于雾化过程中按是否自愿接受行为干预分为实验组75例和对照组66例,2组患儿雾化前均进行喘息知识认知和"呼吸"指导.实验组在此基础上由专科人员陪护整个吸入过程且进行"呼吸"、吞咽唾液或用鼻呼气、握持雾化罐、保持体位等行为干预.比较2组患儿雾化结束后肺部哮鸣音及患儿主诉是否改善、经皮测血氧饱和度以及患儿依从性的差异.结果 雾化完成后实验组患儿主诉较雾化前舒服73例占97.3%,SaO_2>95%69例占92.0%;而对照组主诉较雾化前舒服53例占80.3%,SaO_2>95%50例占75.8%,差异显著;实验组平静呼吸哮鸣音改善情况和医嘱依从情况与对照组相比差异显著.结论 雾化吸人全程中持续行为干预能显著提高喘息儿童雾化吸入的效果和吸入治疗依从性.  相似文献   
74.
原发性附睾肿瘤——附42例报告   总被引:3,自引:1,他引:3  
目的探讨原发性附睾肿瘤的临床特点、病理类型及临床诊治方法。方法回顾性总结42例接受手术治疗的原发性附睾肿瘤患者临床资料。42例附睾肿瘤中良性肿瘤37例(88.1%),其中附睾腺瘤样瘤21例,平滑肌瘤9例,纤维假瘤2例,其余5例分别为乳头状囊腺瘤、血管平滑肌脂肪瘤、纤维瘤、纤维脂肪瘤和硬化性m管瘤。恶性肿瘤5例(11.9%),为附睾腺癌2例,非霍奇金淋巴瘤、横纹肌肉瘤和平滑肌瘤肉瘤变各1例。良性肿瘤作单纯肿瘤或患侧附睾切除,恶性肿瘤(除平滑肌瘤肉瘤变患者外)行根治眭附睾睾丸切除术,术后辅助放和/或化疗。结果良性肿瘤27例获随访,预后良好,术后无复发。恶性肿瘤5例均获随访,预后差,2例腺癌患者均于术后12个月死亡,横纹肌肉瘤患者术后20个月时广泛转移,非霍奇金淋巴瘤患者和平滑肌瘤肉瘤变患者健在。结论附睾肿瘤大部分为良性,手术切除效果好。恶性肿瘤少见,但预后较差,综合治疗可能会提高疗效。  相似文献   
75.
目的 探讨术前动脉灌注化疗对进展期结直肠癌的远期临床疗效.方法 选择ⅡB、Ⅲ期的结直肠癌患者128例,随机分为2组:试验组68例行术前动脉灌注化疗,方案为:奥沙利铂(艾恒)130mg/m2、羟基喜树碱20 mg/m2、氟脲苷600 mg/m2,经股动脉插管灌注化疗1、2次,8~14 d后接受手术治疗;对照组60例直接手术治疗.观察动脉灌注化疗不良反应及组织学疗效,比较2组手术切除率、手术并发症、术后病理分期及远期生存率.结果 试验组动脉灌注化疗不良反应主要表现为胃肠道反应和骨髓抑制,均属Ⅰ、Ⅱ度.试验组手术切除率为97.1%(66/68)、根治性切除率为96.9%,分别高于对照组的73.3%(44/60)和79.5%(x2=14.848、8.906,P均<0.05);试验组组织学有效率达72.7%,病理分期均较术前降低,其中Ⅱ期病例明显较对照组增多(P<0.05);试验组中位生存期为53.0个月,1、3、5年生存率分别为95.3%、85.9%、44.6%;对照组的中位生存期为42.0个月,1、3、5年生存率分别为92.6%、75.9%、22.0%,试验组生存率高于对照组,但只有5年生存率差异具有统计学意义(x2=6.385,P<0.05).术后并发症2组比较差异无统计学意义(P>0.05).结论 术前动脉灌注化疗对进展期结直肠癌降低临床分期、提高手术切除率尤其是根治性切除率作用和疗效确切,并能提高患者的远期生存率.
Abstract:
Objective To evaluate the curative effect of neoadjuvant chemotherapy via arterial infusion on advanced colorectal carcinoma. Methods One hundred and twenty-eight advanced colorectal carcinoma patients in stage Ⅱ B or Ⅲ were randomly divided into 2 groups. Sixty-eight cases received preoperative arterial infusion chemotherapy( the treatment group),and chemotherapy regimen consist of Oxaliplatin(L-OHP) 130 mg/m2, Hydroxycamptothecin (HCPT) 20 mg/m2 and Dexifluridine (FUDR)600 mg/m2. Femoral arterial infusion chemotherapy administrated 8 ~ 14 days preoperative. Sixty cases received surgery directly(the control group). The adverse reaction and histology effect after arterial infusion chemotherapy were observed, and resection rate,complications,pathology stage,together with long term survival were compared. Results Adverse reaction were mostly grade Ⅰ -Ⅱ gastrointestinal discomfort and bone marrow depression with arterial infusion chemotherapy. Resection rate was 97. 1% (66/68) ,and 64 cases(96. 9%) underwent raclical (R0) resection in the treatment group, which were higher than those in the the control group(73. 3%(44/60) and 79. 5%,respectively) (x2 = 14. 848,8. 906, Ps < 0. 05). Histology effect of the treatment group was 72. 7%, and the pathology stage downstaged compared to preopeartion. Percent of patients in stage Ⅱ in the treatment group was higher than that in the control group( P < 0. 05). The median survival time of test group was 53. 0 months, 1- ,3-,and 5-year survival rates were 95.3%,85.9% and 44.6%, respectively. In the control group, the median survival time was 42.0 months, 1-, 3-, and 5-year survival rates were 92.6%, 75.9% and 22.0%,respectively. There was significant difference in 5-year survival rate(x2 = 6. 385, P < 0. 05). No difference in postoperative complications between two groups(P > 0. 05). Conclusion The neoadjuvant chemotherapy via arterial infusion is of great significance on downstnging the pathology of advanced colorectal carcinoma, raising the excision rate, especially radical resection, and long term survival rate.  相似文献   
76.
目的:探讨人血管内皮生长因子165基因(hVEGF165)联合间充质干细胞(mesenchyma1stemce11s,MSCs)治疗对扩张型心肌病胶原重塑的影响。方法:将40只扩张型心肌病(DCM)大鼠模型随机分为4组:PBS组、MSCs心肌移植联合基因治疗组(MSCs—GENE组)、MSCs心肌移植组(MSCs组)以及基因治疗组(GENE组)。心肌局部注射所构建MLC-2v/pIRES2-EG-FP-hVEGF165与MSCs,采用逆转录-聚合酶链反应(RT—PCR)检测I型、Ⅲ型胶原和转化生长因子-β(TGF-β)基因表达,蛋白免疫印迹(Westrenb1ot)检测hVEGF165蛋白表达。结果:PBS组、MSCs+GENE组、MSCs组以及GENE组的I型胶原PCR产物灰度比分别为(0.359±0.010)、(0.240±0.012)、(0.313±0.058)、(0.230±0.011);而Ⅲ型胶原分别为(0.831±0.011)、(0.842±0.015)、(0.917±0.058)、(0.688±0.015);TGF-β1分别为(0.548±0.067)、(0.370±0.012)、(0.561±0.014)、(0.369±0.098);MSCs+GENE组TGF-81与GENE组比较差异无统计学意义,但两者显著低于PBS组和MSCs组,提示TGF-β1表达下调;I型/III型胶原灰度比分别为(0.436±0.072)、(0.290±0.023)、(0.337±0.021)、(0.333±0.011),其中MSCs组与GENE组比较差异无统计学意义;MSCs组与GENE组的I型/III型胶原灰度比减低,2组比较差异无统计学意义,但MSCs—GENE组进-步使I型/III型胶原灰度比减低;TGF-β1表达分析结果显示,hVEGF165基因治疗较MSCs移植使TGF-β1表达下调的作用更显著。结论:MSCs移植与hVEGF165基因治疗有可能通过下调TGF-β1表达,降低I型/III胶原比值,增加心肌顺应性,减轻心肌胶原网络重塑而改善心功能。  相似文献   
77.
纳智  许又凯 《中国中药杂志》2009,34(18):2338-2342
目的:研究版纳藤黄Garcinia xipshuanbannaensis枝叶的化学成分.方法:利用正相硅胶、反相RP-18柱色谱及葡聚糖凝胶Sephadex LH-20等手段进行分离纯化,根据波谱数据鉴定化合物的结构.结果:分离鉴定了15个化合物,分别为bannaxanthone E(1),大叶藤黄醇(xanthochymol,2),异大叶藤黄醇(isoxanthochymol,3),环大叶藤黄醇(cycloxanthochymol,4),osajaxanthone(5),gentisein(6),mangostinone(7),山柰酚(8),槲皮素(9),牡荆素(10),2"-O-acetylvitexin(11),3-乙酰齐墩果酸(12),(-)-表儿茶素[(-)-epicatechin,13],β-谷甾醇(14),胡萝卜苷(15).结论:化合物4~9,11~13为首次从该种植物分离得到,化合物11~13为首次从该属植物分离得到.  相似文献   
78.

Purpose  

To analyse quantitatively and qualitatively asymptomatic hepatic and pancreatic involvement in hereditary haemorrhagic telangiectasia (HHT) using 64-section helical CT.  相似文献   
79.
α受体激动剂盐酸米多君治疗女性压力性尿失禁的临床研究   总被引:10,自引:1,他引:10  
目的 评价盐酸米多君 (管通 )治疗女性压力性尿失禁的有效性和安全性。 方法 采用多中心、随机、双盲、安慰剂平行对照方法对 136例女性压力性尿失禁患者进行管通与安慰剂的对比研究。试验组 6 8例 ,服管通 2 .5mg/次 ,3次 /d ,疗程 4周 ;对照组 6 8例 ,以安慰剂替代管通。  结果 完成试验 12 9例 ,,管通组 (6 6例 )平均尿失禁量减少 9.9g ,安慰剂组 (6 3例 )减少 3.1g ;管通组尿失禁等级评分减少 1.0 2分 ,安慰剂组减少 0 .35分 ;管通组的客观有效率和主观有效率分别为 6 6 .7%和 80 .3% ,安慰剂组分别为 31.7%和 33.3% ,两组比较 ,差异均有显著性意义 (P均 <0 .0 0 1)。管通组患者副作用发生率 15 .0 % ,安慰剂组 17.1% ,两组间差异无显著性意义 (P >0 .0 5 )。 结论 盐酸米多君治疗女性压力性尿失禁疗效明显 ,优于安慰剂 ,安全性和耐受性与安慰剂相似。  相似文献   
80.
BACKGROUND: CT has proved to be helpful in patients with acute pancreatitis for differentiating between mild and severe forms. Followup of acute pancreatitis with CT has been advocated but rarely studied. The aim of this study was to determine if late CT performed at day 7 might be helpful in establishing the prognosis or the type of complications, and to select a subgroup of patients in whom CT could be beneficial. STUDY DESIGN: Contrast-enhanced CT was performed at the admission day and 7 days after admission in 102 patients admitted for acute pancreatitis. The extent of pancreatic inflammation was classified according to Balthazar grade, and intrapancreatic necrosis on these examinations was prospectively assessed and compared with clinical and biologic data and with patient outcomes. RESULTS: Among 102 patients, complications developed in 24 (23%). Complications developed in only 8% of patients with Ranson score <2, making routine early CT unnecessary. For the patients with Ranson score <2 and Balthazar grades A and B at day 1 CT, late CT seemed to be useless. Complication was suspected by clinical and biologic tests before day 7 in 22 of 24 complicated patients (92%), suggesting that CT could be proposed only in cases of clinical or biologic deterioration. Late CT was correlated with a complicated course in patients with Balthazar grades D and E or intrapancreatic necrosis >50%. Late CT was predictive of complications in cases of intrapancreatic necrosis enlarging since the first examination. CONCLUSIONS: Our study showed that in acute pancreatitis: 1) there is little justification for systematic early CT, especially in patients with Ranson score <2, and 2) late CT does not need to be performed routinely, but only in cases of clinical or biologic worsening.  相似文献   
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