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81.
82.
目的:探讨经颅多谱勒超声(TCD)在颈椎病(椎动脉型)所致位置性缺血性眩晕中的诊断价值.方法:利用TCD对颈椎病所致位置性缺血性眩晕76例患者进行双侧大脑后动脉(PCA)的平均血流速度分析,并结合转颈试验,探测双侧PCA平均血流速的动态变化情况.结果:颈椎病所致位置性缺血性眩晕患者当头侧向转动时,双侧PCA的平均血流速度暂时性降低,当头转回中立位时,平均血流速度逐渐回升.结论:TCD有助于识别位置性眩晕中的真性位置性缺血患者,是一种无创、简便、价廉、可靠,并可床旁操作和提供实时动态血流动力学资料的重要检查方法. 相似文献
83.
84.
内蒙古自治区智力残疾现患率调查及病因分析 总被引:1,自引:0,他引:1
目的:了解内蒙古自治区智力残疾(mental retardation.MR)的现患率及其分布特点,分析其主要致残原因构成特点,探讨预防治疗措施。方法:采用概率比例、多阶段分层整群抽样方法进行现况调查及病例对照研究,根据年龄分别使用丹佛发育筛查测验及《7岁以上人群残疾筛查问卷》筛查,分别使用Gesell发育诊断量表及韦氏儿童智力量表简式(WISC-CR),韦氏成人智力量表简式(WAIS-RC)进行智力诊断,采用SPSS11.0软件对数据进行统计分析。结果:①内蒙古自治区智力残疾患者的现患率为4.95‰,男性MR现患率高于女性(χ2=6.28,df=1,P<0.05),农村MR的现患率明显高于城市(χ2=60.035,df=1,P<0.01)。②内蒙古自治区智力残疾致残原因以疾病(29.26%)和遗传因素(23.79%)为主。③在18岁之前(智力发育期)发现智力残疾的占74.53%,且以0~3岁发现智力残疾的人数比例最高(48.84%)。结论:智力残疾的防治重点应在农村,预防应以疾病(主要包括脑疾病、内分泌障碍、惊厥性疾病)及遗传因素为主。强调早期发现、早期干预。 相似文献
85.
目的观察低浓度表面活性剂聚氧乙烯蓖麻油,Labrasol和聚山梨酯80对肠黏膜P-gp的调控作用。方法使用体外扩散池法评价罗丹明123(R123)经空肠、回肠和结肠黏膜的经时经吸收方向和分泌方向的透过量和透过系数(Papp),并测定不同浓度表面活性剂对R123和荧光素钠(CF)经肠黏膜透过性的影响。R123和CF在接受室中的浓度用荧光分光光度法测定。结果R123经肠道黏膜的透过性存在部位差,即以空肠、回肠和结肠的次序透过性依次减少。另一方面,R123经肠道分泌方向的透过性显著地高于其吸收方向的透过性。低浓度的CEL和Labrasol可显著增强R123经吸收方向的透过性,减少经分泌方向的透过性;而低浓度的聚山梨酯80可显著增强R123经吸收方向的透过性,但对经分泌方向的透过性无显著影响。但实验浓度的表面活性剂对CF的肠道转运没有影响。结论低浓度的聚氧乙烯蓖麻油、Labrasol和聚山梨酯80可通过对P-gp功能的抑制而用于改善受P-gp介导药物的吸收,有望提高此类药物的口服生物利用度。 相似文献
86.
CARLO LA VECCHIA SILVIA FRANCESCHI FABIO PARAZZINI ELENA COLOMBO FABIO COLOMBO ALESSANDRO LIBERATI COSTANTINO MANGIONI 《BJOG : an international journal of obstetrics and gynaecology》1983,90(7):654-661
Summary. Between 1970 and 1976, 290 patients with endometrial cancer were treated at the 1st Obstetrics and Gynecology Clinic of the University of Milan. The median age was 62 years. Surgery was completed in 262 (90.3%) patients. Abdominal hysterectomy was used in 158 (70.9%) stage I and 40 (71.4%) stage II/III patients; vaginal hysterectomy in 55 (24.7%) stage I and nine (16.1%) stage II/III patients. Resection of the upper vagina was performed in 168 patients. Postoperative external beam radiotherapy was used in stage II/III patients and in 44 (19.7%) stage I high-risk patients. Ten-year survival, determined by the life-table method, was 84.8% in stage I (223 patients), 53.4% in stage II (37 patients), 64.4% in stage III (19 patients), and 9.1% in stage IV (11 patients). Factors associated with poorer prognosis were: late age at diagnosis (P<0.001); deep myometrial invasion (P<0.001); poorly differentiated histological grade ( P =0.11); lack of resection of the upper vagina ( P = 0.13). The role and importance of surgery is discussed, with special emphasis on the selective use of the vaginal route in aged, obese and medically high-risk patients. 相似文献
87.
Influence of margin design and taper abutment angle on a restored crown of a first premolar using finite element analysis 总被引:5,自引:0,他引:5
Proos KA Swain MV Ironside J Steven GP 《The International journal of prosthodontics》2003,16(4):442-449
PURPOSE: The purpose of this study was to determine the influence of margin design and taper abutment angle on the stresses developed in all-ceramic first premolar crowns. MATERIALS AND METHODS: Four margin designs and three taper abutment angles were independently incorporated into models examined by finite element analysis. A 600-N force was applied vertically downward. RESULTS: The taper abutment angle had a significant influence on the greatest peak tensile maximum principal stresses (sigma11) in the coping (16.8% change in stress for an 8-degree variation in taper angle). The margin design had significant influence on the highest peak tensile sigma11 in the dentin (60% difference in stress between designs) and lesser significance in the cement (30%). All calculated values of the highest peak tensile sigma11 were considerably lower than the fracture strengths of the respective materials in which the stresses resided. CONCLUSION: A smaller taper abutment angle and a larger chamfer radius (equivalent to the modified light chamfer) are recommended to reduce the magnitude of the greatest peak tensile sigma11 based on the finite element modeling conducted. 相似文献
88.
Influence of cement on a restored crown of a first premolar using finite element analysis 总被引:7,自引:0,他引:7
Proos KA Swain MV Ironside J Steven GP 《The International journal of prosthodontics》2003,16(1):82-90
PURPOSE: The purpose of this study was to examine the influence of the elastic modulus of cement and luting thickness on the resulting stresses in an axially loaded crown cemented onto a first premolar. A comparison of these stresses was also made with the strength of the constituent materials making up the crown. MATERIALS AND METHODS: Examination of the stresses on a restored crown was conducted using finite element analysis. Eight different axisymmetric models containing combinations of In-Ceram or gold coping, using adhesive resin or zinc phosphate cement as the luting agent, with thicknesses of either 0.05 or 0.1 mm were analyzed. RESULTS: The peak tensile principal stresses in the porcelain remained below its material fracture strength. The same was true for the peak stress in the adhesive resin compared to its fracture and chemical bond strength. This was not the case for zinc phosphate. The influence of the luting agent's elastic modulus on the stresses in the crown was minor, and the influence of luting thickness was even less. CONCLUSION: The role of the luting agent was primarily one that effectively transferred the resulting stresses between the relatively stiff coping and underlying dentin. There was no evidence of the luting agent itself playing a significant role in resisting deflection from the applied force. 相似文献
89.
综述近5年中医治疗糖尿病肾病在病因病机、辨证论治及实验研究方面取得的进展,提出了其存在的问题并分析了对策。 相似文献
90.
目的探讨米非司酮对VEGF-165在子宫腺肌症中表达的影响。方法43例子宫腺肌症患者分为对照组(n=21)和米非司酮治疗组(n=22),采用放射免疫法测定对照组(月经第3天)和米非司酮组(术前)血清中FSH、LH、E2、PRL、P及T的水平。采用免疫组化法测定两组患者在在位和异位子宫内膜中的VEGF-165蛋白水平。结果米非司酮组较对照组血清FSH、LH、E2、P明显降低(P<0.05),而血清PRL和T的水平两组间无统计学差异(P>0.05)。VEGF-165在子宫内膜腺上皮细胞内的表达,异位内膜均明显高于在位内膜(P<0.05);而其在间质细胞内的表达,异位内膜与在位内膜无统计学差异(P>0.05)。米非司酮组异位和在位内膜腺上皮细胞、间质细胞中VEGF-165的表达水平均较对照组明显降低(P<0.05)。VEGF-165在对照组异位内膜腺上皮细胞中的表达,增殖期高于分泌期(P<0.05)。结论米非司酮治疗后,VEGF-165在异位和在位内膜中的表达明显下降,可能是通过抑制VEGF蛋白合成,降低血管通透性,抑制新生血管生成,从而有效地控制子宫内膜异位症的发生发展。 相似文献