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51.
作者对结节性甲状腺肿及其非典型结节与甲状腺癌细胞核直径、面积及 DNA 含量检测,发现核直径与面积的(?)和 S 为甲状腺癌组>非典型结节组>对照组(P<0.01);随着细胞增生异型程度的加重,核直径、面积及离散程度随之增加、DNA 含量也显著增加,显示Ⅲ级 DNA 含量细胞出现频率越高恶性的可能性就越大;同时发现各组细胞核不同 DNA 含量的核直径、面积均明显增加,与对照组相比差异生非常显著(P<0.01)。  相似文献   
52.
刘鑫  刘岚 《中国医学伦理学》2003,16(1):44-44,47
功能性矫治器是正畸临床中常用的一种矫治器,作者从口腔正畸学理论基础出发,探讨了功能性矫治器在正畸矫治作用中存在的伦理道德问题,主要有(1)不能正确的诊断、制定周密的矫治计划。(2)操作不规范、不细致、缺乏敬业精神。(3)态度简单,粗曝,缺乏与患者良好的交流。并提出解决方法(1)刻苦学习专业知识,不断提高诊疗水平及个人修养。(2)建立高度的道德责任感,以严谨的作风,规范的操作为病人服务。(3)尊重、善待青少年,建立良好的医患关系。  相似文献   
53.
 目的建立大鼠脑多梗死性痴呆(MID)模型及观察指标,评价药物对该模型的作用。方法采用从颈外动脉逆行注入微血栓颗粒的方法,制备MID模型,通过对术后大鼠的苏醒时间测定、倾斜板实验、神经症状评分3个方面评价动物的一般状态;采用大鼠穿梭箱实验、水迷宫实验检测各组大鼠学习记忆能力;并测定脑中丙二醛(MDA)的含量及超氧化物歧化酶(SOD)的活性,考察MID大鼠的行为学异常以及其作用机制。结果MID大鼠与正常组、假手术组比较,苏醒时间明显延长,在倾斜板上停留的时间显著变短,神经症状评分有显著差异;穿梭箱实验中电击时间明显延长,水迷宫实验学习记忆潜伏期延长;同时脑组织中MDA含量明显升高,SOD活力显著降低。给予药物氢化麦角碱(商品名:喜得镇)治疗后症状有所改善。结论该造模方法能显著造成大鼠脑多梗死性痴呆的多项体征,符合临床病理过程,为进一步判定一些药物是否具有治疗MID的前景打下基础。  相似文献   
54.
BACKGROUND AND PURPOSE: Etanercept (Enbrel), a recombinant tumor necrosis factor receptor fusion protein, has been shown to be effective in the treatment of patients with rheumatoid arthritis (RA). The purpose of this study was to compare the efficacy and safety of etanercept in combination with methotrexate (MTX) and MTX alone in Taiwanese patients with active RA. METHODS: In this double-blind study, 58 patients with active RA who were maintained on MTX therapy at a stable dose of 12.5 to 20 mg per week for 4 weeks were randomized to receive either etanercept 25 mg (n = 29) or placebo (n = 29) by subcutaneous injection twice weekly over a period of 12 weeks. The primary endpoint was the reduction of tender and swollen joint counts by 20% (ACR 20), 50% (ACR 50), and 70% (ACR 70) as determined by the American College of Rheumatology criteria at the 12th week. RESULTS: The addition of etanercept to MTX resulted in a greater reduction in the number of tender (7.00 vs 2.45, p = 0.012) and swollen joints (8.55 vs 3.86, p = 0.017), and in serum levels of C-reactive protein (1.26 mg/dL vs 0.45 mg/dL, p = 0.014) compared to MTX alone after 12 weeks of therapy. In addition, the global assessment of disease activity by both physicians and patients, duration of morning stiffness, pain visual analog scale score, and Health Assessment Questionnaire were all improved by etanercept plus MTX therapy. Results for the overall improvement in disease activity assessed by ACR 20 (90% vs 34%), ACR 50 (66% vs 10%) and ACR 70 (24% vs 0%) all favored the etanercept plus MTX group. However, the adverse events were comparable between the 2 treatment groups. CONCLUSION: Etanercept in combination with MTX was well tolerated and provided significantly more clinical benefit than MTX alone in Taiwanese patients with active RA.  相似文献   
55.
腓肠内外侧血管解剖特点及其在小腿创伤修复中的意义   总被引:3,自引:0,他引:3  
目的:为小腿创伤皮瓣移植修复与腓肠内、外侧血管吻合提供解剖学基础。方法:在70侧成人下肢标本上解剖观测了腓肠内、外侧血管的长度、外径、血管神经的毗邻关系及其形态特点。结果:①腓肠内、外侧动脉起于动脉,伴行静脉注入静脉;②动脉起点至入肌段的长度内、外侧分别为4.1±0.7(1.8~6.4)cm、3.7±0.5(2.0~6.5)cm;③肌门处内、外侧动脉的外径分别为2.2±0.1(1.1~3.4)mm、2.0±0.1(0.9~3.1)mm;④肌门处伴行静脉有1~2条,内、外侧静脉外径为2.5±0.3(1.8~4.5)mm,2.3±0.3(1.5~4.1)mm。结论:腓肠内、外侧血管恒定、径粗、较长,是小腿创伤皮瓣移植修复受区可供应用的吻合血管  相似文献   
56.
全身麻醉插管术后院内获得性肺部感染探讨   总被引:17,自引:3,他引:14  
全身麻醉气管插管术后下呼吸道感染具有较高发生率。分析526例手术时间超过4小时普外科病例,经u检验发现全身麻醉气管插管术后患者肺部感染率明显高于持续性硬膜外麻醉术后患者,影响因素主要与全麻插管用具及麻醉机消毒情况有关,也与术前存在慢性阻塞性肺部疾患和术后保留气管插管有关。降低全麻术后肺部感染应重视无菌操作,尽可能对麻醉机管道进行常规消毒。  相似文献   
57.
膳食纤维分析方法的简化   总被引:14,自引:0,他引:14  
郑建仙  耿立萍 《营养学报》1997,19(2):207-211
对SelvendranRR等人的冷中性洗涤剂纤维提取分析法(CNDF)进行简化,改变了各溶剂的处理时间,省去了湿球研磨与超声波处理步骤。将原法中SLS-PAW-DWSO处理时间15h,30min和16h分别延长为22h,40min与22h,化学分析与透射电镜观察结果表明,简化法对膳食纤维的提取分析效果与原推荐法相同,更加方便与实用。  相似文献   
58.
Summary Using acetylcholinesterase histochemical and choline acetyltransferase immunocytochemical localization methods, this study has provided conclusive evidence for the existence of cholinergic neurons in the external cuneate nucleus of gerbils. By light microscopy, both acetylcholinesterase and choline acetyltransferase labelling was confined to the rostral portion of the external cuneate nucleus. Ultrastructurally, acetylcholinesterase reaction products were found in the nuclear envelope, cisternae of rough endoplasmic reticulum and Golgi saccules of some somata and large dendrites as well as in the membranes of small dendrites, myelinated axons and axon terminals. These neuronal elements were also stained for choline acetyltransferase; immunoreactivity was associated with nuclear pores, nuclear envelope, perikaryal membrane and all the membranous structures within the cytoplasm. Of the total choline acetyltransferase-labelled neuronal profiles analysed, 79% were myelinated axons, 15% dendrites, 4% somata and 2% axon terminals. The immunostained axon terminals consisted of two types containing either round (Rd type; 62.5%) or pleomorphic (Pd type; 37.5%) vesicles. Both were associated directly with choline acetyltransferase-positive dendrites. In contrast to the paucity of choline acetyltransferase-labelled axon terminals, numerous choline acetyltransferase-positive myelinated axons were present. It may thus be hypothesized that most, if not all, of the external cuneate nucleus cholinergic neurons are projection cells; such cells may give rise to axonal collaterals which synapse onto their own dendrites for possible feedback control. Choline acetyltransferase-positive dendrites were contacted by numerous unlabelled presynaptic boutons, 60% of which contained round or spherical synaptic vesicles (Rd boutons) and 40% flattened vesicles (Fd boutons), suggesting that these neurons are under strong inhibitory control. The preferential concentration of cholinergic components in the rostral external cuneate nucleus may be significant in the light of the highly organized somatotopy in the external cuneate nucleus and its extensive efferent projections to medullary autonomic-related nuclei. Our results suggest that the cholinergic neurons may be involved in somatoautonomic integration.  相似文献   
59.
自Messerldinger 1972年开始采用鼻内镜手术治疗慢性鼻窦炎至今已近40年[1],在我国也已经有20年的历史.1995年Kennedy将其命名为功能性内镜鼻窦手术(functional endoscopic sinus surgery,FESS)[2].时至今日,FESS仍然是慢性鼻窦炎最重要的治疗手段之一.  相似文献   
60.
Inhalation anesthetics are effective chemical preconditioning agents in experimental cerebral ischemia. However, previous work has been performed exclusively in male animals. We determined if there is a gender difference in ischemic outcome after isoflurane preconditioning (IsoPC), and if this sex-specific response is linked to differences in Akt phosphorylation or expression of neuronal inducible cell-death putative kinase (NIPK), a negative modulator of Akt activation. Young and middle-aged male and female mice were preconditioned for 4 h with air (sham PC) or 1.0% IsoPC and recovered for 24 h. Cortices were subdissected from preconditioned young male and female mice for measurement of Akt phosphorylation (Western blot) and NIPK mRNA (quantitative polymerase chain reaction). Additional cohorts underwent 2 h of reversible middle cerebral artery occlusion. Lastly, male and female Akt1(+/+) and Akt1(-/-) mice were studied to determine if gender differences in ischemic outcome after IsoPC is Akt1-dependent. Infarction volume was determined at 22 h reperfusion (2,3,5-triphenyltetrazolium chloride). As expected, IsoPC decreased ischemic damage as compared with sham PC in young and middle-aged male mice. In contrast, IsoPC markedly increased infarction in young female mice and had no effect in middle-aged female mice. Cortical phospho-Akt was increased by IsoPC versus sham PC only in male mice. No increase was observed in IsoPC female mice. NIPK mRNA was higher in female mice than in male mice regardless of preconditioning status. Male IsoPC neuroprotection was lost in Akt1-deficient male mice. We conclude that IsoPC is beneficial only in ischemic male brain and that sex differences in IsoPC are mediated through Akt activation and basal NIPK expression.  相似文献   
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