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41.
The aim of this study was to assess the effect of difference in tine diameter on probing pocket depth measurement. 2 sets of tines with Williams markings at 1, 2, 3, 5, 7, 8, 9 and 10 mm, and with a "round" tip, diameter 0.5 mm, were compared. One set was described as parallel-sided, the other as tapered. The parallel-sided tine was almost parallel from the 10 mm marking to the tip (tip diameter mean = 0.46 mm, 95% C.I. 0.456-0.464), while the corresponding diameter for the tapered tine varied (tip diameter mean = 0.48 mm, 95% C.I. 0.473-0.489). Calibration markings appeared highly consistent with the expected value to within 0.01 mm. The tines were mounted in Brodontic handles at 0.25 N. Examiner probing repeatability yielded kappa 0.86 for "parallel-sided" and 0.81 for "tapered" tines in vivo. 412 approximal pockets were assessed in 53 patients with routine chronic adult periodontitis, mean age 42.1 years. Each site had a probing depth of greater than or equal to 5 mm, PlI less than or equal to 1, GI less than or equal to 1, PBI less than or equal to 1. Each site was probed 2x with a 15-min interval. At the first 251 sites, the parallel-sided tine was used initially, and the tapered at the remaining 161 sites. Results indicated a highly significant tendency for the parallel-sided tine to yield a deeper reading when a difference occurred. These findings indicate that with adequate training providing high examiner repeatability, one source of error in probing data can be minimised.  相似文献   
42.
A comparison was made of the effects of continuous epidural analgesia with bupivacaine and intermittent epidural morphine on bowel function after abdominal hysterectomy. The duration of postoperative ileus was assessed as the time from the end of operation to the first postoperative passage of flatus and feces. Twenty-two patients were randomly allocated to two equal groups. An "epidural morphine" group received general anesthesia and epidural morphine for postoperative pain relief, and an "epidural bupivacaine" group was given combined general anesthesia and epidural anesthesia with 0.5% bupivacaine intraoperatively and epidural analgesia with 0.25% bupivacaine postoperatively. Epidural morphine or bupivacaine was given for 42 h postoperatively. Pain intensity (visual analog scale) was low in both groups, but lower (P less than 0.05) in the epidural bupivacaine group. The time to first passage of flatus was 22 +/- 16 h in the epidural bupivacaine group and 56 +/- 22 h in the epidural morphine group (P less than 0.001). The time to first postoperative passage of feces was shorter (P less than 0.05) in the former than in the latter 57 +/- 44 h vs 92 +/- 22 h). The patients of the epidural bupivacaine group started intake of oral fluids earlier (P less than 0.01) and to a greater extent (P less than 0.05) than those in the epidural morphine group. It is concluded that the duration of postoperative ileus after hysterectomy is shorter when epidural bupivacaine is given for postoperative pain relief than when this is achieved by epidural morphine.  相似文献   
43.
小径微孔聚氨酯人工血管的顺应性   总被引:2,自引:0,他引:2  
由激光测微器、压力传感器、A/D卡、微电脑和循环回路等组成的装置测定了小径人工血管的径向顺应性,由微注射器、压力传感器等组成的装置测定了体积顺应性,轴向顺应性由体积顺应性和径向顺应性计算出。体积顺应性,径向顺应性和轴向顺应性都随血管材料弹性的增大、盐/胶比的增加(孔隙率)和浸渍层数(血管壁厚度)的减小而增大。PU血管的外周模量与径向模量分别由径向顺应性。轴向顺应性计算,外周模量与径向模量之比值接近1,即两模量大小与变形方向无关。外周模量与径向模量随血管材料弹性和盐/胶比增加而变小。但管壁厚度对其的影响不大。通过合理选择更具弹性的PU材料(Chro佳,PCU1500次之),最佳盐/胶比例(6:1)以及控制浸渍层数(4~6层),可以制备出顺应性接近天然血管的小径人工血管。  相似文献   
44.
BACKGROUND: Low-dose flutamide-metformin has been developed as a background therapy for non-obese adolescents and young women with hyperinsulinaemic hyperandrogenism, a variant of polycystic ovary syndrome (PCOS). We verified whether the lipolytic efficacy of flutamide-metformin in women with PCOS is enhanced by giving an oral contraceptive (OC) co-therapy that contains drospirenone, instead of gestodene, as progestin. METHODS: An open-labelled study was carried out in which non-obese women with PCOS (n = 29; age approximately 20 years), who had been on a combination of flutamide (62.5 mg/day), metformin (850 mg/day) and ethinylestradiol-gestodene for 8-15 months, were randomized for replacement of the gestodene OC by a drospirenone OC. Assessments of endocrine-metabolic state and body composition (by dual-energy X-ray absorptiometry) were performed at randomization and after 6 months. RESULTS: The switch to drospirenone OC was accompanied by a reduction of total and abdominal fat (mean -0.8 and -0.5 kg) and by an increment of lean body mass (+0.6 kg; all P < 0.01), so that body adiposity was strikingly reduced without changing body weight. CONCLUSION: In non-obese women with PCOS, low-dose flutamide-metformin reduces total and abdominal fat excess more effectively if contraceptive co-therapy contains drospirenone, instead of gestodene, as progestin.  相似文献   
45.
We report a case of the unusual location of a cutaneous bronchogenic cyst on the abdominal wall. The patient was a 9-month-old boy who had presented with a 1.5 cm-sized polypoid mass, present since birth. Pathological examination of the excised mass revealed multiple small cystic structures surrounded by the fibroadipose tissue. The lining epithelium consisted of either pseudostratified ciliated columnar epithelium with goblet cells or a single layer of ciliated or non-ciliated cuboidal to columnar cells. The cystic walls contained a well-developed smooth muscle bundle, mucous glands and hyaline cartilage plate. This lesion was adherent to the peritoneum, but there was no direct communication with the abdominal cavity. Cutaneous bronchogenic cyst located in the abdominal wall has not been described in the English literature. The present case suggests a possible origin from a downward migration, from the sequestered bud of a tracheobronchial tree primordium along the midline of the body surface, during embryonic development.  相似文献   
46.
Children seen in a multispecialty medical clinic for abdominalpain were divided into three groups: 21 with confirmed organicfindings related to the abdominal pain, 14 with confirmed organicfindings unrelated to the pain, and 108 whose physical examinationswere negative (the functional pain group). For children withfunctional abdominal pain (but not for the others) the numberof symptoms of somatization disorder (Briquet's syndrome) wassignificantly related to the chronicity of the child's condition.Children with functional pain and no prior complaint had a meanof 1.95 symptoms; those with complaints of less than 1 year'sduration, 2.21 symptoms; those with complaints of more thana year since age 6, 4.04 symptoms; and those with complaintsfor more than a year with onset prior to age 6 years, 4.55 symptomsfrom the Somatization Disorder list. Findings were interpretedas preliminary evidence for a distinct, chronic, polysymptomatichysterical disorder beginning in childhood.  相似文献   
47.
目的探讨腹部手术病人自控舒芬太尼静脉镇痛的临床效果及安全性。方法选择气管内插管全身麻醉腹部手术患者计80例,ASA分级Ⅰ~Ⅱ级,年龄18~86岁,高中以上文化程度。随机分为两组,每组40例,一组为舒芬太尼镇痛组(S组),术后镇痛药物配方:舒芬太尼2μg/kg+格拉司琼6mg加生理盐水至100ml;另一组为芬太尼镇痛组(F组),术后镇痛药物配方:芬太尼20μg/kg+格拉司琼6mg加生理盐水至100ml。镇痛泵参数均设置为:负荷剂量4ml,背景输注速度1ml/h,自控剂量0.5ml,锁定时间15min。观察S组与F组的镇痛效果及不良反应。结果S组在各个时段静态和动态VAS评分均低于F组(P〈0.05);S组镇静效果较F组评分略高,但两者差异无统计学意义(P〉0.05);S组不良反应发生率少于F组(P〈0.01);两组患者均未见明显的呼吸抑制发生。术后随访两组患者对镇痛效果的总满意度均在90%以上。结论腹部手术病人自控舒芬太尼静脉镇痛,具有良好的镇痛和镇静作用及安全性,且心血管的稳定性好,不良反应低。  相似文献   
48.
Multimodal soma diameter spectra for neurones of the cat retinal ganglion cell layer have been represented by three subpopulations of independent, normal diameter distribution. Recurrent computation according to the technique of Vibert and Caille (1978) has extracted best fit populations for samples from various regions of central and peripheral retina. The model subpopulations from all these regions did not differ significantly in their relative proportions or variance. Significant progressive variation between subpopulations representing different regions of retina were observed only in the mean diameter of the and mode cells. The parameters of the mode population were statistically uniform across the retina. The cat retina thus appears to be more homogeneously organized than has been suggested elsewhere.  相似文献   
49.
目的:探讨腹部良性疾病患者手术前后血清Cortisol、PRL、GH水平的变化,以评价不同阶段的应激情况。方法:Cortisol和PRL采用化学免疫发光法,GH采用放射免疫分析。结果:32例患者Cortisol水平在手术前24h抽血测定结果与对照组比较略有升高,但统计差异无显著性(P〉0.05);麻醉前的血清标本测定结果则升高较为显著,与对照组比较有显著差异(P〈0.05);术后24h的血清标本测定数值升高幅度更为明显,较对照组比较差异极为显著(P〈0.01)。PRL含量在术前24h抽血测定血清浓度也稍有上升,与对照组比较无统计学意义(P〉0.05);上手术台后麻醉前抽取的血清标本测定结果则明显升高,与对照组比较有显著差异(P〈0.05);术后24h的血清标本测定结果PRL水平升高更加明显(P〈0.01)。GH水平在术前24h抽血测定时与上述2项指标的情况基本相同;其余麻醉前和手术后24h的2次血标本测定统计情况亦与上2种指标大致相同(P〈0.05,P〈0.01)。结论:本文患者三项血清指标的变化证实患者存在明显的应激反应;如这种反应过度,则提醒临床应对患者实施必要的处理。  相似文献   
50.
本研究用螺旋CT扫描腹主动脉瘤获得的断层图像合成腹主动脉瘤几何模型,通过设定瘤壁组织生物力学参数和边界条件,使用有限元分析的方法分析腹主动脉瘤瘤壁的应力分布。结果标明,本例腹主动脉瘤应力峰值位于远端分叉部位,瘤体应力峰值位于后壁,均小于瘤壁的承受极限。本研究所得结果对腹主动脉瘤应力模型有助于分析个体化腹主动脉瘤的破裂部位和生长方向,对研究疾病进程提供依据。  相似文献   
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