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51.
基于临床流程功能需求的生理监测仪配置评估   总被引:1,自引:0,他引:1  
病人生理监测仪是临床医学的主要仪器之一,由于所涉及的技术流程定位不同,功能需求也就不同,其功能配置也应有所不同。本文从分解分析生理监测仪相关应用领域的技术定位功能需求出发,讨论卫生技术装备管理的功能配置评估。  相似文献   
52.
本文应用XD—Ⅰ型微电脑程序刺激器检查26例患者,在窦房结功能检查中测定了窦房结恢复时间、窦房传导时间及固有心率;在房室传导功能的估计中测定了文氏点,2∶1阻滞点及房室结的有效不应期;在室上性心动过速中测定了旁路不应期,房室结双通道,折返区及折返性心动过速区;还进行了心脏负荷试验及右束支不应期等方面的测定。并就其方法,判断标准及临床意义等分别作了讨论。  相似文献   
53.
Summary. Heart rate responses to stepwise and periodic changes in lung volume were studied in seven young healthy males. Stepwise inspiration and expiration both resulted in an increase in heart rate followed by a rapid decrease in heart rate. The fastest heart rate was reached in 1·6 ± 0·5 s and in 3·6 ± 1·4 s in response to inspiration and expiration, respectively (P < 0·01). The slowest heart rate was reached in 4·8± 1·0 s and in 7·6± 1·9 s in response to inspiration and expiration, respectively (P < 0·01). Following this biphasic change the heart rate returned to a steady level. The difference between the fastest and the slowest heart rates was significantly larger in response to inspiration (21·7 ± 7·3 beats per minute) than in response to expiration (12·0±7·3 beats per minute; P < 0·01). Periodic changes in lung volume were performed with frequencies from 3·0 to 12·0 respirations per minute (r.p.m.). The changes in heart rate showed a constant amplitude in the frequency range below 5·5 r.p.m. Maximal heart rate changes were found at frequencies of 5·5 to 7·0 r.p.m. Changes in heart rate decreased in a linear manner on a log-log scale in the frequency range above 7·0 r.p.m. The relation between frequency and changes in heart rate is explained by interference between the transient changes in heart rate induced both by inspiration and by expiration. It is concluded that if heart rate changes in response to periodic changes in lung volume are to be used as a measure of vagal function a number of factors have to be taken into consideration and to simplify the analysis of heart rate responses to breathing we recommend, instead, the use of the transient changes in heart rate induced by stepwise changes in lung volume.  相似文献   
54.
55.
目的探讨术中应用前列腺素E1(prostaglandin E1,PGE1)对大鼠肝移植肾功能的保护作用。方法大鼠原位肝移植术中经颈内静脉灌注PGE1为治疗组,生理盐水和空白为对照组,观察术后1周存活率、1h的尿量,测定血浆肌酐、尿素氮和肾组织中丙二醛(malondjaldehyde,MDA)、谷胱甘肽(glutathione,GSH)含量,肾组织病理检查。结果PGE1治疗组术后1h尿量较对照组明显增加,肌酐和尿素氮水平均较对照组降低,PGE1治疗组肾组织中GSH含量显著高于两对照组,MDA含量低于两对照组。病理检查PGE1治疗组肾脏组织形态学损伤明显减轻。结论术中应用PGE1能显著改善大鼠肝移植后的肾功能,其机制可能与对抗氧自由基损伤作用有关。  相似文献   
56.
目的 探讨自制苏芪合剂对Ⅲ~Ⅳ级IgA肾病患者的疗效及患者T细胞功能的改善.方法 28例Ⅲ~Ⅳ级IgA肾病患者随机分为两组,对照组:醋酸泼尼松-日1mg,kg,隔日晨起顿服,盐酸苯那普利-日10mg;治疗组:在上述用药的基础上加用自制苏芪合剂.8周后,观察患者缓解率、T细胞功能及不良反应.结果 治疗组患者在缓解率、T细胞功能改善等方面优于对照组,且因糖皮质激素的使用而出现的不良反应少于对照组.结论 苏芪合剂联合治疗Ⅲ~Ⅳ级IgA肾病疗效显著并能有效改善T细胞功能.  相似文献   
57.
OBJECTIVE: In the present study, we evaluated the anti-inflammatory activity of Poria cocos (PoCo) on experimentally induced irritant contact dermatitis (ICD) in a repeated sodium lauryl sulphate (SLS) irritation model. METHODS: The anti-irritative effect of PoCo was evaluated with a visual score and quantified by non-invasive bioengineering methods, namely chromametry and transepidermal water loss. Three concentrations of PoCo in base cream DAC (amphiphilic emollient; German pharmacopoeia) were tested in a 4-day repetitive irritation test using SLS. RESULTS: A statistically significant anti-inflammatory activity was observed for PoCo by all three methods when applied in parallel to the induction period of ICD. Application of PoCo after induction of ICD once a day for 5 days, starting just at the end of 4 days, was without any effect. CONCLUSION: An anti-inflammatory efficacy of PoCo on the elicitation phase of the ICD induced by repeated SLS test could be observed and quantified by three independent, non-invasive biophysical assessment parameters. This effect can be explained by its influence on pro-inflammatory enzymes, namely phospholipase A2.  相似文献   
58.
A total of 114 patients with various sympathetic disorders underwent endoscopic sympathetic block over different thoracic ganglions by the clipping method. The advantages of this method include the recognition of the clipped level, changeability, and reversibility. However, 4.4% of patients were unilaterally clipped at the wrong level.  相似文献   
59.
Focal full-thickness cartilage lesions of the human medial femoral condyle (MFC) can cause pain and functional impairment. Affected middle-aged patients respond unpredictably to existing treatments and knee arthroplasty may be required, prompting risk of revision. This study assesses the safety of, and biological and functional response to, a metallic resurfacing implant which may delay or obviate the need for traditional arthroplasty. The anatomic contour of the surgically exposed MFC of six adult goats was digitally mapped and an 11 mm diameter full-thickness osteochondral defect was created. An anchor-based Co-Cr resurfacing implant, matching the mapped articular contour, was implanted. Each goat's contralateral unoperated femorotibial joint was used as a control. Postoperative outcome was assessed by lameness examination, radiography, arthroscopy, synoviocentesis, necropsy, and histology up to 26 (n = 3) or 52 (n = 3) weeks. By postoperative week (POW) 4, goats demonstrated normal range of motion, no joint effusion, and only mild lameness in the operated limb. By POW 26 the animals were sound with only occasional very mild lameness. Arthroscopy at POW 14 revealed moderate synovial inflammation and a chondral membrane extending centrally across the implant surface. Radiographs at POWs 14 to 52 implied implant stability in the operated joints, as well as subchondral bone remodeling and mild exostosis formation in the operated and contralateral unoperated joints of some goats. By POW 26, histology revealed new trabecular bone abutting the implant. At POWs 26 and 52 MFC cartilage was metachromatic and intact in the operated and unoperated femorotibial joints. Proximal tibiae of some operated and unoperated limbs demonstrated limited subchondral bone remodeling and foci of articular cartilage fibrillation and thinning. The chondral membrane crossing the prosthesis possessed a metachromatic matrix containing singular and clustered chondrocytes. Our data imply the safety, biocompatibility, and functionality of the implant. Focal articular damage was documented in the operated joints at POWs 26 and 52, but lesions were much reduced over those previously reported in untreated defects. Expanded animal or preclinical human studies are justified.  相似文献   
60.
Previously reported attenuation of skin postural vasoconstriction in women during the luteal menstrual cycle phase may be due to a progesterone-mediated decrease in myogenic or veno-arteriolar (VAR) mechanisms. Skin perfusion was measured in the shin and foot dorsum by Laser Doppler Fluxometry during leg dependency that increased vascular transmural pressure below (myogenic constriction only) and above (myogenic and VAR) the 25 mmHg threshold for activation of the VAR, and during venous distension to activate the VAR alone (cuff inflation to 50 mmHg). In six young women with normal menstrual cycles, vasoconstrictor responses to all interventions did not differ between days 7–13 (follicular) and 18–23 (luteal) of the normal menstrual cycle when progesterone levels were low and at their peak respectively. In eight women taking combined oral contraceptives (OC) and tested during pill consumption days, reductions in foot skin perfusion were smaller (P = 0.05) than in the luteal phase of the normal cycle for leg dependency below (−36.9 ± 5.2% OC vs. −52.5 ± 7.8% luteal, mean ± S.E.M.) and above (−43.7 ± 3.4% OC vs. −55.1 ± 4.8% luteal) the VAR threshold, and for venous distension (−53.1 ± 2.6% OC vs. 66.4 ± 5.5% luteal). In women with normal menstrual cycles, impaired postural vasoconstriction may be confined to those who experience pre-menstrual symptoms rather than a direct effect of endogenous hormones. Reduced vasoconstriction in the dependent foot during OC use is consistent with the known vasodilator action of exogenous hormones and its long-term effects  相似文献   
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