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81.
82.
开放实验室的初步探讨 总被引:5,自引:0,他引:5
开放实验室是近年来高校实验教学改革的新举措,本文从管理的角度阐述了开放实验室在实验教学改革中对培养学生的实践能力、创新意识、个性化发展等方面发挥的重要作用。从实验时间、实验内容以及仪器设备共享等方面进行了重点讨论。 相似文献
83.
颈椎骨折常合并有不同程度的脊髓神经功能损伤及颈椎不稳定,对颈脊髓损伤治疗的目的是恢复颈椎的生理解剖关系,重建脊柱的稳定性,防止神经组织的继发性损伤,促进神经功能的恢复,早期无痛情况下的功能康复。2000年8月至2004年8月应用前路槽式减压自体长方体髂骨植骨钛合金钢板固定治疗下颈椎骨折46例,效果满意,总结如下。1临床资料本组46例,均为男性,年龄21~62岁,平均47·3岁。受伤原因:交通事故伤26例,坠落伤20例。骨折部位:C33例,C412例,C516例,C610例,C4、C5同时骨折5例。骨折类型:垂直压缩性骨折4例,屈曲型压缩性骨折23例,过伸型压缩… 相似文献
84.
人类免疫缺陷病毒(human immunedeficiency virus,HIV)感染后病毒携带者在发病后出现神经系统受累者占39%~65%,而尸检发现中枢神经系统(central nervous systern,CNS)受累率高达73%~90%,AIDS累及CNS的影像检查方法首选MRI,其对病变检出率高,增强MRI可进一步显示病变,发现血脑屏障破坏。本文总结9例经实验室血清学检查HIV阳性患者颅内病变的MRI表现并结合临床进行分析。1材料与方法本组9例中,男6例,女3例,年龄20~49岁,平均36岁。临床表现9例患者有不同程度头痛、头晕,意识及肢体活动障碍,3例有发热,3例有吸毒史。实验室检查:血清H… 相似文献
85.
目的为探讨结直肠癌术后复发的原因、诊断和术后复发的治疗效果。方法笔者回顾性分析10年间收治的60例结直肠癌术后复发患者的临床资料。结果手术后2年内复发40例(66.7%)。60例中吻合口处复发15例,腹腔、盆腔内复发20例,会阴部复发10例,肝脏转移8例,腹壁切口复发7例。全组患者均再次行手术治疗,其中根治性切除38例,姑息性切除22例。再手术后的1,3,5年生存率根治性切除分别为93.6%,48.8%,36.3%;姑息性切除为54.5%,0,0。结论重视术中无瘤技术、切除足够的肠管、彻底清除淋巴结及其所在的肠系膜、消灭微小转移灶是预防结直肠癌术后复发的主要措施。对复发患者应根据复发部位、病期早晚选择以手术为主的综合治疗方案。 相似文献
86.
Mário Martins Oliveira Nogueira da Silva Ana Teresa Timóteo Joana Feliciano Lídia de Sousa Sofia Santos Fernando Marques Rui Ferreira 《Revista portuguesa de cardiologia》2007,26(7-8):691-702
Atrial electrical remodeling plays a part in recurrence of atrial fibrillation (AF). It has been related to an increase in heterogeneity of atrial refractoriness that facilitates the occurrence of multiple reentry wavelets and vulnerability to AF. AIM: To examine the relationship between dispersion of atrial refractoriness (Disp_A) and vulnerability to AF induction (A_Vuln) in patients with clinical paroxysmal AF (PAF). METHODS: Thirty-six patients (22 male; age 55+/-13 years) with > or =1 year of history of PAF (no underlying structural heart disease--n=20, systemic hypertension--n=14, mitral valve prolapse--n=1, surgically corrected pulmonary stenosis--n=1), underwent electrophysiological study (EPS) while off medication. The atrial effective refractory period (AERP) was assessed at five different sites--high (HRA) and low (LRA) lateral right atrium, high interatrial septum (IAS), proximal (pCS) and distal (dCS) coronary sinus--during a cycle length of 600 ms. AERP was taken as the longest S1-S2 interval that failed to initiate a propagation response. Disp_A was calculated as the difference between the longest and shortest AERP. A_Vuln was defined as the ability to induce AF with 1-2 extrastimuli or with incremental atrial pacing (600-300 ms) from the HRA or dCS. The EPS included analysis of focal electrical activity based on the presence of supraventricular ectopic beats (spontaneous or with provocative maneuvers). The patients were divided into group A--AF inducible (n=25) and group B--AF not inducible (n=11). Disp_A was analyzed to determine any association with A_Vuln. Disp_A and A_Vuln were also examined in those patients with documented repetitive focal activity. Logistic regression was used to determine any association of the following variables with A_Vuln: age, systemic hypertension, left ventricular hypertrophy, left atrial size, left ventricular function, duration of PAF, documented atrial flutter/tachycardia and Disp_A. RESULTS: There were no significant differences between the groups with regard to clinical characteristics and echocardiographic data. AF was inducible in 71% of the patients and noninducible in 29%. Group A had greater Disp_A compared to group B (105+/-78 ms vs. 49+/-20 ms; p=0.01). Disp_A was >40 ms in 50% of the patients without A_Vuln and in 91% of those with A_Vuln (p=0.05). Focal activity was demonstrated in 14 cases (39%), 57% of them with A_Vuln. Disp_A was 56+/-23 ms in this group and 92+/-78 ms in the others (p=0.07). Using logistic regression, the only predictor of A_Vuln was Disp_A (p=0.05). CONCLUSION: In patients with paroxysmal AF, Disp_A is a major determinant of A_Vuln. Nevertheless, the degree of nonuniformity of AERP appears to be less important as an electrophysiological substrate for AF due to focal activation. 相似文献
87.
目的:探讨儿童在X线体检中减少照射剂量的方法。方法:应用东芝500mA遥控X线机、FJ-427型热释光剂量仪等设备,对100名3~5岁儿童体检时,随机分成两个对照组、每组50名,分别接受胸透或平片检查,对检查测得数据均进行统计学处理。结果:胸透时胸部接受的照射剂量是平片的22倍多,其它部位接受的X线散射剂量平均值之比亦在20~30倍之间。结论:在儿童X线体检中应采用常规胸片替代胸透,可以有效地降低其辐射危害。 相似文献
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90.
Jorge Polónia Jo?o Maldonado Rui Ramos Susana Bertoquini Mary Duro Cristina Almeida Jo?o Ferreira Loide Barbosa José Alberto Silva Luís Martins 《Revista portuguesa de cardiologia》2006,25(9):801-817
BACKGROUND: Portugal has one of the highest mortality rates from stroke, a high prevalence of hypertension and probably a high salt intake level. AIM: To evaluate Portuguese salt intake levels and their relationship to blood pressure and arterial stiffness in a sample of four different adult populations living in northern Portugal. METHODS: A cross-sectional study evaluating 24-hour urinary excretion of sodium (24 h UNa+), potassium and creatinine, blood pressure (BP), and pulse wave velocity (PWV) as an index of aortic stiffness in adult populations of sustained hypertensives (HT), relatives of patients with previous stroke (Fam), university students (US) and factory workers (FW), in the context of their usual dietary habits. RESULTS: We evaluated a total of 426 subjects, mean age 50 +/- 22 years, 56% female, BMI 27.9+/-5.1, BP 159/92 mmHg, PWV 10.4+/-2.2 m/s, who showed mean 24h UNa+ of 202 +/- 64 mmol/d, corresponding to a daily salt intake of 12.3 g (ranging from 5.2 to 24.8). The four groups were: HT: n = 245, 49 +/- 18 years, 92% of those selected, 69% treated, BP 163/94 mmHg, PWV 11.9 m/s, 24 h UNa+ 212 mmol/d, i.e. 12.4 g/d of salt); Fam: n = 38, 64 +/- 20 years, 57 % of those selected, BP 144/88 mmHg, PWV 10.5 m/s, 24 h UNa+ 194 mmol/d, i.e. 11.1 g/d of salt; US: n = 82, 22 +/- 3 years, 57% of those selected, BP 124/77 mmHg, PWV 8.7 m/s, 24h UNa+ 199 mmol/d, i.e. 11.3 g/d of salt; FW: n = 61, 39 9 years, 47% of those selected, BP 129/79 mmHg, PWV 9.5 m/s, 24 h UNa+ 221 mmol/d, i.e. 12.9 g/d of salt. The ratio of urinary sodium/potassium excretion (1.9 (0.4) was significantly higher in HT than the other three groups. In the 426 subjects, 24h UNa+ correlated significantly (p < 0.01) with systolic BP (r = 0.209) and with PWV (r=0.256) after adjustment for age and BP. Multivariate analysis showed that BP, age and 24h UNa+ correlated independently with PWV taken as a dependent variable. CONCLUSIONS: Four different Portuguese populations showed similarly high mean daily salt intake levels, almost double those recommended by the WHO. Overall, high urinary sodium excretion correlated consistently with high BP levels and appeared to be an independent determining factor of arterial stiffness. These findings suggest that Portugal in general has a high salt intake diet, and urgent measures are required to restrict salt consumption in order to prevent and treat hypertensive disease and to reduce overall cardiovascular risk and events. 相似文献