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71.
目的:了解检验专业学生入学时和毕业前的HBsAg感染率的情况,找出引起检验专业学生HBsAg感染率升高的原因,为制定切实有效的预防措施打下牢固的基础。方法:对该专业学生进行入学时和毕业前采用ELISA法检查HB-sAg。结果:3届学生入学时HBsAg感染率差异无显著性,性别间HBsAg感染率差异无显著性,社区医学专业学生HBsAg感染率入学时与毕业前比较差异无显著性,而检验专业学生HBsAg感染率入学时与毕业前比较差异有显著性。结论:部分检验专业学生没有树立正确的安全范意识,自我保护能力较差,从而造成了自身的感染。  相似文献   
72.
A design technique (Control of Uncertain Systems with Bounded Inputs, Tarbouriech S, Garcia G, (Eds), Lecture Notes in Control and Information Sciences, vol. 227 , Springer: Berlin, 1997; 173–186) recently proposed for stabilization of a linear system with rate‐limited actuators is utilized to design feedback laws that cause the system output to track a desired command signal. This design technique combines two design techniques recently developed for linear systems with position limited actuators, piecewise‐linear LQ control (Automatica, 1994; 30 : 403–416) and low‐and‐high gain feedback (IEEE Trans. Automat. Control, 1996; 41 : 368–378), and hence takes advantage of both design techniques, while avoiding their disadvantages. In the case that only the output is available for feedback, the performance of the state feedback law is preserved by the use of a fast observer. An open‐loop exponentially unstable fighter aircraft is used to demonstrate the effectiveness of the proposed control design method. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
73.
目的:评价自主神经活动在高血压病中的调节作用。方法:观测100例高血压病(Ⅰ组)和54例正常人(Ⅱ组)及高血压病伴心电图改变(ⅠA组)和不伴心电图改变(ⅠB组)心率变异性(以下称HRV)时域参数SDNN、rMSSD、PNN50、Bottom4项指标。结果:Ⅰ组与Ⅱ组差异有显著性(P<0.05);ⅠA组与ⅠB组组差异无显著性(P>0.05)。结论:在高血压病中,交感神经张力增高,副交感神经活动减弱及损伤可能是HRV降低的重要因素。  相似文献   
74.
Steven L. Bressler   《Brain research》1987,409(2):294-301
The major projection pathway of the olfactory bulb is by way of the lateral olfactory tract (LOT) to the olfactory cortex. Oscillatory bursts of extracellular potential appear during inspiration in both bulb and cortex. Based on anatomical and physiological considerations, a model was proposed, consisting of a bulbar transmitter, a conduction line representing axons in the LOT, and a cortical receiver. The model predicted the relation between phase and frequency of bulbar and cortical burst pairs, based on the expectation that the bulb drives the cortex. Experimental phase-frequency plots were computed from bursts of 9 bulbocortical electrode site pairs from each of 10 rabbits. For each site pair, the model predicted the expected range of the joint variation of phase and frequency, using the known distance between the bulbar and cortical sites. The model was highly successful (greater than 95% prediction accuracy) for one quarter of the total number of site pairs examined. The wide range of variation for the rest of the data suggested that higher order interactions are responsible for the phase relation between bulb and cortex. Convergence of input, independence of the cortical generator, cortical feedback to the bulb and synchronization by an outside source are all discussed as possible contributors to this variation.  相似文献   
75.
荷包环扎式结直肠吻合保肛术治疗低位直肠癌*   总被引:1,自引:1,他引:0  
目的 :评价荷包环扎式结直肠吻合保肛术治疗低位直肠癌的价值。方法 :对低位直肠癌采用荷包环扎结直肠吻合保肛术治疗 2 3例 (A组 ) ,采用Miles手术治疗 2 6例 (B组 )。结果 :A组术后 1、3年生存率分别为 10 0 % (2 3/ 2 3) ,95 7% (2 2 / 2 3) ,术后无局部复发病例 ;排便功能优 16例 (6 9 6 % ) ,良 7例 (30 4 % )。B组术后 1、3年生存率分别为 10 0 % (2 6 / 2 6 ) ,96 2 % (2 5 /2 6 ) ,术后局部复发率 3 8% (1/ 2 6 )。两组术后 1、3年生存率 ,局部复发率经统计检验 ,均无显著差异 (P值均 >0 0 5 )。术后并发症 :A组无吻合口瘘及吻合口狭窄发生 ,盆腔感染 1例。B组 :切口感染 1例 ,人工肛门狭窄 1例。结论 :采用螺纹支架管荷包环扎结直肠吻合保肛术治疗低位直肠癌既能达到根治目的 ,又有保留肛门的良好排便功能 ,且并发症少 ,操作简便易行 ,不用特殊器械 ,值得推广应用  相似文献   
76.
目的探讨肥胖患者下腹部手术采用Joel—Cohen切口对预防非感染性切口裂开的临床效果。方法选择切口部位皮下脂肪层厚达4—5cm的妇产科手术患者90例,随机分为观察组44例,采用Joel—Cohen切口;对照组46例,采用下腹正中直切口。观察切口愈合和脂肪液化情况。结果观察组切口甲级愈合率显著高于对照组(P〈0.01);脂肪液化切口裂开率显著低于对照组(P〈0.05)。结论脂肪组织厚达4—5cm以上下腹部手术切口,采用Joel—Cohen切口可以减少脂肪液化,切口愈合显著优于下腹直切口,值得临床推广应用。  相似文献   
77.
For several genetic diseases two biological phenomena have been recognised as important: germline mosaicism; and different new mutation rates in males and females depending on mutation type. Both principles have been investigated separately and their influence on risk estimation in families has been exemplified in the literature. The aim of this paper is to present a general model that includes mosaicism and different new mutation rates. Mosaicism is introduced by defining additional alleles at the disease locus in combination with adapted segregation rules. Taking Duchenne muscular dystrophy as an example, we derive the conditions which have to be fulfilled for a population in mutation selection equilibrium. Our approach describes the model at the population level and not in individual subjects. This has the advantage of being able to use well known algorithms for the calculation of likelihoods in pedigrees, and to include additional diagnostic information such as marker genotypes and carrier deletion test results. We demonstrate the impact of the new model on a typical pedigree. In families where the patient is not available, the distinction between point mutations and deletions is important, since often molecular diagnostic tests for females can only screen for deletions. Negative deletion test results can now be included in the risk calculations.  相似文献   
78.
Serum levels of Epinephrine (E), norepinephrine (NE), heart rate (HR), skin conductance reaction (SCR) and skin conductance level (SCL) were measured in schizophrenic, endogenous depressed and anxiety patients as well as in normal controls. Conditions were rest, noise and a mental arithmetic (MA) task. Schizophrenic and depressed patients had an attenuated HR response to MA. Moreover, Schizophrenic patients also had higher NE base level and the highest NE secretion during noise. Anxiety and depressed patients showed significantly lower phasic electrodermal activity (SCR) throughout the whole trial, exclusively anxiety patients had significantly higher tonic electrodermal activity (SCL). These findings indicate that autonomous reactions discriminate between patient groups and controls as well as between each other.  相似文献   
79.
目的探讨第一产程胎心监护异常的相关因素,提示处理措施。方法2004年1月1日。12月31日对我院226例第一产程胎心监护异常的相关因素进行回顾性分析。结果第一产程胎心监护异常为综合因素所致,胎儿高危因素为91.59%,母体高危因素为65.49%,产程处理因素为42.92%。结论第一产程胎心监护异常主要与胎儿因素、母体因素有关,提高产前检查质量、加强产程监护、正确选择分娩方式极为重要。  相似文献   
80.
目的:为了解女职工患妇女病现状,充分认识普查普治必要性。方法:对玉溪市部分女职工进行常规妇科检查、白带多项快染、宫颈荧光筛查、乳腺红外线扫描。结果:女职工患病率74.54%,阴道炎患病率18.67%,宫颈糜烂患病率21,04%,子宫肌瘤占受检人数10.79%,慢性输卵管炎占9.60%,卵巢囊肿占4.3%,乳腺小叶增生患病率为26.86%,乳腺纤维瘤占0.43%,IF荧光宫颈癌筛查3-4分占8.33%。结论:女职工患病率高,提高宣传力度,定期开展妇女病普查普治尤为必要。  相似文献   
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