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21.
The comparison of trends in perinatal mortality in small areas   总被引:1,自引:0,他引:1  
Year to year changes in perinatal mortality rates for small populations are difficult to interpret. Because local rates are based on small numbers of events, they are subject to apparently large fluctuations. A technique for analysing trends in mortality, for detecting changes in trends and comparing variations in trends between areas is described. It is illustrated by an analysis of perinatal mortality rates for Area Health Authorities in the West Midlands Region of England from 1974-1981, but the same techniques could be used to analyse trends at other times and in other places.  相似文献   
22.
Turf wars over medical imaging have become ubiquitous. At many centers, radiologists already have lost access to important technologies and their applications. A combination of decreasing revenues in other specialties and a growing attachment to imaging further threatens radiologists’ practices in the future. This is the first of an extended series of articles that will address the phenomenon of self-referral—its motivations, extent, and the threats it poses to radiologists. Each article will focus on a specific aspect and provide advice on how radiologists can deal with self-referral in their locales.  相似文献   
23.
Abstract: This paper dicusses the use of esophageal dilatation with a Rigiflex TTS balloon. This method was used 45 times on 11 patients affected by anastomotic or a severe grade peptic esophageal stenosis. Fluoroscopic guidance was used in 36 procedures (80%) without effecting the mean duration of the treatment (12 minutes). The results were considered satisfactory when these goals had been achieved: a) dilatation of the stenosis over 15 mm; b) a dysphagia free-time of more than 6 months. A satisfactory result was achieved in 10 patients (90.9%), without deaths and major complications. 5 patients received 1 dilatation and the other 5 needed, 3-3-4-7–11 procedures respectively to obtain a satisfactory result. On these basis we consider that its great efficacy, security and tolerability depend on the following characteristics of the Rigiflex TTS balloon: 1) “radial” dilatation; 2) the possibility of introducing the balloon through the operative channel of the fiberscope; 3) direct visualization of the stenosis during dilatation. The following disadvantages with this method are: the absence of a tactile sensation of dilatation and the elevated cost of the instrument. We conclude that the Rigiflex TTS balloon is an important alternative to guide-wire techniques, especially for the treatment of severe esophageal strictures.  相似文献   
24.
目的:探讨妊娠肝内胆汁淤积症(ICP)患者外周静脉血清、新生儿脐静脉血清中一氧化氮(NO)、内皮素(ET)、丙二醛(MDA)和超氧化物歧化酶(SOD)含量的变化及在ICP发病中的作用。方法:以ICP组28例为研究组,测定其外周静脉血清及新生儿脐静脉血清中的NO、ET、MDA和SOD,以年龄相近的24例正常孕妇作为对照组。结果:ICP患者的MDA和ET含量较正常晚期妊娠显著增高(P<0.01),ICP患者的NO和SOD含量与对照组相比无显著性差异(P>0.05)。母血清中NO、ET、MDA含量均较新生儿脐静脉血清中的含量高,差异有显著性(P<0.01)。结论:妊娠期体内氧化和抗氧化失衡及ET水平的增高可能与ICP的发生、发展有关。  相似文献   
25.
Reduction of bacterial adherence to catheter surface with heparin   总被引:1,自引:0,他引:1  
Despite many advances in catheter design and use, the most common cause of hospital-acquired infections is catheterization of the urinary tract. In the present investigation the adherence of bacteria to catheters coated with heparin was studied. Since heparin itself does not coat the plastic catheter surface, a complex of heparin with tridodecylmethylammonium chloride (TDMAC) was used which results in hydrophobic association of hydrocarbon chains of the TDMAC with the catheter leaving the quaternary ammonium moiety of TDMAC exposed to the surface forming ionic bonds with the highly anionic sulfate groups of heparin. Coating latex catheter material with TDMAC without heparin resulted in 3.6-fold higher adherence whereas coating with the TDMAC-heparin complex reduced adherence to less than 10% of control untreated latex. TDMAC-heparin also significantly reduced bacterial adherence to teflon coated latex (Bardex) and vinyl catheter material. Less than 30% of the original heparin was removed after wash periods of up to one week. These results indicate that TDMAC-heparin coating of urethral catheters reduces bacterial adherence and thereby may delay the acquisition of catheter associated urinary tract infection.  相似文献   
26.
Electromyographic (EMG) recordings were obtained by concentric needle electrodes from the bulbocavernosus (BC) and ischiocavernosus (IC) muscles in 7 human volunteers during excitement to erection and subsequent ejaculation. Simultaneous registration of the time course and volume of each expressed spurt of semen was obtained using an aluminium pan suspended in front of the subject's penis on a force transducer the output of which was charted with the EMG activity. The BC and IC muscles showed no EMG activity during erection and detumescence cycles induced by visual sex stimulation. In 5 of 7 subjects, the first EMG burst of the BC in ejaculations induced by masturbation was not correlated with an expelled spurt of semen as were subsequent bursts. However, only 26 to 60% of the total number of EMG bursts were accompanied by expulsion of a spurt of semen. There thus appears to be a large safety factor in the striated muscle expulsive mechanism. Oral phenoxybenzamine treatment in 2 subjects did not significantly affect either the number of EMG bursts of the BC or the subjective pleasure of the orgasm but did significantly reduce the volume of semen expelled. Semen volume does not appear to be a unique determinant of the pleasure felt or the trigger for ejaculation.  相似文献   
27.
Studies were done to compare the acute effects of streptozotocin-induced diabetes and sucrose consumption on micturition, bladder mass and contractile responses of bladder strips to field stimulation and contractile agonists. Micturition changes occurred gradually in diabetic rats, reached maximal values within 7 to 14 days, and were accompanied by significant increases in bladder mass after 7 days. Bladder strips from diabetics responded to field stimulation, carbachol and KCl with significantly greater contractions than did those from controls within 7 days. Sucrose-drinking rats had maximal increases in fluid consumption and micturition frequency on the first night after starting treatment. Increases in micturition volumes were slower to develop than in diabetics. Bladder mass was significantly increased 30 and 60 days after starting sucrose treatment. Bladder strips from sucrose-drinking rats responded to field stimulation and carbachol with significantly greater contractions than did those from controls only after 60 days. Monitoring of drinking and micturition patterns established that diabetic rats drink and urinate during both the dark and light cycles. In contrast, control and sucrose-drinking rats drink and urinate principally at night. The results demonstrate that differences in bladder function between diabetic and sucrose drinking rats are apparent during the first month after treatment begins. The data suggest that the effects of diabetes and sucrose consumption on contractile bladder function are related to the diuresis-induced increases in bladder mass.  相似文献   
28.
OBJECTIVE: The authors describe their experience with left ventricular assist-device (LVAD) recipients undergoing noncardiac surgery and delineate surgical, anesthetic, and logistic factors important in the successful intraoperative management of these patients. SUMMARY BACKGROUND DATA: Left ventricular assist-devices have become part of the armamentarium in the treatment of end-stage heart failure. As the numbers of patients chronically supported with long-term implantable devices grows, general surgical problems that are commonly seen in other hospitalized patients are becoming manifest. Of particular interest is the intraoperative management of patients undergoing elective noncardiac surgical procedures. METHODS: The anesthesia records and clinical charts were reviewed for eight ventricular assist-device recipients undergoing general surgical procedures between August 1, 1990 and August 31, 1994. RESULTS: A total of 12 procedures were performed in 6 men and 2 women averaging 52.7 years of age. Mean time elapsed from device implantation to operation was 68 +/- 35 days. Conventional inhalational and intravenous anesthetic techniques were well tolerated in these patients undergoing diverse surgical procedures. No perioperative mortality was observed. Five of eight patients went on to successful cardiac transplantation. CONCLUSIONS: Hemodynamic recovery after LVAD insertion has defined a new group of patients who develop noncardiac surgical problems often seen in other critically ill patients. Recognition of the unique potential problems that the LVAD recipient may encounter in the perioperative period--in particular patient positioning, device limitations, and fluid and inotropic management--will ensure an optimal surgical outcome for LVAD recipients undergoing noncardiac surgery.  相似文献   
29.
MR using a susceptibility-weighted sequence and dynamic contrast enhancement with gadolinium demonstrated relative hyperperfusion of the right temporoparietal cortex in a patient in focal status epilepticus. A single-photon emission CT (SPECT) scan also demonstrated hyperperfusion of the right temporoparietal cortex. Perfusion MR, SPECT, and electroencephalogram normalized when the seizures ended.  相似文献   
30.
Despite growth in the field of gerontological research over the past 50 years, no consensus has emerged on either the definition of gerontology or on its scope and boundaries. This confusion is rooted historically in developments involving the origins and adoption of the term. These include the divergent agendas and world views of particular disciplines and gerontological institutions, as well as conflicts over both ideology and turf among major gerontologists. Speculation is offered on the potential, as well as the costs, of developing consensus-in the future.  相似文献   
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