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We have investigated contamination of extradural catheters during normal handling with starch powdered gloves. In the laboratory, extradural catheters were handled in sterile fields with both powdered and non-powdered gloves, simulating preparation for patient insertion. The catheters together with glove samples were then examined using a Zeiss 940 scanning electron microscope. Microscopy of samples revealed starch contamination of the catheters handled with powdered gloves, especially in the side hole areas. We conclude that extradural catheters may be contaminated easily by starch powder from surgical gloves. This powder may then be deposited into the extradural space. The effect of starch in the extradural space is not known but starch is known to cause inflammatory and granulomatous reactions in other parts of the body as well as being directly allergenic. Powder contamination of catheters may be avoided easily by the use of powder-free gloves and we feel that these should be used whenever possible.   相似文献   
64.
Fatal haemopericardium in a 27 year old pregnant woman was caused by rupture of a dissecting aneurysm of the pulmonary artery. She had an uncorrected patent ductus arteriosus and severe pulmonary hypertension. The wall of the pulmonary artery showed atherosclerosis and cystic medionecrosis.  相似文献   
65.
Compared with both industrialized countries and other less developed parts of the world, most of sub-Saharan Africa suffers inordinately from sexually transmitted diseases (STDs). It has high prevalence rates of traditional STDs, such as gonorrhea and syphilis, and if accurate seroprevalence surveys were to be done, it would probably prove to have the highest HIV seropositive incidence in the world. Unlike the pattern in the West, AIDS is primarily a heterosexually transmitted disease in Africa. This appears to be largely because of the prevalence of other untreated or improperly treated STDs. Therefore to lower the incidence of STDs would be to curtail the spread of HIV infection. The problem becomes how exactly to accomplish this. Most STD cases are never even presented at biomedical health facilities; they are presented to traditional healers. Both healers and their patients seem to believe that traditional STD cures are more effective than 'modern' cures, although the former are probably biomedically ineffective. While there is scant ethnomedical literature on STDs in Africa, the present paper presents Swaziland findings and related evidence from other African societies that the ultimate cause of several common STDs is believed to be the violation of norms governing sexual behavior, requiring traditional rather than biomedical treatment. Traditional healers therefore need to be a central part of any scheme to lower the incidence of STDs.  相似文献   
66.
Introduction: apoptosis in the immune system.   总被引:5,自引:0,他引:5  
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67.
F E Liss  S M Green 《Hand Clinics》1992,8(4):755-768
Although capsular injuries of the PIP joints are common, their management is frequently complicated. Successful treatment must begin with a detailed history because reviewing the mechanism of injury may provide information relevant to the pathomechanics of the capsular disruption and facilitate making an accurate diagnosis. Grades I and II volar plate and collateral ligament sprains represent the vast majority of PIP joint injuries. They are best treated with a short period of dorsal splinting followed by supervised mobilization. Although splinting is also applicable for grade II sprains associated with instability and most grade III sprains, the initial period of immobilization should be longer. The prognosis for recovery is generally good, although some residual tenderness or joint stiffness are common complications. Dorsal capsular injuries, if unrecognized, result in deformity rather than instability. The majority of these injuries can also be treated by closed means, but they require more prolonged immobilization and more commonly result in reduced mobility than volar plate and collateral ligament injuries. Capsular injuries that are compound, irreducible, or associated with a large intraarticular fracture can result in serious problems. Frequently, these injuries require primary surgical treatment, particularly in the case of the irreducible dislocation, which always requires surgery. An exception to the generally poor prognosis of these injuries is the irreducible volar dislocation because the central tendon remains intact permitting early postoperative joint mobilization. A chronic dislocation or late instability are fortunately not common sequela of capsular injuries; however, when they do occur, surgery is required.  相似文献   
68.
Total and subcellular (cytosol and nuclear) concentrations of estrone (E1), estradiol (E2), and androstenedione were determined in non-malignant (n = 61) and malignant (n = 65) human breast tissues obtained from post-menopausal women. The 17 beta-hydroxysteroid dehydrogenase (17 beta-OH-SDH) activity was determined in 800g supernatant fraction. Total estrogens, E1 and E2 levels and 17 beta-OH-SDH activity were significantly (p less than 0.005, 0.0005, 0.001, respectively) higher in malignant than in non-malignant breast tissues. We failed to observe significant changes in subcellular steroid concentrations or enzyme activity associated with patients' obesity or tumor estrogen receptor status. When the steroid levels were analyzed in relation to clinical staging of the disease, nuclear contents of estradiol were significantly higher (p less than 0.005) in Stage-IV patients than in those with less advanced disease (Stages I to III). 17 beta-OH-SDH activity was significantly (p less than 0.001) lower in patients with advanced disease than in those with relatively less advanced (Stages I to III) disease and was positively correlated with tissue concentration of androstenedione. Our present data indicate that differential intracellular metabolism of steroid hormones may have some influence on availability of estradiol at nuclear sites. In postmenopausal women, local interconversion of estrogens may provide sufficient estrogenic stimulus to enhance the growth and progression of breast tumors.  相似文献   
69.
A. Green 《Diabetologia》1987,30(3):188-192
Summary To determine whether adenosine is involved in long-term regulation of glucose transport in adipose tissue, we have investigated effects of administration of an adenosine receptor antagonist (theophylline) on adipocyte glucose transport. Rats were injected with theophylline (30 mg/kg, dissolved in 0.9% NaCl) daily for 7 days. Controls were injected with saline. The rats were then killed, and epididymal adipocytes were isolated. Insulin-stimulated glucose transport rates were decreased by about 25%–30% in the cells from theophylline-treated rats at all insulin concentrations tested. The half-maximally effective concentration of insulin was not altered (6.5±0.5 and 6.7±0.5 mU/l in control and treated cells respectively), suggesting a post-insulin binding defect. This was confirmed by the finding that 125I-insulin binding to the cells was not altered. Adenosine receptor number and affinity (measured on detergent-solubilized adipocyte extracts using 125I-hydroxyphenylisopropyl adenosine) was also not changed by theophylline treatment. We conclude that theophylline administration causes decreased glucose transport rates in rat adipocytes at a post-insulin binding level. Thus, chronic adenosine receptor blockade impairs adipocyte glucose transport, suggesting that adenosine is involved in long-term regulation of glucose metabolism in adipose tissue.  相似文献   
70.
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