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941.
942.
Certain groups of patients requiring enteral nutritional support are at increased risk of regurgitation and pulmonary aspiration of feed. Positioning of enteral feeding tubes distal to the pylorus has been advocated as a method of reducing such complications. Various techniques have been suggested to achieve postpyloric siting. Reports have indicated that lengthening the tube or altering the distal end tip configuration, by varying the tip profile or by the addition of a weight, may facilitate spontaneous transpyloric passage of the tube. This prospective controlled clinical study using three new polyurethane tubes demonstrates that the frequency of spontaneous transpyloric passage of the tube is not affected by tip profile or by the addition of a weight. Indeed, with all three tube designs only about one-third had passed spontaneously through the pylorus at 24 hr. Once through the pylorus the unweighted tube stayed in position significantly longer than the weighted tubes (p less than 0.005). We suggest that in those patients requiring post-pyloric feeding, endoscopic or fluoroscopic techniques should be used to position the tubes at the time of insertion, and that an unweighted tube should be used to prolong tube usage.  相似文献   
943.
944.
A cross-sectional, longitudinal study was undertaken on a group of acute non-A, non-B hepatitis patients, as well as on a control group of hepatitis B patients, in order to assess both the prevalence of the most important factors favoring infection, and the relevance of these factors in promoting evolution towards chronic liver disease. Exposures to unknown risk factors were present in 47.4% of acute non-A, non-B infections, followed by blood transfusions (17.9%), sporadic exposures (17.9%) and drug addiction (16.6%). Unknown as well as sporadic exposures showed a greater prevalence in control population if compared to non-A, non-B cases, while drug addiction was equally represented in the two groups, and blood transfusion nearly absent from control group. The risk of evolution to chronic liver disease was about 13 times greater in non-A, non-B group than in controls, with the greatest risk for drug addicts and the lowest for patients with unknown exposures. Among patients with known exposures, the lowest risk of chronic hepatitis was observed in post-transfusion and in sporadic cases, while the greatest was observed in drug addicts.Corresponding author.  相似文献   
945.
946.
947.
The number and complexity of available tests and therapies is expanding and financial resources are shrinking. Clinicians must now consider how to give the best care while limiting health expenses. Decision analysis is a tool used to guide clinicians in the practice of medicine, and to supplement and enhance intuitive decision making based on clinical experience.  相似文献   
948.
The pilot study for a sentinel health events surveillance system for deaths among persons under age 45 with diabetes was conducted in six states in 1984 and 1985. Two hundred and thirty-three events were identified. Information from death certificates, physicians, and families revealed that 22% died from acute complications of diabetes and 53% from chronic complications. Blood pressure measurement and urinalysis testing had been performed in the last year for almost all of the decedents, but other preventive practices were reported less frequently. Hypertension was present in 57% and of those, was not controlled in 73%. Forty-four percent were cigarette smokers at the time of death. Agreement between physicians and families was generally higher for clinical conditions than for care practices. This surveillance system appears to yield information about the health care of persons with diabetes not readily available from other sources, although modifications may be necessary before implementation.  相似文献   
949.
950.
The composition of the clientele from an ophthalmological practitioner's office is described with special reference to the occurrence of glaucoma and disc haemorrhages (h in singular; hh in plural). This study could not be planned as an epidemiological survey and gives no clue to sensitivity or specificity of hh in glaucoma. During a period of about 10 years ending with 1986 there were 731 patients with h and/or glaucoma. When detected, 185 patients had h but no glaucoma, 33 had both h and glaucoma and 513 had glaucoma but no h. During the follow-up period hh were detected in 83 cases of glaucoma, and glaucoma developed in 27 cases with hh. The detection rate of hh among glaucoma was low but steady, indicating that hh may occur at any stage of the glaucoma process. This study shows no predilection for hh in cases with general hypertension or diabetes, nor is the frequency of hh among pseudoexfoliation cases significantly lower than among cases without this stigma.  相似文献   
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