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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
R G Rees J J Payne-James C King D B Silk 《JPEN. Journal of parenteral and enteral nutrition》1988,12(5):469-472
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
993.
A. Biglino M. Depaoli G. Cariti D. Giacobbi P. Gioannini 《European journal of epidemiology》1988,4(2):246-250
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
994.
995.
996.
997.
D Bild L S Geiss S M Teutsch B Gabella B A Hudspeth R M Schubert C W Gollmar D J Kaplan F A Connell J C Will 《Journal of clinical epidemiology》1988,41(10):999-1006
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
998.
Internal eye wall resection in the management of uveal melanoma 总被引:3,自引:0,他引:3
G A Peyman H Charles 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》1988,23(5):218-223
Twenty patients with presumed uveal melanoma underwent internal eye wall resection. It was the primary procedure in 13 patients who had tumours within 2 disc diameters of the optic nerve head and was combined with external resection in the remainder. Malignant melanoma was confirmed histologically in 15 patients; the diagnosis was a benign tumour in the other 5. The length of follow-up ranged from 2 to 37 (mean 19) months. In all cases the retina was completely attached at the time of last examination. The visual acuity ranged from 20/40 to hand movements; nine patients had an acuity of 20/400 or better. At the time of writing no metastatic disease or local recurrence had developed in any of the 15 patients in whom malignant melanoma was diagnosed. 相似文献
999.
G. H. M. B. Van Rens 《Documenta ophthalmologica. Advances in ophthalmology》1988,70(2-3):205-208
The Q-switched neodymium-YAG laser was used via a transconjunctival approach to reopen a failed filtering bleb, 6 weeks after a primarily successful trabeculectomy had failed. One day after treatment, the intraocular pressure had decreased from 34 mm Hg to 17 mm Hg, and a conjunctival bleb had reformed. 相似文献
1000.
Antisera have been made to synthetic peptides that correspond to eight different regions of the alpha A molecule. Together with a solid phase radioimmunoassay, these antisera have been used to quantitatively assess binding to enriched alpha crystallin preparations from six different cataractous and six different normal lenses. Seven of the eight antisera show no difference in binding to alpha crystallin from cataractous versus normal lenses, whereas the antiserum directed against the alpha A sequence 120-130 shows a statistically significant decrease in binding to the alpha crystallin from cataractous lenses. Together, these studies demonstrate the feasibility of using antipeptide sera as probes of polypeptide changes during cataractogenesis and suggest that the region of the alpha A crystallin molecule encompassing residues 120-300 may undergo covalent and/or noncovalent structural modification during the process of opacification in the human senile lens. 相似文献