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BACKGROUND: Pancreatic extracts are essential in the treatment of the majority of cystic fibrosis patients. The clinical response to different preparations is often unpredictable and at present there is no sure method of determining the best preparation for a particular patient. METHODS: Creon, Nutrizym GR, Pancrease and the high-lipase versions, Creon 25,000, Nutrizym 22 and Pancrease HL, were investigated for lipase content and resistance to simulated gastric conditions. The rates of lipase release in response to pH change, bile salts and duodenal solids were investigated. The stability of lipase and its binding to duodenal solids were also investigated. RESULTS: Declared values for lipase content were exceeded in all preparations. All preparations were acid resistant. The release of lipase in response to pH change showed notable differences in release rates. After 20 min at pH 5.5, Creon released three times the amount of lipase compared with Pancrease, the other preparations coming within the range. Above pH 5.75, the release rates were comparable amongst the preparations. Bile salts influenced release variably whilst release in a solid-rich duodenal fluid was much slower than in buffers. The released lipase was susceptible to proteolysis and pH-dependent binding to duodenal solids; these effects may compromise lipolysis. CONCLUSIONS: These results show some factors contributing to variable clinical responses to pancreatic supplements. Improvements may result if a patient is assessed on different preparations. 相似文献
994.
995.
Traumatic aortic lacerations are life-threatening injuries that require a prompt diagnosis and surgery if patients are to survive. Most authors recommend transfemoral catheterization when performing thoracic aortography in patients with suspected aortic lacerations. The authors of this study describe two patients in whom transfemoral catheterization and contrast material injection were directly related to their deaths. These cases illustrate the need for cautious catheter manipulation in patients with aortic lacerations. 相似文献
996.
目的:通过对牡丹根药效学和毒性的研究,为牡丹根的综合利用提供药理学依据。方法;采用比浊法,玻片法,观察牡丹根的凝血作用,耳肿法,足跖肿胀法和士的宁惊厥法,分别判断其抗炎及抗惊厥作用;同时对其降压作用和毒性进行测定。结果;大剂量15g/kg牡丹根在促进血小板聚集,抗炎,降压及抗惊厥方面均有显著的作用,与丹皮比较,无显著性差异。 相似文献
997.
Bertrand Garbay Michel Fournier Marie Line Sallafranque Sylviane Muller Françoise Boiron Anthony Heape Claude Cassagne Jacques Bonnet 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1988,8(2):91-107
We studied the quantitative changes in proteins (total, Po, MBP, and histones) and DNA from sciatic nerves of normal and Trembler mice during postnatal development. Polyacrylamide gel electrophoresis and immunoblotting procedures allowed an accurate characterization of Po, MBP, and histones, as well as the comparison of their respective amounts from d 2 to d 120 after birth. It was found that
- The immunoblotting procedure ascertains the presence of Po in the sciatic nerve of Trembler. In the 2-d-old mice, Po is detected in essentially similar amounts in Trembler and normal PNS, whereas its level in adult mutant sciatic nerves is never greater than 20% of the control. The sharp increase in Po levels observed during the third week in the normal nerves is not observed in those of the mutant;
- MBP species are at most 4% of the control in the 10- to 12-d-old Trembler mice, whereas they were not detectable in adult nerves. The distribution of the different MBP species is the same in both mutant and control mice;
- In normal mice, Po and MBP accumulate at similar rates, but the 14 kDa MBP accumulates faster than the 18.5 kDa MBP; and
- Histone and DNA contents decrease 3-to 5-fold in normal nerves, whereas they remain constant, or increase slightly, in the mutant.
998.
Despite a large amount of research of periodontal health seen in HIV infection, much remains to be learned. Very few large controlled studies of infected people at settings not self-selected for oral disease have been reported, and few have investigated the necrotising periodontal diseases described in HIV infection. In this paper we present a brief review of three approaches to identify periodontal changes associated with HIV infection and identify possible aetiological factors for them. First, we summarise the methods and findings of a controlled blinded study of the periodontal health of homosexual men attending a genito-urinary medicine clinic. Second, we précis a case-control study of gingival ulceration among patients at a dedicated dental clinic. Finally, we outline how the validity of diagnostic criteria for HIV-associated periodontal changes were tested against the data collected in the controlled study. 相似文献
999.
OBJECTIVE: Oral ulceration occurs in an estimated 2–4% of patients with HIV infection. This retrospective observational study describes the aetiology and characteristics of 94 HIV-positive patients with either severe and/or recurrent oral ulceration presenting at a dedicated HIV dental unit over a 4-year period. METHODS: Case records were reviewed for diagnosis investigations, CD4 count, CDC stage and treatment modality. RESULTS: Of the 94 patients 50% had an AIDS diagnosis. In patients with asymptomatic HIV disease minor recurrent oral ulceration was the commonest diagnosis whilst large non-specific neutropenic ulcers were more frequently seen in patients with symptomatic disease with low CD4 counts. A variety of treatment modalities were used including thalidomide. An algorithm is presented for the management of patients with severe oral ulceration. 相似文献
1000.