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11.
BACKGROUND & AIMS: Nutrients and properties of lipases affect survival of lipolytic activity during aboral gastrointestinal transit. Whether different doses and formulations of bacterial lipase and diets affect steatorrhea was tested in pancreatic-insufficient dogs. METHODS: A dose of 0-600,000 IU of powdered and 135,000 and 300,000 IU of liquid bacterial lipase was given with a standard meal to 5 dogs with ligated pancreatic ducts. In 4 dogs, 0 or 300,000 IU (normal 6-hour postprandial amount) of powder bacterial lipase was also given with five meals containing 850 kcal with different nutrient caloric densities (mixture design). Coefficients of fat absorption during 72- hour fecal balance studies were used to assess treatments. RESULTS: With the standard meal, powder bacterial lipase reduced steatorrhea in a dose-dependent manner (P = 0.03), and 135,000 and 300,000 IU of the liquid form decreased steatorrhea more than powder bacterial lipase (P = 0.017 and 0.057, respectively). Coefficients of fat absorption with 300,000 IU of powder bacterial lipase correlated (r2 = 0.79; P < 0.001) with increasing proportions of fat calories in diets. CONCLUSIONS: Liquid bacterial lipase decreases steatorrhea more than powder, and 300,000 IU of powder bacterial lipase ingested with high-fat meals corrects canine pancreatic steatorrhea. The combination of adequate mixing of small amounts (milligrams) of bacterial lipase and high-fat meals abolishes canine steatorrhea and may abolish human pancreatic steatorrhea. (Gastroenterology 1997 Jun;112(6):2048-55) 相似文献
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A Aronstam B Congard DI Evans CF Gazengel U Herberg FG Hill PM Jones R Ljung EP Mauser-Bunschoten E Scheibel 《Archives of disease in childhood》1993,68(4):521-524
Ten haemophilia centres in northern Europe have pooled data on 202 haemophilic children who were infected with HIV between 1979 and 1986. All cases were under 16 years of age on 1 July 1985. The age at infection ranged from 1-15 years. Thirty seven cases (18%) had progressed to AIDS by 1 July 1991 and 15 of these have died. Persistent generalised lymphadenopathy has been noted in 102 patients of whom 18 (17%) have developed AIDS. Twenty three of the remaining patients (23%) have not. CD4+ T cell counts have fallen steadily. Of 36 patients who have had shingles since seroconversion, 19 (53%) had counts below 0.2 x 10(9)/l. Thirty five out of 145 patients without shingles (24%) had similar values. The mean IgA concentration in patients with CD4+ T cell counts above 0.5 x 10(9)/l was 2.38 g/l, between 0.2 and 0.5 was 3.07 g/l, and in those with CD4+ T cell counts below 0.2 x 10(9)/l the mean IgA concentration was 4.58 g/l. Treatment patterns have altered between 1989 and 1991, with increased use of zidovudine in patients without AIDS and a marked increase in primary prophylaxis against pneumocystis pneumonia. This has been associated with a decline in the incidence of pneumocystis as an indicator disease in new AIDS cases from 56% in 1989 to 20% in 1991. These observations indicate that persistent generalised lymphadenopathy does not worsen the outlook, but shingles does. Rising IgA concentrations are markers for disease progression. Modern prophylactic regimens are delaying the onset of indicator disease, but CD4 values continue to fall steadily. 相似文献
14.
Direct demonstration of transsynaptic degeneration in the human visual system: a comparison of retrograde and anterograde changes 总被引:1,自引:0,他引:1 下载免费PDF全文
RM Beatty AA Sadun LEH Smith JP Vonsattel EP Richardson Jr 《Journal of neurology, neurosurgery, and psychiatry》1982,45(2):143-146
Transneuronal degeneration of retinal ganglion cells was directly demonstrated in a patient who had unilateral removal of the striate cortex forty years prior to necropsy. For comparison, another case is presented showing anterograde transneuronal atrophy forty years after enucleation of one eye. 相似文献
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Perforation complications of percutaneous central venous catheters in very low birthweight infants 总被引:2,自引:0,他引:2
OBJECTIVE: To prospectively survey perforation complications of consecutively inserted percutaneous central venous catheters (PCVC) in very low birthweight (VLBW) infants over a 2 year period. METHODOLOGY AND RESULTS: Three serious perforation complications were encountered in a series of 100 consecutive PCVC. One infant (birthweight 685 g) developed pericardial effusion and fatal cardiac tamponade during the use of a polyurethane PCVC. At autopsy, the pericardial sac contained 8 mL fluid with a glucose concentration of 109 mmol/L and the catheter tip was embedded in the right ventricular wall. The second infant (birthweight 1380 g) showed pleural effusion and transient immobility of the right diaphragmatic leaf after perforation of a similar PCVC into the right pleural cavity. The third perforation, causing subcutaneous oedema, occurred in a 655 g infant who had a silastic PCVC. CONCLUSIONS: The data suggest a 3% incidence for PCVC-associated symptomatic perforation complications and a 1% incidence for fatal perforations, despite a policy of careful placement. The data also indicate that perforation complications occur regardless of the size or material of the PCVC. Proper visualization of the PCVC and vigilant attention to its location is required to prevent these rare but potentially fatal complications. 相似文献
17.
Greenough A Dimitriou G Bhat RY Broughton S Hannam S Rafferty GF Leipälä JA 《European journal of pediatrics》2005,164(9):583-586
New bronchopulmonary dysplasia (BPD) has been suggested to be a maldevelopment sequence with reduced alveolarisation of the lungs; affected infants then would be predicted to have low lung volumes. The aim of this study was to test that hypothesis by comparing the lung volumes of infants who had had mild-moderate BPD with those without BPD of similar postmenstrual age. Lung volumes of 17 infants who had mild-moderate BPD (oxygen dependent beyond 28 days, but not past term) (BPD infants) were compared to those of 17 infants without BPD (non-BPD infants). All were born at less than 33 weeks of gestation and studied at postmenstrual ages of 33 to 39 weeks. Lung volume was assessed by measurement of functional residual capacity (FRC). The BPD infants had lower lung volumes (median 19.1 ml/kg) than the non-BPD infants (median 26.5 ml/kg) (p=0.0001). The BPD compared to the non-BPD infants were of greater postnatal age (p=0.0003), born at a lower gestational age (p=0.0001) and of lighter birthweight (p=0.0001). Regression analysis, however, demonstrated that lung volume was significantly related to BPD status (p=0.005), independently of postnatal age, birthweight and gestational age. It is concluded that the lower lung volumes of the infants who had had mild-moderate BPD support the hypothesis that new BPD is associated with poor alveolarisation. 相似文献
18.
Flexible tantalum stents implanted in aortas and iliac arteries: effects in normal canines 总被引:2,自引:0,他引:2
Barth KH; Virmani R; Strecker EP; Savin MA; Lindisch D; Matsumoto AH; Teitelbaum GP 《Radiology》1990,175(1):91-96
Vascular endoprostheses made of knitted tantalum wire and expanded over angioplasty balloons were placed into aortas or iliac arteries of 14 normal dogs. Twelve stents were placed into the infrarenal abdominal aorta and two stents in the left common iliac arteries by the left carotid artery approach. To firmly expand the stent against the vascular wall, nominal stent sizes 0.5-1.0 mm larger than the measured arterial diameter were required. Arteriography performed at specified follow-up intervals showed no evidence of thrombi or emboli; all side branches (lumbar arteries) covered by the stents remained patent. Vascular diameter decreased minimally at 8 and 26 weeks, associated with histopathologic evidence of neointimal buildup. This buildup was highest at 8 weeks (mean, 313 microns) and was slightly less at 26 weeks (mean, 223 microns). Almost complete coverage by endothelium was seen as early as 3 weeks. It is concluded that the flexible tantalum wire stents are well tolerated by the arterial wall and become quickly endothelialized. No excessive neointimal buildup was observed during the 6-month study. 相似文献
19.
Lloyd-Jones DM Wilson PW Larson MG Leip E Beiser A D'Agostino RB Cleeman JI Levy D 《Archives of internal medicine》2003,163(16):1966-1972
BACKGROUND: We sought to assess how cholesterol levels at different ages modify the remaining lifetime risk of coronary heart disease (CHD). METHODS: We included all Framingham Heart Study participants examined from 1971 through 1996 who did not have CHD and were not receiving lipid-lowering therapy. At index ages of 40, 50, 60, 70, and 80 years, participants were stratified by total cholesterol level and by cholesterol subfractions. Lifetime risk of CHD was calculated with death free of CHD as a competing event. RESULTS: Among 3269 men and 4019 women, 1120 developed CHD and 1365 died free of CHD during follow-up. At each index age, lifetime risk of CHD increased with higher cholesterol levels, and time to event decreased. At age 40 years, the lifetime risks of CHD through age 80 years for men with total cholesterol levels less than 200 mg/dL (<5.20 mmol/L), 200 to 239 mg/dL (5.20-6.19 mmol/L), and 240 mg/dL or greater (> or =6.20 mmol/L), respectively, were 31%, 43%, and 57%; for women, the lifetime risks were 15%, 26%, and 33%, respectively. Lifetime risks contrasted sharply with shorter-term risks: at age 40 years, the 10-year cumulative risks of CHD were 3%, 5%, and 12% for men, and 1%, 2%, and 5% for women, respectively. CONCLUSIONS: Lifetime risk of CHD increases sharply with higher total cholesterol levels for men and women at all ages. These data support an important role for cholesterol screening in younger patients, and they may help target high-risk patients for lifestyle modification or drug therapy. 相似文献
20.
Molecular heterogeneity has a major impact on the measurement of circulating N-terminal fragments of A- and B-type natriuretic peptides 总被引:7,自引:0,他引:7
Ala-Kopsala M Magga J Peuhkurinen K Leipälä J Ruskoaho H Leppäluoto J Vuolteenaho O 《Clinical chemistry》2004,50(9):1576-1588
BACKGROUND: The N-terminal fragments of A- and B-type natriuretic peptides (NT-proANP and NT-proBNP) are powerful markers of cardiac function. The current assays require refinement with regard to standardization with native calibrators and the ability to detect the actual circulating forms. METHODS: The following peptides were prepared with recombinant methods: NT-proANP, NT-proBNP, proBNP1-108, and Tyr0-proBNP77-108. Fifteen peptides of 13-22 amino acids, spanning the sequences of NT-proANP and NT-proBNP, were prepared by solid-phase peptide synthesis. Two immunoassays for NT-proANP and four for NT-proBNP were set up, each with a different epitope specificity. The assays were applied for the measurement of NT-proANP and NT-proBNP in healthy individuals and in patients with acute myocardial infarction. The circulating molecular forms were analyzed by gel-filtration and reversed-phase HPLC. RESULTS: According to the HPLC analyses, circulating NT-proANP consists mainly of the full-length peptide, with some degradation at both ends. In contrast, circulating NT-proBNP is very heterogeneous. Most immunoreactive NT-proBNP is significantly smaller in size than NT-proBNP1-76, with truncation at both termini. The smallest fragments can be detected by assays directed at the central part of NT-proBNP only; assays directed at the ends gave 30-40% lower values. Despite the difference, the various assays correlated reasonably well with each other (r2 = 0.77-0.85). In patients with acute myocardial infarction, NT-proANP and NT-proBNP concentrations were 1.8-2.3 and 4.2-4.5 times higher than in healthy individuals. The development of heart failure further increased the concentrations. CONCLUSIONS: Molecular heterogeneity of the circulating forms causes a serious risk of preanalytical errors in assays for NT-proBNP and, to a lesser extent, NT-proANP. The development of a sandwich assay for NT-proBNP would be especially challenging. The most robust and reliable assays use antibodies directed at the central portions of NT-proANP or NT-proBNP. 相似文献