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21.
The influence of seven disinfectants on the dimensional stability of a base plate wax, Tenax, was studied. Two methods for treatment were tested - immersion for one hour and spraying respectively. After spraying no significant influence on the wax could be established and after immersion four of the seven disinfectants, including Cidex and K-644, likewise had no significant influence on the dimensional stability. The wax specimens did not show any significant weight increase (less than one per cent) after immersion for four days but in four disinfectant solutions the surface properties of the wax specimens had changed showing that active components of the disinfectants were absorbed into or adsorbed on the wax surface. 相似文献
22.
Lundin Pål D. P. Lundin Stefan Olsson Håkan Karlsson Börje W. Weström Björn R. Pierzynowski Stefan G. 《Pharmaceutical research》1995,12(10):1478-1482
Purpose. The present investigation was done to study the intestinal absorption of three oxytocin peptide analogues and to elucidate the role of pancreatic juice on their absorption.
Methods. In conscious chronically catheterized pigs (6–8 weeks of age) plasma concentration of the peptides, [Mpa1, D-Tyr(Ethyl)2, Thr4, Orn8]-oxytocin (F314), [Mpa1, D-Tyr(Ethyl)2, Val4, D-Arg8]-oxytocin (CAT), and [Mpa1, D-Tyr(Ethyl)2, Thr4, Orn8, desGly9, carba6]-oxytocin (F327) after intraduodenal administration, during presence or diversion of the pancreatic juice via a pancreatic duct catheter, were determined by radioimmunoassay. The stability of the peptides to degradation was determined in vitro by incubation with activated pancreatic juice, chymotrypsin or trypsin, followed by reversed phase HPLC analyses.
Results. All peptides were absorbed with a bioavailability of about 0.5% in the presence of pancreatic juice, but increased to 1.0%, 2.1%, and 13.5% for F314, CAT, and F327, respectively, when the pancreatic juice was diverted from the intestine. After incubation with pancreatic juice 95% of F314, 98% of F327, and 100% of CAT was found intact. When incubated with trypsin CAT remained intact while F314 and F327 were degraded by 54% and 46%, respectively. Incubation with purified chymotrypsin did not degrade the test peptides.
Conclusions. The results indicate that the increased absorption of peptides observed under conditions of diverted pancreatic juice cannot only be explained by the absence of pancreatic enzymes, but also by changed absorptive properties in the gastrointestinal tract. 相似文献
23.
Ivermectin for the chemotherapy of bancroftian filariasis: a meta-analysis of the effect of single treatment 总被引:4,自引:4,他引:0
Wu-chun Cao Catharina P. B. Van der Ploeg Anton P. Plaisier I. J. Sivera van der Sluijs J. Dik F. Habbema 《Tropical medicine & international health : TM & IH》1997,2(4):393-403
Summary The efficacy and safety of ivermectin in the treatment of filariasis due to Wuchereria bancrofti was assessed by a meta-analysis of the results from 15 published clinical trials. Seven hundred and forty-eight microfilaraemic patients were enrolled in 7 dose-finding and 8 comparative studies. Administered as a single dose, ivermectin induced nearly complete clearance of microfilariae from the blood from the first day to 30 days post-treatment, followed by gradual recurrence of microfilaraemia and increase in its intensity. Higher doses of ivermectin showed greater clearance effects and maintained lower microfilaraemia levels for a longer time. The adverse reactions caused by the drug were flu-like, transient, generally mild and well tolerated by patients. The frequency and intensity of adverse reactions were strongly associated with pretreatment microfilaria counts in the blood, but independent of dose. The findings of the meta-analysis suggest that ivermectin given at a single annual dose of 200 μg/kg body weight or higher, whether or not in combination with DEC, has great potential for therapeutic strategies to control bancroftian filariasis. 相似文献
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26.
In 50 partially edentulous patients, 133 (48 maxillary; 85 mandibular) Astra Tech dental implants of 2 different surface textures (machined; TiO‐blasted) were alternately installed, supporting 52 fixed partial dentures (FPDs). Before abutment connection 2 machined implants (1 mandibular; 1 maxillary) were found to be non-osseointegrated and were replaced. Another implant could not be restored due to a technical complication. Two FPDs were remade because of technical complications, both because of abutment fractures. Thus, after 2 years in function, the cumulative survival rates were 97.7% and 95.7% for implants and prostheses, respectively. There was no statistically significant difference in survival rate between the 2 types of implants, 100%(TiO‐blasted) vs 95.3%(machined), P =0.24. After 2 years in function, when both jaw and type of implants were combined, the mean (SD) marginal bone loss was 0.24 (0.69) mm. No statistically significant difference in bone loss was found between the 2 tvues of implant after 2 years of loading, 0.04 (0.82) mm, P >0.30. 相似文献
27.
Fractures after Stroke 总被引:6,自引:0,他引:6
A. Ramnemark L. Nyberg B. Borssén T. Olsson Y. Gustafson 《Osteoporosis international》1998,8(1):92-95
Fractures are a serious complication after stroke. Among patients with femoral neck fractures, a large subgroup have had
a previous stroke. This study aimed to investigate the incidence of fractures after stroke. Included in the study were 1139
patients consecutively admitted for acute stroke. Fractures occurring from stroke onset until the end of the study or death
were registered retrospectively. Hip fracture incidence was compared with corresponding rates from the general population.
Patients were followed up for a total of 4132 patient-years (median 2.9 years). There were 154 fractures in 120 patients and
median time between the onset of stroke and the first fracture was 24 months. Women had significantly more fractures than
men (χ2 = 15.6; p < 0.001). In patients with paresis most of the fractures affected the paretic side (χ2 = 22.5; p < 0.001) and 84% of the fractures were cause by falls. Hip fracture was the most frequent fracture and the incidence was
2–4 times higher in stroke patients compared with the reference population. Fractures are thus a common complication after
stroke. They are usually caused by falls and affect the paretic side. It is necessary to focus on the prevention of post-stroke
fractures, including the prevention of both falls and osteoporosis. 相似文献
28.
Twenty-four hour profiles of free insulin and blood glucose were determined in 12 healthy controls and 10 insulin-dependent diabetics treated with insulin regimens based on intermediate-acting insulin injected subcutaneously once or twice a day. The diabetics were ambulatory and in a good glycemic control, i.e. without hyperglycemic symptoms or frequent hypoglycemias and with HbA1 less than 9% (reference value 5.9-7.8%). Body weight was normal and median age (32 years) was the same in both groups. Free insulin was determined after polyethylene glycol precipitation of antibody-bound insulin. The controls had a low basal insulin level (median fasting value 3.9 mU/l) and postprandial peaks with a maximum within 30-60 min. There was no rise in plasma free insulin or blood glucose in the early morning hours. The free insulin profiles in the diabetics were highly unphysiological with hyperinsulinemia between the meals and during the night. The highest plasma free insulin value during the 24 hours was reached before lunch (approximately 5-fold compared to normals, p less than 0.01). Postprandially the free insulin concentrations did not reach the peak levels of the normals. After breakfast, blood glucose rose considerably in the diabetics (p less than 0.02 compared to normals) while the rise after lunch and dinner was not higher than in the healthy controls. The difficulties in glycemic control in the diabetic group, i.e. a blood glucose rise after breakfast and hypoglycemias in some patients, could largely be explained by the unphysiological insulin profiles. 相似文献
29.
30.
Production and release of lymphotoxin (LT) was studied by metabolic labeling of human B- and T-cell lines with 14C-leucine and 35S-methionine. LT was immunoprecipitated with antiserum to LT and separated by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) followed by fluorography. Two molecular weight forms of LT with different rates of release were found both in cell supernatants and cell extracts. Monensin, a sodium ionophore, inhibited the release of LT. LT still appeared in two molecular weight forms after deglycosylation with N-glycanase. Treatment of cells with swainsonine followed by digestion of released LT with endoglycosidase H (endo H) demonstrated that the oligosaccharides were of the complex type. Subcellular fractionation of cells on Percoll density gradients demonstrated that intracellular LT is located to intermediate density fractions. No LT was found in the high density fractions corresponding to lysosomes. Phorbol 12-myristate 13-acetate induced production of tumor necrosis factor (TNF) in the B-lymphoblastoid cell line RPMI-1788. In conclusion, we have demonstrated the presence of two distinct molecular weight forms of LT, which contain N-linked oligosaccharides of the complex type. 相似文献