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991.
Plasma pyridoxal-5'-phosphate and pyridoxal levels increased significantly (p less than 0.05) when single, oral bolus doses of pyridoxine were increased from 10 to 25 and from 25 to 50 mg in nine female volunteers. However, when the dose was increased to 100 mg, plasma pyridoxal-5'-phosphate levels did not differ significantly from those recorded after the 50 mg dose. Within 3 h plasma pyridoxal levels rose with a factor of 3.85 compared with the 50 mg dose but high pyridoxal levels were eliminated from the circulation. Renal clearance of pyridoxal remained a constant, low percentage (less than 2.0%) of each pyridoxine supplement in spite of the observed very high circulating pyridoxal levels. Pyridoxine supplementation is discussed in relation to circulating pyridoxal-5'-phosphate and pyridoxal availability for cellular metabolism.  相似文献   
992.
About 85% of the population of two Somali communities harboured soil-transmitted intestinal nematodes and/or protozoa. The commonest parasite (75% in the Lafoole institution and 59% in the Afgoye institution) was Trichuris trichiura. Mixed infections were common. The source of infection is contaminated fields around dwelling quarters, because of indiscriminate defaecation. One of the factors responsible for the higher incidence of hookworm in Lafoole (45%) compared with Afgoye (1.5%) may be the different soil character of the surrounding fields.  相似文献   
993.
We have compared the effects of acetyl salicylic acid (ASA, aspirin) and choline magnesium trisalicylate (CMT), a non-acetylated salicylate product, on platelet aggregation in human whole blood ex-vivo. Using a whole blood platelet counter, platelet aggregation was quantified by measuring the fall in the number of single platelets at peak aggregation in response to collagen, arachidonic acid (AA), as well as spontaneous aggregation. In double blind and random order, 12 healthy volunteers received, on two separate occasions 10 days apart, a single oral dose of 652 mg ASA or 655 mg CMT. Despite a comparable absorption of salicylic acid from the two drugs, ingestion of ASA resulted in a marked inhibition of platelet aggregation induced by collagen (p less than 0.005), AA (p less than 0.01) and spontaneous aggregation (p less than 0.01), whereas such effects were not observed after CMT ingestion. We suggest that CMT may have therapeutic potential as an alternative to aspirin when inhibition of platelet aggregation can induce bleeding complications.  相似文献   
994.
Ileoanal reservoir for ulcerative colitis and familial polyposis   总被引:20,自引:0,他引:20  
Although total proctocolectomy with permanent ileostomy is regarded as the definitive therapy for ulcerative colitis and familial polyposis, psychologic and physical complications with this operation have stimulated the development of the operation of total abdominal colectomy, mucosal proctectomy, ileal reservoir, and ileoanal anastomosis as an alternative surgical procedure. Since 1980, 104 of these operative procedures have been completed with no operative mortality; experience has been gained with both the J- and S-type reservoirs. Despite an appreciable number of postoperative complications, satisfactory function of the reservoir has been achieved in 86 of 91 patients followed up for at least three months after closure of the ileostomy. The remaining five patients have required reinstitution of fecal diversion. Functional results have not differed between two-limbed and three-limbed reservoirs. This operation must be considered a viable alternative in patients with ulcerative colitis and familial polyposis.  相似文献   
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The glucose-clamp technique was used to assess the effect on insulin activity of mixing clinically relevant doses of short- and longer-acting insulins in insulin-treated diabetic subjects. Mixtures of porcine regular and lente insulins resulted in a reduction in activity of the mixture compared with separate injection that was more apparent with premixing for 5 min before injecting than with premixing for 2 min. These findings were not explained by differences in volume of the injected insulin preparations. Mixing of porcine regular and bovine ultralente insulins for 2 min before injecting resulted in a reduced activity compared with separate injection. No difference in activity was obvious for porcine regular and NPH insulins given separately or premixed for 5 min. A reduction of activity during the 1st h after injection was observed when separate injection of one brand of these insulins (Velosulin or Insulatard) was compared with the manufactured mixture (Mixtard). These results indicate that premixing regular and NPH insulins in a 1-to-2 ratio does not alter the biological activity compared with separate administration of the insulins. However, the mixing of regular and insulin-zinc suspensions results in a loss of insulin activity, the magnitude of which depends on the time between mixing and injecting the insulin. The clinical significance of the effect of mixing on the efficacy of subcutaneous insulin therapy should be considered in the context that this is only one of many factors that may affect the activity of subcutaneously injected insulin.  相似文献   
1000.
Conclusion Although more data are needed and it is still too early for a definitive conclusion, GIFT can probably offer new perspectives not only in the treatment of unexplained infertility but also in cases of persistent infertility in patients with LUF (luteinzed unruptured follicle) or a mild degree of endometriosis or when no conception occurs after surgical correction of endometriosis.Only further prospective studies will help us to determine the indications for GIFT.  相似文献   
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