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21.
Platelet-activating factor induces the expression of early pregnancy factor activity in female mice 总被引:3,自引:0,他引:3
When synthetic platelet-activating factor (PAF, 1-0-alkyl-2-acetyl-sn-glycero-3-phosphocholine) was injected into mature female mice during dioestrus, pro-oestrus or oestrus, it induced the expression of early pregnancy factor (EPF) activity in the sera of these animals within 1 h of injection. The sera of similarly injected males, metoestrous or immature females did not display any EPF activity. The results suggest that embryo-derived PAF may be the ovum factor responsible for triggering the generation of serum EPF activity during the preimplantation stages of pregnancy. 相似文献
22.
R. J. Clarke D. Lincoln Lewis J. Alexander Williams 《BMJ (Clinical research ed.)》1972,2(5810):369-371
In a series of 68 patients with gastric ulcer who were treated by vagotomy and pyloroplasty there were no operative deaths, though one patient who received massive transfusions died 14 weeks later from hepatic necrosis probably associated with serum hepatitis. Four patients developed recurrent peptic ulceration requiring further surgical treatment. The clinical condition of all but three of the remainder was satisfactory after an average follow-up period of three years and two months. Of the 14 patients who presented with an acutely bleeding gastric ulcer, one subsequently required gastrectomy for continued bleeding; in all the others the immediate and long-term results were satisfactory. Of 21 patients with a “high” ulcer and 29 with combined gastric and duodenal ulceration one (4·8%) and three (10%) respectively suffered recurrences. We conclude that vagotomy and pyloroplasty is a satisfactory form of treatment for a high or bleeding gastric ulcer, but that for all other gastric ulcers some form of gastric resection is preferable. 相似文献
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A common theme in the amino acid sequences of actin and many actin-binding proteins? 总被引:9,自引:0,他引:9
The amino acid sequences of several actin regulatory proteins have recently been determined. Do these proteins function by mimicking actin-actin interaction sites? 相似文献