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91.
Assessment of carbohydrate tolerance in pregnancy   总被引:4,自引:0,他引:4  
A review is given of the various methods of assessing carbohydrate tolerance in pregnancy. Oral glucose tolerance screening and diagnostic tests have been in use for more than 25 years. They are easily administered, relatively inexpensive, and present reasonable sensitivity; therefore, they continue to be used quite extensively. However, lack of reproducibility of the results and side effects such as nausea, vomiting, and headache have led to the use of alternate methods including glucose polymer (Polycose) and standard breakfast meals. These methods have been reported to present satisfactory results in clinical practice. Glycosylated hemoglobin (HbA1c) and fructosamine assays are also alternate forms of testing carbohydrate metabolism HbA1c measurement have been proven insensitive as a screening test for gestational diabetes, while their use as an index of overall glucose control remains valuable. The role of fructosamine in the assessment of carbohydrate intolerance remains controversial with conflicting claims made by various investigators regarding its sensitivity in detecting gestational diabetes and its response to alterations in glycemic control. In this review, the relative advantages and disadvantages of each glucose tolerance test are discussed and recommendations are given regarding their utility in pregnancy.  相似文献   
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OBJECTIVE: To study the effect of the cervical plexus and the accessory nerve to the function of the trapezius muscle. STUDY DESIGN AND SETTING: Eighteen adult male Sprague-Dawley rats were randomly divided into three groups. The neurotomies were performed in the left sides and the right sides served as within-subject controls. In group A, the accessory nerve was transected. The C2-5 were transected in group B, and both of the accessory nerve and C2-5 were cut in group C. The electrophysiologic, myophysiologic, and histologic changes of the muscles were measured. RESULTS: There were significant differences (P < 0.05) between the three groups in the recovery rates of the transverse area of the muscles. The CMAP recorded from the experimental sides in group B were similar to the control sides. The values of the maximum tension of the tetanus contraction between the two sides showed no differences either (P > 0.05). CONCLUSION: The accessory nerve supplies the most important motor input to the trapezius. Motor innervations of the cervical plexus are not very significant.  相似文献   
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OBJECTIVE: To study how blood supply of the esophageal and gastric stumps influences the anastomotic healing after esophagogastrostomy in rabbits. METHODS: Twenty-seven New Zealand rabbits were randomly divided into 3 groups to receive esophagogastrostomy, followed by different procedures. Except for those in group I, all the rabbits were subjected to procedures of reducing the blood supply either of the esophageal or the gastric stump (group II and group III, respectively), followed by single-layer esophagogastric anastomoses using interrupted 5-0 polypropylene sutures. Ten days after operation, all the rats were killed and the anastomotic sites excised for measurement of the inner diameter, tensile strength, and hydroxyproline concentration. RESULTS: Healing of the esophagograstric anastomosis was obtained in all the rabbits but one with anastomotic leakage in group I and one with perforation of the gastric fundus in group III. The anastomotic inner diameters were similar in all the three groups, whereas the tensile strength and hydroxyproline concentration at the anastomoses decreased in group III in comparison with the other two groups (P<0.05) that had similar measurements (P>0.05). CONCLUSIONS: Extended length of the free esophageal stump does not significantly affect anastomotic healing as decrease of blood supply in the gastric stump.  相似文献   
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本文应用电力载波技术,实现远端时钟的中央控制。系统通过电力载波芯片从电力线上收发控制信号,中央控制端发送的时钟校准信号到电力线网络,接人网络的远端时钟接收到校准信号后,由微处理器解析数据调整受控端时钟显示,从而实现时钟的中央控制。  相似文献   
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