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991.
992.
Back pain in in-vitro fertilized and spontaneous pregnancies   总被引:1,自引:0,他引:1  
The influence of ovarian stimulation in in-vitro fertilization (IVF) on the prevalence of back pain with onset during pregnancy was studied in 31 women who became pregnant after IVF treatment and compared with that of 200 spontaneously pregnant women. A two times higher prevalence rate of sacral pain in late pregnancy was reported among IVF pregnant women (P < 0.0001), as well as a significantly higher prevalence rate of positive results of pelvic pain provocation tests performed in late pregnancy (0.0001 < or = P < or = 0.015), as compared with that of the spontaneously pregnant women. Among the IVF pregnant women, there was a significant positive correlation between relaxin concentrations in early pregnancy and the outcome of pelvic pain provocation tests (0.44 < or = r < or = 0.51, P < 0.05). In addition, the serum relaxin concentration was the factor that best explained differences in sacral pain prevalence. When the influence of serum relaxin concentration on back pain prevalence was taken into account, women carrying multiple pregnancies had no more pain than women carrying singletons, and IVF pregnant women had no more pain than spontaneously pregnant women. These results support the hypothesis that relaxin is involved in the generation of pelvic pain in pregnant women.   相似文献   
993.
994.
Phonetics, esthetics, function, and comfort form the foundation of a successful dental prosthesis. A review of the mechanics of speech as well as common speech problems encountered with a removable maxillary prosthesis are presented. The use of a palatogram to aid the clinician in the assessment and resolution of speech problems associated with a maxillary denture is demonstrated.  相似文献   
995.
Bilateral germ cell tumours of the testis are rare but a rise in their incidence is expected since with the new therapeutic possibilities a significant improvement in prognosis has been achieved even in patients with advanced metastatic spread. Of the 210 patients treated for malignent germ cell tumours at our Department, six (2.9%) developed a contralateral testicular tumour. All patients had metachronous tumours and the second tumours occurred after an interval ranging between 1 and 22 years. The epidemiology, histology, diagnosis, therapy and prognosis are discussed, and the significance of regular self-examination of the remaining testis in patients with testicular tumour is emphasized.  相似文献   
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The high cost of commercial CT-compatible stereotactic frames has restricted the availability of CT-guided stereotaxy for many neurosurgical centres. However, many of these centres do possess the standard stereotactic frames for projection radiography, of which the old type Leksell frame is probably the most common. We have devised a simple and low-cost modification to an old Leksell frame to allow CT-guided stereotaxy. The nature of the modifications allow complete freedom of positioning of the frame relative to the CT scanner and coordinate transformations can be performed simply and effectively. The modified frame has been used successfully for some 18 months and the modification has now been performed at two centres in the North West Regional Health Authority. We hope this modification will allow many other centres to embark on CT-guided stereotaxy.  相似文献   
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