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While less emphasis has traditionally been placed on aesthetics in order to focus on successful osseointegration, increased success rates provided by contemporary endosseous root-form dental implants have improved postoperative peri-implant hard and soft tissue structures. The criteria for the evaluation of implant success should, therefore, include lack of pain, mobility, radiolucency, bone loss, infection, or paresthesia, as well as acceptability and stable aesthetics. This article discusses surgical means to preserve or restore hard and soft tissues around dental implants to achieve ideal and predictable outcomes.  相似文献   
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After previous preliminary observations of paradoxical deletion events affecting the inactive X chromosome in melanoma, we have surveyed the X chromosome for deletions using 23 polymorphic microsatellite markers in 28 informative (female XX) metastatic melanomas. Ten tumors (36%) showed at least one loss of heterozygosity (LOH) event, and in two cases an entire chromosome showed LOH at all informative loci. Four distinct X chromosome smallest regions of overlap can be resolved. An 18.6-Mb region on the p arm involving 9 of 28 (32%) samples lies between the markers DXS1061 and DXS1068. An equally frequently deleted smallest region of overlap straddled the centromere, bounded by DX1204 on the p arm and DXS983 14.6 Mb away in Xq11-12. One tumor potentially defines this region more tightly to a 10.6-Mb smallest region of overlap bounded by DXS1190 and DXS981 that contains the androgen receptor (AR) gene. A 6.2-Mb deleted region can be defined between the markers DXS8051 and DXS9902 in 8 of 28 (28%) tumors. An additional, less frequently deleted region of 25.7 Mb was found on distal Xq between the markers DXS1212 and DXS1193 in 5 of 28 (18%) tumors. X inactivation analysis of five tumors with LOH, using the AR exon 1 CAG repeat, showed that in each case, the inactive, hypermethylated allele was the one deleted. Analysis of copy number in this region by quantitative PCR showed restoration to disomy and, in one case, trisomy at AR.  相似文献   
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Postoperative pain control can be unsatisfactory for a variety of reasons, including patients' attitudes towards pain treatment itself. To assess patients' expectations and their influence on postoperative analgesia, as well as the prevalence of pain following common gynaecological surgery, a prospective study was performed in 166 patients with either adbominal hysterectomy, mastectomy, laparoscopy or uterine curettage. After a first postoperative period with routine on-demand analgesia, a nurse specialised in pain treatment discussed the purposes and risks of pain treatment with the patients and cared for these patients in the second, subsequent study period. Following this discussion, 30 of 40 patients refusing analgesics in the first study period agreed to be given pain medication. In the groups with hysterectomy or mastectomy, pain control improved in the second postoperative period, even though the doses of analgesics administered were generally lower. Education of patients regarding the aims and risks of pain therapy is an essential part of pain control and can lead to an improvement of postoperative analgesia.  相似文献   
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The anticarcinogenic effect of the dietary antioxidant butylated hydroxytoluene (BHT) correlates with a preservation of nuclear envelope (NE) cytochrome P-450 in rats undergoing chemically induced hepatocarcinogenesis. This effect of BHT on NE cytochrome P-450 was observed during both the initiation and the promotion stages of hepatocarcinogenesis. Complex interactions between the two different mechanisms of action of BHT (i.e., enzyme induction and antioxidant activity) may account for some of the differences between the patterns of response to BHT observed during initiation and promotion.  相似文献   
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Summary Partial anomalous pulmonary venous connections (PAPVCs) are rare in association with an intact atrial septum. However, the diagnosis should be considered in patients with otherwise unexplained findings of left-to-right shunt and right heart enlargement. An unusual variant is presented, which we considered unsuitable for operative repair, based on findings at catheterization. Developmental, hemodynamic, and surgical considerations are discussed.  相似文献   
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