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21.
Treatment of juvenile patients with a missing maxillary incisor is difficult, because an implant cannot be placed until growth is completed. The other minimally invasive alternatives are also problematic: Removable dentures are rarely accepted by juvenile patients, and the conventional resin-bonded fixed partial denture often provides a poor esthetic result because the metal retainer causes the abutment teeth to lose their natural translucency and to become grayish. Moreover, the alveolar ridge defect makes it easy to identify the prosthesis in the pontic area. The present case report describes the prosthetic treatment of a juvenile patient who had lost a maxillary incisor to trauma. To avoid the disadvantages of conventional therapies, subepithelial connective tissue was grafted to reshape the alveolar ridge. The space was closed with an all-ceramic resin-bonded fixed partial denture.  相似文献   
22.
BACKGROUND: Until recently, there has been no practical alternative to the use of calcineurin inhibitors (CIs) as primary immunosuppressants in lung transplantation (LTx) and heart transplantation (HTx). Sirolimus (SRL) is a novel powerful immunosuppressant without renal toxicity, a common post-transplant problem associated with CI therapy. METHODS: SRL was used in 20 LTx and 5 HTx recipients >90 days post-transplant, where serious renal impairment was limiting CI dosing. Patients started on 2 to 5 mg/day orally at a median of 1,185 days post-transplant. Dosage adjustments were made according to trough levels, toxicity and perceived efficacy. With SRL initiation, 48% ceased CI therapy and the remainder decreased their dose substantively. RESULTS: After 30 days, 4 of 5 dialyzed patients ceased dialysis and 15 of 20 patients with an elevated serum creatinine (Cr) (mean Cr 0.29 mmol/liter) improved their Cr. The direction of change in Cr at 30 days predicted longer term Cr. The starting Cr did not predict the 30-day or long-term value. There were two bouts of acute and one bout of chronic rejection. There were 35 infectious complications in 16 patients and 24 episodes of potential SRL-related toxicity in 17 patients. These events generally responded to dose reduction or temporary cessation and were level-related. Fifteen recipients presently remain on the drug. None of the 7 deaths could be directly related to toxicity. CONCLUSION: SRL is a useful alternative immunosuppressant, allowing significant CI withdrawal in transplant recipients with renal impairment. Whether the resulting improvement in Cr can be maintained in the long term probably depends on the balance between the extent of acute and chronic renal damage.  相似文献   
23.
本文探讨食管胃腔内弹力环扎吻合术的力学机理。这是一种不用任何缝合材料或吻合器进行胃食管吻合的新技术,我们已成功应用于临床。取临床所用的乳胶管按该材料多向异性特征、实验条件以及弹力环数目分为8组,每组3个样品进行各种体外力学试验。通过应力—应变(拉力—伸长)关系曲线和定伸长松驰试验确定它的力学特性是一种粘弹性材料。根据实验所得的应力换算为弹力环对食管和胃组织所施加的最佳压力(压强)是4.23±0.23Kg/cm~2,这样才能保证这一种新颖的吻合术可达到简便、安全、可靠的目的。  相似文献   
24.
考察了褐煤离子交换处理前后的加氢液化性能,探讨了不同形态铁催化剂和不同溶剂对褐煤加氢液化的影响。发现在液化反应条件下,离子交换煤中的(RCOO)_3Fe分解为Fe_3O_4,后者在有较高供氢性能的溶剂中和有硫存在的条件下进一步转化为Fe_(1-x)S,其催化活性高于Fe_3O_4。此外,在液化残渣的Mossbauer谱中发现有γ-Fe,它可能是由Fe_(1-x)S还原而成,其催化活性比Fe_(1-x)S更高。  相似文献   
25.
目的 观察白术桃花汤治疗习惯性便秘的疗效。方法 自拟白术桃花汤 (白术 30g ,桃花 12g ,生地黄 30g ,枳实 10g) ,每日服 1剂 ,7d为 1个疗程。对照组服用果导片作对比观察。结果 白术桃花汤治疗习惯性便秘 117例 ,治愈 10 6例 ,好转 4例 ,总有效率 94 .0 2 %;果导片治疗 6 6例 ,治愈18例 ,好转 30例 ,总有效率 72 .73%。两组总有效率比较 ,经统计学处理P <0 0 1,差异有非常显著性意义。结论 白术桃花汤功能为补气除湿 ,增液行气 ,通调大便 ,治疗习惯性便秘疗效满意。  相似文献   
26.
Summary Aims This study investigated the early and mid–term results following valve replacement with the new Shelhigh? stentless bioprosthesis made entirely of biological material in patients with active infective endocarditis (AIE). Material and methods Between 02/2000 and 12/2004, 164 patients (n = 122 men, mean age 59, 18–85 years) received implantation of an AIE Shelhigh? stentless bioprosthesis in the aortic, mitral, tricuspid or pulmonary position. A total of 119 patients (72.6%) had native AIE and 45 (27.4%) prosthetic AIE. A large proportion of the patients reached the operating room in a condition of cardiac decompensation: 37 (22.6%) patients were intubated, 40 (24.4%) had protracted septic shock and 41 (25.0%) required intensive catecholamine treatment. Surgery was regarded as urgent in 94 patients (57.4%) and was performed as an emergency procedure in 70 (42.6%). The mean follow–up time is 1.5 ± 0.11 years (range, 5 months to 5.2 years). Echocardiographic follow–up examinations were performed early postoperatively and after 12 months. Results In terms of the operative indication, we found a highly significant difference in the survival rate between patients who were operated on urgently vs in an emergency. In patients who died within 30 days, the main cause of death was septic multiorgan failure (67.6%). Only three patients required reoperation due to reinfection of the Shelhigh? bioprostheses; this represents a reinfection rate of 1.8% in relation to the whole cohort. The postoperative echocardiographic examinations showed the Shelhigh? valves to have very good hemodynamics without relevant pressure gradients. Conclusion Our experience in the use of Shelhigh? bioprostheses in patients with native and prosthetic endocarditis show the early and mid–term results, in particular the low reinfection rate and the good hemodynamics, to be comparable with the results achieved using homografts. Since these prostheses are readily available and their implantation straightforward, they are increasingly being used in patients with endocarditis. These promising results need to verified in the long term. This paper was presented at a lecture held at the 71st annual meeting of the German Society for Cardiology, Mannheim, 31. March—2. April 2005. Disclosure Form: The following study discloses my relationship with any corporate sponsor that might relate in some way to the subject presented.  相似文献   
27.
OBJECTIVE: We investigated outcomes after surgical therapy in patients with active infective endocarditis (AIE) with regard to survival in relation to surgical urgency, valve position, number of valves implanted and abscess formation. We aimed to identify independent risk factors for early mortality. METHODS AND RESULTS: Two hundred and fifty-five patients received Shelhigh bioprostheses between February 2000 and March 2007. A total of 74.1% had native and 25.9% prosthetic AIE. Surgery was regarded as urgent in 57.3% and as an emergency procedure in 38.4%. There was a highly significant difference in survival rate between patients who were operated on urgently versus in an emergency (p<0.0001), between single and double valve replacement (p=0.0206) and between patients with and without abscess formation (p=0.0245). There were two cases of early reinfection (0.78%) and six of late reinfection (2.35%) leading to re-operation. CONCLUSIONS: The survival of patients differs significantly in dependence on their surgical urgency. Better outcome could have been achieved if patients had been referred earlier for surgery and operated upon before heart failure or septic shock developed. Long-term survival was better in patients without abscess formation. The low reinfection rate of Shelhigh bioprostheses in AIE is promising and the early and mid-term results achieved need to be verified in the long-term course.  相似文献   
28.
OBJECTIVE: Due to the shortage of donor hearts, the criteria for organ acceptability have been considerably extended and donor grafts with coronary atherosclerosis are among those offered. This study evaluated whether and to what degree pre-existing coronary atherosclerosis may be acceptable. METHODS: A total of 1253 consecutive HTx recipients were investigated retrospectively for donor-transmitted coronary atherosclerosis (DCAS). Donor-transmitted coronary atherosclerosis was defined as focal atherosclerosis with stenosis of at least 50%. Inclusion criteria were absence of pre-HTx angiogram but performance of angiogram or autopsy within 6 months after heart transplantation. Kaplan-Meier analysis and log-rank test were used. RESULTS: Eighty-five out of 1253 (6.8%) cases were excluded, since coronary evaluation was not performed within 6 months (n=45) or hearts had undergone pre-transplant angiography (n=40). In 1086 patients no donor-transmitted coronary atherosclerosis was found (NDCAS group) and in 82 patients (7%) donor-transmitted coronary atherosclerosis was diagnosed by angiography (n=49) or autopsy (n=33). Single-vessel donor-transmitted coronary atherosclerosis was found in 53/82 patients (DCAS1 group) and double- or triple-vessel donor-transmitted coronary atherosclerosis in 26/82 patients (DCAS2/3 group). Three of the 82 patients with donor-transmitted coronary atherosclerosis were excluded since the autopsy report was unclear regarding degree of atherosclerosis. Early after heart transplantation the 30-day mortality in the NDCAS and DCAS1 groups was 12.2% versus 13.2% whereas in the DCAS2/3 group it was 61.5%. Beyond the first year the annual decrease with and without donor-transmitted coronary atherosclerosis (single-vessel disease) is comparable. CONCLUSIONS: Donor screening without coronary angiogram overlooks significant atherosclerotic lesions in a considerable number of cases (7.0%). Therefore, angiographic donor screening should be performed. Donor grafts with single-vessel coronary atherosclerosis may be accepted as marginal hearts; however, in our opinion, revascularisation (CABG, PTCA) should be considered. Grafts with two- or even three-vessel coronary atherosclerosis seem to have a serious risk for early graft failure. Beyond the first year the outcome of healthy grafts and grafts with donor-transmitted coronary atherosclerosis seems to be comparable.  相似文献   
29.
目的探讨鼻内镜下上颌窦(扩大)内壁切除术在鼻内翻性乳头状瘤手术中的应用价值。方法回顾分析2002年1月~2006年12月采用鼻内镜下上颌窦(扩大)内壁切除术治疗鼻内翻性乳头状瘤10例的临床资料。结果10例均在鼻内镜下完全切除。10例随访12~72个月,平均30个月;术后仅1例术后1年后复发;10例均无溢泪发生。结论鼻内镜下上颌窦(扩大)内壁切除术在鼻内翻性乳头状瘤手术中的应用是可行的,基本接近鼻侧切开的手术范围;最大优点是可避免面部瘢痕、创伤小、手术视野清晰、能够准确完整地切除肿瘤、术后复发率低。  相似文献   
30.
Three rare cases of upper eyelid trauma are presented. In high-speed traffic accidents, the upper eyelids were penetrated by glass, avulsed, and then, together with pieces of glass, pushed over the globe and buried deeply in the retrobulbar area. The invaginated eyelids were pulled out gently, the conjunctiva still attached to the globes. They were repaired primarily. In these patients eyelid function and cosmesis were preserved.  相似文献   
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