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991.
目的应用Micro-CT和骨生物力学技术,探讨骨碎补总黄酮对去卵巢大鼠的下颌骨显微结构及最大载荷的影响。方法40只3月龄雌性SD大鼠,随机分为5组:假手术组(sham operation group,Sham)、去卵巢模型组(ovariectomized group,OVX)、骨碎补总黄酮高剂量组(high-dose drynaria total flavonoids group,GB-H)、骨碎补总黄酮低剂量组(low-dose drynaria total flavonoids group,GB-L)和戊酸雌二醇组(Estradiol Valerate group,EV),建模成功后连续给药12 w。实验结束后,取下颌骨进行显微CT扫描及三维重建,然后进行最大载荷测量。结果与Sham组相比,OVX组大鼠下颌骨微结构:骨密度、相对骨体积、骨小梁厚度、骨小梁数目明显减小(P0.05),骨表面积体积比、骨小梁间隙明显增高(P0.05);下颌骨的最大载荷明显减少(P0.05)。与OVX组相比,EV组大鼠下颌骨微结构获得良好修复,最大载荷也明显修复。骨碎补总黄酮低剂量组相对骨体积、骨小梁数目较OVX组显著升高(P0.05),骨小梁间隙显著减小(P0.05)。骨碎补总黄酮高剂量组疗效优于低剂量组,大鼠下颌骨的相对骨体积、骨表面积体积比、骨小梁间隙、骨小梁数目以及下颌骨骨密度均得到一定程度修复,下颌骨最大载荷也较OVX组显著增加(P0.05)。结论骨碎补总黄酮能够修复去卵巢大鼠下颌骨微结构,提高下颌骨骨密度和最大载荷,这将可能为颌骨骨质疏松的防治提供一种新的途径。  相似文献   
992.
993.
994.

Background

The hypothesis that mucosal melanomas from different anatomic sites would have different prognostic features and survival outcome was tested in a multifactorial analysis.

Methods

Complete clinical and pathological information from 706 mucosal melanoma patients from different anatomical sites was compared for overall survival (OS) and prognostic factors.

Results

Mucosal melanomas arising from different anatomical sites did not have any significant differences in OS in a multivariate analysis (p?=?0.721). Among all 706 stage I–IV mucosal melanoma patients, depth of tumor invasion (p?<?0.001), number of lymph node metastases (p?<?0.001), and sites of distant metastases (p?<?0.001) were independent prognostic factors for OS; among 543 stage I–III patients, depth of tumor invasion (p?<?0.001) and number of lymph node metastases (p?<?0.001) were independent prognostic factors for OS; and among 547 stage IV patients, depth of tumor invasion (p?=?0.009), number of lymph node metastases (p?<?0.001), and combined distant metastases and elevation of serum lactate dehydrogenase (LDH; p?<?0.001) were independent prognostic factors for OS. The presence of c-KIT or BRAF mutations was not predictive of survival.

Conclusions

This is the first large-scale study comparing outcomes of mucosal melanomas from different anatomic sites in a multifactorial analysis. There were no significant survival differences among mucosal melanomas arising at different sites when matched for staging and prognostic and molecular factors, thus rejecting our hypothesis. We concluded that prognostic characteristics of mucosal melanomas can be staged as a single histological group, regardless of the anatomic site of the primary tumor.
  相似文献   
995.

Objective

The objective of the study is to examine the feasibility of hepatic artery resection (HAR) without subsequent reconstruction (RCS) in specified patients of Bismuth type III and IV hilar cholangiocarcinoma.

Methods

We retrospectively reviewed 63 patients who underwent hepatic artery resection for Bismuth type III and IV hilar cholangiocarcinoma. These patients were subsequently enrolled into two groups based on whether the artery reconstruction was conducted. Postoperative morbidity and mortality, and long-term survival outcome were compared between the two groups.

Results

There were 29 patients in HAR group and 34 patients in the HAR + RCS group. Patients with hepatic artery reconstruction tended to have longer operative time (545.6?±?143.1 min vs. 656.3?±?192.8 min; P?=?0.013) and smaller tumor size (3.0?±?1.1 cm vs. 2.5?±?0.9 cm; P?=?0.036). The R0 resection margin was comparable between the HAR group and HAR?+?RCS group (86.2 vs. 85.3%; P?>?0.05). Twelve patients (41.4%) with 24 complications in HAR group and 13 patients (38.2%) with 25 complications in HAR?+?RCS group were recorded (P?=?0.799). The postoperative hepatic failure rate (13.8 vs. 5.9%) and postoperative mortality rate (3.4% vs. 2.9%) were also comparable between the two groups. In the HAR group, the overall 1-, 3-, and 5-year survival rates were 72, 41, and 19%, respectively; while in the HAR?+?RCS group, the overall 1-, 3-, and 5-year survival rates were 79, 45, and 25%, respectively (P?=?0.928).

Conclusions

Hepatic artery resection without reconstruction is also a safe and feasible surgical procedure for highly selected cases of Bismuth type III and IV hilar cholangiocarcinoma.
  相似文献   
996.

Objective

The aim is to investigate whether additional resection based on intraoperative frozen section (FS) to a secondary R0(s) status are associated with different long-term survivals in pancreatic cancer patients, comparing to those with R1 or primary R0(p) status.

Methods

A systematic literature search (PubMed, Embase, Science Citation Index, Springer-Link, and Cochrane Central Register of Controlled Trials) was performed to identify all studies published up to June 2017. Survivals of patients undergoing pancreatic surgery according to the results of FS and re-resection were pooled for analysis.

Results

Five cohort studies were qualified for inclusion in this review with a total of 2980 patients. Long-term survival outcomes favored R0(p) resection as compared to R0(s) resection (HR?=?1.58, 95%CI 1.24–2.01, P?=?0.0002, I2?=?58%). No significant difference was observed for patients with or without additional resection at the time of surgery when positive FS was detected (HR?=?0.98, 95CI% 0.65–1.47, P?=?0.91, I2?=?81%).

Conclusions

The present study did not support the concept of achieving an R0 resection by intraoperative re-resection would benefit the patient’s survival. R1 margin at the time of surgery is more like a marker of aggressive tumor biology. Future well-designed randomized controlled trials are needed to confirm the conclusion.
  相似文献   
997.
998.

Background

Patients with chronic kidney disease (CKD) have worse adverse cardiovascular outcomes after coronary artery bypass grafting (CABG). However, the adverse cardiovascular outcomes between off-pump coronary artery bypass grafting (OPCAB) versus on-pump coronary artery bypass grafting (ONCAB) in these patients have been a subject of debate.

Methods

We undertook a comprehensive literature search of PubMed, Embase, and the Cochrane Library database to identify all relevant studies comparing techniques between OPCAB and ONCAB in CKD patients. We pooled the odds ratios (ORs) and hazard ratios (HRs) from individual studies and conducted heterogeneity, quality assessment, and publication bias analyses.

Results

This meta-analysis includes 17 studies with 201,889 patients. In CKD patients, OPCAB was associated with significantly lower early mortality as compared to ONCAB (OR 0.88; 95% CI 0.82–0.93; p < 0.0001). OPCAB was associated with decreased risk of atrial fibrillation (OR 0.57; 95% CI 0.34–0.97; p = 0.04), cerebrovascular accident (OR 0.46; 95% CI 0.22–0.95; p = 0.04), blood transfusion (OR 0.20; 95% CI 0.08–0.49; p = 0.0005), pneumonia, prolonged ventilation, and shorter hospital stays. No difference was found regarding long-term survival (HR 1.08; 95% CI 0.86–1.36; p = 0.51) or myocardial infarction (OR 0.65; 95% CI 0.30–1.38; p = 0.26).

Conclusions

Compared with ONCAB, OPCAB is associated with superior postoperative morbidity and the early mortality in CKD patients. Long-term survival is comparable between the two surgical revascularizations.
  相似文献   
999.
1000.

Background Context

Degenerative cervical myelopathy (DCM) is a progressive degenerative spine disease and the most common cause of spinal cord impairment in adults worldwide. Few studies have reported on regional variations in demographics, clinical presentation, disease causation, and surgical effectiveness.

Purpose

The objective of this study was to evaluate differences in demographics, causative pathology, management strategies, surgical outcomes, length of hospital stay, and complications across four geographic regions.

Study Design/Setting

This is a multicenter international prospective cohort study.

Patient Sample

This study includes a total of 757 symptomatic patients with DCM undergoing surgical decompression of the cervical spine.

Outcome Measures

The outcome measures are the Neck Disability Index (NDI), the Short Form 36 version 2 (SF-36v2), the modified Japanese Orthopaedic Association (mJOA) scale, and the Nurick grade.

Materials and Methods

The baseline characteristics, disease causation, surgical approaches, and outcomes at 12 and 24 months were compared among four regions: Europe, Asia Pacific, Latin America, and North America.

Results

Patients from Europe and North America were, on average, older than those from Latin America and Asia Pacific (p=.0055). Patients from Latin America had a significantly longer duration of symptoms than those from the other three regions (p<.0001). The most frequent causes of myelopathy were spondylosis and disc herniation. Ossification of the posterior longitudinal ligament was most prevalent in Asia Pacific (35.33%) and in Europe (31.75%), and hypertrophy of the ligamentum flavum was most prevalent in Latin America (61.25%). Surgical approaches varied by region; the majority of cases in Europe (71.43%), Asia Pacific (60.67%), and North America (59.10%) were managed anteriorly, whereas the posterior approach was more common in Latin America (66.25%). At the 24-month follow-up, patients from North America and Asia Pacific exhibited greater improvements in mJOA and Nurick scores than those from Europe and Latin America. Patients from Asia Pacific and Latin America demonstrated the most improvement on the NDI and SF-36v2 PCS. The longest duration of hospital stay was in Asia Pacific (14.16 days), and the highest rate of complications (34.9%) was reported in Europe.

Conclusions

Regional differences in demographics, causation, and surgical approaches are significant for patients with DCM. Despite these variations, surgical decompression for DCM appears effective in all regions. Observed differences in the extent of postoperative improvements among the regions should encourage the standardization of care across centers and the development of international guidelines for the management of DCM.  相似文献   
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