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71.
A study of the importance of the neutral zone in complete dentures   总被引:1,自引:0,他引:1  
Mastication, comfort, and speech were determined and compared for patients using conventional complete dentures and dentures made with the neutral zone concept.  相似文献   
72.
The authors report a patient with fulminant autoimmune hemolytic anemia due to a rare warm IgM autoagglutinin more reactive at 37 degrees C than at lower temperatures and secondary to systemic lupus erythematosis. The patient's clinical course and the serologic and immunochemical characteristics of the antibody are described, including the possibility that transfusions of small amounts of incompatible red cells may have contributed to the hemolysis. The consequences of using the initial serologic test results as the basis for therapy are discussed.  相似文献   
73.
This study comparing the relative white cell (WBC)-depleting efficiency of single and double filtration used two filters and new, sensitive, and reliable methods for performing WBC counts on WBC-depleted blood products. A single filtration of red cell (RBC) concentrates with a cotton-wool filter reduced WBC content by 98.64 percent, but the range of residual WBCs was wide, and many filtered units still contained more than the theoretical immunizing dose of 5 to 10 x 10(6) WBCs. A second filtration, however, always produced RBC units that had less than 5 x 10(6) WBCs. Although the degree of WBC depletion observed after a single filtration of a 6-unit pool of random-donor platelet concentrates was greater with a polyester filter than with the cotton-wool filter (98.92 vs. 98.14% reduction, respectively, when mean prefiltration WBC count was less than 600 x 10(6], in both cases, 25 percent of filtered products still contained greater than 5 x 10(6) WBCs; a second filtration (with the cotton-wool filter), however, produced units that were always below the immunizing dose. All double-filtered platelet concentrates had less than 10(6), and one-half had less than 10(4) residual WBCs. Platelet loss was similar with both filters (+/- 16% loss with one filtration). The effectiveness of the filters in producing products that were WBC-depleted below the immunizing dose was dependent on the prefiltration WBC content (but not on the age of the units), and it may be worthwhile to employ methods to ensure that total prefiltration WBC count of the product is less than 400 x 10(6).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
74.
Pelvic fractures are uncommon in children and account for between 0.3 and 7.5% of all pediatric injuries. Open pelvic fractures only account for up to 12.9% of all pediatric pelvic fractures. An unusual case of open complete anterior sacro-iliac joint dislocation in a 4-year-old boy is presented with a long-term follow-up. The multidisciplinary approach is reported with review of the current literature. A 4-year-old male presented to our institution in January 2012 after having been run over by a tractor. He presented with gross hemodynamical instability, MISS of 25, and an unstable lateral compression type III pelvic fracture with complete anterior dislocation of the left hemipelvis and a groin wound extending into the left thigh. The patient was managed in accordance with the ATLS and open fracture guidelines. Reduction in the dislocated SI joint was achieved via a posterior approach to the SI joint, followed by fixation with 2K wires in S1 and S2 sacral segments, with an anterior external fixator. Pelvic asymmetry post-reduction was 0.9 cm, compared to 16 cm post-injury, and asymmetry persisted till final follow-up at 5 years. At 5 years, patient regained full function, including recreational sport activities. Patients scored a 96/96 on the Majeed score (after excluding 4 points for sexual function). We believe that posterior reduction in an anteriorly dislocated SI joint in the pediatric population is a viable option. A coordinated, multidisciplinary approach and restoration of pelvic ring stability can lead to optimal outcome.  相似文献   
75.

Objective

This study aimed to comprehensively analyze the oncological long-term outcomes of trimodal therapy (TMT) and radical cystectomy (RC) for the treatment of muscle-invasive bladder cancer (BC) with or without neoadjuvant chemotherapy (NAC).

Patients and methods

A systematic search was conducted according to the PRISMA guidelines for studies reporting on outcomes after TMT and RC. A total of 57 studies including 30,293 patients were included. The 10-year overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) rates for TMT and RC were assessed.

Results

The mean 10-year OS was 30.9% for TMT and 35.1% for RC (P = 0.32). The mean 10-year DSS was 50.9% for TMT and 57.8% for RC (P = 0.26). NAC was administered before therapy to 453 (13.3%) of 3,402 patients treated with TMT and 812 (3.0%) of 27,867 patients treated with RC (P<0.001). Complete response (CR) was achieved in 1,545 (75.3%) of 2,051 evaluable patients treated with TMT. A 5-year OS, DSS, and RFS after CR were 66.9%, 78.3%, and 52.5%, respectively. Downstaging after transurethral bladder tumor resection or NAC to stage ≤pT1 at RC was reported in 2,416 (29.1%) of 8,311 patients. NAC significantly increased the rate of pT0 from 20.2% to 34.3% (P = 0.007) in cT2 and from 3.8% to 23.9% (P<0.001) in cT3–4. A 5-year OS, DSS, and RFS in downstaged patients (≤pT1) at RC were 75.7%, 88.3%, and 75.8%, respectively.

Conclusion

In this analysis, the survival outcomes of patients after TMT and RC for MIBC were comparable. Patients who experienced downstaging after NAC and RC exhibited improved survival compared to patients treated with RC only. Best survival outcomes after TMT are associated with CR to this approach.  相似文献   
76.
BACKGROUND: Several substitutes for intact, viable platelets have been used for transfusion, both to people and in animal models, with varied success. Infusible platelet membrane (IPM) is prepared from human platelets. IPM retains the glycoprotein (GP)lb receptor and has platelet factor 3 activity (procoagulant activity). However, factor V, serotonin, a cytoplasmic marker enzyme (purine nucleotide phosphorylase), GPIIb/IIIa complex, and HLA class I and II antigens are all absent in IPM. STUDY DESIGN AND METHODS: IPM is prepared from outdated platelets. The platelets were disrupted by freezing and thawing; they were washed and heated to inactivate possible viral contaminants, and then the sonicated membrane microvesicle fraction was separated and lyophilized. The hemostatic activity of IPM was measured by its ability to reduce the prolonged bleeding time in thrombocytopenic rabbits. RESULTS: Administration of IPM at a dose of 2 mg per kg results in a substantial reduction in the bleeding time. In a series of 23 experiments, a median preinjection bleeding time of 15 minutes was reduced to 6 minutes within 4 hours after IPM administration. Administration of IPM did show a mild enhancement in the thrombogenicity index, as measured in the Wessler rabbit model. This enhancement is, however, not significant, as a thrombogenicity index value of up to 0.6 is clinically acceptable. CONCLUSION: IPM may have clinical potential as a substitute for platelets in the treatment of bleeding due to thrombocytopenia.  相似文献   
77.
目的:为保护濒死心肌提供机会窗口,对比观察经冠脉移植自体骨髓单个核细胞或间充质干细胞后,实验性急性心肌梗死动物心功能变化及心肌组织核转录因子кB、心肌细胞凋亡情况。方法:实验于2005-03/2006-11在河北省人民医院实验中心完成。选用24只雄性冀中白猪,随机数字表法分为4组:正常对照组、模型组、单个核细胞组、间充质干细胞组,6只/组。①24只猪均以盐酸氯胺酮200mg臀部肌肉注射麻醉后,分别于各自右侧股骨抽取骨髓20mL,采用Fercoll法分离获得骨髓单个核细胞,加入胶体金溶液,培养12~16h待用。分离过程中取出含有骨髓单个核细胞成分的细胞层,常规培养传代,每3d换液1次,贴壁生长细胞即为骨髓间充质干细胞,加入胶体金溶液,培养24h待用。②除正常对照组外,其余各组均经导管球囊封闭第一对角支以远的前降支,复制猪急性心肌梗死模型。单个核细胞组、间充质干细胞组均于造模后立即开通前降支,分别经球囊注入预先分离的骨髓单个核细胞6×108个、间充质干细胞6×108个。模型组造模后于梗死1h开通前降支,经球囊注入磷酸盐缓冲液10mL。③各组分别于术前及术后4周经心脏超声检测心功能,取材行病理学检查、心肌组织核转录因子кB的免疫组织化学检测及心肌细胞凋亡检测。结果:24只雄性白猪均进入结果分析。①心功能变化:术前各组左心室收缩末内径、左心室舒张末内径、左心室射血分数、短轴缩短率基本相似。移植术后4周,正常对照组、单个核细胞组、间充质干细胞组左心室舒张末内径均明显低于模型组(F=4.68,P=0.01),左心室射血分数及短轴缩短率均明显高于模型组(F=5.14,P=0.01;F=3.32,P=0.04),各组左心室收缩末内径差异无显著性意义(F=1.64,P=0.21)。②心肌组织病理学改变:电镜下单个核细胞组、间充质干细胞组在梗死边缘区可见有胶体金颗粒的不成熟的心肌细胞,胞质中散在肌丝结构,肌丝排列紊乱不规则。③心肌组织核转录因子кB阳性率表达:与模型组比较,单个核细胞组、间充质干细胞组的梗死边缘区核转录因子кB阳性率明显降低(F=25.59,P=0.0001);正常心肌区核转录因子кB阳性率亦明显降低(F=18.20,P=0.0001)。④心肌细胞凋亡检测结果:与模型组比较,单个核细胞组、间充质干细胞组在心肌梗死区细胞凋亡率均明显降低(F=6.63,P=0.0027),梗死边缘区细胞凋亡率亦明显降低(F=36.07,P=0.0001)。正常心肌区单个核细胞组细胞凋亡率与模型组基本相似(F=9.69,P=0.004),但间充质干细胞组有所降低。⑤心功能与心肌细胞凋亡及心肌组织NF-кB的相关性:急性心肌梗死4周时,左心室射血分数与心肌细胞凋亡、心肌组织核转录因子кB均呈负相关(r=0.613,P=0.001;r=-0.437,P=0.033)。心肌细胞凋亡与心肌组织核转录因子кB呈正相关(r=0.672,P=0.002)。结论:经冠脉移植骨髓单个核细胞和间充质干细胞均可改善实验性急性心肌梗死动物的心功能,与梗死边缘区核转录因子кB表达降低及心肌细胞凋亡减少有关。骨髓单个核细胞移植的促血管增生作用优于间充质干细胞移植。  相似文献   
78.
Application of biosafety principles in blood establishments   总被引:1,自引:0,他引:1  
In light of increasing public and employee concern over potential infectious hazards associated with blood and other body fluids, several government agencies (the Food and Drug Administration, the Centers for Disease Control, the Occupational Safety and Health Administration, the Environmental Protection Agency, the Health Care Financing Administration and the National Heart, Lung and Blood Institute) cosponsored a Biosafety Workshop in April 1988. The objective of the workshop was to identify appropriate biosafety practices and standard control procedures to protect workers involved in the collection, storage, and transportation of human blood donations with the least possible disruption of the nation's blood supply. Speakers focused on human immunodeficiency virus (HIV) and hepatitis B virus (HBV); however, the safety principles discussed were considered equally applicable to other known (e.g., non-A, non-B hepatitis and human T-lymphotropic virus type I (HTLV-1) blood-transmitted infections. The resulting consensus included the need for blood establishments to develop and apply thoughtful biosafety programs to address staff training, accident prevention, HBV vaccination, handling spills, managing contaminated waste and transporting blood specimens. There was lack of agreement, however, on the usefulness of gloves during the phlebotomy of healthy blood donors.  相似文献   
79.
A case of symmetrical, diffuse macrocheilia due to lymphangiectasia is presented. No primary cause for this case or for many other pathologic forms of macrocheilia has been established. Tranverse mucosal wedge resection of the lip with mucosal advancement, however, is a satisfactory method of treatment.  相似文献   
80.
Ventricular tachycardia associated with prior myocardial infarction account for significant morbidity, mortality, and health care costs despite the favorable outcomes shown by ICD clinical trials. Catheter ablation has been increasingly used as an adjunctive therapy in the management of scar-related ventricular tachycardia. Novel technologies have facilitated the outcomes of current ablation strategies. Three-dimensional mapping systems have allowed identification of the scar substrate, its critical sites in the tachycardia circuit, and selection of ablation sites based on fairly precise electroanatomic substrate.  相似文献   
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