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51.
Through immunohistochemical technique, distribution of FN in normal mucosa, benign and malignant tumors of human gastrointestinal tract were studied. In normal and adenoma tissues, FN was found in both basement membrane (BN) and interstitial tissue. While in cancer tissue, there was a consistent decrease of BM FN content around the tumor nests particularly more apparently in cases of invading carcinoma. Statistical analysis showed that the reduction of BM FN was correlated with the degree of tumor dedifferentiation but not with the incidence of regional metastases. No association was noticed between the stroma FN and tumor behaviors. Since small blood vessels were usually delineated clearly by the staining for FN, FN might be considered as a marker in identifying the invasion of blood vessel wall by tumor cells. It is suggested that lack of BM FN in tumor tissues might be mainly due to decrease of FN synthesis by the tumor cells.  相似文献   
52.
本文讨论了常规设计的游离端义齿存在的问题,并对Kratochvil提出的RPI卡环,结合力学知识,提出了RPI卡环在游离端义齿应用中的优缺点,并通过典型病例介绍和对20名病例随访分析表明,用RPI卡环修复游离端牙齿缺失,可获得较好的临床效果。  相似文献   
53.
本文分析经皮球囊二尖瓣成形术治疗风湿性二尖瓣狭窄的疗效。结果表明 ,PBMV耗费少 ,住院期短。效果良好 ,值得推广应用  相似文献   
54.
目的 :检测周围神经损伤后免疫系统的变化。方法 :用 MTT法检测了坐骨神经损伤 1 ,2 ,5,7和 1 4d的大鼠脾细胞 NK活性及淋巴细胞转化功能 ,并用 PEG沉淀法检测了大鼠血清中循环免疫复合物 (CIC)的含量。结果 :坐骨神经损伤后 7和 1 4d大鼠脾细胞的自发转化率较对照组 (同样手术应激但无坐骨神经损伤 )略有增高 ;循环免疫复合物的含量术后 7d明显增高 ,1 4d时增加明显 ;而 NK活性则无明显变化 ,后期变化如何尚待进一步研究。结论 :周围神经损伤后 ,机体发生了免疫变化。  相似文献   
55.
三个半规管阻塞动物模型的建立   总被引:5,自引:0,他引:5  
目的 旨在建立豚鼠单侧三个半规管阻塞的动物模型。方法 利用20只豚鼠行单侧三个半规管阻塞,观察手术前后眼震电图、听性脑干反应(auditory brainstem responses,ABR)、畸变产物耳声发射(distortion product otoacoustic emission,DPOAE)及形态学的变化,非手术耳作对照。结果 豚鼠术后1d出现自发性眼震,正弦摆动刺激单侧眼震反应消失,  相似文献   
56.
Objective To assess clinical outcomes of children seen in consultation for peritonsillar abscess treated without the routine use of computed tomography or needle aspiration. Study Design Retrospective review of patients evaluated in the emergency department for possible peritonsillar abscess. Patient outcomes are reviewed with a statistical analysis of children grouped according to age. Methods A series of 102 patients, ages 8 months to 19 years, who were evaluated by the emergency department with otolaryngology consultation for possible peritonsillar abscess. All patients were admitted and given intravenous fluid replacement, antibiotics, and analgesia. Patients who responded to 24 hours of medical treatment were discharged, whereas patients who did not respond underwent elective tonsillectomy. Main Outcome Measure Outcome of patients evaluated for peritonsillar abscess treated without immediate surgery, needle aspiration, or computed tomography. Outcomes are correlated with age and clinical findings. Results Fifty‐two patients were discharged after initial medical therapy. Fifty patients underwent elective tonsillectomy; 40 of these patients were found to have abscesses at the time of surgery. When analyzed according to age, patients ages 8 months to 6 years were more likely to respond to medical treatment than children ages 7 to 12 and 12 to 19 (P = .023). Significant differences in the mean age of children requiring surgery (11.0 y) compared with those who responded to medical treatment (7.9 y) were observed (P = .003). Younger children who underwent tonsillectomy had a lower incidence of surgically confirmed abscess. Conclusions A significant number of children presenting with odynophagia, malaise, pharyngotonsillar bulge, and decreased oral intake respond to medical therapy without radiological evaluation or surgical intervention. Additionally, younger children (1–6 y) are more likely to respond to medical treatment than older children. Pertinent clinical data, as well as advantages and disadvantages of this approach, are discussed.  相似文献   
57.
后半规管阻塞前后豚鼠前庭及耳蜗功能的动态变化   总被引:6,自引:1,他引:5  
目的 探讨机械性后半规管阻塞前后豚鼠前庭和耳蜗功能的动态变化。方法 采用20只豚鼠建立单侧后半规管阻塞的动物模型,观察手术前后眼震电图,听性脑干反应,耳声发射等变化。结果 术后第1天,第3天豚鼠正弦摆动刺激术侧眼震反应,明显减术,术后第5天起双侧眼震恢复正常。术后早期ABR阈值一度升高,第5天达高峰,ABR阈值平均升高4.5dB。DPOAE反应幅度无明显改变。结论 后半规管阻塞能选择性地消除后半规  相似文献   
58.
目的:探讨切除侧颅底肿瘤的最佳入路.方法:44例患者中,采用下颌外旋入路17例,耳后C形切口入路16例,上颌外旋入路7例,颞额入路4例.结果:25例良性肿瘤术后无复发;19例恶性肿瘤中,术后生存不足1年2例,1年以上4例,2年以上7例,3年以上6例.结论:下颌外旋入路适用于切除咽旁间隙、颞下窝、鼻咽部、口咽部、蝶骨、斜坡及上颈椎肿瘤;耳后C形切口入路适用于切除颞骨肿瘤.  相似文献   
59.
Compared with the nucleic acid amplification test (NATT), the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapid antigen self-testing (RAST) has advantages in speed and convenience. However, little is known about people's acceptance and influencing factors for SARS-CoV-2 RAST. A cross-sectional study was conducted from April 21 to 30, 2022 in China. The χ2 test and multivariate logistic regressions were used to identify the influencing factors. The structural equation model was used to test the extended protective motivation theory (PMT) model hypotheses. Among the total of 5107 participants, 62.5% were willing to accept the SARS-CoV-2 RAST. There were significant differences in acceptance among different residences (p < 0.001), educational level (p < 0.001), occupation (p < 0.001), monthly income (p < 0.001), travel frequency (p < 0.05), and feelings about NATT (p < 0.001). Response efficacy (β = 0.05; p = 0.025) and self-efficacy (β = 0.84; p < 0.001) had a positive effect, while response cost showed a negative effect (β = −0.07; p < 0.001). The public's major concerns about SARS-CoV-2 RAST are its reliability, testing method, price, and authority. Overall, a moderate intention to use SARS-CoV-2 RAST was found among the Chinese population. The extended PMT can be used for the prediction of intention to accept the RAST. We need to take measures to increase people's acceptance of SARS-CoV-2 RAST.  相似文献   
60.
研究脑缺血再灌注期间海马CA1区锥体细胞微管运动蛋白活性的变化。方法沙土鼠前脑缺血再灌注,脑缺血10min。将20只土鼠随机分为4组:假手术组、再灌注Ⅰ组(再灌注6h)、再灌注Ⅱ组(再灌注48h)、再灌注Ⅲ组(再灌注96h)。采用免疫组织化学方法结合计算机图像分析测定脑缺血再灌注期间海马神经元微管运动蛋白活性。结果脑缺血再灌注期海马CA1区微管运动蛋白活性明显下降,在再灌注6h,48h,96h时期  相似文献   
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