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41.
42.

Antibiotics, which can be used as veterinary drugs, are widely used in the prevention and treatment of infectious diseases for animals. However, overuse of antibiotics had caused serious problems on food contamination and human harm. For control such public issues, several of techniques have been in recent years. Ratiometric fluorescent (RF) technique, as one of the most promising strategies for quantitatively evaluated analytes, had been extensively developed for the readily measurements on the two different fluorescent emission intensities. In this review, the construction strategies for recent RF sensors will be mainly focused on. Meanwhile, the recent advances and new tendencies for detection of antibiotics based on RF technique shall be introduced. Finally, outlooks on the opportunities and challenges for quantitative fluorescence sensing on antibiotics will be summarized.

  相似文献   
43.
藜草花粉过敏与支气管哮喘的研究   总被引:1,自引:0,他引:1  
为了确定藜草花粉过敏原对哮喘患者的致敏作用。对外源性哮喘患者用藜草花粉过敏原进行了皮肤挑刺试验(SPT)和支气管激发试验(BPT)。结果藜草花粉SPT阳性者为28.2%,18例BPT阳性者中,14例出现哮鸣音。藜草花粉BPT与SPT的符合率为85%。提示藜草花粉过敏原是我国哮喘患者的一个重要吸入性过敏原。  相似文献   
44.
左上腹腹膜腔的矢状断面解剖学研究   总被引:1,自引:1,他引:1  
刘树伟  王永贵 《解剖学报》1996,27(2):118-122
  相似文献   
45.
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   
46.
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   
47.
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   
48.
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   
49.
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   
50.
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   
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