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1.
生物安全柜是重要的一级屏障设备,适当的控制方式对生物安全柜的防护能力是很重要的。文中主要介绍了生物安全柜的控制要点和几种控制方式及其特点。  相似文献   
2.
内镜辅助方型脸改型术   总被引:4,自引:0,他引:4  
目的探讨内镜在方型脸改型术中的临床应用效果。方法采用口内入路,在内镜辅助下,用高速涡轮气钻截除肥大下颌角、切除部分咬肌和颊脂垫,进行方型脸的面部改型。结果本组共38例,其中男3例,女35例,年龄21~40岁。内镜完全可以清楚显示下颌升支、下颌角、下颌体下缘,视野清晰。使用高速涡轮气钻截除肥大下颌角可以更加精确和容易,且创伤小,出血少,手术时间短,感染风险低。下面部轮廓改善满意。结论内镜辅助方型脸改型术,有助于获得良好的手术效果。  相似文献   
3.
咬肌与颅面形态的关系   总被引:3,自引:0,他引:3  
目的探讨咬肌与颅面形态之间的关系,了解咬肌体积与邻近骨骼结构的大小及形态的相关性。方法对40例要求改变脸型者进行磁共振成像(MRI)测量,人体测量,头部正位、侧位和下颌骨曲面断层X线检查,测量并计算咬肌体积(MsV),测量头长(HL)、头宽(HB)、面长(FL)、面宽(FB)、下颌角间宽(IB)、下颌骨体长(CL)、下颌角切线长(MAL)、下颌角角度(JA),计算颜面形态指数FI(FL/FB)、头颅指数C(IHB/HL)。用SPSS11.5软件统计分析MsV与HI。HB、FL、FB、IB、CL、MAL、JA、FI、CI之间的相关性。结果MsV与JA呈明显负相关,与CL、MAL、IB、FB、HL呈明显正相关,与CL、FI、HB无明显相关性。结论咬肌肥大可能是方脸面型的成因之一,是影响面型的重要因素。  相似文献   
4.
Summary: It is not generally appreciated that intractable seizures involving the face area are amenable to surgical treatment. Twenty patients with onset of sensorimotor seizures in the face area of the pre- and postcentral gyri have been studied and surgically treated since 1948. Seizures started in the face, tongue, or throat, followed by diverse patterns depending on spread of seizure activity. Two patients had epilepsia partialis continua; 6 had either tonic or atonic drop attacks. All patients had pre- and postcentral face area resections, 12 in the dominant hemisphere. In addition, 3 had more extensive postcentral removal, 7 had temporal lobe, and 4 had small separate or contiguous frontal or parietal resection. Because the seizures were not sufficiently reduced by the first operation, 6 required reoperation; 4 of these patients had residual epileptiform activity on electrocorticogram (ECoG) after the first resection. Three patients had new neurologic signs that did not return to the preoperative level, but in 2 of them the deficit related mainly to higher resection in the central area. All but 2 of these 20 patients had at least moderate seizure reduction. Corticectomy can be performed for treatment of seizures arising in the lower central area and usually does not lead to significant permanent neurologic deficit.  相似文献   
5.
Latex allergy in infants younger than 1 year   总被引:2,自引:0,他引:2  
BACKGROUND: The prevalence of latex allergy in children is increasing worldwide. Previous multiple operations or atopic predisposition are known risk factors. In contrast, only sporadic cases of latex allergy have been reported in infants younger than 1 year, and the causative latex-containing products or symptoms in young infants have not been studied in detail. OBJECTIVE: The purpose of this study is to analyse the symptoms and risk factors of latex allergy in young infants. METHODS: Cases of latex allergy in infants younger than 1 year were studied in detail. Clinical course, causative latex-containing products were spotted and detailed analysis for latex allergy in patients and patients' parents was performed. CONCLUSION: We report nine cases of latex allergy in infants younger than 1 year. None of them have any abnormality or previous operations. Six patients had atopic eczema/dermatitis syndrome, one patient had bronchial asthma, whereas two patients had no overt allergic diseases. Symptoms of latex allergy were wheezing, swelling of face or lips, facial rash, or anaphylaxis, and causative latex-containing products were teat, pacifier, nose cleaner, teether, balloon, or enema tube. All of the nine patients had positive skin prick test to latex and extract from causative latex-containing products, whereas eight patients had positive serum latex-specific IgE. Study for family history revealed that latex allergy was noted in either father or mother in six patients, in both father and mother in one patient, whereas no latex allergy was noted in parents in two patients. It should be noted that all of these patients had latex-induced symptoms at home. Latex allergy in young infants may not be unusual. Physicians should be aware of latex allergy, and care should be taken to avoid contact with latex in young infants, especially when there is family history for latex allergy.  相似文献   
6.
短发卡RNA对人胃癌细胞STAT3基因的沉默作用   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:探讨STAT3基因小发夹RNA(shRNA)表达质粒对胃癌MKN-45细胞STAT3基因的干扰作用。方法:根据STAT3 mRNA 编码序列,设计RNA干扰靶点,构建STAT3基因的特异性小RNA干扰质粒(psiRNA-H1/STAT3),使用脂质体转染人胃癌细胞系(MKN-45细胞)。实验分为对照(A)组,psiRNA-H1转染(B)组和psiRNA-H1/STAT3转染(C)组。通过RT-PCR和Western Blot检测STAT3特异性小RNA干扰基因对胃癌细胞STAT3基因mRNA和蛋白表达的影响。结果:psiRNA-H1/STAT3经限制性酶切及部分序列分析证明基因插入正确,并经测序证实。将其成功转染MKN-45细胞后,该细胞的STAT3 mRNA和蛋白表达均明显下降(P<0.05)。 结论:将成功构建的针对STAT3基因的shRNA表达载体转染MKN-45细胞,能有效抑制该细胞的STAT3 mRNA和蛋白表达,为STAT3基因靶向治疗提供一定的实验依据。  相似文献   
7.
Three-dimensional recording of the surface of the human body or of certain anatomical areas has gained an ever increasing importance in recent years. When recording living surfaces, such as the human face, not only has a varying degree of surface complexity to be accounted for, but also a variety of other factors, such as motion artefacts. It is of importance to establish standards for the recording procedure, which will optimise results and allow for better comparison and validation. In the study presented here, the faces of five male test persons were scanned in different experimental settings using non-contact 3D digitisers, type Minolta Vivid 910). Among others, the influence of the number of scanners used, the angle of recording, the head position of the test person, the impact of the examiner and of examination time on accuracy and precision of the virtual face models generated from the scanner data with specialised software were investigated. Computed data derived from the virtual models were compared to corresponding reference measurements carried out manually between defined landmarks on the test persons' faces. We describe experimental conditions that were of benefit in optimising the quality of scanner recording and the reliability of three-dimensional surface imaging. However, almost 50% of distances between landmarks derived from the virtual models deviated more than 2mm from the reference of manual measurements on the volunteers' faces.  相似文献   
8.
9.
A few hours after servicing illuminated lamps inside a whole body ultraviolet radiation B (UVB) phototherapy cabin, a technician developed erythema to the anterior neck with subsequent peeling, despite wearing a UV-opaque face shield. Measurements using polysulphone film badges attached to various sites on the head and neck of a mannikin were carried out to explore the spatial distribution of UVB exposure. It was found that the lower face and neck can receive sufficient exposure to result in erythema, the reason being that the fluorescent lamps will extend to about 1.5 m inferior to the head of an upright person and so result in irradiation from below. It is important, therefore, that if operators or service personnel need to be in an illuminated UVB cabin for several minutes or more, adequate protection should be provided to the chin and neck, in addition to a UV-opaque face shield.  相似文献   
10.
We report on a female baby with Fryns syndrome who died soon after birth. The patient had short limbs, coarse face, hypoplastic lungs, diaphragmatic hernia, and acral hypoplasia. Literature review disclosed varying degrees of skeletal manifestations in Fryns syndrome; short limbs may be a component of Fryns syndrome. © 1995 Wiley-Liss, Inc.  相似文献   
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