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91.
The purpose of this prospective randomized study was to investigate the manifestations and efficiency of mandibular block (MB) using a standardized method. In this study, 123 patients requiring MB were randomly assigned to receive MB using a repeated measures design. Mandibular block was administered in each patient by using 2.1 mL of 2% lidocaine with 1:100 000 epinephrine for the inferior alveolar nerve, lingual nerve, and/or buccal nerve. Clinical parameters including the electric pulp test and test for soft tissue sensation using a sharp dental explorer were assessed on both the operated side and contralateral side before and 5, 10, and 15 minutes after injection, and at the end of surgical procedure. Results of the test of the contralateral tooth served as the control group. No response to the electric pulp test at a maximum output (80 readings) was used as the criterion for pulpal anesthesia. Results obtained with electric pulp test and sharp explorer test were not significantly different during various intervals on the contralateral side, indicating the reliability of this standardized method for assessing MB. The MB technique achieved a high rate of subjective numbness (100%) according to the perception of the patients of overall numbness and lip numbness. Overall anesthetic success rates of pulpal anesthesia were 5.7% for the central incisor, 38.2% for the canine, 55.3% for the first premolar, and 90.2% for the first molar. No significant difference was found in the efficiency of anesthesia related to sex or age of the patients. A slower onset of pulpal anesthesia after MB was found for the anterior teeth than for the posterior teeth. This study suggests that the use of a standardized method might produce a clearer and more comprehensive evaluation of the efficiency and manifestations of MB.  相似文献   
92.
医药企业对电子商务营销模式的科学选择   总被引:1,自引:0,他引:1  
根据电子商务在我国快速发展的形势,分析我国医药企业可选择的电子商务应用模式,研究企业进行模式选择时所需要考虑的因素,提醒医药企业选择电子商务模式时应依据自身特点积极稳妥地决策,切忌盲目一哄而上。  相似文献   
93.
Ruptured aneurysms of the distal anterior choroidal artery (AchA) are extremely rare and management is dictated by clinical presentation. This report describes a rare patient with a distal AchA aneurysm and subarachnoid and intraventricular haemorrhage. A 60-year-old woman presented with a sudden onset of severe headache and vomiting. No aneurysms could be found on initial angiograms. A repeat angiogram performed 10 days after admission demonstrated an aneurysm in a branch of the cisternal segment of the left AchA without a definite neck. Surrounding vessels showed multifocal stricture and dilatation. Microsurgical clipping was not performed because the patient died suddenly due to pulmonary failure. The aetiology of the aneurysm in this case and surgical strategy are discussed.  相似文献   
94.
Background/purpose: Vitiligo and nevus depigmentosus (ND) present similar hypopigmented macules with significantly different prognoses. Although the distinction between the two diseases is important, differential diagnosis relies on medical history and physical examination, which is far from decisive in some cases. The Mexameter® is an objective skin color-measuring device, and has been reported to provide a reproducible and sensitive means of quantifying small skin color differences. In this study, we investigated the usefulness of a Mexameter® for discriminating these diseases.
Methods: A selection of 202 hypopigmented skin lesions (182 from vitiligo and 20 from ND) were the objects of this study. Using a Mexameter, MIs were obtained from lesions and symmetrically located control skin. RMIs, ratios of the MIs of lesional skins to control skins, were calculated.
Results: The mean MIs and RMIs were significantly different for vitiligo and ND. The mean RMI of ND lesions was 74±13, which was significantly higher than that of vitiligo lesions (50±24). No ND lesion had an RMI of <50%.
Conclusion: This study shows that the Mexameter®, an objective pigment-measuring device, can be used to achieve a more accurate diagnosis of hypopigmentary disorders, and that the relative melanin index (RMI), which represents the relative pigment levels, might be a more effective parameter than the melanin index (MI) itself for comparing pigmentation differences.  相似文献   
95.
室上性心动过速导管消融治疗的新认识   总被引:1,自引:0,他引:1  
导管消融治疗室上性心动过速(室上速)由于有95%以上的成功率及极低的并发症,成为目前治疗室上速的一线方法。随着心电生理学的进展,室上速电生理机制及治疗方法仍在不断改善。这些新的标测技术和消融方法的进步又进一步提高了治疗手术的成功率。现将近些年室上速消融治疗的一些新认识简述如下。1房室结折返性心动过速(AVNRT)的导管消融治疗房室结折返性心动过速是最常见的室上速之一。传统的理论认为房室结内存在快、慢2个径路,AVNRT时折返环局限在房室结内。这一理论的最有力的支持证据是在AVNRT时心房的激动可以与心动过速分离,由此…  相似文献   
96.
瘀祛补肾法治疗前列腺增生症46例   总被引:2,自引:0,他引:2  
我院在1998年6月~2004年6月采用瘀祛补肾法治疗前列腺增生症46例,现总结如下.  相似文献   
97.
目的探讨衰老对大鼠阴茎组织结构、NO(nitric oxide)-cGMP(cvclic Guanosine Monophosphate)通路及端粒酶活性的影响作用。方法本课题以不同月龄大鼠阴茎组织及培养的平滑肌细胞为研究对象,检测不同月龄大鼠阴茎组织中NO量、NOS(Nitric Oxide Synthase)活性、cGMP量、端粒酶活性及海绵体结构的变化,并比较大鼠、人阴茎组织及大鼠原代海绵体平滑肌细胞的端粒酶活性。结果(1)大鼠阴茎组织中NO量、NOS活性均先升高后降低,各月龄组间有显著差异。阴茎组织cGMP含量逐渐降低,各月龄组间差别显著;(2)随龄增加,平滑肌纤维逐渐减少,胶原纤维增多,粗大成团,窦状隙变少、变窄:(3)大鼠阴茎组织端粒酶活性以2月龄活性最高,随龄增加逐渐下降。人阴茎组织中无端粒酶活性。结论(1)衰老对大鼠阴茎组织结构、NO.cGMP通路及端粒酶活性有显著影响,提示衰老与ED关系密切;(2)大鼠阴茎组织有端粒酶活性,可作为研究细胞衰老与ED关系有关端粒酶的模型。  相似文献   
98.
99.
Hirschsprung disease (HSCR) is a congenital disorder characterized by an absence of ganglion cells in the nerve plexuses of the lower digestive tract. Although mutations in eight different genes (EDNRB, EDN3, ECE1, SOX10, RET, GDNF, NTN, SIP1) have been identified in affected individuals, it is now clear that RET and EDNRB are the primary genes implicated in the etiology of HSCR. All eight genes are involved in the early development of the enteric nervous system, and most act through two distinct biochemical pathways mediated by RET and EDNRB. Mutations in RET and EDNRB account for up to 50% and 5% of HSCR cases in the general population, respectively. Interaction between these two signaling pathways could modify RET expression and, therefore, HSCR phenotype. Here, we report the case of a 1-year-old Taiwanese boy who presented with abdominal distension since birth and bilious vomiting after feeding. HSCR (short-segment type) was diagnosed based on X-ray, lower gastrointestinal series and biopsy findings. Mutation analysis revealed a heterozygous T>C missense mutation in exon 1 of the EDNRB gene, that substitutes the highly conserved cysteine-90 residue in the extracellular domain of the G protein-coupled receptor with an arginine residue (C90R). No RET gene mutation was detected in this patient.  相似文献   
100.
Mandibular prognathism (MP) or skeletal Class III malocclusion with a prognathic mandible is one of the most severe maxillofacial deformities. Facial growth modification can be an effective method of resolving skeletal Class III jaw discrepancies in growing children with dentofacial orthopedic appliances including the chincup, face mask, maxillary protraction combined with chincup traction and the Fr?nkel functional regulator III appliance. Orthognathic surgery in conjunction with orthodontic treatment is required for the correction of adult MP. The two most commonly applied surgical procedures to correct MP are sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy. Both procedures are suitable for patients in whom a desirable occlusal relationship can be obtained with a setback of the mandible, and each has its own advantages and disadvantages. In bilateral SSRO, the intentional ostectomy of the posterior part of the distal segment can offer long-term positioned stability. This may be attributable to reduction of tension in the pterygomasseteric sling that applies force in the posterior mandible. While various environmental factors have been found to contribute to the development of MP, heredity plays a substantial role. The relative contributions of genetic and environmental components in the etiology of MP are unclear. The recent identification of the genetic susceptibilities to MP constitutes the first step toward understanding the molecular pathogenesis of MP. Further studies in molecular biology are needed to identify the gene-environment interactions associated with the phenotypic diversity of MP and the heterogenic developmental mechanisms thought to be responsible for them.  相似文献   
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