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121.
计算机技术在中药现代化进程中的作用   总被引:5,自引:1,他引:5  
中药研究手段的现代化是中药现代化最重要的组成部分。现代多学科的不断相互交叉渗透,特别是本世纪出现的计算机技术和近年发展的各种多媒体技术等,给建立新的研究方法和手段带来了良好的机遇。利用计算机自动控制和图像分析处理技术结合摄影、跟踪扫描、显微成像等先进手段,从动物的整体行为到细胞水平进行药理实验的实时监测处理和图像分析正成为国际药学界的主导方向。各种HPLC、核磁共振仪等化学分析分离技术已广泛采用了计算机技术。近年来发展的计算机药物辅助设计系统、学习记忆、自主活动等行为学计算机监控系统也开始用于药学…  相似文献   
122.
Rationale: Drug abuse is serious and costly health problems. Present understanding that drug addiction is a chronic brain disease paves the way for pharmacotherapy. Unfortunately, few medications have proven effective for the treatment of addiction and dependence. Searching novel strategies of pharmacotherapy against drug addiction are challenging. Agmatine ( decarboxylated L - arginine), an endogenous imidazoline receptor ligand, with multiple pharmacological profiles including its NMDA antagonistic properties, attracts the attention for its potential therapeutic efficacy for drug addiction.  相似文献   
123.
1网络与现代生活:对焦虑、不安的宣泄 焦虑和不安正普遍地袭扰着现代人.不论是在校的学生还是社会其它领域的人们都不同程度地感受到来自生存竞争、环境恶化、疾病滋生和由失望、落败、不满等心理情绪无从排解而带来的对外界的不安全感和对人生意义的空缺感.  相似文献   
124.
This human study was conducted to evaluate the effect of chronic alcohol consumption on plasma concentrations of lipid and the antioxidative system in 44 Korean alcoholics and 45 age-, sex-, and nationality-matched nonalcoholic subjects. Plasma triacylglycerols and atherogenic index were higher in alcoholics than in control subjects. Plasma total cholesterol was not different among groups, but plasma high-density lipoprotein cholesterol was lower in alcoholics. There were positive correlations between ethanol consumption and plasma lipid peroxide and atherogenic index in all subjects; there were negative correlations between ethanol consumption and plasma high-density lipoprotein cholesterol in all subjects. There were no significant differences between alcoholics and control subjects in plasma concentrations of α-tocopherol, although plasma α-tocopherol/lipid tended to be lower in alcoholics. Plasma retinol was lower in alcoholics. These results suggest that chronic ethanol consumption can contribute to increased risk for vascular diseases in Korean alcoholics.  相似文献   
125.
BACKGROUND: Septic cavernous sinus thrombosis (CST) is a rare and fatal disease. Clinical presentations in the early stage are nonspecific, and the sensitivity of cranial axial computed tomography (CT) with thick section is low. This study analyzed the clinical manifestation and neuroimaging findings in patients with septic CST in a medical center in Taiwan. METHODS: This retrospective case series included nine patients with septic CST who had typical symptoms and clinical course, evidence of infection, and imaging studies which demonstrated cavernous sinus lesion, and who were treated between 1995 and 2003 at National Taiwan University Hospital. RESULTS: Seven (77.8 %) patients were more than 50 years old. Five (55.6%) had diabetes, and three (33.3%) had hematologic diseases. All cases were associated with paranasal sinusitis. The most frequent initial symptom was headache (66.7%), followed by ophthalmic complaints (diplopia or ophthalmoplegia, 55.6%; blurred vision or blindness, 55.6%), and ptosis (44.4%). Initial cranial images failed to identify CTS in all patients. Subsequent magnetic resonance imaging (MRI) or coronal contrast-enhanced CT (CECT) with thin section confirmed the diagnosis. Fungi were the most common pathogens (55.6%). The inhospital case-fatality rate was high (44.4%). CONCLUSION: Due to the high case-fatality rate and low yield rate of blood cultures, fungal CST should be suspected in an immunocompromised patient with ophthalmic complaints that progress from one eye to the other. Coronal thin-section CECT may be a useful alternative to MRI as a diagnostic modality for this condition.  相似文献   
126.
Purpose: To investigate the relationships between the axonal sprouting and target neurotization by central neurons after nerve heterocon-nection. Methods: Unilateral (right) vagal-hypoglossal nerve anastomosis (VHA) was performed in adult cats. Following 3-315 days postoperation (dpo), quantitative analyses and ultrastructural changes in the proximal portion of the vagal-hypoglossal heteroconnected nerve as well as the time course of neuronal regeneration were studied. Along with this, horseradish peroxidase (HRP) retrograde tracing technique was used to label the neurons of dorsal motor vagal nucleus (DMV) and nucleus ambiguus (NA) to ascertain if target neurotization was established. Results: The contralateral (left) intact vagus nerve proximal to the level of ansa cervicalis showed an average of 33 +/- 1 myelinated and 74 +/- 4 unmyelinated axons in 727 &mgr;m(2) sectional area of the nerve. In the heteroconnected nerve at the corresponding level just proximal to the anastomosis site, there was a marked increase in the number of small axons sprouting from the unmyelinated nerve fibers between 18 and 25 dpo. The number of these axonal sprouts appeared to decline at 32 dpo but its increase of 131 % was sustained until the late regeneration stage at 315 dpo when compared with the contralateral nerve serving as a control. The mean number of myelinated axons per area unit (727 &mgr;m(2)) was reduced to 18 at 3 dpo but was immediately restored to the normal range at 7 dpo. The retrograde labelling of neurons in both the DMV and NA was first detected at 22 dpo and was progressively increased peaking by about 67 dpo. Conclusions: We conclude that compared with the unmyelinated axons, the myelinated axons may acquire a superior interaction with the new target. Furthermore, the postoperative neurotization of tongue muscles may initiate and facilitate the retraction of the redundant axonal sprouts.  相似文献   
127.
Extended cervical mediastinoscopy in the staging of bronchogenic carcinoma   总被引:3,自引:0,他引:3  
BACKGROUND: Extended cervical mediastinoscopy (ECM) is a technique in the staging of bronchogenic carcinoma described first by Ginsberg in 1984. To update our experience we have prospectively evaluated our results on 106 patients who underwent the technique from 1985 to 1998. METHODS: The ECM technique is performed once the operability of the patient has been evaluated, according to the computed tomography findings. The intervention is carried out at the same time as a standard cervical mediastinoscopy through the same incision following the same technique as previously published. The ECM is considered positive when metastatic nodes or tumor involvement directly in the paraaortic or subaortic regions is detected and confirmed histologically. Negative cases of ECM and positive cases of standard cervical mediastinoscopy are excluded from this study. A false-negative ECM is defined as the presence of infiltrated adenopathies at the paraortic level detected on postoperative histologic study. RESULTS: We had performed ECM in 106 patients, and a total of 13 were subsequently excluded for the reasons stated above. Of the remaining cases, 26 were positive, 61 negative and 6 had false-negative results with no false-positive results. Sensitivity was 81.2%, specificity 100%, accuracy 93.3%, positive predictive value 100%, and negative predictive value 91%. There were no complications with the technique. CONCLUSIONS: We conclude that ECM is a useful technique for staging bronchogenic carcinoma that allows samples to be taken from paraortic and subaortic regions with minimally invasive techniques.  相似文献   
128.
129.
新型药用辅料微粉硅胶在药物制剂生产中的应用   总被引:8,自引:0,他引:8  
介绍了新型药用辅料-微粉硅胶的性能特点以及在药物制剂生产中的具体应用.微粉硅胶可以取代传统的抗结剂、助流剂,用以提高药物制剂的生产质量.  相似文献   
130.
Despite recent progress in the identification and characterization of numerous nasal biotransformation enzymes in laboratory animals, the expression of biotransformation genes in human nasal mucosa remains difficult to study. Given the potential role of nasal biotransformation enzymes in the metabolism of airborne chemicals, including fragrance compounds and therapeutic agents, as well as the potential interspecies differences between laboratory animals and humans, it would be highly desirable to identify those biotransformation genes that are expressed in human nasal mucosa. In this study, a global gene expression analysis was performed to compare biotransformation enzymes expressed in human fetal and adult nasal mucosa to those expressed in liver. The identities of a list of biotransformation genes with apparently nasal mucosa-selective expression were subsequently confirmed by RNA-polymerase chain reaction (PCR) and DNA sequencing of the PCR products. Further quantitative RNA-PCR experiments indicated that, in the fetus, aldehyde dehydrogenase 6 (ALDH6), CYP1B1, CYP2F1, CYP4B1, and UDP glucuronosyltransferase 2A1 are expressed preferentially in the nasal mucosa and that ALDH7, flavin-containing monooxygenase 1, and glutathione S-transferase P1 are at least as abundant in the nasal mucosa as in the liver. The nasal mucosal expression of CYP2E1 was also detected. These findings provide a basis for further explorations of the metabolic capacity of the human nasal mucosa for xenobiotic compounds.  相似文献   
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