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21.
柴胡皂甙m和柴胡皂甙n的结构鉴定   总被引:4,自引:0,他引:4  
从黑柴胡(Bupleurum smithii Wolff)根中分得二个新三萜皂甙。根据理化性质和波谱数据,分别鉴定为3β,23,28-三羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃葡萄糖基-(1→3)-β-D-吡喃呋糖甙,命名为柴胡皂甙m(saikosaponin m,IV),和3β,16β,23,28-四羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃葡萄糖基-(1→6)-[α-L-吡喃鼠李糖基-(1→4)]-β-D-吡喃葡萄糖甙,命名为柴胡皂甙n(saikos-aponinn,IX)。  相似文献   
22.
Aims. This article aims to review the literature published to date on the types, current use, the biomechanical effects and adverse effects of maternity support belts for low back pain during pregnancy, to identify future research directions. Background. Lumbar/pelvic support belts are frequently recommended for the prevention and treatment of low back pain during pregnancy. Design. Systematic review. Methods. MEDLINE, CINAHL, the Cochrane Library and patents databases were electronically searched. Results. Maternity support belts belong to one of the four main types of maternity support garments, which are widely commercially‐available. Current research showed limited evidence in support of the commercial maternity products regarding the effectiveness in the prevention and/or treatment of low back pain during pregnancy, other than that from the manufacturers. However, potential stabilisation effect of maternity support belt was demonstrated in some studies. Adverse effects reported include increased pain, fetal heart rate changes, skin irritation and discomfort. Conclusions. There is insufficient scientific evidence to conclude that wearing maternity support belts reduces pregnancy‐related low back pain and/or pelvic girdle pain. Future research directions in the area of biomechanics and physiology are recommended. Relevance to clinical practice. This review provides comprehensive understanding of the effectiveness of maternity support belts for the relief of low back pain during pregnancy which will facilitate healthcare professionals in providing evidence‐based advice to their patients.  相似文献   
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Background:

Hand dermatitis is a common, chronic relapsing skin disease, resulting from a variety of causes including endogenous predisposition and environmental exposures to irritants and allergens. Physical activities have been reported to be beneficial for patients with hand dermatitis.

Objectives:

We aim to evaluate the association between self-reported physical activities and hand dermatitis using the 2003-2004 National Health and Nutrition Examination Survey (NHANES) database.

Methods:

Information regarding 2,688 participants aged 20 to 59 years from the 2003-2004 NHANES cycle were retrieved and analyzed. Diagnosis of hand dermatitis was based on standardized photographs of the hands read by two dermatologists. Physical activity during leisure time for the prior 30 days was assessed using standardized questionnaire. Based on the suggested MET scores provided for each response in the questionnaire section of the NHANES methodology, the MET scores for average level of physical activities, walking/bicycling, and performing tasks around home/yard for the past 30 days was calculated.

Results:

There were 42 (1.56%) diagnosed cases of active hand dermatitis among the 2,688 participants. Those who reported recent vigorous or moderate physical activities were less likely to have a diagnosis of active hand dermatitis (OR: 0.436, 95% CI: 0.200 to 0.947, P = 0.036 and OR: 0.489, 95% CI: 0.261 to 0.916, P = 0.025, respectively). This negative association remained statistically significant even after adjusting for age, gender, ethnic groups and atopic diathesis.

Conclusions:

Moderate and vigorous levels of physical activities appeared to be beneficial for hand dermatitis. Therefore, it is important to advise patients with active hand dermatitis to remain physically active. However, clinicians should also be cognizant of the fact that the heat and sweat generated from physical activities might also exacerbate the condition.  相似文献   
25.
OBJECTIVE: To compare the vaginal configuration on magnetic resonance imaging following transvaginal sacrospinous fixation (SSF), posterior intravaginal slingplasty (PIVS) (infracoccygeal sacropexy) and sacrocolpopexy (SCP). MATERIALS AND METHODS: Twenty-one patients with vault prolapse requiring surgical treatment were randomly assigned in a balanced way to undergo SSF (n = 7), PIVS (n = 7) or SCP (n = 7). The magnetic resonance imaging of the pelvis were performed preoperatively and at 6-12 weeks postoperatively to assess the vaginal configuration using the method described previously. The two main angles measured were: (i) the angle between the lower vagina and pubococcygeal line 'd-angle' (normal: 53 +/- 15 degrees ); and (ii) the angle between the lower and upper vagina planes 'e-angle' (normal: 145 +/- 7 degrees ). RESULTS: The mean preoperative/postoperatively measured d-angles were 69 degrees /62 degrees, 58 degrees /70 degrees, and 49 degrees /52 degrees for SSF, PIVS and SCP, respectively. The corresponding means for the e-angle were 173 degrees /215 degrees, 189 degrees /146 degrees, and 205 degrees /149 degrees. The changes of the e-angles proved to be statistically significant (P < 0.05) in each surgical group, while no significant change in the d-angle could be found in any of the three groups. CONCLUSIONS: Significant improvements in the restoration of vaginal configuration were achieved in patients who underwent PIVS or SCP. Sacrospinous fixation in contrast seems to increase anatomical distortion of the vaginal configuration.  相似文献   
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There is no surrogate marker in serum for defining disease activity in scleroderma (SSc). Nitric oxide (NO), which regulates vasodilation and possesses pro-inflammatory actions, has been implicated in the pathogenesis of SSc. We compared serum NO x (total nitrate and nitrite) level in SSc patients to healthy controls and evaluated its correlation with detailed symptomatology and scoring systems for various organ involvement. Symptoms and physical findings that suggested disease activity in regard to various organs were documented. Lung function test, high-resolution computed tomographic (HRCT) scan of thorax and echocardiography were performed. Serum NO x was measured by chemiluminescence. Serum NO x levels in SSc (n = 43) were significantly higher (72.4 ± 47.8 μM) than age- and sex-matched controls (n = 41; 37.1 ± 13.5 μM; p < 0.001). Serum NO x were not found to be associated with lung fibrosis defined by lung function parameters or inflammation and fibrosis scores on HRCT. Twenty-two patients were found to have elevated serum NO x level defined as mean ± 2 SD of normal controls. Logistic regression analysis revealed that age (OR 1.12, p = 0.02) and elevated pulmonary arterial pressure (PAP) (n = 9; OR 145.3, p = 0.01) were predictive factors for elevated serum NO x . Prednisolone use was associated with lower serum NO x level (OR 0.06, p = 0.04). Elevated PAP of increasing severity was found to be associated with higher level of serum NO x (p = 0.004 by trend). Serum NO x in SSc patients were elevated compared to healthy controls. Serum NO x level was determined by multiple factors including age, prednisolone use, and elevated PAP.  相似文献   
29.
目的了解编码SAG3的重组质粒和IL-2基因佐剂在小鼠体内的免疫反应,为进一步的核酸疫苗及免疫学研究创造条件。方法将编码SAG3的质粒和鼠源性IL-2表达载体以100μg的剂量感染小鼠,3周中两次以相同的剂量加强免疫,分别以PBS和空质粒pcDNA3.1感染。采用ELISA法测定抗体水平、亚型、IFN-γI、L-4和IL-2的含量,RT-PCR方法检测注射部位目的基因的转录,所有鼠均由强毒力ZS2株弓形虫感染。结果SAG3表达质粒3次免疫后鼠体内特异IgG水平明显上升,IL-2表达质粒的联合使用导致IgG2a水平的升高和IFN-γ的产生,提高了其分泌IL-2的水平,但对IL-4的水平产生轻微的影响;RT-PCR显示首次使用导致IgG2a水平的升高和IFN-γ的产生,提高了其分泌IL-2的水平,但对IL-4的水平产生轻微的影响;RT-PCR显示首次免疫15天后,目的基因在肌肉组织中仍有表达;混合质粒注射和小鼠抗弓形虫感染的存活时间延长。结论由SAG3 DNA诱导的免疫应答因IL-2表达质粒的共同注射而增强,DNA疫苗和适当细胞因子的共注射对抵抗弓形虫感染的效果值得进一步研究。  相似文献   
30.
It is proposed that epithelial changes induced by gastroesophageal reflux disease are related to the pH environment of the esophageal lumen. We hypothesized that the various types of esophageal epithelium are associated with specific pH environments that induce their formation. The aim of this study was to compare the luminal pH environment to the histology of the distal esophageal epithelium in patients with gastroesophageal reflux disease. A total of 197 symptomatic patients with increased esophageal acid exposure on 24-hour pH monitoring were grouped according to the histology based on biopsies from the distal esophagus: 17 with squamous epithelium, 126 with cardiac epithelium (CE), and 54 with Barrett's epithelium (BE). All were free of Helicobacter pylori infection and monitored off acid suppression therapy. Acid exposure was expressed as the percent of time the luminal pH was at intervals of 0–1, 1–2, 2–3, 3–4, 4–5, 5–6, and 6–7 over a 24-hour period. Patients with BE spent significantly more time at pH intervals 2–3, 3–4, and 4–5 than those with CE. This pattern switched at pH interval 5–6, where patients with cardiac mucosa spent more time than those with BE. Patients with squamous and CE had similar pH exposure at all intervals. Patients with BE have significantly longer exposure time at the pH interval of 2 to 5 compared to those with cardiac and squamous epithelium. This suggests that the exposure of stem cells to a luminal pH between 2 and 5 may trigger the differentiation of CE into intestinalized CE.  相似文献   
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