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991.
This study aimed to compare the variation of cancellous bones at four skeletal sites: lumbar vertebra, femoral neck, mandibular angle and rib in ovariectomized sheep. Sixteen adult sheep were randomly divided into two groups: eight sheep were ovariectomized served as experimental group; the other eight untreated sheep were served as control group. Bone mineral density was assessed by dual-energy X-ray absorptiometry on lumbar vertebrae at baseline and twelve months after ovariectomy. After 12 months, lumbar vertebrae L3 and L4, femoral necks, mandibular angles and the fourth ribs were harvested for micro-CT scanning, histological analysis and biomechanical test. The results showed that bone mineral density of lumbar vertebra decreased significantly in twelfth month (p < 0.05). The results of micro-CT showed that the bone volume/total volume decreased by 45.6%, 36.1% 21.3% and 18.7% in lumbar vertebrae, femoral necks, mandibular angles and ribs in experimental group (p < 0.05) respectively. The trabecular number showed the same downtrend (p < 0.05). Histological analysis showed trabecular area/tissue area decreased by 32.1%, 23.2% and 20.7% in lumbar vertebrae, femoral necks and mandibular angles respectively (p < 0.05), but no significant difference in ribs. Specimens elastic modulus from lumbar vertebra, femoral neck and mandibular angle were 952 ± 76 MPa (628 ± 70 MPa), 961 ± 173 MPa (610 ± 72 MPa) and 595 ± 60 MPa (444 ± 31 MPa) in control group (experimental group) respectively. These datum indicated that the sensibility of cancellous bones to oestrogen deficiency in ovariectomized sheep was site-specific on a pattern as follows: lumbar vertebra, femoral neck, mandibular angle and rib.  相似文献   
992.
993.
目的:探讨艾滋病合并口腔念珠菌病的临床特点和诊治转归。方法:回顾性研究从2012-09~2013-03北京地坛医院收治的31例艾滋病合并口腔念珠菌感染者的临床资料,包括一般资料、临床特征、口腔表现、CD4细胞计数、机会性感染状况、抗真菌治疗转归等。结果:31例患者中30例 CD4细胞计数小于200个/μl,有29例合并多种机会性感染。临床表现30例为假膜型,1例为红斑型,2例假膜型合并口角炎型。抗真菌治疗后,8例病损缩小,23例病损完全消失,3例停药后复发。结论:艾滋病合并口腔念珠菌病临床上多见于 CD4细胞<200个/μl 的患者,临床表现以假膜型为主,常合并有其他部位的多种机会性感染。这类患者抗真菌治疗有效。  相似文献   
994.

OBJECTIVE:

We examined the demographic and clinical profiles of Parkinson''s disease in Shanghai, China, to assist in disease management and provide comparative data on Parkinson''s disease prevalence, phenotype, and progression among different regions and ethnic groups.

METHODS:

A door-to-door survey and follow-up clinical examinations identified 180 community-dwelling Han-Chinese Parkinson''s disease patients (104 males, 76 females).

RESULTS:

The average age at onset was 65.16±9.60 years. The most common initial symptom was tremor (112 patients, 62.22%), followed by rigidity (38, 21.11%), bradykinesia (28, 15.56%) and tremor plus rigidity (2, 1.11%). Tremor as the initial symptom usually began in a single limb (83.04% of patients). The average duration from onset to mild Parkinson''s disease (Hoehn-Yahr phase 1–2) was 52.74±45.64 months. Progression from mild to moderate/severe Parkinson''s disease (phase≥3) was significantly slower (87.07±58.72 months; p<0.001), except for patients presenting initially with bradykinesia (53.83±24.49 months). Most patients (149/180, 82.78%) took levodopa with or without other drugs. The Hamilton Anxiety Scale revealed symptoms of clinical anxiety in 35 patients, and the Hamilton Depression Scale revealed depressive symptoms in 88 patients. The depressed or anxious subgroup (123 patients) demonstrated a significantly younger age at onset (55.54±7.68 years) compared with the overall mean (p<0.05).

CONCLUSION:

Unilateral limb tremor was the most common initial symptom, and motor function deteriorated slowly over ≈4−9 years. Earlier-onset patients experience greater psychiatric dysfunction.  相似文献   
995.
This study is to investigate the expression of miR-21 in nasopharyngeal carcinoma (NPC) cells, and the effect of miR-21 in the biological behavior and expression of B-cell lymphoma 2 (BCL2) in NPC cells. Paired NPC and adjacent non-tumor tissues were obtained from 53 patients who underwent primary surgical resection of NPC tissues. Luciferase reporter assay was performed to test whether BCL2 is a direct target of miR-21. Methylthiazolyl blue tetrazolium assay and colony assay were used to evaluate the effect of miR-21 on NPC cell proliferation. Transwell and wound-healing assays were carried out to test the effect of low expression of miR-21 on cancer cell migration and invasion. QRT-PCR and Western blotting were used to measure the levels of mRNA and protein expression, respectively. Tumor tissues showed a positive correlation between the levels of miR-21 and BCL2 protein expression. Cells transfected with miR-21 inhibitor healed slower compared the control (P < 0.05). In addition, cell migration was notably inhibited by the down-regulation of miR-21 in vitro (P < 0.05). The reduction in miR-21 expression showed a remarkable effect on the biological behavior of NPC cell clone formation (P < 0.05). Low expression of miR-21 by transfection with miRNA expression plasmid led to a decrease in BCL2 expression, which was accompanied by reduced migration and proliferation of the cancer cells. Our results demonstrated that miR-21 inhibitor down-regulated BCL2 expression level, suggesting that BCL2 might be a target gene for the initiation and development of NPC cells.  相似文献   
996.
Purpose: Charcot-Marie-Tooth disease (CMT) is the most common type of inherited peripheral neuropathy and has a high degree of genetic heterogeneity. CMT with concurrent diabetes mellitus (DM) is rare. The purpose of this study is to explore the genetic, clinical and pathological characteristics of the patients with CMT and concurrent DM. Methods: We investigated gene mutations (the peripheral myelin protein 22 gene, myelin protein zero gene, lipopolysaccharide-induced tumor necrosis factor-α factor gene, early growth response gene and the neurofilament light chain gene loci) of a relatively large and typical Chinese family with CMT1 and concurrent DM2. From the literature, we also retrieved all reported families and single cases with CMT and concurrent DM. We comprehensively analyzed the characteristics of total 33 patients with CMT and concurrent DM, and further compared these characteristics with those of patients of diabetic peripheral neuropathy (DPN). Results: Patients with CMT and concurrent DM had some relatively independent characteristics and pathogenic mechanisms. So we designated that kind of characteristic demyelinating CMT which accompanies DM as Yu-Xie syndrome (YXS), a new specific clinical subtype of CMT. Conclusion: CMT is an etiologic factor of DM, even though the intrinsic association between CMT and DM still remains further exploration.  相似文献   
997.
Regulator of G-protein signaling 6 (RGS6), a member of a family of RGS proteins, has been reported to involve in multiple processes during tumor development. However, its role in pancreatic cancer has not been studied yet. In this study, we aimed to investigate the expression of RGS6 in pancreatic cancer and its role in predicting outcomes of patients with pancreatic cancer. We first measured the expression of RGS6 mRNA in 20 cases of tumor tissues and matched adjacent non-tumorous tissues by quantitative real-time PCR and examined RGS6 protein by immunohistochemistry in tissue microarrays containing 90 tumor and 90 paired adjacent non-tumor tissues. Decreased RGS6 mRNA detected in primary tumor, compared with their non-tumor counterparts. In addition, decreased RGS6 protein expression was associated with tumor differentiation (P = 0.027), pT classification (P = 0.034), smoking status (P = 0.041) and a poor survival (P = 0.007). Cox proportional hazards regression modeling analysis revealed that lymph node metastasis (P = 0.001; hazard ratio, 2.347, 95% CI, 1.387-3.972), tumor differentiation (P = 0.015; hazard ratio, 0.505, 95% CI, 0.291-0.876) and RGS6 expression (P = 0.048; hazard ratio, 0.567, 95% CI, 0.324-0.994) were three independent prognostic factors. Taken together, these date demonstrate that RGS6 decreases in tumor tissue and may serve as a novel biomarker for outcomes in pancreatic cancer patients and be a potential therapeutic target potential therapeutic target.  相似文献   
998.
Wheat-dependent exercise-induced anaphylaxis (WDEIA) usually occurs 1 to 4 hours after wheat ingestion and the pathophysiology of WDEIA remains unknown. It is recommended that WDEIA patients refrain from exercise for 4 to 6 hours after wheat ingestion. We report a case of a 51-year-old man who experienced 5 anaphylaxis attacks; two of which occurred 10 to 24 hours after wheat ingestion and exercise. He has a history of chronic gastroenteritis that responds well to antihistamine drugs but not proton pump inhibitors (PPIs) and prokinetic agents. Abdominal CT results implied the possibility of superior mesenteric artery syndrome. We suggest that WDEIA occurs 6 hours after wheat ingestion in cases compounded by obstructive gastrointestinal diseases.  相似文献   
999.
Wheat straw is considered an abundant lignocellulosic biomass source in China. However, its recalcitrance hinders the degradation of wheat straw by enzymes and microbes. In this study, we investigated the optimum steam explosion conditions of pretreated wheat straw by response surface methodology to improve its nutrition level as a feedstuff for the ruminant industry or as a feedstock for biofuel production. The highest volatile fatty acid (VFA) yield (30.50 mmol L−1) was obtained at 2.3 MPa, 90 s and a moisture content of 36.46%. Under optimal conditions, steam explosion significantly altered the fermentation parameters in vitro. Ionic chromatography showed that pretreating wheat straw could improve the production of fermentable sugar, which was ascribed to the degradation of cellulose and hemicellulose. In addition, high throughput 16S rRNA amplicon sequencing analysis revealed that steam explosion changed the microbial community and enhanced the colonization of cellulolytic bacteria. Our findings demonstrated that steam explosion pretreatment could greatly improve the digestibility of wheat straw by facilitating sugar production and microbial colonization.

Wheat straw is considered an abundant lignocellulosic biomass source in China.  相似文献   
1000.
目的:研究酸蚀和微弧氧化单独或联合应用对纯钛表面处理后进行烤瓷,观察其表面粗糙度并分析其钛瓷结合强度。方法:将50个纯钛试片(25mm×5mmx0.5mm)随机均分为5组,表面用碳化硅砂纸抛光后110μmA12O3进行喷砂处理,再进行喷砂、酸蚀、微弧氧化、酸蚀后微弧氧化及微弧氧化后酸蚀处理分别为A到E组,用粗糙度测试仪测量各组的粗糙度值并进行统计学分析,扫描电镜观察试件的表面形貌。行瓷粉烧结(厚度控制在1mm),然后对钛瓷间的三点弯曲结合强度进行测试并进行统计学分析,用扫描电镜观察钛瓷分离面的的表面形貌。结果:酸蚀使纹路更清晰,粗糙度增加。C组纯钛表面形成许多孔洞,孔洞较大,大小基本一致。C组除大孔洞外还存在许多小孔洞,均匀致密。D组表面孔洞大小不一,较致密,存在凹陷,边缘不规则,个别相邻孔洞之间可见微裂纹。与喷砂相比,微弧氧化处理使纯钛与瓷的结合强度差异有统计学意义(P〈0.05),而酸蚀处理的钛表面与瓷的结合强度增加,但与对照组差异无统计学意义(P〉0.05)。结论:酸蚀和微弧氧化联合处理与单独微弧氧化处理钛瓷间的结合强度差异无统计学意义,说明微弧氧化处理更利于钛瓷间的结合。  相似文献   
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