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41.
闽产木立芦荟多糖的分离纯化及初步分析 总被引:14,自引:2,他引:12
目的 分离纯化及初步分析产木立芦荟中的多糖。方法 芦荟经沸水提取,醇沉,Sevage法去除蛋白质,Sephadex G-200柱色谱分离纯化,制得闽产木立芦荟多糖,以硫酸-苯酚法测定其总糖含量。结果 闽产木立芦荟多糖经紫外吸收光谱扫描具有多糖特征吸收峰,未见核酸和蛋白质吸收峰,多糖含量可达89.7%,初步分析由D-甘露糖和D-葡萄糖等单糖组成。结论 从闽产木立芦荟中可提取分离纯度较高的杂多糖。 相似文献
42.
Physiologic mechanism and preoperative prediction of new-onset dysphagia after laparoscopic Nissen fundoplication 总被引:2,自引:0,他引:2
Dennis Blom M.D. Jeffrey H. Peters M.D. Tom R. DeMeester M.D. Peter F. Crookes M.D. Jeffrey A. Hagan M.D. Steven R. DeMeester M.D. Cedric Bremner M.D. 《Journal of gastrointestinal surgery》2002,6(1):22-28
The aim of this study was to determine whether preoperative physiologic factors can account for and be used to predict the
development of postoperative dysphagia after laparoscopic Nissen fundoplication. One hundred sixty-three patients with gastroesophageal
reflux disease underwent laparoscopic Nissen fundoplication with a median follow-up of 14 months (range 6 to 81 months). Preoperative
dysphagia was present in 37% (60 of 163) and was relieved in all but five patients (92%). Female sex (P = 0.01) and the presence of a stricture (P = 0.02) were the only preoperative variables associated with the presence of preoperative dysphagia. Eight percent (8 of
103) of patients without preoperative dysphagia developed new-onset dysphagia, and of these 63% (5 of 8) had a normal lower
esophageal sphincter (LES) (pressure >6 mm Hg; length >2 cm; abdominal length >1 cm). New-onset dysphagia was significantly
more common in patients with a normal LES (22% [5 of 23] vs. 4% [3 of 80], P = 001). Patients with a normal LES had almost a sixfold increase in the risk of developing dysphagia as those with an abnormal
LES (relative risk = 5.8). Only a preoperative normal LES (P = 0.02) or mean LES pressures (P = 0.04) were positively associated with the development of postoperative dysphagia. The severity of this dysphagia also showed
a strong positive trend of increasing with mean preoperative LES pressures (P = 0.07). Finally, preoperative LES pressure significantly correlated with postoperative LES pressure (r = 0.48, P = 0.01) and with mean residual LES (nadir) pressure (r = 0.33, P = 0.05) offering insight into the mechanism of this dysphagia. In conclusion, preoperative LES parameters play a role in
the development of dysphagia after laparoscopic Nissen fundoplication. Patients with a normal LES or high mean LES pressures
are at increased risk for developing this complication and should be informed of this before laparoscopic Nissen fundoplication.
Presented at the Forty-Second Annual Meeting of The Society for Surgery of the Alimentary Tract, Atlanta, Ga., May 20–23,
2001. 相似文献
43.
成人成骨细胞与珊瑚羟基磷灰石的体外生物相容性 总被引:13,自引:2,他引:11
目的:研究成人骨髓成骨细胞与珊瑚羟基磷灰石(carolline hydroxyapatite,CHA)在体外培养条件下的生物相容性。方法:抽取健康成人骨髓组织,置于含体积分数为10%胎牛血清的DMEM培养基中培养,传代后改用含地塞米松、β-甘油磷酸钠和维生素C的条件培养基培养,分为CHA复合细胞组和单纯细胞组,不同时间用倒置相关显微镜,HE染色光镜及扫描电镜观察,MTT法进行细胞增殖测定,并进行细胞微量蛋白含量和碱性磷酸酶的定量检测,结果:成人骨髓成骨细胞体外培养时复合或不复合CHA均生长良好,表现出典型成骨细胞的形态特征和生物学特性,CHA利于细胞的贴附,生长与增殖,并对细胞的功能无不良影响,结论:CHA是较理想的骨组织工程支架材料,成骨细胞复合CHA用于骨缺损的修复,具有广阔的临床应用前景。 相似文献
44.
Bradley J Catalone Shendra R Miller Mary Lee Ferguson Dan Malamud Tina Kish-Catalone Nina J Thakkar Fred C Krebs Mary K Howett Brian Wigdahl 《Biomedicine & Pharmacotherapy》2005,59(8):430-437
C31G, which has potent activity against the human immunodeficiency virus type 1 (HIV-1) and an established record of safety in animal studies and human trials, is a microbicidal agent comprised of a buffered equimolar mixture of two amphoteric, surface-active agents: an alkyl amine oxide (C14AO) and an alkyl betaine (C16B). Studies of long-term in vitro exposure to C31G and its constituents have suggested that the components of C31G may contribute differentially to its toxicity and efficacy. In the present studies, in vitro assays of cytotoxicity and anti-HIV-1 activity demonstrated that C16B was slightly less cytotoxic compared to either C31G or C14AO, whereas the anti-HIV-1 activities of C31G and its individual constituents were similar. In the murine model of cervicovaginal microbicide toxicity, in vivo exposure to C14AO resulted in severe cervical inflammation followed by a delayed disruption of the columnar epithelium. In contrast, exposure to C16B caused severe cervical epithelial disruption and a secondary, less intense inflammatory response. These results demonstrate that (i) there are both mechanistic and temporal differences in toxicity associated with the components of C31G not necessarily predicted by in vitro assessments of cytotoxicity and (ii) contributions of each component to the anti-HIV-1 activity of C31G appear to be equal. In addition, these findings indicate that direct and indirect mechanisms of in vivo toxicity can be observed as separate but interrelated events. These results provide further insight into the activity of C31G, as well as mechanisms potentially associated with microbicide toxicity. 相似文献
45.
46.
Cristina Benatti Silvia Alboni Giacomo Capone Daniela Corsini Federica Caggia Nicoletta Brunello Fabio Tascedda Joan M.C. Blom 《International journal of developmental neuroscience》2009,27(7):661-668
Protracted or recurrent pain and inflammation in the early neonatal period may cause long-lasting changes in central neural function. However, more research is necessary to better characterize the long-term behavioral sequelae of such exposure in the neonatal period. Objectives: (1) to study whether timing of postnatal exposure to persistent inflammation alters responsiveness to thermal pain in the adult animal; (2) to assess whether animals experiencing early postnatal chronic inflammation display altered anxiety related behavior; (3) to study the importance of genetic background. Newborn mice (outbred strain, CD1 and F1 hybrid strain, B6C3F1) received an injection of Complete Freund's Adjuvant (CFA) or saline on either postnatal day 1 or 14 (PND1; PND14) into the left hind paw. Pain to radiant heat and anxiety were examined in 12-week-old adult animals. Adult baseline PWL was significantly decreased in CD1 mice exposed to CFA on PND 1 and 14 as compared to their saline treated counterparts. B6C3F1 mice exposed to CFA on PND14 showed markedly reduced baseline PWL compared to the PND14 saline group. Persistent inflammation experienced by B6C3F1 mice on PND1 failed to affect baseline adult thermal responsiveness. Adult mice, CD1 and B6C3F1, displayed low anxiety traits only if they had been exposed to persistent inflammation on PND1 and not on PND14. Our research suggests a role for genetic background in modulating long-term behavioral consequences of neonatal persistent inflammation: the data support the hypothesis that pain experienced very early in life differentially affects adult behavioral and emotional responsiveness in outbred (CD1) and hybrid mice (B6C3F1). 相似文献
47.
48.
目的评价屈颈MRI对青年性上肢远端肌萎缩症的诊断价值。方法男性患者5例,平均年龄21岁,临床表现为一侧或两侧上肢远端肌萎缩。对照组为健康志愿者,21岁男性8例。2组均行常规及屈颈颈椎MR平扫,矢状、轴面SET1WI、T2WI、液体衰减反转恢复(FLAIR)序列扫描。结果常规颈椎扫描:5例患者下段颈髓变细;屈颈位MR扫描:下颈段颈6以下脊髓前屈、变扁平,矢状径4~6mm,硬膜囊后壁前移,硬膜后间隙明显增宽,可见多发条状、迂曲流空信号影及软组织信号。对照组:常规扫描,下颈段脊髓(颈6~胸2)可见颈膨大,屈颈位脊髓略变细(6~7mm),硬膜囊后壁无前移,硬膜后间隙未见扩张血管影。结论屈颈MRI有助于显示下颈段脊髓及硬膜囊改变,结合临床资料可准确诊断青年性上肢远端肌萎缩症。 相似文献
49.
Dan Greitz 《Child's nervous system》2007,23(5):487-489
Objective This study aims to question the generally accepted cerebrospinal fluid (CSF) bulk flow theory suggesting that the CSF is exclusively
absorbed by the arachnoid villi and that the cause of hydrocephalus is a CSF absorption deficit. In addition, this study aims
to briefly describe the new hydrodynamic concept of hydrocephalus and the rationale for endoscopic third ventriculostomy (ETV)
in communicating hydrocephalus.
Critique The bulk flow theory has proven incapable of explaining the pivotal mechanisms behind communicating hydrocephalus. Thus, the
theory is unable to explain why the ventricles enlarge, why the CSF pressure remains normal and why some patients improve
after ETV.
Hydrodynamic concept of hydrocephalus Communicating hydrocephalus is caused by decreased intracranial compliance increasing the systolic pressure transmission into
the brain parenchyma. The increased systolic pressure in the brain distends the brain towards the skull and simultaneously
compresses the periventricular region of the brain against the ventricles. The final result is the predominant enlargement
of the ventricles and narrowing of the subarachnoid space. The ETV reduces the increased systolic pressure in the brain simply
by venting ventricular CSF through the stoma. The patent aqueduct in communicating hydrocephalus is too narrow to vent the
CSF sufficiently. 相似文献
50.
Rapid growth in biomedical research coupled with dramatic advancement in biotechnology has significantly improved our understanding of the molecular basis involving cancer development and progression. This improvement has led to the discovery of new molecular markers for cancer diagnosis and prognosis as well as new molecular targets for cancer treatment and intervention. Continuous emergence of some new developing area in molecular profiling, new therapeutic agents, tissue microenvironment and systems biology have made significant progress in clinical oncology. Clinical research and investigation that focus on these new developments have begun to show exciting results that indicate future promises in improving patient management and survival. 相似文献