Relationship of energy charge and toxin content of Microcystis aeruginosa in nitrogen-limited or phosphorous-limited cultures.

Effects of nitrogen-limitation and phosphorus-limitation on microcystin (MC) content and energy charge (EC) of the Microcystis aeruginosa were investigated in batch cultures and semi-continuous cultures. In batch cultures, nitrogen-limitation retarded the MC synthesis and phosphorus-limitation had little effects on MC production. The EC remained constant in nitrogen-limited cultures, while it decreased largely when phosphorus was extinct in phosphorus-limited culture. In the semi-continuous cultures, MC production in nitrogen- and phosphorus-limited cultures increased with the increase of dilution rate; however, MC content in phosphorus-limited cultures was more than that in nitrogen-limited cultures. The EC in nitrogen-limited cultures remained constant and in phosphorus-limited cultures increased with the increase of dilution rate. In phosphorus-limited semi-continuous cultures, a direct relationship between EC and MC content was demonstrated. No correlation was observed in nitrogen-limited semi-continuous cultures. Based on the above analysis, a mechanism of nitrogen and phosphorus effect on the MC synthesis was suggested, that the MC synthesis was determined by the combination of necessary enzymes and precursors and EC.     

参芪杀白汤为主联合化疗治疗急性白血病合并脾周围炎临床研究

目的:观察参芪杀白汤为主联合化疗治疗白血病伴发脾周围炎患者临床疗效及患者脾肿大范围、疼痛程度、局部皮温及彩超脾周围炎相关表现的治疗前后改善情况。方法:在DA方案或VDCP±L-Asp方案化疗基础上,采用益气养阴,化瘀消癥中药,自拟参芪杀白汤内服、丹香解毒消癥散外敷治疗伴脾周围炎急性髓细胞白血病或急性淋巴细胞白血病。结果:白血病疗效表明,观察组CR率69.0%,观察组46.3%;总有效率观察组88.1%,明显优于对照组(68.3%,P<0.05);脾周围炎治疗效果观察组痊愈率59.5%,对照组39.0%;总有效率观察组92.9%,优于对照组(82.9%,P<0.05)。结论:益气养阴、化瘀消癥中药内服外用治疗急性白血病伴发脾周围炎可提高完全缓解率,既可清热解毒通络以止痛,又可软坚消癥治疗辅助治疗白血病,且未见明显不良反应。     

The relationship between estimated and registered natural head position

OBJECTIVE: To study the inherent relationship between registered and estimated natural head position and further explore the nature of natural head position. MATERIALS AND METHODS: Thirty-one pretreated patients were included in this study. Both registered natural head position (RNHP) and estimated natural head position (ENHP) were obtained. For RNHP, mirror orientation was used to help to adjust the subject's head position. For ENHP, two approved standard photographs were studied by the assessors before estimation. Correlation analysis was used to analyze the relationship between two angles: Rphoto/Rxray and Ephoto/ Eray. RESULTS: A significant correlation was found between RNHP and ENHP, both on the photographs and on the cephalograms. CONCLUSION: There is a strong correlation between RNHP and ENHP. RNHP is the subjective perception of the subject and gets some objective meaning by mirror orientation. ENHP is the subjective perception of assessors and gets objective meaning by a standardization session in advance. The mirror orientation of RNHP and the advance standard study of ENHP are crucial for validity and accuracy of NHP as an extracranial reference plane.     

Nuclear receptors in the multidrug resistance through the regulation of drug-metabolizing enzymes and drug transporters

Chemotherapy is one of the three most common treatment modalities for cancer. However, its efficacy is limited by multidrug resistant cancer cells. Drug metabolizing enzymes (DMEs) and efflux transporters promote the metabolism, elimination, and detoxification of chemotherapeutic agents. Consequently, elevated levels of DMEs and efflux transporters reduce the therapeutic effectiveness of chemotherapeutics and, often, lead to treatment failure. Nuclear receptors, especially pregnane X receptor (PXR, NR1I2) and constitutive androstane activated receptor (CAR, NR1I3), are increasingly recognized for their role in xenobiotic metabolism and clearance as well as their role in the development of multidrug resistance (MDR) during chemotherapy. Promiscuous xenobiotic receptors, including PXR and CAR, govern the inducible expressions of a broad spectrum of target genes that encode phase I DMEs, phase II DMEs, and efflux transporters. Recent studies conducted by a number of groups, including ours, have revealed that PXR and CAR play pivotal roles in the development of MDR in various human carcinomas, including prostate, colon, ovarian, and esophageal squamous cell carcinomas. Accordingly, PXR/CAR expression levels and/or activation statuses may predict prognosis and identify the risk of drug resistance in patients subjected to chemotherapy. Further, PXR/CAR antagonists, when used in combination with existing chemotherapeutics that activate PXR/CAR, are feasible and promising options that could be utilized to overcome or, at least, attenuate MDR in cancer cells.     

基因相关临床研究中的伦理审查要点

根据我院伦理委员会在临床科研中遇到的涉及人的基因相关性研究中凸显的问题,总结了基因临床研究在伦理审查时的要点,即受试者自主选择权,体现在研究结果的知晓权及生物样本库捐赠者的自主权。基因临床研究同时应注意遗传资源的保护,研究成果的公平原则,同时应便于研究者实际操作。归纳了基因相关研究项目在设计方案及知情同意书时应注意的基本要点,阐述了基因相关性临床研究规范性制度建设的重要性。     

骨性Ⅱ类错牙合下颌牙弓与基骨形态相关性的三维测量研究

目的 用三维数字化模型测量的方法探讨骨性Ⅱ类错牙合畸形患者的下颌牙弓弓形与基骨弓形间的相互关系。方法 对35例骨性Ⅱ类错牙合畸形患者治疗前下颌模型进行扫描,获得三维数字模型,对右侧第一磨牙至左侧第一磨牙的FA点（代表牙弓）、WALA点（代表基骨）进行标定并映射到参考平面得到FA和WALA的映射点,分析其牙弓弓形与基骨弓形及其相关性,并对牙弓和基骨弓形进行曲线拟合。结果 骨性Ⅱ类的下颌牙弓弓形曲线与基骨弓形曲线相关度在尖牙区为0.534,磨牙区为0.873。牙弓与基骨尖牙间宽度的差异无统计学意义（P=0.481）,而牙弓与基骨磨牙间宽度的差异具有统计学意义（P<0.01）。牙弓弓形拟合曲线的曲率半径r为15.194,回归系数R2为0.912;基骨弓形拟合曲线的r为20.250,R2为0.947。结论 骨性Ⅱ类错牙合畸形患者下颌牙弓弓形与对应的基骨弓形在磨牙区高度相关,在尖牙区中度相关;基骨尖牙间宽度与牙弓尖牙间宽度无明显差异,基骨磨牙间宽度则明显大于牙弓磨牙间宽度。     

睫状神经营养因子对周围神经损伤后功能恢复的影响

目的：研究睫状神经营养因子（ＣＮＴＦ）对受损周围神经功能恢复的影响。方法：将８０只大鼠左侧坐骨神经切断后行神经外膜吻合,随机分为两组。实验组腹腔内注入基因重组人ＣＮＴＦ,对照组注入等量生理盐水（ＮＳ）。术后行坐骨神经功能指数（ＳＦＩ）测定、电生理检测、轴突图像分析及霍乱毒素－辣根过氧化物酶（ＣＢ－ＨＲＰ）逆行追踪。结果：ＣＮＴＦ组ＳＦＩ恢复率、各项电生理及轴突图像分析指标、ＣＢ－ＨＲＰ标记的脊髓前     

局部注射神经生长因子及碱性成纤维生长因子对大鼠胫骨骨折愈合的影响

目的 探讨局部注射神经生长因子(NGF)及碱性成纤维生长因子(BFGF)对大鼠胫骨骨折愈合的影响及其机制。方法 选取12周龄清洁级成熟雄性SD大鼠 48 只,用数字表法随机分为NGF 组、BFGF组、NGF+BFGF组、对照组4组,各12只;每组大鼠按观察时间点不同随机分为术后2 周及术后4 周2个亚组,每亚组6只。 48 只大鼠均建立左胫骨骨折模型,并行1 mm克氏针髓内内固定。术后第3 天于骨折断端周围局部经皮注射给药:NGF组注射NGF 0.8 μg+0.3 mL生理盐水,BFGF组注射BFGF 1.2 μg+0.3 mL生理盐水,NGF+BFGF组注射NGF 0.8 μg+BFGF 1.2 μg+0.3 mL生理盐水,对照组注射0.3 mL生理盐水;每天注射1次,连续注射7 d。术后2 周、4 周分别行X 线摄片,并采集各组大鼠股动脉血液标本后,采用颈椎离断法处死大鼠。取各组大鼠左胫骨骨痂标本,采用酶联免疫吸附试验(ELISA)检测碱性磷酸酶(ALP)含量;将骨痂组织制成病理切片,行HE染色,观察组织学特点;应用多功能真彩色细胞图象分析管理系统计算切片中骨组织的骨小梁表面成骨细胞指数(IOB)、骨小梁宽度(TW)、骨小梁面积百分比(TV);采用蛋白芯片技术检测大鼠血清中骨形成蛋白-2(BMP-2)、血管内皮生长因子(VEGF)、胰岛素样生长因子-1(IGF-1)的含量。结果 (1)术后2周、4周X线摄片:NGF、BFGF、NGF+BFGF三组大鼠骨折愈合均较对照组快,以NGF+BFGF组愈合最快。(2)ELISA检测:对照组、NGF组、BFGF组、NGF+BFGF组术后2周骨痂组织中ALP的含量分别为(110.02±1.92)、(140.87±2.22)、(136.12±1.23)、(187.44±0.90)ng/mL,术后4周骨痂组织中ALP的含量分别为(91.23±1.47)、(106.62±1.64)、(104.83±1.05)、(130.59±1.18)ng/mL;各观察时点4组间比较,NGF+BFGF组含量最高,组间两两比较差异均有统计学意义(P值均＜0.05)。(3)组织学观察:不同时间点上NGF、BFGF、NGF+BFGF三组大鼠在骨痂的生长、骨小梁形成均较对照组明显,且NGF+BFGF组优于其他组。骨小梁形态学指标测量显示,不同时间点4组间比较,对照组、NGF组、BFGF组、NGF+BFGF组大鼠骨痂内骨小梁IOB、TW、TV均呈上升趋势,NGF+BFGF组最高;组间两两比较,除NGF组与BFGF组各指标差异均无统计学意义(P值均＞0.05),其他指标组间差异均有统计学意义(P值均＜0.05)。(4)蛋白芯片检测:不同时间点4组间比较,除VEGF含量在术后4周时差异无统计学意义(P＞0.05),VEGF术后2周及BMP-2、IGF-1术后2周、4周时,NGF组、BFGF组、NGF+BFGF组均高于对照组,NGF+BFGF组含量最高,组间两两比较,差异均有统计学意义(F=198.285、368.060、2006.017、33.332、292.643,P值均＜0.05)。结论NGF及BFGF均能促进大鼠胫骨骨折愈合,且两者联合应用有协同作用。其机制可能与能够促进骨折愈合过程中VEGF、BMP-2、IGF-1的表达有关。     

联合应用上颌前方牵引与快速扩大对恒牙早期安氏Ⅲ类错颌骨硬组织的作用

目的研究联合应用上颌前方牵引与快速扩大对恒牙早期安氏Ⅲ类错颌骨硬组织改建的作用.方法以T2-T1代表自然生长6个月颌骨的改变,T3-T2代表应用联合前方牵引与快速扩大6个月颌骨的改变,比较这两种变化的差异.对23例恒牙早期患者应用联合法治疗前后硬组织的改变进行了分析.结果自然状态下,硬组织有前下生长趋势,应用联合法后,上颌骨S-A、Pt-A、PNS-A显著增大,其增大量PNS-A>Pt-A>S-A;下颌骨Pg、Me明显后移,Wits值显著增大了4.5mm.结论恒牙早期安氏Ⅲ类错联合应用前方牵引与快速扩大,能够使上颌骨前后径增大,上颌骨前移;下颌骨向后移位和轻度向下移位.