载特立帕肽聚乳酸乙醇酸磷酸钙骨水泥复合组织工程骨材料学特性及生物相容性研究

目的 制备载特立帕肽聚乳酸乙醇酸磷酸钙骨水泥（PTH-PLGA-CPC）复合组织工程骨并研究其材料学特性及生物相容性。方法 采用复乳溶剂蒸发法制备载特立帕肽聚乳酸乙醇酸（PTH-PLGA）微粒,观察外观、孔径并计算孔隙率,检测特立帕肽（甲状旁腺激素、PTH）的载药量及缓释比例。制备PTH-PLGACPC复合组织工程骨并计算孔径大小。将兔骨髓间充质干细胞接种于PTH-PLGA-CPC表面,观察细胞形态、CCK-8法检测细胞的增殖情况、硝基苯磷酸酯二钠试剂检测细胞碱性磷酸酶活性。结果 PTH-PLGA微球表面光滑,孔径均值为216+94μm,载药率约76.4%。PTH-PLGA-CPC组织工程骨呈多孔网状结构,孔径率均值为62.4+5.6%,孔径大小均值为212+76μm,与PLGA-CPC抗压强度无差异。接种于PTH-PLGA-CPC表面的兔骨间充质干细胞形态正常,细胞计数及碱性磷酸酶活性明显高于PLGA-CPC组及空白对照组。结论 PTH-PLGACPC复合组织工程骨呈多孔网状结构,具有合适的孔径大小及孔径率,并且在体外细胞试验中具有良好的生物相容性及成骨活性。     

间歇性高糖环境对小鼠颅骨成骨细胞的影响

目的:观察间歇性高糖环境对小鼠颅骨成骨细胞形态、增殖及功能蛋白表达的影响。方法:将体外培养原代小鼠颅骨成骨细胞分为3组:正常糖浓度组(5.5mmol/L GLU)、持续性高糖组(25mmol/L GLU)、间歇性高糖组(5.5mmol/L GLU²5mmol/L GLU),干预3天后,MTT法检测细胞增殖抑制率;干预3周后,比色法和放射免疫法(RIA)分别检测培养上清液中碱性磷酸酶(ALP)和骨钙素(OCN)水平的变化。结果:(1)在相同干预时间点,与正常糖浓度组相比,高糖组细胞增殖受抑制,其中间歇性高糖组细胞受抑制更显著(P<0.05)。(2)在相同干预时间点,高糖组成骨细胞的ALP、OCN均较正常糖浓度组下降,其中间歇性高糖组下降更显著;(3)随干预时间增加,高糖组成骨细胞的ALP、OCN均较正常糖浓度组下降(P<0.05)。结论:高糖环境可抑制成骨细胞的增殖、诱发细胞凋亡,并导致功能蛋白ALP、OCN下降,且这一损害作用在间歇性高糖环境更为显著。     

乳腺小叶增生临床治疗经验总结

目的观察对比微波热疗配合口服乳康片与单纯口服乳康片治疗乳腺小叶增生的疗效方法 :36 3例乳腺小叶增生随机分为微波热疗配合口服乳康片 192例和口服乳康片 171例二组疗效的观察。结果 :综合治疗组 (微波热疗 +口服乳康片 )的痊愈率 34 .9% ,单纯中药治疗组 (口服乳康片 )的痊愈率 12 .9% ,两组比较有显著性差异P〈0 .0 5;综合治疗组有效率 94 .3% ,单纯中药治疗组有效率 4 0 .4 % ,两组比较有显著性差异P〈0 .0 5。结论 :微波热疗口服乳康片配合疗效明显优于单纯口服中成药乳康片     

209例肺癌患者全身骨显像临床分析

目的:探讨骨全身显像结果与不同临床分期及病理类型肺癌患者的关系。方法:对209例经病理证实的肺癌患者行常规全身骨显像。其结果与患者临床分期及病理类对照。结果:Ⅰ-Ⅱ期患者骨转移发生率0例(0%),Ⅲ期患者8例(9.5%),IV期患者105例(89.7%),总转移率为54.1%。其中鳞状细胞癌(34/92),腺癌(33/60),大细胞癌(26/33),小细胞癌(21/34);多发转移(3处以上)63例,少发转移(2-3处)37例,单发13例。结论:Ⅲ-Ⅳ期肺癌患者应实施常规骨显像,以免漏诊骨转移。     

二甲双胍对多囊卵巢综合征患者疗效、代谢特征及激素水平的改善作用分析

目的 探讨应用二甲双胍对多囊卵巢综合征患者进行治疗的效果;方法 将甘肃省兰州市安宁区人民医院2019年3月至2020年3月作为研究时段,将该时段录入数据库资料登记有效的确诊为多囊卵巢综合征不孕患者22名作为研究对象,按照随机均分法,分为对照组与实验组,组内样本量设置为11。对照组患者选择炔雌醇环丙孕酮片进行治疗,实验组患者则在此基础上增加二甲双胍进行用药,对比两组患者治疗后睾酮、垂体分泌卵泡雌激素以及多囊卵巢综合征不孕治疗总有效率;结果 在实验结果中发现,相较于对照组来说,实验组患者的治疗总有效率明显更优,数据对比分析差异显著（P<0.05）,而在治疗完成后对两组患者的各项指标进行分析,发现实验组患者激素水平明显优于对照组,组间差异显著（P<0.05）;结论 选择二甲双胍对多囊卵巢综合征患者进行治疗,效果良好。     

血清CA125和HE4在卵巢肿瘤良恶性及分期诊断中的意义

目的：回顾性分析血清CA125和HE4在卵巢肿瘤中的表达情况,探讨其在卵巢良恶性肿瘤中及不同分期的卵巢恶性肿瘤中的表达差异。方法：统计分析2012年1月～2013年2月在重医附二院手术治疗的85例卵巢肿瘤患者血清的CA125和HE4的检测结果,计算CA125和HE4在卵巢良恶性肿瘤和不同分期肿瘤中的表达情况及表达阳性率。结果：卵巢恶性肿瘤组血清CA125和HE4水平均明显高于卵巢良性疾病组,差异有统计学意义(＜0.01)。CA125阳性率卵巢恶性肿瘤Ⅰ期～Ⅱ期(57.1%)、Ⅲ期～Ⅳ期(100%);HE4阳性率卵巢恶性肿瘤Ⅰ～Ⅱ期(0%)、Ⅲ～Ⅳ期(90.48%)。结论：CA125和HE4在卵巢良恶性肿瘤和不同分期的卵巢癌血清中的表达有显著差异,具有临床诊断价值。     

大补阴丸对甲亢大鼠FT_3、FT_4、T_3、T_4、TSH影响的实验研究

目的观察大补阴丸对甲亢大鼠模型的治疗作用。方法用优甲乐灌服制作大鼠甲亢模型,观察该方对模型大鼠的影响。将大鼠随机分成6组:正常对照组、甲亢模型组、西药对照组、大补阴丸低剂量组、大补阴丸中剂量组、大补阴丸高剂量组,21d后放免法测定血清游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)、三碘甲腺原氨酸(T3)、甲状腺素(T4)、促甲状腺激素(TSH)含量。结果大补阴丸能降低甲亢大鼠血清FT3、FT4、T3、T4含量,提高血清TSH。结论大补阴丸能够显著改善甲状腺激素水平。     

卵巢过度刺激综合征的临床护理

卵巢过度刺激综合征 (ＯＨＳＳ)是不孕患者应用超促排卵药物后所致的医源性疾病。其主要病理特征是 :高雌激素血症 ,全身毛细血管通透性增加 ,尤其是双卵巢组织 ,从而导致体液渗出 ,血液浓缩 ,肾血流量减少 ,水电解质平衡失调 ,少尿 ,酸中毒 ,严重可危及生命 ,现将临床护理体会介绍如下 :1.临床资料 :本文收集ＯＨＳＳ 2 9例 ,其中重度 7例 ,中度 16例 ,轻度 6例 ,年龄 2 4 - 4 1岁 ,均由多种原因引起不孕 ,接受达必佳 ,果纳芬 ,绝经期尿促性腺激素 (ＨＭＧ)联合绒毛膜促性腺激素 (ＨＣＧ)超促排卵治疗 ,出现不同程度下腹胀痛、胃部不适、尿…     

中医辨证治疗胃癌癌前病变的临床观察

目的观察中医辨证治疗胃癌癌前病变的临床疗效。方法将70例胃癌癌前病变患者随机分为两组,治疗组36例服用中药汤剂治疗,对照组34例采取胃复春片治疗;均以三月为一疗程,结果:治疗组的证候疗效、胃镜疗效、病理疗效的总有效率分别94.44%、61.11%、63.89%,对照组胃复春片证候疗效、胃镜疗效、病理疗效的总有效率分别64.71%、32.25%、29.41%,两组总有效率比较有统计学意义(P<0.01)。结论中医辨证治疗胃癌癌前病变效果明显优于胃复春片。     

小骨窗血肿清除术与微创穿刺血肿引流术治疗高血压脑出血患者的临床效果比较

目的 探讨并分析小骨窗血肿清除术与微创穿刺血肿引流术两种治疗方式对高血压脑出血患者的临床治疗效果。方法 选取我院2017年1月到2022年3月期间的60例高血压脑出血患者为本次研究对象,采取计算机表法对并其进行研究,分为研究组和对照组,每组30例患者,研究组高血压脑出血患者采取微创穿刺血肿引流术治疗方式,对照组患者采用常规小骨窗血肿清除术方式。结果 研究组高血压脑出血患者手术情况,主要包括术中出血量、手术时间以及术后住院时间明显少于对照组,研究组高血压脑出血患者的临床治疗总有效率（90.00%）明显高于对照组（66.67%）。研究组高血压脑出血患者的并发症发生情况,主要包括肺部感染、再出血以及颅内感染等情况的总发生率（6.67%）明显低于对照组（26.67%）,差异有统计学意义（P<0.05）。结论 将小骨窗血肿清除术与微创穿刺血肿引流术应用于高血压脑出血患者中,二者治疗方式均有效果,但是微创穿刺血肿引流术治疗效果更为显著,对患者的创伤较小,明显缩短患者的治疗时间,有效降低并发症的发生率,值得在目前临床中推广应用。     

漂移型线性规划理论及应用

到目前为止,有关灰色线性规划问题有不少研究,如灰色预测型线性规划^[1～6]灰色区间型线性规划^[7]等．本文在文献^[1～7]的基础上,针对漂移型线性规划问题,运用参数线性规划理论与方法,对其满意解及其性质等进行探研,并提出了一些新的结论,不仅为漂移型线性规划作了一些理论讨论,而且还以应用实例给予示范．     

Cancer risk estimation for mixtures of coal tars and benzo(a)pyrene.

Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk < 1.03 x 10(-4) (ppm coal tar in total diet) + 240 x 10(-4) (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk < 2.55 x 10(-4) (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 x 10(-3) per microgram per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 x 10(-3) per microgram per kg body weight per day listed in the U.S. EPA Integrated Risk Information System.     

Cancer Risk Estimation for Mixtures of Coal Tars

Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk < 1.03 × 10⁻⁴ (ppm coal tar in total diet) + 240 × 10⁻⁴ (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk < 2.55 × 10⁻⁴ (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 × 10⁻³ per μg per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 × 10⁻³ per μg per kg body weight per day listed in the U.S. EPA Integrated Risk Information System.     

On Motzkin–Straus type results for non-uniform hypergraphs

Recently, some extensions of Motzkin–Straus theorems were proved for non-uniform hypergraphs whose edges contain 1 or r vertices in Gu et al. (J Comb Optim 31:223–238, 2016), Peng et al. (Discret Appl Math 200:170–175, 2016a), where r is a given integer. It would be interesting if similar results hold for other non-uniform hypergraphs. In this paper, we establish some Motzkin–Straus type results for general non-uniform hypergraphs. In particular, we obtain some Motzkin–Straus type results in terms of the Lagrangian of non-uniform hypergraphs when there exist some edges consisting of 2 vertices in the given hypergraphs. The presented results unify some known Motzkin–Straus type results for both uniform and non-uniform hypergraphs and also provide solutions to a class of polynomial optimization problems over the standard simplex in Euclidean space.     

新时代防控金融风险跨市场交叉网络传染机制研究

文章基于习近平新时代中国特色社会主义金融思想与大数据时代背景,探讨了防控金融风险跨市场交叉网络传染机制。通过模型的理论推演及数值仿真模拟分析,研究结果表明：防控金融风险跨市场交叉传染主要取决于R₀,其值越大,金融风险跨市场交叉传染越容易形成蔓延趋势;金融风险在各个金融子市场之间交叉传染蔓延趋势主要取决于β、δ、α、μ、γ等因素;仅采取事前防御措施或事后防控化解的金融风险防范措施都将缺乏效率,应从事前防御与事后化解两个层面统筹采取金融风险防范措施以提升防范金融风险跨市场交叉传染能力;在此基础上从三个层面提出了防控金融风险跨市场交叉网络传染机制,为构建金融风险救助机制预案以阻隔金融风险在各个金融子市场之间进一步交叉传染蔓延,实现新时代增强金融风险跨市场交叉传染防范与控制能力,更好的防范与化解系统性金融风险以助力打好防范化解重大风险攻坚战、维护国家金融安全的目标提供一定的借鉴与参考。     

Benchmark Dose Risk Assessment for Formaldehyde Using Airflow Modeling and a Single-Compartment, DNA-Protein Cross-Link Dosimetry Model to Estimate Human Equivalent Doses

Formaldehyde induced squamous-cell carcinomas in the nasal passages of F344 rats in two inhalation bioassays at exposure levels of 6 ppm and above. Increases in rates of cell proliferation were measured by T. M. Monticello and colleagues at exposure levels of 0.7 ppm and above in the same tissues from which tumors arose. A risk assessment for formaldehyde was conducted at the CIIT Centers for Health Research, in collaboration with investigators from Toxicological Excellence in Risk Assessment (TERA) and the U.S. Environmental Protection Agency (U.S. EPA) in 1999. Two methods for dose-response assessment were used: a full biologically based modeling approach and a statistically oriented analysis by benchmark dose (BMD) method. This article presents the later approach, the purpose of which is to combine BMD and pharmacokinetic modeling to estimate human cancer risks from formaldehyde exposure. BMD analysis was used to identify points of departure (exposure levels) for low-dose extrapolation in rats for both tumor and the cell proliferation endpoints. The benchmark concentrations for induced cell proliferation were lower than for tumors. These concentrations were extrapolated to humans using two mechanistic models. One model used computational fluid dynamics (CFD) alone to determine rates of delivery of inhaled formaldehyde to the nasal lining. The second model combined the CFD method with a pharmacokinetic model to predict tissue dose with formaldehyde-induced DNA-protein cross-links (DPX) as a dose metric. Both extrapolation methods gave similar results, and the predicted cancer risk in humans at low exposure levels was found to be similar to that from a risk assessment conducted by the U.S. EPA in 1991. Use of the mechanistically based extrapolation models lends greater certainty to these risk estimates than previous approaches and also identifies the uncertainty in the measured dose-response relationship for cell proliferation at low exposure levels, the dose-response relationship for DPX in monkeys, and the choice between linear and nonlinear methods of extrapolation as key remaining sources of uncertainty.     

Risk Assessment of Laboratory Rats and Mice Chronically Exposed to Formaldehyde Vapors

Experimental data from the Chemical Industry Institute of Toxicology (CIIT) are used to estimate the risk of squamous cell carcinoma of the nasal cavity in Fischer 344 (F344) rats over a range of ambient air concentrations of formaldehyde that includes current exposure guidelines for the workplace and home. These values are presented as a best estimate envelope obtained from five mathematical dose-response formulation. The response of Sprague-Dawley (SD) rats dosed at 15 ppm in a separate study at New York University is consistent with the predicted lifetime response for F344 rats at a slightly lower concentration (13-14 ppm). A dose-related mortality effect beyond what is attributable to the occurrence of nasal carcinomas is found in F344 rats at all CIIT exposure levels (2, 6, and 15 ppm). There is no evidence of a mortality effect in B6C3F1 mice of the CIIT study, and data for SD rats of the NYU experiment are inconclusive. In the CIIT study, rats exposed to 15 ppm exhibited a high incidence of nasal cavity squamous cell carcinomas and polypoid adenomas. Polypoid adenomas were also observed with increased incidences at 2 ppm and 6 ppm. Statistical comparisons with matched controls, and the low historical rate of spontaneous occurrence both suggest that polypoid adenomas may be a risk to F344 rats at exposure levels below the current Occupational Safety and Health Administration (OSHA) standard of 3 ppm. Squamous cell carcinomas were observed in two mice exposed to 15 ppm. This finding may be biologically significant since this tumor is rare and has not been previously reported in 4932 untreated B6C3F1 mice from recent National Toxicology Program (NTP) feeding studies.     

知识的分类及其管理

知识管理是一个寻求数据和信息处理能力与员工的创造和革新能力协作组合的组织过程,其目的是为了提高企业应付外界环境变化的适应、生存和竞争能力。但是,由于知识具有多样性、复杂性和动态性等特征,试图通过一种模式来实施对知识的有效管理是不现实的,也是不可能的。企业要有效地管理知识,应在对企业知识进行分类的基础上,根据企业的经营目标,采取相应的管理策略,因此归纳了5种分类方法显性知识和隐性知识、内部知识和外部知识、个人知识和组织知识、实体知识和过程知识、核心知识和非核心知识,并时各种分类提出了相应的管理策略。     

含有图结构约束的稀疏最小方差资产组合模型

图结构是广泛用于描述生物学信息的一个重要方法。考虑到不同资产之间的相互影响作用,引入图结构来描述高维资产之间包含的信息,建立了一种基于图结构约束的最小方差资产组合模型,并且提供了一种有效的坐标下降优化算法。研究结果表明,基于图结构约束的资产组合模型在收益率、波动率和变量选取方面优于传统的资产组合模型,该模型对金融机构的投资决策有重要的实际意义。     

Evaluation of False Positive and False Negative Outcomes in NTP Long-Term Rodent Carcinogenicity Studies

The decision-making process used by the National Toxicology Program (NTP) in its evaluation of long-term rodent carcinogenicity studies was investigated to determine whether or not this procedure resulted in an excessive number of false positive or false negative outcomes. All site-specific tumor incidences that were found to be significantly ( p < 0.05) increased either by a trend test or by pairwise comparisons of each dosed group against the controls in 218 NTP 2-year studies with Fischer 344 rats and/or B6C3F1 mice were tabulated and compared to the number of statistically significant tumor increases expected to occur by chance. Our evaluation suggests that false positive rates are fairly low in NTP long-term studies. Assessing false negative rates is more difficult because of the limited sensitivity of the bioassay for detecting subtle carcinogenic effects. Moreover, reduced body weights frequently occur in dosed animals, and the positive correlation between the incidences of certain site-specific tumors and body weight may mask the detection of carcinogenic effects. Despite these difficulties, our analysis did identify one tumor showing evidence of false negative outcomes: interstitial cell tumors of the testis in male Fischer 344 (F344) rats. This tumor showed considerably more significant ( p > 0.05) increased incidences than expected by chance, yet none were considered to be chemically-related. However, the biological significance of interstitial cell tumor increases in F344 rats is uncertain because of the high background rate of neoplasia (>90%) for this target site.