DWI及动态增强MRI鉴别乳腺病变的对比研究

目的：对比研究磁共振弥散加权成像（DWI）和动态增强磁共振成像（DCE-MRI）诊断乳腺病变的敏感性和特异性,为临床诊断提供数据支持。方法回顾分析2010年8月～2013年8月收治的乳腺病变患者84例。所有患者均进行乳腺DCE-MRI和DWI检查。观察记录DWI图像和表现扩散系数（ADC）,DCE-MRI的早期强化率（slope）和增强比率（SER）等数据,判断乳腺病变的良恶性。结果 ADC、SER和slope的ROC曲线下面积分别为0.92、0.82、0.86。DWI和DCE-MRI诊断乳腺病变良恶性的敏感度为92.34%和86.98%,特异度为84.34%和86.36%。良性病变与恶性病变间的ADC、SER、slope值有显著性差异（P＜0.05）。结论在鉴别乳腺病变良恶性方面,DWI稍稍优于DCE-MRI。两者均有一定的临床应用价值。     

动态增强磁共振成像结合表观弥散系数在卵巢病变中的诊断效果分析

目的　探讨动态增强磁共振成像（DCE-MRI）定量参数结合表观弥散系数（ADC）在卵巢病变中的诊断价值。方法　回顾性分析2014 年5 月～2017 年1 月于我院就诊的142 例卵巢病变患者临床资料，根据病理诊断结果将其分为卵巢恶性肿瘤组和卵巢良性肿瘤组。比较两组患者DCE-MRI 定量参数［容量转移常数（Ktrans）、速率常数（Kep）、血管外细胞外容积分数（Ve）］及扩散加权成像（DWI）ADC 值检测结果的差异，经受试者工作曲线（ROC 曲线）分析DCE-MRI 定量参数及ADC 值在卵巢病变良恶性鉴别中的诊断效能。结果　病理检查确诊卵巢良性肿瘤88 例（92 个肿块），卵巢恶性肿瘤54 例（60个肿块）。卵巢恶性肿瘤组Ktrans、Kep、Ve 等DCE-MRI 定量参数值均明显高于卵巢良性肿瘤组，ADC 值则明显低于卵巢良性肿瘤组，差异均有统计学意义（P<0.05）。ROC 曲线显示，Ktrans、Kep 值在卵巢病变良恶性鉴别诊断中特异度高但敏感度较低，Ve、ADC 值则敏感度高、特异度低，差异有统计学意义（P<0.05）。结论　DCE-MRI 和DWI 检查在卵巢病变的良恶性鉴别诊断中均有较高应用价值，临床可将其结合使用，为治疗方案的确定提供依据。     

磁共振扩散加权成像联合时间-信号强度曲线在诊断乳腺癌中的应用价值

目的 探讨磁共振扩散加权成像(DWI)联合时间-信号强度曲线(TIC)在诊断乳腺癌中的应用价值.方法 28例乳腺癌患者和25例乳腺良性病变患者均行DWI及磁共振动态增强(DCE-MRI)检查.比较乳腺良性病变和乳腺癌MRI动态增强的形态学特征,TIC曲线形态及分布,ADC值,两者联合诊断和单一诊断的敏感性、特异性和准确性.结果 乳腺良性病变MRI动态增强的形态主要以类圆形为主(76.0％),边缘以光滑(72.0％)为主,乳腺癌的形态主要以分叶形为主(60.7％),边缘以毛刺征(60.7％)为主,两组比较差异均有统计学意义(均P＜ 0.05);乳腺良性病变TIC曲线形态以Ⅰ型(68.0％)为主,恶性病变以Ⅲ型(78.6％)为主,两组比较差异有统计学意义(P＜0.05);78.6％乳腺癌ADC值≤1.22×10-3 mm2/s,80.0％乳腺良性病变ADC值＞1.22×10-3 mm2/s,两组比较差异有统计学意义(P＜0.05);两者联合诊断乳腺良恶性病变的敏感性、特异性及准确性均明显高于磁共振动态增强、扩散加权成像单一诊断(均P＜ 0.05).结论 DWI联合TIC诊断乳腺癌患者具有较高的临床价值.     

3.0T MR弥散加权成像定量分析表观弥散系数对乳腺良恶性病变的诊断

目的 探讨3.0T MR弥散加权成像(DWI)定量分析表观弥散系数(ADC)对乳腺良恶性病变的诊断价值.方法 对经病理证实的50例乳腺病变57个病灶行MR弥散加权成像及动态增强扫描(DCE-MRI),绘制病灶感兴趣区(ROI)时间-信号强度曲线(TIC),分析曲线类型、测量病灶ADC值.结果 在b取50 s/mm2和800 s/mm2情况下,本组良性病变ADC值为(1.483±0.358)×10-3mm2/s,明显大于恶性病变的(0.952±0.148)×10-3 mm2/s(P＜0.05).经受试者工作曲线(ROC)分析得出良恶性病变ADC诊断阈值为1.219×10-3mm2/s.该值对乳腺恶性病变诊断的敏感性及特异性分别为90.6%和84.0%.DCE-MRI对乳腺恶性病变诊断的敏感性和特异性分别为87.5%和80.8%.ADC值与DCE-MRI结合诊断的敏感性和特异性提高为93.8%和88.0%.ADC值与DCE-MRI对乳腺恶性病变诊断的敏感性和特异性差异无统计学意义(P＞0.05).结论 3.0TMRI DWI定量分析ADC值对于乳腺病变的诊断及鉴别诊断有重要价值.     

DCE-MRI+DWI检查在进展期胃癌患者诊断中的应用

目的：探讨磁共振动态增强扫描(DCE-MRI)联合弥散加权成像(DWI)在进展期胃癌(AGC)患者诊断中的应用价值。方法：选取我院141例疑似AGC患者作为研究对象,均行DCE-MRI检查、DWI检查,以手术病理检查结果为“金标准”,比较不同诊断结果患者DCE-MRI参数、DWI信号强度值及表观弥散系数(ACD)值,以及DCE-MRI、DWI联合检查诊断结果、诊断效能。结果：AGC患者血管外细胞外间隙体积百分数(Ve)、转运常数(Ktrans)、速率常数(Kep)较胃部良性疾病高(P<0.05);AGC患者ADC值以及b=400、800s/mm2时信号强度值较胃部良性疾病患者低(P<0.05);141例疑似AGC患者,经手术病理结果显示104例确诊为AGC;DCE-MRI联合DWI检查AGC患者诊断准确度90.07%、灵敏度91.35%高于DCE-MRI 78.85%、78.01%、DWI 76.92%、77.31%单独检查(P<0.05)。结论：DCE-MRI+DWI检查应用于AGC患者可获得较高诊断准确度、灵敏度,为临床诊治AGC提供充分影像学依据,值得临床推广应...     

DCE-MRI联合DWI对原发性肝癌患者阳性检出率的影响

目的分析磁共振动态增强扫描(DCE-MRI)联合弥散加权成像(DWI)对原发性肝癌患者阳性检出率的临床价值。方法 70例原发性肝癌患者,分析并比较DCE-MRI、DWI及DCE-MRI联合DWI检查的影像学表现以及阳性符合率。结果在DCE-MRI、DWI以及DCE-MRI联合DWI动态扫描中,分别有47、51、69例患者检查显示病变部位信号强度显著高于周围正常组织,均在门脉期和延迟期表现为低信号或者为等信号。DCE-MRI检查小肝癌型、结节型、块状型阳性符合率分别为68.18%、69.57%、64.00%, DWI检查小肝癌型、结节型、块状型阳性符合率分别为77.27%、77.27%、72.00%,DCE-MRI联合DWI检查小肝癌型、结节型、块状型阳性符合率分别为100.00%、100.00%、96.00%。DCE-MRI联合DWI检查小肝癌型、结节型、块状型三种原发性肝癌阳性符合率均高于DCE-MRI、DWI单独检查,差异有统计学意义(P<0.05)。结论 DCE-MRI联合DWI检查应用于原发性肝癌患者诊断中可提高病变部位的阳性检出率,两种检查方法联合使用对于肝脏的诊断价值较高。     

磁共振全身扩散加权成像对肺癌的临床分期和疗效评估价值

目的：探讨磁共振全身扩散加权成像（ DWI）在肺癌的临床分期及疗效评估中的价值。方法对该院2012年1月至2014年1月收治的68例经病理组织学确诊的肺癌患者采用DWI检查,比较不同肺癌病理类型、分化程度、不同的T分期及N分期患者的表观扩散系数（ ADC）值差异;并对肺癌患者采用吉西他滨联合顺铂进行化疗,并比较治疗前1周和治疗后3个月所有肺癌患者的ADC值变化情况。结果不同组织学类型的肺癌ADC值之间存在显著的统计学差异（P＜0．05）,三组间两两比较差异也具有统计学意义（P＜0．05）,腺癌ADC值（1．338±0．246）×10－3 mm2· S－1明显高于鳞癌和小细胞癌。不同分化程度的肺癌ADC值差异具有统计学意义（P＜0．05）,高分化组肺癌ADC值明显高于中分化、低分化组,中分化组和低分化组差异不具有统计学意义（P＞0．05）。肺癌不同T分期患者的ADC值差异具有显著统计学意义（P＜0．05）,组间两两比较仅T1分期ADC值明显高于其它分期且具有统计学意义（ P＜0．05）。肺癌不同N分期患者的ADC值差异具有显著统计学意义（P＜0．05）,组间两两比较仅N3分期ADC值明显低于于其他分期且具有统计学意义（P＜0．05）。治疗有效组的ADC值明显升高且差异具有统计学意义（P＜0．05）;治疗3个月后两组ADC值差异显著,有效组的ADC为（1．464±0．317）×10－3mm2· S－1明显高于无效组的（1．315±0．284）×10－3mm2· S－1且差异具有统计学意义（P＜0．05）。结论 DWI在肺癌的诊断及病理类型、分期中具有一定的临床价值,对治疗效果能够进行有效的临床评价。     

磁共振DWI序列在肺部良恶性病变鉴别诊断中的应用

目的：评价1.5超导磁共振弥散成像（DWI）序列在肺部良恶性结节或肿块诊断、治疗后评价中的应用价值。方法对24个肺部疾病患者进行DWI检查,分析肺癌、肺良性病变、肺癌放疗后肿块复发、放射性肺炎ADC值差异。结果良性病变与肺恶性病变在分子扩散方面存在差异, DWI信号差异及ADC值是鉴别肺部良、恶性病变的有效数据。结论 DWI对肺癌、肺良性病变、肺癌放疗后肿块复发、放射性肺炎诊断具有价值,比较常规磁共振检查更有优势。     

多模态磁共振成像在乳腺癌诊断中的应用价值

目的 应用多模态MRI包括弥散加权成像和动态增强扫描（DCE-MRI）对乳腺癌患者的检测，分析其MRI相关影像特征，探讨其对该病诊断的准确性。方法 回顾分析2012年1月至2016年8月于安徽医科大学第一附属医院术前行MRI检查和术后病理或穿刺活检证实的16例乳腺癌女性患者多模态MRI数据资料，统计分析表观弥散系数（ADC）、相对表观弥散系数（rADC）值及动态时间信号强度曲线图像（TIC）。结果 16例患者MRI显示病灶多见分叶（75.00%）、毛刺（75.00%），边界不清（81.25%）。ADC值为（0.92±0.19）×10^-3 mm²/s，rADC为（0.56±0.13）×10^-3 mm²/s。TIC：Ⅱ型4例（25.00%），Ⅲ型12例（75.00%），无符合Ⅰ型的病例。结论 多模态MRI用于乳腺癌的检查，结合病变形态学改变、DCE-MRI的TIC曲线形态和ADC值，可以提高乳腺癌的诊断正确率。     

MRI联合扩散加权成像在宫颈癌分期诊断中的应用效果评价

目的 探讨MRI联合扩散加权成像(DWI)在宫颈癌分期诊断中的应用效果。方法 将2018年3月～2019年9月我院收治的65例宫颈癌患者作为宫颈癌组,选取同时期65名正常宫颈人群作为正常组,分别对其进行常规MRI平扫及扩散加权成像(DWI)联合动态增强磁共振成像(DCE-MRI)检测,对两种检查方式的准确率情况、正常宫颈及宫颈癌的MRI表现、DWI及ADC值、DCE-MRI各参数的分析情况进行观察。结果 DCE-MRI结合DWI在宫颈癌分期中的准确率明显高于常规MRI诊断的准确率;正常子宫颈的ADC值明显高于宫颈癌ADC值;随着分级程度的不断升高,ADC值不断降低,差异有统计学意义(P 0.05);62例患者MRI增强扫描的时间-信号曲线表现为平台型,3例患者表现为流入型;DCE-MRI定量参数K_(trans)、V_e、K_(ep)值随着宫颈癌分期的升高而变大,差异有统计学意义(P 0.05)。结论 MRI联合扩散加权成像在宫颈癌分期诊断中的应用具有显著的临床效果。     

Affective and Anxiety Disorders and Alcohol and Drug Dependence:

Depression and anxiety frequently coexist in patients with substance use disorders. This clinically-oriented article examiens the relationship between these conditions and emphasizes data showing that substances of abuse can cause signs and symptoms of both depression and anxiety. These substance-related syndromes appear to have a different course and prognosis than uncomplicated, independent anxiety and major depressive disorders, and clinicians should consider the role of alcohol and other drugs in all patients presenting with these complaints. The authors will also outline an approach for diagnosing and managing patients with the combination of a substance use and depressive or anxiety disorder.     

Synthesis and anti-nociceptive and anti-inflammatory effects of gaultherin and its analogs

The synthesis of gaultherin (1) and its analogs was carried out to provide 11 glycosides under phase-transfer catalytic conditions. The activities of all synthesized compounds were evaluated by nitric oxide production inhibitory assay in vitro. Methyl 2-O-(4-O-β-d-galactopyranosyl)-β-d-glucopyranosylbenzoate (5f) showed significantly anti-nociceptive and anti-inflammatory effects by the evaluation in vivo. Structure–activity relationships within these compounds were discussed.     

Modelling and simulation of variability and uncertainty in toxicokinetics and pharmacokinetics

Two important methodological issues within the framework of the variability and uncertainty analysis of toxicokinetic and pharmacokinetic systems are discussed: (i) modelling and simulation of the existing physiologic variability in a population; and (ii) modelling and simulation of variability and uncertainty when there is insufficient or not well defined (e.g. small sample, semiquantitative, qualitative and vague) information available. Physiologically based pharmacokinetic models are especially suited for separating and characterising the physiologic variability from the overall variability and uncertainty in the system. Monte Carlo sampling should draw from multivariate distributions, which reflect all levels of existing dependencies in the intact organism. The population characteristics should be taken into account. A fuzzy simulation approach is proposed to model variability and uncertainty when there is semiquantitative, qualitative and vague information about the model parameters and their statistical distributions cannot be defined reliably.     

成骨细胞的功能与损伤和骨质疏松的防治

骨质疏松是一种全身性骨骼疾病,导致骨折风险增加。成人的骨量通过破骨细胞的骨吸收和成骨细胞的骨形成作用来维持动态平衡,治疗骨质疏松症的理想策略是抑制破骨细胞的骨吸收和/或增强成骨细胞的骨形成功能。目前针对保护成骨细胞及增强其功能的骨质疏松疗法相对较少。因此,本文针对成骨细胞相关功能蛋白、各种细胞损伤机制（内质网应激、氧化应激、机械过载、微小RNA和长链非编码RNA的影响等）及骨质疏松的治疗与预防作一综述,以期为针对增强成骨细胞功能的骨质疏松治疗策略提供新思路。     

益生菌与肿瘤防治

益生菌广泛存在于自然界中,通过维持宿主体内菌群平衡、影响肠屏障功能和调节免疫应答等作用,提高宿主健康水平,被公认为"肠道健康卫士".一些益生菌可以增强机体的免疫功能,抑制致癌物质,影响肿瘤细胞的基因表达,对肿瘤具有拮抗作用.大量研究表明,益生菌在未来的肿瘤防治中有很好的应用和发展前景.     

Self-stimulation and amphetamine: Tolerance to d and l isomers and cross tolerance to cocaine and methylphenidate

The effects of the d and l isomers of amphetamine on self-stimulation responding were tested following acute and chronic administration. Tolerance and post-drug depression of responding occurred in tests with both isomers, indicating no role for p-hydroxynorephedrine (PHN) which is one of the metabolites of d-amphetamine. In the second experiment, d-amphetamine, methylphenidate and cocaine all produced quantitatively and qualitatively similar effects on self-stimulation responding following acute administration. Following chronic administration of d-amphetamine, animals showed tolerance to all three drugs, indicating cross-tolerance among them. These data are consistent with an hypothesis that tolerance and post-drug depression following chronic amphetamine treatment are the result of decreases in postsynaptic receptor sensitivity, which would lead to a decreased effectiveness of all three drugs, regardless of their pre-synaptic mechanisms.     

Acamprosate and naltrexone treatment effects on ethanol and sucrose seeking and intake in ethanol-dependent and nondependent rats

Rationale  Two pharmacotherapies are approved for treating alcohol craving (acamprosate and naltrexone), but both have shown mixed findings in animals and humans. Objectives  The present experiments utilized a “reinforcer blocking” approach (i.e., rats were able to consume ethanol during treatment) to better understand the efficacy of these treatments for ethanol seeking and drinking using ethanol-dependent and nondependent rats. Materials and methods  In “nondependent” experiments, drugs (acamprosate 50, 100, and 200 mg/kg; naltrexone 0.1, 0.3, and 1.0 mg/kg) were administered over 3-week periods prior to operant sessions with a low response requirement to gain access to reinforcers for 20 min. For “dependent” experiments, rats were made dependent in vapor/inhalation chambers. Results  Acamprosate and naltrexone had similar effects on intake in nondependent and dependent rats; neither drug was selective for ethanol over sucrose drinking. In nondependent animals, naltrexone was more efficacious at more doses than acamprosate, and acamprosate’s effects were limited to a dose that also had adverse effects on body weight. Both pharmacotherapies showed more selectivity when examining reinforcer seeking. In nondependent rats, acamprosate and naltrexone had response-attenuating effects in ethanol, but not sucrose, groups. In dependent animals, acamprosate had selective effects limited to a decrease in sucrose seeking. Naltrexone, however, selectively decreased ethanol-seeking in nondependent rats. Conclusions  The naltrexone-induced decreases in seeking suggested a change in incentive motivation which was selective for ethanol in nondependent rats. The “nondependent” paradigm may model early stages of “problem drinking” in humans, and the findings suggest that naltrexone could be a good intervention for this level of alcohol abuse and relapse prevention.     

Interaction of estrone and estradiol with DNA and protein of liver and kidney in rat and hamster in vivo and in vitro

[6,7-³H] Estrone (E) and [6,7-³H]estradiol-17 (E₂) have been synthesized by reduction of 6-dehydroestrone and 6-dehydroestradiol with tritium gas. Tritiated E and E₂ were administered by oral gavage to female rats and to male and female hamsters on a dose level of about 300 g/kg (54 mCi/kg). After 8 h, the liver was excised from the rats; liver and kidneys were taken from the hamsters. DNA was purified either directly from an organ homogenate or via chromatin. The radioactivity in the DNA was expressed in the units of the Covalent Binding Index, CBI = (mol chemical bound per mol DNA-P)/(mmol chemical administered per kg b.w.). Rat liver DNA isolated via chromatin exhibited the very low values of 0.08 and 0.09 for E and E₂, respectively. The respective figures in hamster liver were 0.08 and 0.11 in females and 0.21 and 0.18 in the males. DNA isolated from the kidney revealed a detectable radioactivity only in the female, with values of 0.03 and 0.05 for E and E₂, respectively. The values for male hamster kidney were < 0.01 for both hormones. The minute radioactivity detectable in the DNA samples does not represent covalent binding to DNA, however, as indicated by two sets of control experiments. (A) Analysis by HPLC of the nucleosides prepared by enzyme digest of liver DNA isolated directly or via chromatin did not reveal any consistent peak which could have been attributed to a nucleoside-steroid adduct. (B) All DNA radioactivity could be due to protein contaminations, because the specific activity of chromatin protein was determined to be more than 3,000 times higher than of DNA. The high affinity of the hormone to protein was also demonstrated by in vitro incubations, where it could be shown that the specific activity of DNA and protein was essentially proportional to the concentration of radiolabelled hormone in the organ homogenate, regardless of whether the animal was treated or whether the hormone was added in vitro to the homogenate.Carcinogens acting by covalent DNA binding can be classified according to potency on the basis of the Covalent Binding Index. Values of 10³–10⁴ have been found for potent, 10² for moderate, and 1–10 for weak carcinogens. Since estrone is moderately carcinogenic for the kidney of the male hamster, a CBI of about 100 would be expected. The actually measured limit of detection of 0.01 places covalent DNA binding among the highly unlikely mechanisms of action. Similar considerations can be made for the liver where any true covalent DNA binding must be below a level of 0.01. It is concluded that an observable tumor induction by estrone or estradiol is unlikely to be due to DNA binding.Paper presented at the Satellite Symposium of the European Society of Toxicology, Rome, March 29, 1983     

Antiinfective and encrustation-inhibiting materials--myth and facts

Catheters, urethral and ureteral stents and other urological implants are frequently affected by encrustration and infection due to their permanent contact with urine. Indwelling urinary catheters provide a haven for microorganisms and thus require extensive monitoring. Several surface modification techniques have been proposed to improve the performance of devices including the immobilization of biomolecules, the incorporation of hydrophilic grafts to reduce protein adsorption, the creation of hydrophobic surfaces, the creation of microdomains to regulate cellular and protein adhesion, new polymers and antimicrobial coatings. Physico-chemical explanation to elucidate the mechanism of such encrustation or infection inhibiting materials is still not available. Our series of experiments showed a marked decrease of silver-activity in biological fluids which corresponds with the controversial clinical results obtained with silver coated urinary catheters. Rifampicin/minocycline coated catheters had very low activity against Gram-negative rods, enterococci and Candida spp., the main causing organisms of urinary catheter infection. Surface engineered materials and antimicrobial drug delivery systems will be the next generation of sophisticated urinary catheters and stents, if both efficacy as well as efficiency has been proved clinically.