异鸟苷掺入的富鸟嘌呤寡核苷酸的合成

目的改进异鸟苷单体的合成路线,合成异鸟苷掺入的富鸟嘌呤的寡核苷酸.方法以6-O-苄基鸟嘌呤为原料,经环氧开环、催化氢化、水解还原制备异鸟苷,经多步反应后得到异鸟苷亚磷酰化产物,采用固相合成方法合成异鸟苷掺入的富含鸟嘌呤的寡核苷酸.结果与结论经环氧开环能够区域选择性地得到N9取代的单一产物,收率提高到40%,并成功地合成了异鸟苷掺入的富含嘌呤十六聚寡核苷酸.本合成路线具有区域选择性强、路线简单、易操作、收率高等优点.     

苯丙素苷及其类似物的合成研究

利用葡萄糖6位羟基活性较高的特性, 2-(取代)苯乙基-β-D-吡喃葡萄糖苷在低温条件下直接与(取代)肉桂酰氯反应,区域选择性地生成6位酰化的葡萄糖苷,利用此方法很方便的得到了13个苯丙素苷类似物,利用1H NMR 和13C NMR方法确证了他们的结构.     

纤维喉镜与核磁共振（MRI）在喉癌诊断中的应用

将２５例喉癌的术前纤维喉镜检查和喉部ＭＲＩ与手术、病理进行比较，结果提示：纤维喉镜是喉癌诊断的最基本和最重要手段，能对Ｔ１、Ｔ２声门癌作出准确分期；ＭＲＩ对显示粘膜面肿瘤虽然并不重要，但能准确判断肿瘤对会厌前隙、声门旁隙、喉软骨及喉外的侵犯；两者作用互补，对喉癌的诊断、术前分期及手术方法的选择具有重要意义。     

The use of magnetic resonance imaging in the assessment of malignant vaginal fistulas

The objective of this study was to determine whether magnetic resonance imaging (MRI) could reliably demonstrate fistulas and any associated mass and to see whether these findings were beneficial in the management of the fistula. Twelve consecutive patients presenting with suspected vaginal fistulas were examined prospectively with MRI, using a combination of sequences, for the presence, extent and configuration of fistulas and any associated mass. Comparison was made with CT when available. All patients underwent examination under anesthesia (EUA) and the findings compared. Of the 12 women presenting, seven had vesico-vaginal fistulas (VVF) and seven had recto-vaginal fistulas (RVF). Four women had both types of fistulas. The underlying pathology was cervical cancer (seven cases), colonic cancer (three cases), breast cancer (one case) and ovarian cancer (one case). Vaginal fistulas were unequivocally seen on MRI in eight of 10 cases with fistulas. In the two cases with a difference between the MRI and EUA findings, the MRI was interpreted as showing more than was found at EUA. In the seven women with VVF, MRI detected five of the cases. In the seven women with RVF, MRI detected all seven cases. Magnetic resonance imaging was correct in determining the presence of recurrent disease in the pelvis when an associated mass was seen (seven cases). Computer-assisted tomography was compared in 10 cases and in six cases, the results were comparable and in four cases, more information was obtained from the MRI. Magnetic resonance imaging appears to be accurate in detecting and defining complex gynecologic fistulas and should be considered the investigation of choice to aid the planning of restorative, salvage or palliative surgery.     

阴道彩超检测卵巢动脉主干血流对卵巢肿瘤定性诊断的研究

目的：研究用阴道彩色超声多普勒血流显象（ＴＶＳ－ＣＤＦＩ）技术检测卵巢动脉主干血流定性诊断卵巢肿瘤。方法：应用ＴＶＳ—ＣＤＦＩ技术检测正常妇女５６例、卵巢良性肿物６２例及卵巢恶性肿瘤３２例卵巢动脉总干血流的Ａ（收缩期末血流速度峰值）、Ｂ（舒张期末血流速度峰值）、ＰＩ（搏动指数）、ＲＩ（阻力指数）值，并观察其图型特点。结果：卵巢恶性肿瘤的Ｂ、ＰＩ、ＲＩ与正常卵巢及良性肿瘤测值差异有显著性（Ｐ＜０．０５）；恶性卵巢肿瘤内血管为低阻力血管，卵巢动脉主干也随之发生变化，致ＰＩ、ＲＩ降低；将ＰＩ＝１．２０，ＲＩ＝０．６２作为诊断卵巢恶性肿瘤的界值，其灵敏度、特异度、阳性预测值、阴性预测值指标与声像图诊断相比，均明显提高。结论：ＴＶＳ－ＣＤＦＩ检测卵巢动脉总干血流对鉴别卵巢肿瘤的良、恶性具有重要的意义。     

心肌灌注显像剂^99mTc—tetrofosmin的临床前研究

对８名健康志愿者进行９９ｍＴｃｔｅｔｒｏｆｏｓｍｉｎ的临床前试验。采用一天或两天显像方案，行９９ｍＴｃｔｅｔｒｏｆｏｓｍｉｎ运动负荷和静息显像。通过采血和留尿测定药代动力学参数；采用全身扫描及感兴趣区等技术进行人体分布、靶／非靶比值、有效显像剂量和显像方案研究；依ＭＩＲＤ法估算各种用药情况下的内照射吸收剂量，进行辐射安全评价。结果：９９ｍＴｃｔｅｔｒｏｆｏｓｍｉｎ符合一次静脉给药的药代动力学二室模型，血药总清除率为１２７０ｍｌ／ｍｉｎ；心肌摄取较高，以百分注射剂量（％ＩＤ）为单位，给药后５分钟和６０分钟，运动负荷显像分别为３４０±０１３和２３６±０１９，静息显像则为３１１±１０２和２２２±０６８，前者摄取略高；在２７０～９２５ＭＢｑ给药剂量范围内，一天或两天方案的平面及ＳＰＥＣＴ显像图同样清晰，肝和肺本底低；内照射吸收剂量符合安全标准。临床前试验证明，９９ｍＴｃｔｅｔｒｏｆｏｓｍｉｎ安全有效，这为临床应用提供了依据。     

乳腺肿块^99mTc—MIBI显像规律与其组织病理学关系的初步探讨

为探讨９９ｍＴｃ甲氧基异丁基异腈（ＭＩＢＩ）乳腺显像诊断乳腺癌的临床价值及不同组织病理学特点的显像规律，对８４例乳腺肿块患者行９９ｍＴｃＭＩＢＩ显像检查。肘静脉“弹丸”式注射９９ｍＴｃＭＩＢＩ７４０～９２５ＭＢｑ，动态采集血流相、血池相、５分钟早期摄取相及６０、１２０分钟延迟相图像，并计算病变的早、晚期摄取比值。结果表明：乳腺病变显像特点随组织病理学类型不同而有明显差别。４３例乳腺癌中３７例诊断为阳性，６例假阴性；４１例良性病变中３例有放射性浓集。此法检出乳腺癌的灵敏度、特异性分别为８６０５％和９２６８％。因此，９９ｍＴｃＭＩＢＩ显像对鉴别乳腺良、恶性病变具有重要临床应用价值，但对癌细胞密度低的恶性肿瘤，如硬癌及有多发性坏死而血供不良的恶性肿瘤诊断效果不佳。     

核素显像和B超测算甲状腺重量的对比研究

对照研究核素显像和Ｂ超测算甲状腺重量的相关性，为临床提供较准确及简易的方法。３６３例甲亢病人１３１Ｉ治疗前分别进行γ显像和Ｂ超检查，以测算甲状腺体积（重量），其中６５例弥漫性甲状腺肿合并甲亢病人１３１Ｉ治疗后６个月重复两种检查。３６３例病人显像和Ｂ超测算甲状腺重量相关良好（ｒ＝０９３，Ｐ＜００１），总体上显像所得重量平均值大于Ｂ超值，腺体厚度是影响测算结果的主要因素；１３１Ｉ治疗后腺体厚度缩小最著，显像值大于Ｂ超值更明显。甲状腺重量测算在一定范围内两种方法可互相替代。１３１Ｉ治疗后，Ｂ超测定值为准。存在结节时，以显像为优。     

Three-dimensional visualization and measurement of conformal dose distributions using magnetic resonance imaging of bang polymer gel dosimeters

: The measurement of complex dose distributions (those created by irradiation through multiple beams, multiple sources, or multiple source dwell positions) requires a dosimeter that can integrate the dose during a complete treatment. Integrating dosimeter devices generally are capable of measuring only dose at a point (ion chamber, diode, TLD) or in a plane (film). With increasing use of conformal dose distributions requiring shaped, noncoplanar beams, there will be an increased requirement for a dosimeter that can record and display a 3D dose distribution. The use of a 3D dosimeter will be required to confirm the accuracy of treatment plans produced by the current generation of 3D treatment-planning computers.

: The use of a Fricke-infused gel and magnetic resonance imaging (MRI) to demonstrate the localization of stereotactic beams has been demonstrated (11). The recently developed BANG polymer gel dosimetry system (MGS Research, Inc., Guilford, CT), based on radiation-induced chain polymerization of acrylic monomers dispersed in a tissue-equivalent gel, surpasses ther Fricke-gel method by providing accurate, quantitative dose distribution data that do not deteriorate with time (6, 9). The improved BANG2 formulation contains 3% N,N′-methylene-bisacrylamide, 3% acrylic acid, 1% sodium hydroxide, 5% gelatin, and 88% water, where all percentage are by weight. The gel was poured into volumetric flasks, of dimensions comparable to a human head. The gels were irradiated with complex beam arrangements, similar to those used for conformal radiation therapy. Images of the gels were acquired using a Siemens 1.5T imager and a Hahn spin-echo pulse sequence (90°-τ-180°-τ-acquire, for different values of τ). The images were transferred via network to a Macintosh computer for which a data analysis and display program was written. The program calculates R2 maps on the basis of multiple TE images, using a monoexponential nonlinear least-squares fit based on the Levenberg-Marquardt algorithm. The program also creates a dose-to-R2 calibration function by fitting a polynomial to a set of dose and R2 data points, obtained from gels irradiated in test tubes to known doses. This function can then be applied to any other R2 map, so that a dose map can be computed and displayed.

: Through exposure to known doses of radiation, the gel has been shown to respond linearly with dose in the range of 0 to 10 Gy, and its response is independent of the beam energy or modality. Dose distributions have been imaged in orthogonal planes, and can be displayed in a convenient form for comparison with isodose plans. The response of the gel is stable; the gel can be irradiated at any time after its manufacture, and imaging can be conducted any time following a brief interval after irradiation.

: The polymer gel dosimeter has been shown to be a valuable device for displaying three-dimensional dose distributions. The imaged dose distribution can be compared easily with calculated dose distributions, to validate a treatment planning system. In the future, gels may be prepared in anthropomorphic phantoms, to confirm unique patient dose distributions.     

Transitional cell carcinoma of the ovary: Report of three cases

Background We investigated retrospectively the records and tissue samples of patients with primary ovarian transitional cell carcinoma to determine clinical and pathologic features. Methods The records of 3 patients with ovarian transitional cell carcinoma were reviewed using data from several imaging techniques: transvaginal ultrasound, computed tomography, and magnetic resonance imaging. We also determined levels of several tumor marker molecules; and the level of carbohydrate antigen 125 (CA 125), was examined by means of immunohistochemistry. Results The tumors of 2 patients were classified as pure trnasitional cell carcinoma; in the remaining patient, as predominantly transitional cell carcinoma. All tumors were bilateral, and 2 of the 3 tumors formed solid masses. Areas of irregular high intensity signals were seen in magnetic resonance images of the solid parts of the tumors. All 3 tumors tested positive for CA 125; histochemical expression was confined to the tumor cell membrane and/or the cytoplasm in all cases. The tumors of all 3 patients tested negative for carcinoembryonic antigen (CEA), and second-look laparotomies did not reveal any residual neoplasms in any of the patients. The patients have been in a disease-free state for 34, 42, and 14 months, respectively. Conclusion Our results suggest that transitional cell carcinomas tend to arise bilaterally and to form solid tumors. Magnetic resonance imaging was a useful diagnostic modality in these cases. Transitional cell carcinoma was characterized by the presence of CA 125 and the absence of CEA.