高分辨率CT对颞部疾病的检查价值

目的：探讨高分辨率CT（HRCT）对颞部疾病的检查价值。方法：对43例颞部疾病患者行常规CT和高分辨率CT（HRCT）检查所获图像对比分析，并讨论HRCT的检查技术和图像后处理。结果：HRCT对病变的显示率及病变引起骨质破坏的程度，病变边缘，轮廓的显示均明显优于常规CT，尤其能清楚显示常规CT难以显示的中耳及内耳的细微结构，结论：高分辨率CT是颞部疾病的首选检查方法，使用高分辨率CT对颞部疾病的检查给临床提供更多，更准确的诊断信息。     

Intratemporal vascular tumors: detection with CT and MR imaging

The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion.     

DNA-directed alkylating agents. 3. Structure-activity relationships for acridine-linked aniline mustards: consequences of varying the length of the linker chain

Four series of acridine-linked aniline mustards have been prepared and evaluated for in vitro cytotoxicity, in vivo antitumor activity, and DNA cross-linking ability. The anilines were attached to the DNA-intercalating acridine chromophores by link groups (-O-, -CH2-, -S-, and -SO2-) of widely varying electronic properties, providing four series of widely differing mustard reactivity where the alkyl chain linking the acridine and mustard moieties was varied from two to five carbons. Relationships were sought between chain length and biological properties. Within each series, increasing the chain length did not alter the reactivity of the alkylating moiety but did appear to position it differently on the DNA, since cross-linking ability (measured by agarose gel assay) altered with chain length, being maximal with the C4 analogue. The in vivo antitumor activities of the compounds depended to some extent on the reactivity of the mustard, with the least reactive SO2 compounds being inactive. However, DNA-targeting did appear to allow the use of less reactive mustards, since the S-linked acridine mustards showed significant activity whereas the parent S-mustard did not. Within each active series, the most active compound was the C4 homologue, suggesting some relationship between activity and extent of DNA alkylation.     

骨巨细胞瘤的MRI诊断价值

目的探讨骨巨细胞瘤的MRI表现特点及其病理基础。资料与方法搜集经手术病理证实的12例骨巨细胞瘤患者资料，分析其MRI征象并与病理结果对照。结果T1WI上肿瘤实体表现为低、等信号，T2WI上为不均匀高信号，Gd-DTPA增强扫描呈中度到明显强化。此外，MRI还可显示肿瘤内坏死、出血、含铁血黄素沉着等。结论MRI能够提供比较全面的影像学信息，可提高对骨巨细胞瘤诊断的准确性。     

The fate of N1'-methanesulphonyl-N4'-(9-acridinyl)-3'-methoxy-2',5'-cyclohexadiene- 1',4'-diimine (m-AQDI), the primary oxidative metabolite of amsacrine, in transformed Chinese hamster fibroblasts

The cytotoxicity of the anti-leukaemia drug amsacrine (m-AMSA) has been suggested to result from its oxidative metabolism to the corresponding quinonediimine, N1'-methanesulphonyl-N4'-(9-acridinyl)-3'-methoxy-2',5'-cyclohexad iene-1',4'- diimine (mAQDI). The metabolic fate of mAQDI was examined in cultured CHO cells (subline AA8) to identify the end products to be expected following oxidative metabolism of m-AMSA. [Acridinyl-G-3H]-m-AQDI was rapidly accumulated by AA8 cells in phosphate buffered saline with complete conversion in less than one minute to m-AMSA, macromolecular adducts and polar low molecular weight species, each of these three classes being formed in approximately equal amounts. Two of the polar products were chromatographically identical to those formed on reaction of m-AQDI with reduced glutathione. These were identified by 1H NMR spectroscopy as the 1,4-addition product 5'-(S-glutathionyl)-m-AMSA and the previously unreported isomeric 6'-(S-glutathionyl)-m-AMSA. These thiol adducts were also formed rapidly from m-AQDI in deproteinized cell lysates indicating a non-enzymatic process, although the possibility of enzymatic catalysis in intact cells has not been eliminated. The absence of such products in AA8 cells after treatment with m-AMSA places an upper limit of 1% per hour on the rate of its oxidative metabolism in these cells and suggests that generation of m-AQDI is unlikely to be responsible for the cytotoxicity of m-AMSA in cultured tumour cells.     

Conducting applied research on Vietnam combat-related post-traumatic stress disorder

A paradigmatic shift in post-traumatic stress disorder (PTSD) research is underway. Formistic and mechanistic research designs, characterized by single-category, single-cause, single-effect models, gradually are being replaced by contextual and organistic research designs that feature multi-category, multi-cause, and multi-effect interactional models. Such changes in diagnostic and treatment outcome research require solving many methodological issues in such areas as: measuring types of traumas and stressors; measuring PTSD symptoms and subtypes; measuring subject dispositional characteristics (such as ethnic differences); assessing concurrent and/or pre-existing psychiatric (Axis I) disorders; classifying personality styles and concurrent and/or pre-existing personality (Axis II) disorders; evaluating phase in the development of PTSD as a disorder; measuring current environmental stresses and interpersonal interactions; and assessing secondary gains and readiness for treatment. These and other methodological problems must be addressed as research on PTSD shifts to longitudinal measurement of subjects randomly assigned to treatment conditions.     

NLA-1: a 2-nitroimidazole radiosensitizer targeted to DNA by intercalation.

Targeting of electron affinic radiosensitizers to DNA via reversible non-covalent intercalative binding has potential for increasing sensitizer concentrations locally at the DNA target while decreasing accessibility to reductases responsible for bioactivation and cytotoxicity. We have prepared an DNA-targeted acridine-linked 2-nitroimidazole (NLA-1) as an example of such a compound. NLA-1 binds reversibly to DNA with an affinity similar to 9-aminoacridine, and is approximately 1000 times more potent than MISO as a cytotoxin, despite a similar reduction potential. It shows less enhancement of cytotoxicity under hypoxia (5- to 6-fold) than does MISO (approximately 11-fold), but is a potent hypoxia-selective radiosensitizer in AA8 cells with a concentration for an enhancement ratio of 1.6 (C1.6) of 9 microM. The mean intracellular concentration at the C1.6 is 400 microM, on which basis its potency is about twice that of MISO. The in vitro therapeutic index (aerobic cytotoxic potency/hypoxic C1.6) of NLA-1 is approximately 6-fold lower than that for MISO. NLA-1 lacks radiosensitizing activity against SCCVII or EMT6 tumors in vivo at the maximum tolerated dose (MTD) of 100 mumol.kg-1.     

Percutaneous isolated liver perfusion for treatment of hepatic malignancy: preliminary report.

Chemotherapy for primary or metastatic hepatic malignancy is limited by poor tumor response and dose-related systemic toxicity. As an alternative to chemotherapy infusion by vein or by the hepatic artery, the authors have developed a percutaneous technique of isolated liver perfusion that allows the regional delivery of high-dose chemotherapy to the liver with little systemic toxicity. After placement of a hepatic artery infusion catheter, an 18-F double-balloon catheter is placed into the inferior vena cava through the opposite femoral vein. Balloons are inflated above and below the hepatic veins, thus isolating hepatic venous outflow. The effluent passes through fenestrations in the catheter and is pumped through charcoal hemoperfusion filters where the drug is removed. The filtered blood is returned to the patient through the internal jugular vein. Fifteen treatments have been conducted in eight patients in a phase I dose-escalation study with use of 5-fluorouracil (5-FU). While it is premature to assess tumor response to isolated liver perfusion, the data demonstrate that the procedure is safe and is tolerated by patients. Pharmacokinetic studies show a 5-FU extraction of up to 85%, with minimal drug leakage into the systemic circulation. This technique shows potential for improving liver tumor response while decreasing systemic toxicity.