Clinical Analysis of 57 Patients with Ovarian Dysgerminoma

Objective  Ovarian dysgerminoma is an uncommon ovarian malignancy, Its clinicai features are special and there are many factors affecting its prognosis. If treated properly, the patient can be cured. Otherwise it may endanger the patient’s life. The aim of this study is to investigate the clinical features and factors related to prognosis of ovarian dysgerminoma. Methods  Data from 57 patients with pure ovarian dysgerminoma were analyzed retrospectively. The patients were admitted to the Cancer Center, Sun Yat-sen University from January 1.1964 to December 31, 2000. Results  The main clinical features were abdominal mass (56.1% ), abdominal pain (21.1% ), abdominal swelling (17.5%.), vaginal bleeding (5.3% )and genital tract abnormalities (5.3%). Twenty-six patients had stage I diseases, 8 stage II.9 stage III.1 stage IV and 13 recurrent and persistent diseases. The uterus was involved in 41.2% of patients with stage II -III diseases. Combined modality was given to 52 cases and a single-method treatment to 5 cases. The total overall 5 and 10-year survival rates for stages I-IV was 80.1 % and 70.0% respectively. The 5-year survival rate for stage I was 100%, stage II 55.2%. stage III 55.6% and stage IV 0%; for recurrent and persistent diseases, 72.7%. The stage I group of 12 patients. received adnexectomy and 14 patients underwent hysterectomy and adnexa removal. There was no significant difference between the 5 and 10-year survival rates (all 100%). Of the 23 patients in the stage I group to whom oniy chemotherapy was given after operation, 19 cases received 3 or more courses and were well without recurrence; 4 patients received only one course and one of them recurred 21 months after the operation. In the group of stages II and III cases, the 5-year survival rate was 86.7% for those whose chemotherapy courses were 3≥ 4 and 25.0% for patients who received less than 4 courses of chemotherapy (P<0.05). Conclusions  The prognosis of ovarian dysgerminoma is closely related to the disease stage and treatment modality. A fertility-preserving operation can be considered in early -staged patients, but caution needs to be exercised in the middle to late staged cases. Good results can be achieved with an operation-based combined modality in recurrent patients.     

灯盏花素对豚鼠单一心室肌细胞ICa的抑制作用

目的：观察灯盏花素对豚鼠单一心室肌细胞钙离子电流（ＩＣａ）的影响。方法：应用全细胞膜片钳制技术。结果：灯盏花素能明显抑制心室肌细胞的Ｃａ＾２＋通道,使ＩＣａ减小。此作用有明显的电压依赖性。在峰电流电压下作用最明显,而对其反转电位无明显影响。在指令电位０ｍＶ时,０．５ｍｇ％灯盏花素使ＩＣａ减小５．４％,１ｍｇ％灯盏花素使ＩＣａ减小２２．９％（Ｐ〈０．０１）,２ｍｇ％灯盏花素使ＩＣａ减小４５．０％（Ｐ     

腺苷三磷酸结合盒转运蛋白A1在动脉粥样硬化中的作用及其受控特点

目的:分析腺苷三磷酸结合盒转运蛋白A1(ATP binding cassette transport proteion A1,ABCA1)在动脉粥样硬化中的作用及其受控机制。资料来源:以“腺苷三磷酸结合盒转运蛋白A1”为检索词,应用计算机在Pubmed、中文全文数据库CNKI中检索2000-01/2006-11腺苷三磷酸结合盒转运蛋白A1与人有关的期刊文献,前者限定语言种类为英文,后者限定语言种类为中文。资料选择:对英文文献390篇、中文文献58篇初审。纳入标准:①与ABCA1结构及功能有关的文献。②与核受体有关的文献。③与载脂蛋白AⅠ有关的文献。④与ABCA1基因的突变、单核苷酸多态性有关的文献。⑤ABCA1蛋白、核受体、ABCA1基因的突变、单核苷酸多态性与动脉粥样硬化有关的文献。排出标准:①与哮喘、癌症、代谢性疾病有关的文献。②相关文献中内容相似的文献。③综述文献。资料提炼:选取3篇涉及ABCA1结构、功能的基础内容;18篇涉及与核受体的内容;2篇涉及载脂蛋白AⅠ的内容;7篇涉及ABCA1基因的突变、单核苷酸多态性的内容;9篇涉及ABCA1蛋白、核受体、ABCA1基因的突变、单核苷酸与动脉粥样硬化的内容。其中30篇列为参考文献。资料综合:分析了腺苷三磷酸结合盒转运体A1的结构和功能的基本情况;文献显示腺苷三磷酸结合盒转运体A1在动脉粥样硬化发病过程中起重要作用;核受体对腺苷三磷酸结合盒转运体A1的表达有调节,且腺苷三磷酸结合盒转运体A1受基因调控。结论:腺苷三磷酸结合盒转运体A1可能是与动脉粥样硬化密切相关的重要候选基因;深入探讨其机制,有利于开发新药防治动脉粥样硬化。     

Kinetic investigation of the hydrolysis of uranium hexafluoride gas

UF₆ is commonly employed in enrichment technologies and is known to react rapidly with water vapor to form radioactive particulates and hydrofluoric acid vapor. The kinetics of the UF₆ hydrolysis reaction have been observed directly for the first time. The rate appears to be half order and second order for UF₆ and water, respectively, with a rate constant of 1.19 ± 0.22 Torr^−3/2 s⁻¹. The proposed mechanism involves formation of the [UF₆·2H₂O] adduct via two separate reactions.

Direct observation of the hydrolysis reaction kinetics of gaseous UF₆ have been measured under low-pressure conditions.

Uranium hexafluoride (UF₆) is a key compound in the nuclear fuel cycle as the material employed in commercial enrichment, enabling production of the fuel for electricity production in nuclear power reactors. Studies evaluating the safety implications of small or large releases of UF₆ within a processing facility have been performed previously,^1–3 as it is well known that this material undergoes a hydrolysis reaction in ambient air according to the simplified reaction:UF₆(g) + 2H₂O(g) → UO₂F₂(s) + 4HF(g)producing both uranium particulates and hydrofluoric acid vapor. Recent work⁴ has explored the formation of the uranium particulate materials but the precise molecular mechanism of the initiating reaction has yet to be verified. Previous efforts to characterize this reaction have focused on spectroscopic measurements^5–7 and computational studies.^8–13 The experimental studies have focused on the spectroscopic detection of uranium species but lacked the temporal resolution to observe the reaction or identify any transient species. Unfortunately, there are major discrepancies between the experimentally observed reaction and computationally predicted mechanisms. For example, the computational studies suggest large thermodynamic energy barriers that would likely prevent the reaction of UF₆ and water vapor,^9–13 yet the hydrolysis reaction is known to occur quickly and completely under ambient conditions.^5–7 Additionally, one of the long-suspected intermediates of this reaction, UOF₄, has not been successfully identified under extreme conditions designed to optimize its production such as reacting water with a 5000-fold excess of UF₆.¹⁴ Relevant spectroscopy measurements need to be performed to inform computational modelling because the mechanism may not be driven by a stepwise reaction of UF₆ and water molecules.One prior study performed an indirect measurement of the rate of the UF₆ hydrolysis by monitoring the ingrowth of hydrogen fluoride with a laser-based analyzer.¹⁵ The reported rate constant of 4 ± 4 × 10⁻¹⁸ cm³ s⁻¹ remains questionable as limited experimental details were reported. Based on their findings, and assuming pseudo-first order kinetics under these reaction conditions in excess water vapor, the reaction half-life is calculated to be on the order of 1 ms or less. Standard infrared spectroscopy instrumentation cannot scan with submillisecond temporal resolution, requiring specialized instrumentation that has only recently become available.This work focused on observing the disappearance of UF₆ under low pressure conditions by probing the most sensitive infrared (ν₃ antisymmetric stretching) vibrational band,¹⁶ located at 625 cm⁻¹, using a 5 m long-path length cell. The long path length combined with the sensitivity of the band allow the reaction rate to be investigated at sub-Torr partial pressures. The reaction is slow enough at these pressures to allow direct kinetic measurements of the hydrolysis to be made using a typical infrared spectrometer.Experiments were performed in a 5 m long-path length gas cell fitted to an ABB MB3000 Fourier transform infrared spectrometer. The chamber was exposed to fluorine gas to passivate materials of construction and remove water from surfaces within the spectroscopy cell before each experiment. The UF₆ was then introduced into the evacuated cell at pressures between 10 and 30 mTorr and ambient temperature (22.5 ± 0.5 °C). (Warning: UF₆ is a radioactive gas that forms highly toxic hydrogen fluoride in the presence of water.) After initial infrared spectroscopy measurements were made, 60 or 80 mTorr of water vapor was injected into the system and allowed to react. Typical infrared spectra collected during the hydrolysis reaction occurred during 0.5–2 min for these conditions, as shown in Fig. 1A. Note, the reactions that occurred when water vapor was introduced at these partial pressures were approximately an order of magnitude faster than any reactions of UF₆ with materials of construction. The observed rates (Fig. 1B) were significantly slower than those expected from diffusion-limited reactivity, suggesting that mixing occurred rapidly from the injection method.Open in a separate windowFig. 1(A) Select infrared spectra showing the 625 cm⁻¹ band of UF₆ just before introducing water vapor (red) and every 10 s after (blue) for 1 min. (B) Example of absorbance change of the 625 cm⁻¹ band over time during a typical hydrolysis experiment. The rate of disappearance of the UF₆ increased about a factor of 10 when H₂O was introduced.Typical changes in the absorbance due to the reaction are shown in Fig. 2 after correction for reaction with materials of construction. Each figure is the average of three experiments and the data are corrected using a linear regression of the absorbance before time zero extrapolated through the points used for initial rate determination. The initial slope of the decay was fit using a linear regression on the first five data points for each reaction condition. The data were converted from absorbance units to mTorr, and the resulting conditional reaction rates in mTorr s⁻¹ are shown in Open in a separate windowFig. 2The normalized absorbance of the 625 cm⁻¹ band in a 5 m path length cell for various partial pressures of UF₆ and water vapor. Water vapor was injected at time = 0 s.Conditional reaction rates of the hydrolysis of gaseous UF₆ in the presence of H₂O vapor

Acute coronary syndromes

The first 150 words of the full text of this article appear below. Key points Coronary artery disease accounts for >30% ofdeaths in Western society. The diagnosis of myocardial infarctionshould be qualified by size, causation and time from occurrence. Mortalityis reduced by immediate or ‘primary’ percutaneouscoronary intervention or thrombolysis within the first 24 hof onset of ST-segment elevation myocardial infarction. Strategiesto reduce platelet activation (glycoprotein IIb/IIIa receptorantagonists, or clopidogrel) are now recommended in the treatmentof high-risk non-ST-segment myocardial infarction/unstable angina. Elevatedserum troponins may be the result of non-ischaemic myocardialdamage, especially in critical illness.