活血化瘀对冠心病胰岛素抵抗的研究

目的 :探讨活血化瘀法对冠心病胰岛素抵抗的临床疗效。方法 :观察 46例冠心病患者接受活血化瘀治疗前后空腹血糖、胰岛素、胰岛素敏感性指数的变化 ,评定其临床疗效。结果 :治疗前后比较 ,空腹血糖无差异 (P >0 .0 5 ) ,胰岛素水平治疗后明显下降 (P <0 .0 5 ) ,胰岛素敏感性指数显著增高 (P <0 .0 5 )。结论 :活血化瘀法具有改善冠心病患者胰岛素抗抵作用。     

枸杞的光谱学鉴别

目的 探讨枸杞与熏硫枸杞的鉴别方法.方法 将枸杞与熏硫枸杞进行光谱学检测.结果 正品枸杞紫外光谱各个等级吸光度均大于熏硫枸杞;熏硫枸杞的红外光谱在3 337 cm-1、1 041 cm-1处有较强的峰,正品枸杞无此强峰.结论 所选用方法对枸杞的鉴别有参考价值,在中药质量控制方面的应用为枸杞鉴定开辟了新思路.     

Inversion recovery image reconstruction with multiseed region-growing spin reversal

A new algorithm is introduced for inversion recovery (IR) image reconstruction. The original complex image is modeled as a product of three factors: magnitude, polarity, and a smoothly changing phase factor. The simple binary polarity factor is first unified by a region-growing spin reversal (RGSR) operation, allowing the phase factor to be extracted. Multiplying the complex conjugate of the phase factor with the original complex data yields the desired IR contrast. The RGSR process is repeated with multiple seeds distributed in the field of view (FOV), and the results are added together, enabling disconnected tissues in the FOV to be handled. The extracted phase factor is filtered to reduce noise and artifacts, without losing useful information. The method is fully automatic and has been used practically in a large number of clinical examinations. The algorithm may also be useful for phase correction in simple proton spectroscopic imaging.     

Blood Plasma/Implant Interfaces FT—IR Studies of Adsorption on Polyethylene and Heparin-Treated Polyethylene Surfaces

Described is an attenuated total reflection (ATR), Fourier Transform infrared (FT–IR) technique useful for studying the adsorption of blood plasma proteins onto polymer surfaces. This technique has the advantage of employing Whole blood plasma and has detected differences between the species adsorbed onto heparin-treated polymers as compared to the species adsorbed on untreated polymers. Differences detected consist of 1) changes in conformation and/or composition of proteins adsorbed on treated and untreated polymers, and 2) changes in amounts of carbohydrate-containing materials on the treated and untreated polymer surfaces.
The advantages of FT–IR are its extreme sensitivity and its ability to work with highly complex systems such as whole blood plasma. These abilities should be of great value for providing direct molecular level information concerning protein adsorption from intact blood systems.     

Insulin resistance causes impaired vasodilation and hypofibrinolysis in young women with polycystic ovary syndrome

INTRODUCTION: Insulin resistance, a novel cardiovascular risk factor, is often associated with increased plasminogen activator inhibitor-1 levels and impaired vasodilation. Insulin infusion in the forearm induces plasminogen activator inhibitor-1 and tissue plasminogen activator expression and endothelium-dependent vasodilation in normal subjects. The present study explores the relationship between insulin-induced vasodilatory and fibrinolytic properties of the endothelium in women with polycystic ovary syndrome, frequently affected by insulin resistance and early atherosclerosis. MATERIALS AND METHODS: Metabolic, hormonal and fibrinolytic parameters were evaluated in 64 patients with polycystic ovary syndrome (19 insulin-resistant and 45 insulin-sensitive) and in 25 controls. In 16 women with polycystic ovary syndrome, 8 insulin-resistant and 8 insulin-sensitive, blood flow, plasminogen activator inhibitor-1 and tissue plasminogen activator expression were evaluated during insulin infusion into the forearm. RESULTS: Elevated basal plasminogen activator inhibitor-1 levels were found in women with polycystic ovary syndrome, correlating directly with insulin levels. Plasminogen activator inhibitor-1 expression increased during insulin infusion in all women with polycystic ovary syndrome, but was delayed and sustained in insulin-resistant patients (p<0.01). Vasodilatory response to insulin was blunted (p<0.01) and tissue plasminogen activator expression abolished in insulin-resistant patients (p<0.01). CONCLUSION: Our study demonstrates that women with polycystic ovary syndrome and insulin resistance show a blunted endothelial-dependent vasodilation. The impaired endothelial release of tissue-plasminogen activator and the sustained plasminogen activator inhibitor-1 release during insulin infusion suggest a hypofibrinolytic state in PCOS patients with insulin resistance. This hemodynamic and fibrinolytic derangement may contribute to the pathogenesis of early atherosclerosis in insulin resistance.     

Structural Effect on Thermal Cure and Property of Naphthalene‐Based Epoxies: Preparation and Characterization

Summary: Three naphthalene‐based epoxy monomers containing different size of linkages between two naphthalene rings: C? C covalent bond ( 1 ), methylene ( 2 ), cycloaliphatic hydrocarbon derived from limonene ( 3 ) were prepared, and the effect of molecular structure on thermal cure behavior and property analyzed. Judged from the combination of the dynamic DSC and isothermal FTIR results, the cure reactivities were found to increase in the order of 1 > 2 > 3 when dicyandiamide was used in the curing systems, and the situation was slightly different in the monomer/4,4′‐methylenedianiline systems. The differences in reactivity as well as in thermal and mechanical properties for the epoxies can be attributed to the differences of configuration and conformational changes during the formation of crosslinked networks. These thermosets exhibited high glass transition temperature (T_g) and had excellent thermal oxidative resistance.

DSC thermograms for epoxy/dicyandiamide systems at a heating rate of 10 °C · min^?1.     

Field evaluation of the efficacy and persistence of insect repellents DEET, IR3535, and KBR 3023 against Anopheles gambiae complex and other Afrotropical vector mosquitoes

Synthetic insect repellents, IR3535 and KBR 3023 (also known as picaridin, or by the trade name Bayrepel, were tested in Burkina Faso against mosquito vectors of disease to compare their relative efficacy and persistence profiles to those of the 'gold standard' DEET. Collection of >49000 mosquitoes (approximately 95% belonging to the Anopheles gambiae complex) showed that after an exposure of 10h, KBR 3023 produced the highest protection against anophelines, followed by DEET, then IR3535. The response of aedines was more variable. By fitting a logistic plane model we estimated 95% effective dosages (ED95) for An. gambiae s.l., as well as a decay constant characterizing the exponential loss of repellent from the skin, with time. The ED95 values for DEET, IR3535, and KBR 3023 were 94.3, 212.4, and 81.8 microg/cm2 respectively. The decay constants were estimated at -0.241, -0.240, and -0.170 h(-1) respectively. The corresponding estimates of half-life were 2.9, 2.9, and 4.1h. Immunoenzymatic detection of the circumsporozoite protein (CSP) of Plasmodium falciparum in 842 An. gambiae s.l. showed that CSP-positive mosquitoes were equally frequent in treated and control subjects, indicating that the repellents could produce a reduction in the number of malaria infectious bites.     

Mechanisms of Moisture Sorption in Barrier Polymers Used in Food Packaging: Amorphous Polyamide vs. High‐Barrier Ethylene‐Vinyl Alcohol Copolymer Studied by Vibrational Spectroscopy

The nature of the association between sorbed water and two high‐barrier hydrophilic polymers used in oxygen‐sensitive food packaging, and exhibiting opposite oxygen barrier behavior in the presence of moisture, has been studied by FT‐Raman and FT‐Infrared spectroscopy. The polymers considered in this work were an ethylene‐vinyl alcohol copolymer with superior oxygen barrier properties (32 mol‐% of ethylene EVOH) and an amorphous polyamide (aPA). The results revealed that for the latter glassy amorphous polymer, water molecules associate with the C?O and N? H groups of the ca. 10% “free” amide moieties, being the excess sorbed water self‐associated in clusters; thus, moisture sorption does not appear to disrupt the originally present hydrogen‐bonded amide groups. This “unusual” behavior leads to an overall increase in the extension of the hydrogen‐bonding, which may help explain the lower oxygen permeability displayed by the aPA with increasing relative humidity on the basis of the known free‐volume competing mechanism. Differently, water sorption appears to progressively disrupt the strong polymer self‐association present in the very efficient high‐barrier semicrystalline EVOH material by hydrogen‐bonding to hydroxyl groups, hence leading to the well‐known highly plasticized rubbery structure with much lower intermolecular cohesion and oxygen barrier.

FT‐IR spectra of severely dried, dry (dotted), and water‐equilibrated (thicker line) aPA in the range 2 600–3 800 cm^?1.     

药用矿物蒙脱石的红外光谱分析

目的：弄清蒙脱石层状晶体结构中水的变化规律,为其药用机制研究和药物的开发利用提供依据。方法：从粘土矿物中分离纯化蒙脱石,运用红外光谱分析技术,对蒙脱石的化学结构进行分析。结果：得到了有关蒙脱石分子水的信息和化学结构变化的基本规律。结论：蒙脱石是一种膨胀吸附性粘土矿物,可作为药物活性成分或赋形剂。