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1.
The trend in microelectronics toward printing features 0.25 μm and below has motivated the development of lithography at the 193-nm wavelength of argon fluoride excimer lasers. This technology is in its early stages, but a picture is emerging of its strengths and limitations. The change in wavelength from 248 to 193 nm will require parallel progress in projection systems, optical materials, and photo-resist chemistries and processes. This paper reviews the current status of these various topics as they have been engineered under a multiyear program at MIT Lincoln Laboratory  相似文献   
2.
Intracranial osteolipomas are rare lesions which occur in the region of the tuber cinereum. All cases reported to date have been incidental autopsy findings. We describe a patient who presented with a variety of neurological symptoms and had a typical osteolipoma surgically removed.  相似文献   
3.
Report on 2 fatal autoerotic cases. In the first case a 20-year-old man died due to the use of nitrous oxide (laughing gas) which he had used in a self-constructed breathing-machine. The nitrous oxide came from a cartridge which normally is used for aerosol cans for whipped cream. In the second case a 19-year-old man used a pressure-suit for military-jet pilots and inflated it with a 12-volt-compressor. Additionally the head was covered with 3 masks and a motorcycle helmet. Arms and legs were bound. The cause of death was a massive compression of the thorax.  相似文献   
4.
Myocardial infarction (MI) remains the leading cause of death in the western world. Despite advancements in interventional revascularization technologies, many patients are not candidates for them due to comorbidities or lack of local resources. Non-invasive approaches to accelerate revascularization within ischemic tissues through angiogenesis by providing Vascular Endothelial Growth Factor (VEGF) in protein or gene form has been effective in animal models but not in humans likely due to its short half-life and systemic toxicity. Here, we tested the hypothesis that PR1P, a small VEGF binding peptide that we developed, which stabilizes and upregulates endogenous VEGF, could be used to improve outcome from MI in rodents. To test this hypothesis, we induced MI in mice and rats via left coronary artery ligation and then treated animals with every other day intraperitoneal PR1P or scrambled peptide for 14 days. Hemodynamic monitoring and echocardiography in mice and echocardiography in rats at 14 days showed PR1P significantly improved multiple functional markers of heart function, including stroke volume and cardiac output. Furthermore, molecular biology and histological analyses of tissue samples showed that systemic PR1P targeted, stabilized and upregulated endogenous VEGF within ischemic myocardium. We conclude that PR1P is a potential non-invasive candidate therapeutic for MI.  相似文献   
5.
Three-dimensional Fourier transform (3-DFT) magnetic resonance imaging (MRI) offers advantages in terms of signal-to-noise (S/N) per unit of time for the case where a large number of slices is desired. This advantage is enhanced when the relaxation time, T(1 ), is short. Because time limitations in 3-DFT imaging force the use of short time intervals, TR, between excitations of a slice, lesion contrast is often undesirable at mid-and high-field strength even when the S/N is good. At low fields, where T(1) values are short, high S/N and contrast can both be achieved with 3-DFT MR images. The conceptual and analytical aspects of low-field 3-DFT MRI are presented and demonstrated at 640 G.  相似文献   
6.
Autosomal recessive polycystic kidney disease (ARPKD) is characterized by the formation of large collecting tubule and ductular cysts that often result in renal insufficiency within the first decade of life. Understanding the process leading to cyst formation will require the identification and characterization of genes involved in the etiology of this disease. In this regard, we previously described the generation of a mouse model (TgN737Rpw) for ARPKD and the cloning of a candidate gene. Here we show direct involvement of the Tg737 gene in collecting duct cyst formation by expressing the wild-type Tg737 cDNA as a transgene in TgN737Rpw mutants. In contrast to TgN737Rpw mutants, the "rescued" animals survive longer, have normal renal function and normal localization of the EGFr to the basolateral surfaces of collecting duct epithelium.  相似文献   
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In this study, fresh and processing quality traits were collected on a total of 312 Country Hams. Phenotypic correlations between traits were estimated and numerous values were significantly different (P<0.05) from zero. Yield was significantly correlated with several fresh pork quality traits measured on the fresh hams, including subjective color (0.34) and lipid percentage (0.32). Some meat color traits were significantly correlated, including associations between the color scores taken on the fresh and cured hams. Correlations between fresh pork quality traits were also determined, with results showing significant correlations between ultimate pH and other pork quality traits. The results indicate that yield can be maximized if hams with good fresh pork quality parameters are used for curing. The correlations estimates are helpful for understanding of the biological mechanisms behind the production of dry-cured hams and can potentially be used to improve the efficiency of the dry-cured ham production chain.  相似文献   
10.
Gitis V  Adin A  Nasser A  Gun J  Lev O 《Water research》2002,36(17):4227-4234
A new method for the study of pathogen transport in porous media is presented. The method is based on conjugation of fluorescent dyes to target bacteriophages and application of the modified bacteriophages for tracer studies. We demonstrate that the relevant transport determining properties of Rhodamine and several fluorescein-labeled phages are practically identical to those of the native bacteriophages. The advantages of the proposed method relative to direct enumeration of bacteriophages by plaque forming unit method, turbidity, fluorescent microspheres, and other alternative tracers are discussed. Notable advantages include simple quantitation by optical methods, unbiased signals even when virus aggregates are formed, and the ability to decouple inactivation kinetics from transport phenomena. Additionally, the signal reflects the removal and transport of the studied microorganism and not a surrogate.  相似文献   
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