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941.
Phenacetin-induced sulfhemoglobinemia was diagnosed in a middle-aged woman with a 6-month history of cyanosis and a 10-year history of ingestion of analgesics. The laboratory and clincial diagnosis of sulfhemoglobinemia and methemoglobinemia are discussed. The reviewed medical literature suggests that the cyanosis of chronic phenacetin or acetanilid use is generally due to sulfhemoglobinemia rather than methemoglobinemia. 相似文献
942.
943.
In long-term field trials lasting approximately 12 months attempts were made to determine whether the cell-free HVT vaccine was as effective in reducing MD losses as the cell-associated HVT vaccine. Four trials were conducted in which flocks were vaccinated with either the cell-free or the cell-associated HVT vaccine. The cell-free HVT vaccine was as safe and effective in preventing MD as the cell-associated HVT vaccine. Although there were some losses due to MD in all flocks, there were also losses due to lymphoid leukosis, multiple hemangioma, liposarcoma or coccidiosis. Egg production was essentially the same in flocks vaccinated with the cell-free HVT vaccine as in those vaccinated with the cell-associated HVT vaccine. 相似文献
944.
A technique has been developed that enables most humans to establish rapid self-regulatory control of their own skin temperature when provided with immediate visual feedback information concerning variations in local skin temperature. Training took place during 15-min periods within 45-min sessions. Clear evidence of learning was usually manifested within 4 sessions. After acquisition occurred, mean change per session was approximately 2.2 degrees F, ranging up to 6.5 degrees F. Training was continued with some subjects who were taught to alter temperature in opposite directions during successive periods on the same day. After practice, these subjects routinely displayed ranges of 9-14 degrees F within 15 min. 相似文献
945.
The relationship of hay fever symptoms and changes in the number of circulating basophils was studied in 12 subjects clinically sensitive only to ragweed and in 10 nonatopic subjects before, during, and after the ragweed season. Total white blood counts, absolute basophil counts, and symptom scores were recorded twice weekly from mid-June through October, 1974, and compared with the ragweed pollen count. The results indicated that the absolute and relative number of basophils were significantly elevated (p less than 0.001) in the hay fever group when symptoms occurred. As the symptom score of the allergic group increased during the ragweed season, the number of basophils also increased, only to decrease to control values when symptoms subsided. The basophil counts of the atopic group were significantly higher than those of the nonatopic group during the control periods. The nonatopic group also showed a significant elevation of basophils during the ragweed season, but to a much lesser extent than the atopic group. It is concluded that: (1) subjects with symptomatic hay fever have a significantly elevated absolute and relative basophil count which correlates with the exacerbation and remission of symptoms; (2) nonatopic subjects also have a small but significant elevation of basophils during the ragweed season; and (3) the elevation of basophils in the atopic group during symptoms is significantly greater than in the nonatopic group during the ragweed season. 相似文献
946.
947.
Electroluminescence: From White to Red: Electric‐Field Dependent Chromaticity of Light‐Emitting Electrochemical Cells based on Archetypal Porphyrins (Adv. Funct. Mater. 37/2016)
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948.
The emergence of IR hyperspectral sensors in recent years enables their use in remote environmental monitoring of gaseous plumes. IR hyperspectral imaging combines the unique advantages of traditional remote sensing methods such as multispectral imagery and nonimaging Fourier transform infrared spectroscopy, while eliminating their drawbacks. The most significant improvement introduced by hyperspectral technology is the capability of standoff detection and discrimination of effluent gaseous plumes without need for a clear reference background or any other temporal information. We introduce a novel approach for detection and discrimination of gaseous plumes in IR hyperspectral imagery using a divisive hierarchical clustering algorithm. The utility of the suggested detection algorithm is demonstrated on IR hyperspectral images of the release of two atmospheric tracers. The application of the proposed detection method on the experimental data has yielded a correct identification of all the releases without any false alarms. These encouraging results show that the presented approach can be used as a basis for a complete identification algorithm for gaseous pollutants in IR hyperspectral imagery without the need for a clear background. 相似文献
949.
950.
Filter deposits from silver bromide sols give usable photographic layers provided a small quantity of gelatin, corresponding to only a fraction of maximum adsorption, is added prior to filtration. The response to light, latensification and sensitization of such layers corresponds very closely to that of conventional gelatin-based fine-grain emulsions. It is shown that emulsion layers can be converted to filter deposits without sacrifice of response and with pronounced benefit in certain applications. 相似文献