Asymmetric illumination contrast: a method of image formation for video light microscopy   总被引：4，自引：0，他引：4  

B Kachar 《Science (New York, N.Y.)》1985,227(4688):766-768

Images with high resolution and exceptionally broad gray scale can be obtained by the application of video contrast enhancement to an optimized procedure for imaging transparent objects with oblique rays of illumination. This technique is simple to set up. A conventional microscope with a light source whose position can be adjusted and a video camera with controls for gain and black level are the only essential components. Features such as high resolution, optical sectioning, control of contrast, and operation under low light intensity make this technique preferable, in several instances, to currently used video microscopy techniques.  相似文献   

In vitro studies of haemolysis by Leptospira interrogans serovars pomona and ballum   总被引：2，自引：0，他引：2  

J C Thompson  R B Marshall 《Veterinary microbiology》1986,11(3):285-292

Washed and unwashed red blood cells (RBC) from young calves, adult cattle, hamsters and humans were incubated with Leptospira interrogans serovars pomona and ballum. Washed cells suspended in saline were always haemolysed while unwashed cells and those which were washed and resuspended in plasma were never haemolysed, despite the presence of large numbers of organisms within the culture supernatant. Pomona produced greater haemolysis of cattle and human RBC than did ballum, but with hamster RBC ballum produced greater haemolysis than did pomona. A group of 6- to 9-month-old cattle infected with pomona showed no signs of clinical disease and RBC taken from them before infection and during the development of antibodies to pomona were haemolysed by pomona only after the cells were washed. Plasma therefore appears to have a protective function. This in vitro protective function of plasma even extended to plasma from young seronegative calves.  相似文献   

Polygalacturonase and β-galactosidase activities in Hayward kiwifruit as affected by light exposure,maturity stage and storage time     

S. Tavarini  E. Degl’Innocenti  D. Remorini  R. Massai  L. Guidi 《Scientia Horticulturae》2009

Softening process and total antioxidant activity were evaluated in kiwifruit differently exposed to light intensity and harvested at two different times (October 10 and November 14). Fruit was stored for 2 months at 0 °C (S1) and then maintained for a week at ambient temperature (S2). The results showed that fruit harvested later presented a faster softening rate during storage than fruit harvested earlier, even if antioxidant activity did not change. Light-exposed fruit showed higher flesh firmness than that of shaded ones. Polygalacturonase activity was higher in kiwifruit maintained for a week at ambient temperature after cool storage and, in particular the highest value was recorded in fruit harvested later. The behaviour of β-galactosidase was different: it did not show changes in fruit harvested later and significantly decreased in light- and shade-exposed fruit harvested earlier.  相似文献   

A NEW ESTROGENIC SUBSTANCE PRESENT IN THE NEUTRAL FRACTION OF HUMAN PREGNANCY URINE     

Dorfman RI 《Science (New York, N.Y.)》1940,92(2399):585-586

In addition to the well-defined phenolic estrogens in human pregnancy urine there appears to be another estrogenic substance which is a neutral non-ketonic compound.  相似文献   

THREE CASES OF MALE INFERTILITY     

W. L. Hindmarsh  B.V.Sc  M.R.C.V.S.  D.V.H. 《Australian veterinary journal》1941,17(1):21-23

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THE WORK OF OCTAVE HALLAUER     

Thurston RH 《Science (New York, N.Y.)》1884,4(86):306-308

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Qtmas über die R. bader. Forftmärter     

R. 《European Journal of Forest Research》1865,9(1):384-387

Ohne Zusammenfassung  相似文献   

MAGAZINE ENTOMOLOGY     

Smith JB 《Science (New York, N.Y.)》1901,14(351):456-457

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ALTERATIONS OF TISSUE CELLS IN THE BLOOD STREAM     

Isaacs R 《Science (New York, N.Y.)》1928,68(1770):547-548

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Zur Taxonomie einiger wirtschaftlich wichtiger Drahtwürmer     

B. Schaerffenberg 《Journal of pest science》1940,16(6):61-63

Ohne Zusammenfassung Mit 7 Abbildungen  相似文献