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161.
162.
The method employs the domestic Wright stain for the staining of aspirated human bone marrow. Freshly distilled water, pH 6.0 to 6.4, is used. Wright stain, 0.5 cc, is placed upon the air-dried preparation and permitted to act for two minutes. The stain is then diluted with 2 cc. distilled water and permitted to act for from 5 to 10 minutes. After washing off the stain with distilled water, the preparation is placed into a decolorizer (acetone 0.5 cc, pure methyl alcohol 5.0 cc, and 100 cc. distilled water, pH 6.0 to 6.4) for differentiation from 1 to 5 seconds, rinsed, washed under running water and permitted to air-dry. A well stained and differentiated preparation shows the “Romanovsky effect”, and the sharpness of minute structures obtained compares favorably with control preparations stained with German dyes.

The bone marrow should be prepared as described. The Wright stain marketed by the National Aniline and Chemical Co., N. Y. was found to be reliable as regards staining quality of registered batches. One photomicrograph, showing bone marrow cells from pernicious anemia, is included.  相似文献   
163.
The cervical spine, usually regarded as a supporting structure for the head, is also an important viaduct of vessels and nerves which must function with little clearance in a congested and moving space bounded by bone. Pressure in this viaduct is an important cause of headache.The cervical foramina although apparently roomy, are constricted by cartilage, by the vertebral artery and its adnexae, and by the lateral intervertebral joints. Osteophytosis, swelling or adhesion in this constricted space almost inevitably causes painful vascular or neural disorder.In certain postures of the neck the vertebral artery is constricted or even occluded. Traction or sprain may likewise cause headache through disturbance of the vertebral arterial nerves, the posterior cervical autonomic system or the spinal accessory nerves which originate in delicate filaments from all points of the cervical spinal cord.A syndrome described by Skillern—migraine-like suboccipital and retro-orbital headache—is due to disturbance of the second cervical nerve, which communicates with the first division of the trigeminal nerve.Headache due apparently to a minor scalp contusion may really be due to irritation of a trigger area at the site of an old scalp injury.  相似文献   
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Ohne Zusammenfassung Vorgelegt in den Sitzungen der Akademie der Wissensehaften in Krakau im april und Juni 1917. Vgl. Vorl. Mitt. “Kernplasmarelation bei der Eireifung und in den ersten Entwicklungsphasen der Echinodermenkeime”. Bull. de l'Ac. des Sc. Cracovie 1917.  相似文献   
168.
Emil Dejdar 《Zoomorphology》1934,28(5):595-691
Ohne ZusammenfassungMit Unterstützung der Deutschen Gesellschaft der Wissenschaften and Künste für die Tschechoslowakische Republik.  相似文献   
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1. An optical system is described which furnishes an intensity of 282,000 meter candles at the bottom of a Warburg manometric vessel. With such a high intensity available it was possible to measure the rate of photosynthesis of single fronds of Cabomba caroliniana over a large range of intensities and CO2 concentrations. 2. The data obtained are described with high precision by the equation KI = p/(p 2 max.p 2)½ where p is the rate of photosynthesis at light intensity I, K is a constant which locates the curve on the I axis, and p max. is the asymptotic maximum rate of photosynthesis. With CO2 concentration substituted for I, this equation describes the data of photosynthesis for Cabomba, as a function of CO2 concentration. 3. The above equation also describes the data obtained by other investigators for photosynthesis as a function of intensity, and of CO2 concentration where external diffusion rate is not the limiting factor. This shows that for different species of green plants there is a fundamental similarity in kinetic properties and therefore probably in chemical mechanism. 4. A derivation of the above equation can be made in terms of half-order photochemical and Blackman reactions, with intensity and CO2 concentration entering as the first power, or if both sides of the equation are squared, the photochemical and Blackman reactions are first order and intensity and CO2 enter as the square. The presence of fractional exponents or intensity as the square suggests a complex reaction mechanism involving more than one photochemical reaction. This is consistent with the requirement of 4 quanta for the reduction of a CO2 molecule.  相似文献   
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