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991.
Henry B. Kirkland 《American heart journal》1932,7(3):360-370
A fatal case of gonococcus endocarditis with detailed autopsy findings is reported. Acute endocarditis followed a urethritis and affected an aortic valve which was already damaged by rheumatism.In addition to acute vegetative endocarditis of the aortic valve, autopsy revealed chronic productive changes in both mitral and aortic valves, subendocardial abscess with extension to the pericardium, diffuse suppurative and hemorrhagic pericarditis, acute intracapillary glomerular nephritis, acute focal interstitial nephritis, parenchymatous degeneration of the kidneys, infarction and suppuration of the spleen, degeneration and congestion of the liver, suppurative gastritis, pulmonary congestion, bilateral hydrothorax, ascites, conjunctival petechiae, suppurative leptomeningitis, gangrene of the legs, and a decubitus ulcer. 相似文献
992.
Hideyo Noguchi Henry R. Muller Evelyn B. Tilden Joseph R. Tyler 《The Journal of experimental medicine》1929,50(4):455-461
In the experiments here reported, definite verruga lesions, in which the presence of Bartonella bacilliformis was established by culture or by passage to rhesus monkeys, were produced in a dog and in a donkey by inoculation of cultures or monkey passage strains. The reaction induced in these animals was entirely local, however; blood cultures were sterile. Histologically, the lesions produced were similar to those obtained in monkeys by inoculation of Bartonella bacilliformis, except for the presence of a marked polynuclear leucocytic exudate. In another donkey a lesion histologically suggestive of verruga was produced, while in one donkey and a horse the results of inoculation were negative or indefinite. The intravenous injection of a filtrate or of heat-killed cultures of Bartonella bacilliformis into two donkeys was followed by the appearance of large, soft, subcutaneous swellings, on various parts of the body, not resembling in any way verruga lesions. 相似文献
993.
Henry T. Chickering 《The Journal of experimental medicine》1915,22(2):248-268
1. The protective substances contained in specific precipitates from antipneumococcus serum can be extracted by suitable chemical and physical agents, dilute sodium carbonate at 42°C. being especially advantageous as an extractive agent. 2. The resulting water-clear extracts, when made up to the original volume of the serum used for precipitation, protect animals almost as well as does the whole serum. 3. The bacterial extracts used in precipitating the protective substances from the serum act specifically; that is, a bacterial extract of pneumococcus of Type I removes the protective substances from a Type I immune serum only. 4. In a polyvalent serum of Type I and Type II, the protective substances of each type may be removed independently of each other by the successive addition of the homologous antigens. 5. Extracts of specific serum precipitates contain only one-fiftieth to one-sixtieth of the protein in the original serum, and about one-half the protein of the whole precipitate. 6. Extracts contain not only protective substances but agglutinins and precipitins. 7. Extracts and whole precipitates not only confer passive immunity but stimulate the production of active immunity to pneumococcus infection in rabbits and mice. 相似文献
994.
INFLUENZA : II. EFFECT OF INFLUENZA VIRUS MULTIPLICATION ON THE OXYGEN CONSUMPTION CURVES OF EMBRYONATED EGGS INCUBATED AT DIFFERENT TEMPERATURES
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Henry Pinkerton Donald Greiff Herman T. Blumenthal Richard Hensley 《The Journal of experimental medicine》1950,91(3):331-334
In addition to the cycles of growth shown by the influenza A virus during the first 24 hours of its residence in the fertile egg, cycles separated by longer time intervals have been noted between the 24th and 96th hours. These longer cycles are best seen when the eggs are incubated at 40°C. Corresponding fairly accurately with these cycles of growth of the virus, wide cyclic variations in the rates of increase in oxygen consumption of the infected eggs have been found to occur. These variations are in striking contrast to the uniformity of increase noted in uninfected eggs. The variations in infectivity may be caused by periodic interference with virus multiplication by accumulated inactive virus particles. The variations in oxygen consumption probably are correlated with variations in the concentration of virus toxins. 相似文献
995.
Characteristic striations form in the dentin of rats maintained on a diet deficient in magnesium. These striations were studied histochemically in both intact and parathyroidectomized rats. In the lower incisor teeth the striations occurred at intervals varying between 20 and 27μ. Each dentinal striation contained distinct zones of sudanophilic material, acid mucopolysaccharides, and PASpositive proteinpolysaccharides. Dentinal tubules appeared to be enlarged in the zone of sudanophilia. Striations in the dentin of parathyroidectomized rats were very similar to those in intact animals. Formation of dentinal striations ceased within 4 days when deficient animals were placed on a magnesium-supplemented diet. 相似文献
996.
997.
998.
Injected intracranially in the dba strain of mice, murine typhus rickettsiae caused a serially transmissible meningoencephalitis similar to that produced by psittacosis and certain other viruses. All injected mice of this strain suddenly became ill and approximately half of these animals died on the 5th and 6th days after injection. Swiss mice injected in parallel series showed illness in only a few animals, and no deaths occurred. These experiments were carried out at room temperatures ranging from 60–80°F. After intraperitoneal injection, a uniformly fatal rickettsial peritonitis developed in all dba mice kept at environmental temperatures of 65–73°F. or 70–80°F. Death occurred between the 3rd and 7th days after injection, depending somewhat on the dosage used. Among Swiss, brown agouti, and A albino mice injected in parallel series, the mortality was less than 60 per cent. These experiments indicate that mice of the dba strain are much more susceptible to murine typhus than are mice of the other three strains studied. 相似文献
999.
1. Studies have been made of the behavior of renal blood flow after partial constriction of the renal artery in twenty-four dogs. 2. When reduction in renal blood flow is produced by partial constriction of the renal artery, a readjustment of flow in the direction of normal occurs within a few minutes, subsequent constriction being again followed by a return of flow toward normal until the artery is markedly constricted. 3. Renal blood flow after marked constriction of the artery becomes extremely susceptible to the vasoconstrictive action of small doses of adrenalin, and flow may cease with larger doses for a considerable period of time. 4. Arterial hypertension of significant degree may follow partial constriction of one renal artery during brief experiments when adrenalin in addition has been administered. 5. Further evidence is presented in favor of the concept that the renal circulation enjoys a control independent of systemic arterial pressure. 相似文献
1000.
The size of the heart was ascertained at necropsy or by roentgenologic examination in 100 consecutive cases of typical bundle branch block.The clinical diagnoses were: arteriosclerotic heart disease, 58 per cent; coronary artery occlusion, 25 per cent; chronic rheumatic valvular disease, 9 per cent; and miscellaneous conditions, 8 per cent.The heart was enlarged in all cases in which it was examined post mortem; the average cardiac weight was 586 Gm., the lowest, 375 Gm.Of the cases in which there was only a roentgenographic examination, the heart was increased in size in 91 per cent. In three of the six cases in which there was no enlargement, the diagnosis was Graves' disease.Left bundle branch block was present in 90 per cent of the cases. In 71 per cent of these the left ventricle was larger than the right, and in none was the right ventricle preponderant. Hypertensive heart disease was almost invariably associated with left bundle branch block.Of the ten cases of right bundle branch block, the right ventricle was predominant in four, and the left ventricle in one. Both ventricles were enlarged in five cases of coronary artery occlusion.Diffuse myocardial involvement was found in all cases in which a necropsy was performed.It is concluded that, in most instances, chronic bundle branch block is the result of an increase in the size of the heart, and of myocardial damage, with diffuse involvement of the bundle branch system. The type of bundle branch block depends on which ventricle is predominantly enlarged. 相似文献