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71.
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Very high dielectric constants have been observed for bacteria at low frequencies. High dielectric constants such as these can be explained by a theory which has been developed for the low-frequency dielectric dispersion of porous charged particles and which has been tested successfully through measurements with ion exchange resins. The bacterial cell wall is electrically similar to an ion exchange resin. Observations show that the theory provides a quantitative explanation for the low-frequency dielectric dispersion of bacteria.  相似文献   
73.
A simple and safe procedure has been described for the preparation of short-chain aliphatic hydroxamic acids in quantities as large as 1 mole and as small as 0.01 mole. The procedure is equally suitable for the preparation of isotopically labeled hydroxamates, as has been demonstrated in the case of 1-14C-acetohydroxamic acid and 3H-acetohydroxamic acid. Some physical and chemical characteristics, including infrared spectra of formo-, aceto-, propiono-, and isobutyro-hydroxamic acids prepared by this method have been described.  相似文献   
74.
When head and blunt abdominal injuries are combined, the head injury is often afforded too much attention and the abdominal injury too little, especially when the patient is unconscious. If mismanaged, the abdominal injury is often the more serious threat to life. Except for extradural hemorrhage, neurosurgical intervention, when indicated, can be delayed until the patient has been thoroughly evaluated for the presence of extra cranial injuries with higher therapeutic priority.Abdominal examination of the unconscious or uncooperative patient is difficult. Tenderness as a sign of abdominal injury cannot be elicited. Abdominal rigidity (in the absence of rigid extremities), a silent abdomen, shock, and extreme restlessness may indicate intra-abdominal changes. Abdominal paracentesis is a valuable diagnostic aid, and the finding of blood, bile-stained fluid, intestinal contents or air is an indication for immediate laparotomy. Once all injuries are known, priorities for treatment can be assigned. Often head and abdominal injuries can be treated concomitantly.  相似文献   
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Significant alterations in the structure and functions of the kidney are caused by a number of metabolic disturbances and deficiencies of physiological substances. These include intercapillary glomerulosclerosis, gout, hypercalcemia, hereditary cystinuria, potassium depletion, pyrophosphates deficiency, vitamin D deficiency and liver disorders. Some of these metabolic disorders are secondary to drug ingestion.  相似文献   
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A new macroscopic screening test for syphilis, the Latex-sts test, is extraordinarily simple. After inactivation of the patient''s serum for 30 minutes at 56°C the test is performed by mixing the patient''s serum with latex particles coated with cardiolipin and a protein fraction obtained from the non-pathogenic Reiter strain of Treponema pallidum. Two to three minutes after mixing, the result of the test is observed on a ringed serologic plate. The sensitivity, specificity and reproducibility of the new test are equivalent to those of the qualitative Venereal Disease Research Laboratory tube test. The advantages of the Latex-sts are that it can be done in a short time, it is simple and it requires a minimum of laboratory equipment. The coated latex particles are stable for 12 months.  相似文献   
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