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DNA dependent RNA asynthesis in inhibited by basic proteins like histones or polylysine This inhibitory effect is found to be suppressed by phosvitin, which is a phosphoprotein. Turbidometric studies indicate that polylysine interacts with DNA and RNA stoichiometrically. This interaction with DNA has been thought to be the cause of this inhibitory effect. Phovitin also interacts with polylysine more effectively than DNA. Phosvitin in quantities much less than the stoichionietric amount can compete with DNA for the polylysine and can thus make DNA free and available as template for the RNA synthesis. Phosphoserine, unlike pbosvitin, is ineffective in suppressing the inhibitory effect of polylysine. 相似文献
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Prior studies have produced conflicting results about whether a change in electric potential occurs at the time of ovulation. This study was undertaken to determine whether the OvutronR, a digital voltmeter which displays the sign and magnitude of voltage measured when the index fingers are applied to the electrodes, would produce a mix in polarity, some positive and some negative voltages, with 5 consecutive measurements preceding ovulation. This device was used daily in 10 normally ovulating women to determine whether such a mix in polarity occurred during the menstrual cycle and its relationship to the corresponding daily measurements of luteinizing hormone, total immunoreactive estrogen (IRE) and progesterone heralding and confirming ovulation. In addition, the Ovutron readings were compared to the basal body temperature (BBT) measurements. In 8 of 10 women studied with the Ovutron device, a mix in polarity was observed in 2 of 3 consecutive days preceding ovulation and was associated in all but 2 subjects with a 50 pg/ml/day incremental increase in IRE. By comparison, only 4 of the 10 subjects had a “classic” biphasic BBT curve. This novel device should be evaluated in a larger group of women employing these and other additional parameters (e.g., ultrasonography) in order to determine its efficacy and whether it has a role in the treatment of infertility as well as contraception. 相似文献
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Necrotizing infection of scrotum 总被引:2,自引:0,他引:2
Necrotizing infection of the scrotum (Fournier gangrene) rapidly spreads to adjacent skin with fever and toxemia and is life-threatening. Subcutaneous gas and a foul-smelling wet discharge from the skin are usually present. The infection is not cured with antibiotic therapy alone and requires immediate extensive debridement of all necrotic tissue. Repeated debridement each several days under general anesthesia is necessary until healthy granulation is present in the wound. Reconstruction with skin flaps or skin grafts shortens hospitalization and prevents the dense scar tissue and immobility of the tests that can occur with spontaneous epithelization. 相似文献
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S Biswas P Hindocha 《Clinica chimica acta; international journal of clinical chemistry》1974,51(3):285-289
Alkaline ribonuclease activity in 257 samples of sera obtained from 64 pregnant women in 19th to 42nd week of pregnancy was determined by a simple method. Pregnant women showed a significantly higher (15%, P < 0.02) activity than nonpregnant women of reproductive age. There is a gradual and significant increase in activity from weeks 10–20 to 21–30 and then to 31–42 of pregnancy. The pattern of enzyme level during weeks 10–42 of pregnancy does not show a continuous and regular increase as shown by enzymes and hormones of exclusively placental origin but is punctuated with many irregular rises and falls. Enzyme activities in a group of women showing complicated pregnancies were determined and compared with those found in normal pregnant women. 相似文献
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