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161.
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A prospective study was performed to determine the incidence of group B streptococci cultured from the cervix in a series of obstetric clinic patients at St. Margaret's Hospital. Cultures were taken during each trimester and planted to both a blood agar plate and a selective broth medium. Of a total of 812 cultures, 18 were positive, an over-all incidence of 2.2 per cent. During the first, second, and third trimesters, 2.2 per cent, 2.5 per cent, and 1.9 per cent of cultures were positive, respectively. Women with positive cultures were treated with a 10 day course of oral penicillin or a suitable alternative; four of 16 had persistent positive cultures at the end of the first treatment period, three of these four responded to a second course of antibiotics, and the remaining patient responded after a third treatment course. The total number of positive cultures by selective broth was 24, compared to nine in blood agar, indicating a 2.7-fold increase in pickup by the selective broth. 相似文献
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Two simple chromenes with anti-JH activity have been isolated and identified from the bedding plant Ageratum houstoianum. By contact and fumigation these compounds induce precocious metamorphosis and sterilization in several hemipteran species of insects. Certain holometabolous species are sterilized, forced into diapause, or both. Each of these biological actions is equivalent to removal of the corpora allata, which produce the JH's, and is reversible by treatment with exogenous JH. Thus, the action of these compounds is to stop the production or depress the titer of the JH's. To our knowledge, this is the first discovery of anti-JH, and we hope it will guide the way to the emergence of a fourth generation of safe and insect-specific pesticides. 相似文献
166.
The effect of 57 days of moderate physical activity on the energy intake and balance of three obese women (187% of ideal weight) was investigated in a metabolic balance study. Food was offered in extra quantity, prepared in a palatable but simple fashion, and intake was covertly monitored. Expenditure was measured using the factorial method and indirect calorimetry done every 3 to 4 days. After a 5-day evaluation phase which no exercise was done, individual treadmill assignments were given to subjects to increase daily expenditure to 125% of sedentary levels. Mean dialy intake (1903 kcal/day) and expenditure (2882 kcal/day) did not change with time. As a result, negative energy balance was obtained and sustained. A consistent rate of weight loss (0.12 kg/day) at a reasonable cost (8200 kcal/kg)occurred. Therefore, obese women doing long-term moderate exercise do not compensate by an increase in caloric intake. This can produce a negative caloric balance when exercise is coupled with ad libitum selection of ordinary foods. 相似文献
167.
The acute effects of amitriptyline, iprindole and trazodone on blood pressure and heart rate in rats
The cardiovascular effects of the tricyclic anti-depressant amitriptyline, a monoamine uptake inhibitor, and iprindole and trazodone, two novel anti-depressants of unknown mechanism, were monitored in urethane anesthetized rats following intravenous (IV) or intracerebroventricular (IVT) injection. Amitriptyline (2 mg IV or 0.25 mg IVT) produced hypotension that might reflect an action of norepinephrine on the anterior hypothalamus. Iprindole (2 mg IV) produced hypertension and (0.25 mg IVT) tachycardia that is consistent with a partial beta-agonist mechanism. Trazodone (1 mg IV or 0.25 mg IVT) produced hypotension and bradycardia that is consistent with the activation of noradrenergic neurons in the anterior hypothalamus perhaps as a result of trazodone acting on presynaptic alpha 2 receptors or on presynaptic serotonin receptors to increase the release of norepinephrine. All three of these anti-depressants have the potential to precipitate cardiovascular complications, particularly in patients with pre-existing cardiovascular abnormalities. 相似文献
168.
Thyroid carcinoma after high-dose external radiotherapy for Hodgkin's disease: report of three cases
IR McDougall CN Coleman JS Burke W Saunders HS Kaplan 《Canadian Metallurgical Quarterly》1980,45(8):2056-2060
Three patients (two female and one male), who had received mantle irradiation for Hodgkin's disease eight, ten, and twelve years previously, developed papillary thyroid carcinoma. The radiation doses to the necks overlying the site of thyroid cancers were 3000, 4000, and 4100 rads, respectively. It has been stated that there is no risk of developing thyroid cancer with such high doses of external irradiation but apparently this complication will be encountered in a small number of patients. 相似文献
169.
It was shown that the cm and Lg genes, which are relatively closely linked, are not linked with markers in any of the four established linkage groups in the Syrian hamster. Therefore, the linkage between these two genes constitutes a new linkage group, LGV. 相似文献
170.