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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
TODD F. HEATHERTON LYNN T. KOZLOWSKI RICHARD C. FRECKER KARL-OLOV FAGERSTROM 《Addiction (Abingdon, England)》1991,86(9):1119-1127
We examine and refine the Fagerström Tolerance Questionnaire (FTQ; Fagerström, 1978). The relation between each FTQ item and biochemical measures of heaviness of smoking was examined in 254 smokers. We found that the nicotine rating item and the inhalation item were unrelated to any of our biochemical measures and these two items were primary contributors to psychometric deficiencies in the FTQ. We also found that a revised scoring of time to the first cigarette of the day (TTF) and number of cigarettes smoked per day (CPD) improved the scale. We present a revision of the FTQ: the Fagerström Test for Nicotine Dependence (FTND). 相似文献
992.
Using fura-2 loaded neural tumour cells, SK-N-SH, we demonstrate that receptor-mediated activation of phosphoinositide hydrolysis not only causes the release of Ca2+ from intracellular stores but also causes a concomitant influx of extracellular Ca2+. Thapsigargin (TG), a sesquiterpene lactone, causes a sustained elevation of intracellular Ca2+ and depletion of the inositol 1, 4, 5-trisphosphate-sensitive intracellular Ca2+ stores. In the absence of extracellular Ca2+, the increase in intracellular Ca2+ concentration ([Ca2+]i) was transient, suggesting that thapsigargin activates both intracellular mobilization and the influx of Ca2+ from extracellular space. These results are consistent with the proposal that the depletion of the inositol 1, 4, 5-trisphosphate-sensitive intracellular Ca2+ pool serves as a signal for Ca2+ influx. 相似文献
993.
Bilateral porencephalic defect in a newborn after injection of benzol during pregnancy 总被引:2,自引:0,他引:2
Porencephaly is usually considered to be a prenatal brain lesion due to a circulatory failure. We report a case of bilateral porencephaly with heterotopia and absence of the septum pellucidum in a newborn. The mother had received several injections of benzol during pregnancy with an intent of inducing abortion. The possibility of a causal relationship between the administration of benzol and the occurrence of the defect is supported by the existence of previously reported cases of cerebral malformations following maternal exposure to organic solvents. 相似文献
994.
995.
Twenty patients with sympathetic maintained pain (SMP) underwent surgery to treat an associated nerve injury. In each patient, an axillary catheter technique was used to maintain anesthesia and sympatholysis for up to 4 days following surgery. In no instance was the SMP exacerbated by the operation. The use of prolonged sympathetic blockade as an adjunct increases the margin of safety in surgery for these patients when nonoperative measures cannot relieve the pain or restore function. 相似文献
996.
M. S. Bornman J. M. C. Oosthuizen H. C. Barnard G. W. Schulenburg D. Boomker and S. Reif 《Andrologia》1989,21(5):483-485
Several substances can interfere with microtubular function eg. colchicine. Melatonin, a hormone secreted by the pineal gland has similar effects as colchicine on microtubules. In this study melatonin levels were determined in both plasma and seminal plasma of patients with good or impaired motility and forward progression. There was no statistically significant difference between the mean plasma and seminal plasma values of patients with good or impaired motility and forward progression. There was no correlation between seminal plasma melatonin and impaired motility or any other semen parameter. There was also no correlation between plasma and seminal plasma concentrations of melatonin. High seminal plasma melatonin concentrations were not necessarily associated with impaired sperm motility. From these it is concluded that seminal plasma melatonin plays no important role in sperm motility. 相似文献
997.
Contributions of ovarian failure and aging to blood pressure in normotensive perimenopausal women: a mixed longitudinal study 总被引:1,自引:0,他引:1
Epidemiologic studies have shown that blood pressure increases more rapidly in middle-aged women than in middle-aged men. Whether or not ovarian failure contributes to this rapid rise is still not clear. In a follow-up study begun in 1979 and to continue for 10 years, the blood pressure of 193 healthy normotensive perimenopausal women, who lived in the mixed rural/industrial community of Ede, the Netherlands and who were initially aged between 49 and 56 years, was measured annually. During the course of the study, the onset of menopause of each participant could be established. Because of the mixed longitudinal design of the study, it was possible to evaluate the effects of both chronologic aging and time pre- or postmenopause on blood pressure. After the first seven years of follow-up, it was demonstrated that blood pressure did not increase in 168 women whose body weight was relatively stable. After multivariate analyses, systolic as well as diastolic pressure showed a significant negative relation (slope, 1.34 mmHg per year and 0.63 mmHg per year, respectively) with the years since menopause. On the other hand, the observed positive relation (slope, 0.81 mmHg per year) of systolic pressure with chronologic aging was not significant. No consistent association was found between diastolic pressure and chronologic aging. It is concluded that menopause cannot be regarded as a cause of hypertension; on the contrary, ovarian failure appears to have a protective effect on the increase in blood pressure as a result of chronologic aging. on the increase in blood pressure as a result of chronologic aging. 相似文献
998.
999.
Ocular motor and manual tracking in Parkinson''s disease and the effect of treatment. 总被引:1,自引:1,他引:0 下载免费PDF全文
J M Gibson R Pimlott C Kennard 《Journal of neurology, neurosurgery, and psychiatry》1987,50(7):853-860
A quantitative analysis of unpredictable saccadic and smooth pursuit ocular motor and manual tracking was performed in 15 mildly affected, previously untreated subjects suffering from Parkinson's disease and in age-matched normal controls. The patients' ocular saccades were characterised by an increased variability of their latencies and reduced accuracy, with normal velocity profiles apart from saccadic duration. Their smooth pursuit had a decreased velocity gain. Similar abnormalities were found with manual tracking. Clinical improvement with dopaminergic drugs was associated with an improvement of saccadic accuracy and smooth pursuit gain. It is postulated that the ocular motor changes seen in Parkinson's disease are contingent upon functional dopamine levels in the basal ganglia. 相似文献
1000.
Changing glial organization relates to changing fiber order in the developing optic nerve of ferrets
The structures of the developing eye-stalk and the relationships of early retinofugal fibers as they pass through the stalk, chiasm, and tract have been studied by light and electron microscopical methods in fetal ferrets aged 23–27 days. The early eye-stalk can be divided into two parts: a narrow extracranial part has a narrow lumen and is lined by few cells, whereas a thicker intracranial part has a wider lumen and is lined by several rows of cells. At the earliest stages no axon bundles are recognizable in the stalk, but fibers of the supraoptic commissure are already beginning to cross the midline in the diencephalon. Subsequently, as retinofugal axons invade the stalk, the glia of the extracranial part of the stalk have an interfascicular distribution and axon bundles are separately encircled by glial cytoplasm. In the intracranial part, as in the chiasm and tract, the glial cells occupy a periventricular position and send slender radial cytoplasmic processes to the subpial surface; these pass between groups of axons that here lie immediately deep to the subpial glia. Whereas axonal growth cones have no evident preferred distribution in the extracranial stalk, they tend to accumulate near the pial surface intracranially. The boundary between the two types of organization shifts as development proceeds so that the interfascicular glial structure of the early extracranial stalk first encroaches upon the intracranial parts and later appears in the chiasm. The characteristic adult arrangement of fibers in an age-related order in the optic chiasm and tract, but not in the optic nerve, can be understood if axonal growth cones are guided toward the pial surface by radial glia but not by interfascicular glia. From the distribution of the growth cones, this is what appears to happen. 相似文献