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81.
Most of the fibres that constitute the superior ovarian nerve (SON) originate at the neuronal bodies of the coeliac ganglion and innervate rat ovarian stroma cells. The purpose of this work was to study the part played by innervation on ovarian release of progesterone on day 15 and at the end of pregnancy in an integrated in vitro system known as the coeliac ganglion-SON-ovary system. We also investigated, in the same system, whether there is some kind of inter-relationship between the effect of adrenergic agents and LH on progesterone release on day 15 of pregnancy. The coeliac ganglion and the ovary were incubated in separate compartments, linked by the SON. The ovary was immersed in 2 ml buffer solution (ovarian compartment) and the coeliac ganglion was immersed in 2 ml of a different buffer solution (ganglion compartment). Under these conditions, the accumulation of progesterone in the ovarian compartment medium was used as an endpoint. Conditions were standardised on day 15 of pregnancy, when the decrease in the release of ovarian progesterone caused by non-specific stimulation on the ganglion with KCl (56 mM) demonstrated the functional integrity of the system. Neural influence was evaluated by the addition of adrenergic agents at a concentration of 10(-6)M to the coeliac ganglion. On day 15 of pregnancy, noradrenaline and propranolol increased progesterone release while phentolamine diminished it. The existence of ganglionic tone was assessed by analysing progesterone basal levels at different stages of pregnancy. The highest secretion of progesterone was found to take place on day 15, diminishing as pregnancy advanced. In addition, adrenergic neural participation was studied during the physiological luteolysis occurring at the end of pregnancy. Major findings were that noradrenaline increased ovarian accumulation of progesterone on day 19 and decreased it on day 20, while propranolol and phentolamine diminished progesterone release on both days. In additional studies, some neuroendocrine aspects were investigated at a peripheral level. The addition of LH only to the ovarian compartment did not affect progesterone secretion. However, when LH in the ovarian compartment was accompanied by noradrenaline, propranolol or phentolamine in the ganglion compartment, the release of progesterone decreased. It can be concluded that modifications of the neural state of the coeliac ganglion affect ovarian progesterone secretion and the physiology of pregnancy via the SON. The results may confirm that the coeliac ganglion-SON-ovary system provides a direct link between the autonomic nervous system and physiological events during pregnancy. 相似文献
82.
83.
NC de Bruin KA van Velthoven M de Ridder T Stijnen RE Juttmann HJ Degenhart HK Visser 《Archives of disease in childhood》1996,74(5):386-399
Data on body composition in conjunction with reference centiles are helpful in identifying the severity of growth and nutritional disorders in infancy and for evaluating the adequacy of treatment given during this important period of rapid growth. Total body fat (TBF) and fat-free mass (FFM) were estimated from total body electrical conductivity (TBEC) measurements in 423 healthy term Caucasian infants, aged 14-379 days. Cross sectional age, weight, and length related centile standards are presented for TBF and FFM. Centiles were calculated using Altman's method, based on polynomial regression and modelling of the residual variation. The TBF percentage steeply increased during the first half year of life, and slowly declined beyond this age. Various simple TBEC derived anthropometric prediction equations for TBF and FFM are available to be used in conjunction with these standards. Regression equations for the P50 and the residual SD, depending on age, weight, or length, are provided for constructing centile charts and calculating standard deviation scores. 相似文献
84.
85.
Leaf AN Wolf BC Kirkwood JM Haselow RE 《Medical oncology (Northwood, London, England)》2000,17(1):47-51
This study of etoposide in thyroid cancer was designed to determine the activity and toxicity of etoposide in a variety of
inoperable, thyroid hormone insensitive, and radio-iodine resistant primary cancers of the thyroid. The patients were required
to have an ECOG performance status of at least 3 and no previous exposure to chemotherapy. The etoposide was given at a dose
of 140 mg/m2 daily for 3 days and every 3 weeks until progression. The study was closed after 18 months because of poor accrual. There
were no responses seen among the 10 patients accrued. The toxicity was primarily hematologic. There was no evidence of activity
of etoposide in thyroid carcinoma, although this study lacked significant power because of the poor accrual. 相似文献
86.
Values of capillary refill time (CRT) were used for evaluation of skin microcirculation in the lower extremities severed by arteriosclerotic disease. The authors examined 133 extremities in 83 arteriosclerotic patients and 84 extremities of 50 healthy volunteers as a control group. To define the stage of the disease, walking distance, rest pain, level of arterial occlusion and the ankle/arm Doppler index (AAI) were considered. On each leg CRT was measured three times on the foot dorsum and pulp of the hallux. The mean value was calculated. The capillary refill index (CRI) was defined from the values of CRT as a proportion of compression time and time of skin recolouration. Twenty three extremities were examined before and after surgical treatment. The results suggest that values of CRI lower than 0.80 may be considered pathological. In advanced forms of the disease, low values of CRI were found in a significant number of extremities (p less than 0.01). A correlation was found among AAI, walking distance and CRI (r = 0.50). An extremely low CRI (under 0.55) was found on extremities without palpable femoral pulsations. After operation, a significant increase of CRI was observed (p less than 0.01). 相似文献
87.
88.
Neural networks in ventilation-perfusion imaging 总被引:2,自引:0,他引:2
89.
90.
INGEGERD MEJÀRE HANS-GÖRAN GRÖNDAHL KERSTIN CARLSTEDT ANN-CHRISTIN GREVER EVA OTTOSSON 《European journal of oral sciences》1985,93(2):178-184
In 63 teenagers the proximal surfaces of premolars to be extracted for orthodontic reasons and the adjacent surfaces of neighboring teeth, 598 surfaces in all, were examined radiographically and by probing. Direct inspection after extraction revealed that 51% of the surfaces had incipient carious lesions and 5% lesions with cavities. Of the surfaces with cavities 82.1% were correctly diagnosed radiographically if any radiolucency, regardless of its extent, was used as a diagnostic criterion. However, this yielded a false positive rate of 19.6%. If only radioluccncies extending at least into the inner third of the enamel were called positive the true positive rate was 36.7% and the associated false positive rate 1.6%. At a 5% cavity frequency the predictive positive values were 17% and 53%, respectively. Probing yielded a true positive rate of about 29% and a false positive rate of 1.1% with a predictive positive value of 50-57%. All radiolucencies extending into the dentin were associated with cavities. When the most liberal radiographic criterion was used 37.5% of all carious lesions, whether associated with a cavity or not, were detected and 3.8% of sound surfaces were falsely called carious. The corresponding predictive positive value at the actual rate of incipient lesions and lesions with cavities was 92.6%. 相似文献