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11.
The renal venous outflow of dopamine and noradrenaline were studied in the canine kidney in situ in connection with renal nerve stimulation (RNS). RNS (0.5-4 Hz) caused frequency-dependent increases in the outflow of both catecholamines, which could be detected already at 0.5 Hz. The ratio dopamine/noradrenaline in renal venous plasma (approximately 0.15) was not influenced by varying the RNS parameters but was significantly enhanced (to about 0.25) by pretreatment with guanethidine according to a procedure previously used to demonstrate renal dopaminergic vasodilatation. The unstimulated kidney removed conjugated dopamine (which represents 98–99% of the total dopamine in plasma). During RNS the conjugated dopamine outflow to renal venous blood increased, but measurements of conjugated dopamine were less reliable than measurements of free dopamine to assess dopamine release from the kidney. When studying the renal nerve contributions to the renal venous outflow of dopamine and noradrenaline more accurate estimates may be obtained by correcting for the removal of catecholamines delivered to the kidney in arterial plasma. Such corrections were performed with endogenous adrenaline or radiolabelled noradrenaline. The two methods of correction yielded similar results and showed that RNS reduced catecholamine extraction in the kidney. The high ratio of dopamine/noradrenaline in kidney tissue (with a preferential distribution of dopamine to the cortex) and the dopamine outflow to renal venous plasma during RNS support the existence of specific dopaminergic nerves in the dog kidney.  相似文献   
12.
Intranasal betamethasone valerate in the treatment of seasonal rhinitis   总被引:1,自引:0,他引:1  
Betamethasone valerate aerosol given in doses of 100 μg into each nostril twice daily was compared with a placebo in a double-blind, cross-over trial involving thirty patients with seasonal rhinitis. Patients recorded symptoms of eye irritation and watering, sneezing, rhinorrhoea, and nasal blockage, on a diary card. Analysis of the symptom scores showed that nasal symptoms were significantly better on betamethasone valerate than on placebo (P<0.01) and that nasal blockage in particular was improved (P<0.001). The patients’preference was significantly in favour of the active compound (P < 0.02) and no side-effects were noted. It is concluded that betamethasone valerate offers a safe and effective form of treatment for seasonal rhinitis.  相似文献   
13.
Abstract. Recent reports indicate that the group B haemolytic streptococcus has now assumed a major role in neonatal septicaemia in the United Kingdom. Of particular concern are the absence of premonitory signs, the fulminating nature of the infection and the high mortality. 31 cases from which this organism was isolated during the first week of life included 5 cases of neonatal septicaemia, 4 of which proved fatal. An attempt was made ( a ) to identify the group of neonates at greatest risk and ( b ) to formulate guidelines for early detection and treatment. Study indicates the importance of apnoea as a sign of infection particularly in those infants who are preterm, of low birth weight and asphyxiated. There is need for aggressive bacteriological screening and early administration of antibiotics to prevent the high mortality from group B streptococcal infection.  相似文献   
14.
Summary. Eighteen patients whose only demonstrable cause of infertility was a minor degree of endometriosis and whose partners were normal, were investigated prospectively for one menstrual cycle using ultrasonography and endocrine profiles. Twelve cycles appeared to be normal. A luteinized unruptured follicle (LUF) occurred in two cycles and one patient had a follicular cyst. In a further two patients there was inadequate or abnormal folliculogenesis whilst in the last patient the follicle ruptured prematurely. This study describes the variety of endocrinological abnormalities found in women with mild endometriosis, and concludes that, in this series at least, there is a low frequency of LUF.  相似文献   
15.
BACKGROUND: The physical-chemical properties of perfluorochemical (PFC) liquids have been shown to influence physiological and cellular responses during partial liquid ventilation (PLV). The aim of this study is to compare the relationship between patho-physiological endpoints and the physical properties of three PFC liquids used in treating acute lung injury. METHODS: A total of 18 juvenile rabbits were randomized into conventional mechanical ventilation or PLV groups after lung saline lavages. Three PFC liquids, including Flutec perfluoro-1,3,5-trimethylcyclohexane (PP4; vapor pressure, 28.8 mmHg at 37 degrees C), Perfluorodecalin (PFD; vapor pressure, 13.6 mmHg at 37 degrees C), and Perflubron (PFB; vapor pressure, 10.4 mmHg at 37 degrees C) were used for PLV with no replacement for 4 h. A thermal detector was used to measure PFC loss rate. Physiological measurements and evaporative loss rate of PFC were done every 30 min, and lung histology was examined. RESULTS: The mean evaporative loss rate was significantly higher in the PP4 group (4.75 +/- 0.24 mL/kg per h) than in either the PFD (1.43 +/- 0.11 mL/kg per h) or the PFB (1.18 +/- 0.05 mL/kg per h) group (P < 0.05). The oxygenation of PFD and PFB was maintained good for 4 h, however, the PP4 group showed a fast deterioration since 2 h post-treatment due to fast dropping of the residual PP4 amount in lungs. Histology showed good alveolar integrity in the PFD and PFB groups. CONCLUSIONS: The effects of PLV are directly influenced by the evaporative property of the PFC liquid. With no replacement over 4 h, PLV effects could be maintained with utilizing a PFC liquid with low, rather than high, vapor pressure. PFC with high vapor pressure has a high loss rate and low residual volume that causes poor maintenance on oxygenation during PLV. Therefore, measuring PFC loss rate is important in future studies and clinical application of PLV.  相似文献   
16.
Serum CA125 concentrations measured before and during chemotherapy may provide additional information for prognostic assessment of patients with epithelial ovarian cancer (EOC), and enable discrimination between patients who are likely to benefit from further therapy and those who will not. Medical records of 40 patients with advanced EOC, treated at the Department of Obstetrics and Gynecology of the University Hospital Nijmegen between July 1984 and April 1993, were examined. All patients had primary cytoreductive surgery followed by platinum-based chemotherapy. Serum samples were obtained before surgery and during chemotherapy. Follow-up information and patient and tumor characteristics were abstracted from medical records until December 1, 1994. By using multivariate Cox proportional hazards models for disease-free and overall survival it was evaluated whether outcome prediction was improved by inclusion of serum CA125 quantitations.
  Only FIGO stage and extent of residual tumor were significant independent prognostic factors before the start of chemotherapy. When such regression models were constructed after subsequent courses of chemotherapy, serum CA125 measurements conducted after each of the first three chemotherapy courses improved the prediction of disease-free survival. Prediction of overall survival was improved by inclusion of serum CA125 measurements after courses 1–6. Inclusion of serum CA125 measurements during chemotherapy improved prognostic assessment of patients with advanced EOC.  相似文献   
17.
The policy and health service background to this discussion are the radical changes in cancer services currently underway in the wake of the Calman-Hine Report and the wider changes ushered in by the NHS and Community Care Act 1990 (UK). Using the changing face of hospice care as the focus, the authors explore some of the potential issues and dilemmas involved in providing supportive care for cancer patients and their families. Three 'themes', or areas of concern, are highlighted: links between services, changing organizational factors, and increasing 'medical imperialism'. Potential benefits and drawbacks of the changing ethos and organizational structures are discussed. Interview data are used as 'triggers' for the presentation of the authors' own reflections on developments in the hospice and cancer services' arenas. The paper draws on interview data collected in the pilot phase of a 3-year study on the psycho-social needs of cancer patients and their informal carers in north-west England. Twenty-nine interviews were conducted with a range of professionals involved in the provision of cancer services in Lancaster and Kendal. In the spirit of 'gathering thoughts' and facilitating debate, a commentary on developments in the hospice sector is offered rather than any firm conclusion.  相似文献   
18.
Methadone levels and neonatal withdrawal   总被引:1,自引:0,他引:1  
The purpose of this study was to observe the effects of methadone exposure in utero, with special reference to maternal and neonatal methadone concentrations and neonatal withdrawal. Two groups of mother-infant pairs were studied. In the first group, serum methadone concentrations were determined in infants at 1, 6 and 24 h after delivery. In the second group, blood was obtained at 24, 48, 72 and 96 h after birth. There was no correlation between neonatal serum levels and the intensity of withdrawal symptoms. There was no relationship between maternal methadone dose at delivery or maternal serum levels and neonatal methadone levels. The results of this study may be complicated by the prenatal exposure of the neonates to other drugs of abuse apart from methadone.  相似文献   
19.
Summary. The clinical and endocrine effects of progestogen therapy in early pregnancy were investigated using a double-blind randomized trial in 64 patients who had a viable fetus at 6 weeks gestation and had an increased risk of miscarriage. The patients were randomly allocated to receive either 17 alpha-hydroxyprogesterone caproate or a placebo between 7 and 12 weeks gestation. Four fetal ultrasonographic variables and 17 maternal endocrine variables were studied in each woman. Only four maternal serum variables (17 alpha-hydroxyprogesterone, prolactin, thyroxin and thyroxin binding globulin) rose significantly. The serum progesterone levels in the hormone supplemented group were on average 20% higher than in the placebo group but the difference was not statistically significant. However, the relation between the progesterone levels and the fetal outcome was not clear. Therefore it is not advisable to prescribe 17-OHP-C during early pregnancy to prevent a miscarriage.  相似文献   
20.
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