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71.
Beta2- and alpha2-adrenergic receptors (AR) are thought to be the main AR subtypes to exert the effects of catecholamines on the immune system. However, in the present study, we demonstrate that another subtype of AR can be induced in human monocytes. Expression of alpha1b- and alpha1d-AR mRNA can be obtained by culturing freshly isolated human peripheral blood monocytes with the neuroendocrine mediators dexamethasone or the beta2-AR agonist terbutaline. Using the human monocytic cell line THP-1, we demonstrate that increased levels of alpha1b- and alpha1d-mRNA are accompanied by increased levels of receptor protein as determined by Western blot analysis and radioligand binding assays. This study describes for the first time regulated expression of alpha1-AR subtypes in human monocytes.  相似文献   
72.
AIMS: To describe two phenotypic variations of autosomal recessive retinal dystrophy occurring in a consanguineous family in a pseudodominant pattern, resulting from mutations in the ATP binding cassette transporter (ABCR) gene. METHODS: Patients of this family underwent an extensive ophthalmic evaluation, including fundus photography, fluorescein angiography, and electroretinography (ERG). Genetic analysis comprised sequence analysis of the retina specific ABCR gene. RESULTS: Five patients presented with decreased visual acuity in the second decade, central chorioretinal atrophy associated with a central scotoma, and severely decreased photopic and scotopic ERG responses. This clinical picture, which in our opinion resembles a cone-rod dystrophy (CRD), was associated with compound heterozygosity for IVS30+ 1g -->t and IVS40+5g-->a mutations in the ABCR gene. The four remaining patients presented with night blindness in the first decade because of a retinitis pigmentosa-like (RP-like) dystrophy. In addition to a pale "waxy" optic disc, attenuated retinal vessels and bone spicule deposits, a widespread chorioretinal atrophy was observed. The scotopic ERG was extinguished and the photopic ERG was severely diminished. Genetic analysis revealed a homozygous 5' splice mutation IVS30+1g -->t in the ABCR gene. CONCLUSION: Mutations in the ABCR gene can cause clinical pictures resembling autosomal recessive RP and autosomal recessive CRD.  相似文献   
73.
Objective: This study investigated the relative value of adverse drug events reported by doctors, nurses and patients. Methods: The study was conducted on a total of four wards: the paediatric and internal medicine wards (including geriatric patients) of two peripheral hospitals in the Netherlands. Adverse drug events were collected by spontaneous reporting (doctor and nurse reports) and by daily ward visits, during which the patients were interviewed by a hospital pharmacist (patient reports). Criteria for relative value of the reported adverse drug events were the number of potentially serious reactions, the number of reactions not mentioned in the patient information leaflet and the number of reactions reported to new drugs (5 years or less on the Dutch market). No formal causality assessment was applied. Results: Over a period of 2 months in 1996 (Hospital I) and 2 months in 1997 (Hospital II) a total of 620 patients were included in the study and adverse drug events were reported in 179 (29%) of these cases. Doctors reported a statistically significant larger number of serious (26% of all doctor reports; odds ratio (OR) 3.2; confidence interval (CI) 1.2–8.7) and unknown (39%; OR 2.5; CI 1.0–6.0) adverse drug events than patients themselves during the daily ward visit. Doctors also reported more serious and unknown adverse drug events than nurses. Adverse reactions to new drugs were reported during the daily ward visit only (8% of all daily ward visit reports). Conclusion: This study reconfirms that doctors are the main source for reports of serious and unknown adverse drug events in hospitalized patients. However, patients themselves seem to report more adverse reactions to new drugs (during the daily ward visit). By focusing on patients using new drugs, the daily ward visit might become cost-effective. This needs to be explored in future studies. Received: 10 September 1998 / Accepted in revised form: 30 November 1998  相似文献   
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Hepatitis and solid organ transplantation   总被引:3,自引:0,他引:3  
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77.
Diwan  BA; Anderson  LM; Ward  JM 《Carcinogenesis》1997,18(10):2009-2014
Tamoxifen (TAM) is widely used as adjuvant breast cancer therapy after surgery and as a chemopreventive agent in women of child-bearing age. However, TAM therapy has been shown to result in an increased incidence of endometrial carcinoma in women. The present study was designed to investigate the effects of TAM (5 mg/kg and 7.5 mg/kg body wt) given i.g. to pregnant CD-1 mice (1x/day, days 12 through 18 of gestation) on their female offspring. Progressive proliferative hyperplasia of the oviduct was frequently seen in TAM-exposed offspring, reaching 100% incidence by 52 weeks in both treatment groups. These females also developed progressive proliferative uterine lesions, including moderate/severe cystic endometrial hyperplasia (34-50%) and polypoid adenomas (27-30%) between 53 and 78 weeks. Deciduomas (15%) occurred at young ages (12 and 24 weeks) while leiomyomas (14%), a malignant leiomyosarcoma, and ovarian granulosa cell tumors (14%), were found between 72 and 78 weeks. Our findings thus suggest a strong association between transplacental TAM and reproductive tract abnormalities in female CD-1 mice.   相似文献   
78.
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus.  相似文献   
79.
OBJECTIVE: Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation. STUDY DESIGN: We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals. RESULTS: In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age. CONCLUSIONS: Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants.  相似文献   
80.
OBJECTIVE: The ketogenic diet is a high-fat, low-protein, low-carbohydrate diet developed in the 1920s for the treatment of children with difficult to control seizures. Despite advances in both the pharmacotherapy and the surgery of epilepsy, many children continue to have difficult-to-control seizures. This prospective study sought to determine the ketogenic diet's effectiveness and tolerability in children refractory to today's medications. METHODS: One hundred fifty consecutive children, ages 1 to 16 years, virtually all of whom continued to have more than two seizures per week despite adequate therapy with at least two anticonvulsant medications, were prospectively enrolled in this study, treated with the ketogenic diet, and followed for a minimum of 1 year. Seizure frequency was tabulated from patients' daily seizure calendars and seizure reduction calculated as percentage of baseline frequency. Adverse events and reasons for diet discontinuation were recorded. RESULTS: The children (mean age, 5.3 years), averaged 410 seizures per month before the diet, despite an exposure to a mean of 6.2 antiepileptic medications. Three months after diet initiation, 83% of those starting remained on the diet and 34% had >90% decrease in seizures. At 6 months, 71% still remained on the diet and 32% had a >90% decrease in seizures. At 1 year, 55% remained on the diet and 27% had a >90% decrease in seizure frequency. Most of those discontinuing the diet did so because it was either insufficiently effective or too restrictive. Seven percent stopped because of intercurrent illness. CONCLUSIONS: The ketogenic diet should be considered as alternative therapy for children with difficult-to-control seizures. It is more effective than many of the new anticonvulsant medications and is well tolerated by children and families when it is effective.  相似文献   
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