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Large doses of antiprogestin typically disrupt menstrual cyclicity. A chronic low-dose regimen of the potent new antiprogestin ZK 137 316, which permits continued menstrual cyclicity but alters gonadal- reproductive tract activity, was established. Rhesus monkeys received vehicle (n = 6) or 0.01 (n = 8), 0.03 (n = 8) or 0.1 (n = 5) mg ZK 137 316/kg body weight daily for five menstrual cycles (C-1 to C-5). Oestradiol, progesterone and gonadotrophin profiles were normal during cycles involving vehicle and 0.01 and 0.03 mg ZK 137 316/kg body weight. In the 0.1 mg/kg group, mid-cycle oestradiol and gonadotrophin surges, and subsequent progesterone production, were absent in C-3 and C-5. Ovarian cyclicity was accompanied by timely menstruation in the vehicle and 0.01 mg/kg groups. By C-3, half the animals in the 0.03 mg/kg group and all animals in the 0.1 mg/kg group were amenorrhoeic. A corpus luteum was noted during the mid-luteal phase of C-5 in the vehicle, 0.01 mg/kg and 0.03 mg/kg groups. Large antral and cystic follicles were evident in the 0.1 mg/kg group. Thus, a daily treatment with 0.01 mg/kg ZK 136317 permitted normal menstrual cyclicity in macaques. While the daily administration of 0.03 mg/kg ZK 136 317 allowed ovarian cyclicity, menstruation was disrupted in some animals. Increasing the dose to 0.1 mg/kg antagonized pituitary function and resulted in anovulation and amenorrhoea. A chronic low-dose regimen of the antiprogestin ZK 137 316, which permits normal ovarian/menstrual cyclicity, has potential as a contraceptive in women.   相似文献   
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The aim was to investigate the effect of lanreotide (Angiopeptin) on urea synthesis. Lanreotide is a somatostatin analogue used in therapy trials of certain cancers. Cancer patients are often protein catabolic, thus the effect of lanreotide on whole body protein metabolism is of importance. We investigated the effect of lanreotide by measuring urea nitrogen synthesis rate (UNSR) and blood alpha-amino nitrogen levels before, during and after a 30 min iv infusion of 25 g of an electrolyte-free amino acid solution. 6 healthy male subjects were studied following, i) placebo (saline), ii) lanreotide 5 mug/kg, and iii) lanreotide 80 mug/kg. Lanreotide decreased urea nitrogen synthesis rate (mmol/h) during amino acid infusion significantly compared to saline, independent of dose of lanreotide (max +/- SE of urea nitrogen synthesis rate measurements in each study: 117 +/- 8 mmol/h (saline), 85 +/- 10 mmol/h (high dose) and 85 +/- 12 mmol/h (low dose)). This occurred in spite of significantly higher plasma alpha-amino nitrogen following lanreotide (peak +/- SE of alpha-amino nitrogen level in each study: 3.7 +/- 0.1 mmol/l placebo versus 4.8 +/- 0.2 mmol/l low dose and 4.7 +/- 0.4 mmol/l high dose (p < 0.01). We conclude that a single dose of lanreotide decreases whole body urea nitrogen synthesis rate thereby conserving body protein. The results indicate that long term lanreotide therapy may not lead to further protein catabolism in cancer patients.  相似文献   
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Biochemical evaluation of inflammation may be a useful adjunct to measures of pulmonary function and symptoms in children with asthma. However, little data have been provided to validate the markers in children. The aim of the present study was to assess circadian variations in serum eosinophil cationic protein (ECP), and serum and urine eosinophil protein X (EPX) in children. Five girls and two boys aged 10–14 years were studied. The first sample of urine consisted of urine collected from 24.00 hours the night before until 08.00 hours on the morning of the day of investigation. Thereafter urine was collected at 4-h intervals until 24.00 hours and in another 8-h interval from 24.00 to 08.00 hours. Blood samples for assessment of serum ECP and serum EPX were collected every 2 h during the 24 h. Statistically significant circadian variations in serum ECP (F=3.2, p=0.002), serum EPX (F=3.1, p=0.002) and in urine EPX/creatinine (F=5.4, p=0.003) were detected. The concentrations were higher during the night compared to daytime. Peak levels of serum ECP (mean [± SEM]) were found at 06.00 hours (16.3 [5.3] µg/l), trough levels at 08.00 hours (3.9 [0.7] µg/l) (p=0.01). Peak levels of serum EPX were seen at 06.00 (43.7 [9.5] µg/l) with trough levels at 12.00 hours (22.0 [3.5] µg/l) (p=0.01). Peak levels of urine EPX/creatinine occurred in urine collected from 24.00 to 08.00 hours (90.0 [27.7] µg/mmol), trough levels in the 16.00–20.00 hours sample (29.7 [8.9] µg/mmol) (p=0.02). Serum ECP, serum EPX and urine EPX exhibit a circadian variation in children with nocturnal and early morning peak levels. To avoid confounding influence from circadian variations in ECP and EPX in clinical studies blood or urine should be sampled at consistent times.  相似文献   
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Systemic vasodilatation in surfactant-depleted newborn piglets is induced by 200 mg/kg of modified porcine lung surfactant (Curosurf™). The aim of this investigation was to study whether this effect is dependent on dose and could further be induced by instillation of a bovine surfactant preparation (Survanta™). Twenty-two 3–5-d old piglets were subjected to repeated saline lung lavage and then randomized to one of three groups. Instillation of either Curosurf 100 mg/kg ( n = 8), Survanta 100 mg/kg ( n = 7) or Curosurf 200 mg/kg ( n = 7) was performed through the endotracheal tube. Systemic vascular resistance decreased 7 (± 4)%, 15 (± 12)% and 18 (± 6)% in the three groups, respectively ( p < 0:05 in all three groups). A significant difference between the high and low dose Curosurf groups was found ( p < 0:05), whereas no significant difference was seen between the Curosurf 100 mg group and the Survanta group. The decrease in vascular resistance was compensated by an increase in cardiac output, resulting in a stable mean arterial blood pressure. In conclusion, both Curosurf and Survanta induce a significant decrease in systemic vascular resistance in surfactant-depleted newborn piglets. A more pronounced effect was observed after 200 mg/kg than after 100 mg/kg of Curosurf.  相似文献   
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Krithika Rajagopalan  PhD    Linda Abetz  MA    Polyxane Mertzanis  MPH    Derek Espindle  MA    Carolyn Begley  OD  MS    Robin Chalmers  OD    Barbara Caffery  OD  MS    Christopher Snyder  OD  MS    J. Daniel Nelson  MD    Trefford Simpson  PhD    Timothy Edrington  OD  MS 《Value in health》2005,8(2):168-174
OBJECTIVE: The purpose of this study was to compare the discriminative properties of two generic health-related quality of life (QoL) instruments (SF-36 and EQ-5D) and a newly developed disease-specific patient-reported outcomes instrument (Impact of Dry Eye on Everyday Life (IDEEL)) to distinguish between different levels of dry eye severity. METHODS: Assessment of 210 people: 130 with non-Sjogren's Keratoconjunctivitis Sicca (non-SS KCS), 32 with Sj?gren's Syndrome (SS) and 48 controls; comparison of SF-36, EQ-5D, and IDEEL age-adjusted data by dry eye severity levels. Severity was assessed based on diagnosis (non-SS KCS, SS, control), patient-report (none, very mild, mild, moderate, severe, extremely severe) and clinician-report (none, mild, moderate, severe). RESULTS: Discriminative validity results were consistent for all instruments. Significant differences between severity levels were found with most SF-36 scales (P < 0.05), all EQ-5D scales (P < 0.05), and all IDEEL scales (P < 0.0001), except for Treatment Satisfaction. IDEEL scales consistently outperformed the generic QoL measures regardless of the severity criterion used. Most SF-36 scales outperformed the EQ-5D QoL scale, but the EQ-5D visual analog scale outperformed the SF-36 scales, except for General Health Perceptions. CONCLUSIONS: The disease-specific IDEEL scales are better able to discriminate between severity levels than the majority of the generic QoL scales. Preliminary evidence demonstrates that the IDEEL will be sensitive to QoL changes over time, although further testing in controlled longitudinal studies is needed.  相似文献   
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Central nervous system (CNS) toxicity is common at diagnosis and during treatment of pediatric acute lymphoblastic leukemia (ALL). We studied CNS toxicity in 1,464 children aged 1.0–17.9 years, diagnosed with ALL and treated according to the Nordic Society of Pediatric Hematology and Oncology ALL2008 protocol. Genome-wide association studies, and a candidate single-nucleotide polymorphism (SNP; n=19) study were performed in 1,166 patients. Findings were validated in an independent Australian cohort of children with ALL (n=797) in whom two phenotypes were evaluated: diverse CNS toxicities (n=103) and methotrexate-related CNS toxicity (n=48). In total, 135/1,464 (9.2%) patients experienced CNS toxicity for a cumulative incidence of 8.7% (95% confidence interval: 7.31–10.20) at 12 months from diagnosis. Patients aged ≥10 years had a higher risk of CNS toxicity than had younger patients (16.3% vs. 7.4%; P<0.001). The most common CNS toxicities were posterior reversible encephalopathy syndrome (n=52, 43 with seizures), sinus venous thrombosis (n=28, 9 with seizures), and isolated seizures (n=16). The most significant SNP identified by the genome-wide association studies did not reach genomic significance (lowest P-value: 1.11x10-6), but several were annotated in genes regulating neuronal functions. In candidate SNP analysis, ATXN1 rs68082256, related to epilepsy, was associated with seizures in patients <10 years (P=0.01). ATXN1 rs68082256 was validated in the Australian cohort with diverse CNS toxicities (P=0.04). The role of ATXN1 as well as the novel SNP in neurotoxicity in pediatric ALL should be further explored.  相似文献   
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Clinical research continues to provide an increasing number of studies that reveal an association between macular pigment optical density (MPOD) and both visual function and ocular health. As a result, there is a growing need for repeatable, accurate measures of MPOD that can describe peak optical density as well as spatial distribution. Measurement of MPOD in a research setting has an established history encompassing a number of both objective and subjective techniques. Transition of these techniques to a clinical setting has produced an array of commercial devices using three primary methods: heterochromatic flicker photometry, fundus autofluorescence and fundus reflectometry. The inherent differences among the techniques create difficulty in making direct comparisons between MPOD measurement devices. Understanding the limitations of each technique is critical in the clinical interpretation of MPOD results. Here, both the objective and subjective methods of MPOD measurement are reviewed with emphasis on the commercially available devices used in clinical settings.  相似文献   
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