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1.
Iron deficiency may exacerbate symptoms in the Restless Legs Syndrome (RLS). We investigated the effect of intravenous iron sucrose or placebo on symptoms in patients with RLS and mild to moderate iron deficit. Sixty patients with primary RLS (seven males, age 46 (9) years, S‐ferritin ≤45 μg/L) recruited from a cohort of 231 patients were randomly assigned in a 12‐months double‐blind, multi‐centre study of iron sucrose 1000 mg (n = 29) or saline (n = 31). The primary efficacy variable was the RLS severity scale (IRLS) score at week 11. Median IRLS score decreased from 24 to 7 (week 11) after iron sucrose and from 26 to 17 after placebo (P = 0.123, N.S. for between treatment comparison). The corresponding scores at week 7 were 12 and 20 in the two groups (P = 0.017). Drop out rate because of lack of efficacy at 12 months was 19/31 after placebo and 5/29 patients after iron sucrose (Kaplan–Meier estimate, log rank test P = 0.0006) suggesting an iron induced superior long term RLS symptom control. Iron sucrose was well tolerated. This study showed a lack of superiority of iron sucrose at 11 weeks but found evidence that iron sucrose reduced RLS symptoms both in the acute phase (7 weeks) and during long‐term follow up in patients with variable degree of iron deficiency. Further studies on target patient groups, dosing and dosing intervals are warranted before iron sucrose could be considered for treatment of iron deficient patients with RLS. © 2009 Movement Disorder Society  相似文献   
2.

Objectives

For individuals not on antiretroviral therapy, the risk of heterosexual transmission of HIV appears negligible when blood plasma (BP) viral loads are <1500 HIV‐1 RNA copies/mL. It is not clear whether this observation can be extrapolated to individuals on highly active antiretroviral therapy (HAART). Because of differential tissue penetration, antiretroviral drug concentrations may be sufficient to maintain an undetectable viral load in the BP yet not achieve adequate levels to suppress HIV in the genital tract. Therefore, we wanted to correlate HIV viral loads and drug concentrations in semen plasma (SP) and BP.

Methods

Thirty‐three men were included. All were on combination antiretroviral therapy with an undetectable BP viral load for at least 1 year. Blood and semen samples were collected within 2 h of each other and tested for HIV RNA by the NucliSens QT (bioMerieux, St Laurent, QC, Canada) method; drug concentrations were determined by liquid chromatography tandem mass spectrometry.

Results

Two of the 33 patients (6.1%) with BP viral loads below detection had time‐matched HIV viral loads in SP ≥700 copies/mL. Both patients were on efavirenz, the SP concentrations of which were ≤10% of the levels in BP and well below the minimal therapeutic drug monitoring target concentration required to suppress HIV.

Conclusions

Because, at least in part, of poor drug penetration into the genital tract, an undetectable HIV viral load in the BP does not guarantee an undetectable viral load in semen. In view of this, caution should be taken in concluding that patients on HAART with suppressed viraemia are sexually non‐infectious.  相似文献   
3.
4.
In a prospective, controlled, randomized study where two differentagonists were used, we compared three different long desensitizationprotocols for induction of multiple follicular growth in medicallyassisted conception cycles. In protocol A, 30 patients wereinjected with buserelin twice a day for 15 days prior to ovarianstimulation until human chorionic gonadotrophin (HCG) administration.In protocol B, 30 patients were injected with a single doseof long acting Triptorelin (3.75mg) 15 days before the ovarianstimulation onset. In protocol C, 30 patients were injectedwith the long acting Triptorelin 4 weeks before ovarian stimulationfollowed by daily administration of 0.1 mg of the same agonistuntil HCG injection. There was no difference in the ovarianresponse to exogenous gonadotrophin stimulation, except forthe presence of premature luteinization in two patients in groupB. A significantly higher number of mature oocytes was collectedfrom patients with protocol A; however, the fertilization andcleavage rate demonstrated no significant difference among thethree groups of patients. The ongoing pregnancy rate and theimplanation rate per treatment cycle were very similar in thethree study groups. When the convenience, cost and side-effectsfor the patient are being considered, protocol B should be selectedas the first choice when the agonist is utilized for the purposeof inducing pituitary desensitization before and during ovarianstimulation.  相似文献   
5.
利用光散射法对盛夏时节成都市区空气中的风尘浓度及分散度进行了测试,并就风尘的粒径分布及分散度的统计模式、气象参数时飘尘浓度的影响,以及飘尘浓度和分散度的日变化进行了分析。结果表明:成都市区空气中飘尘的大多数粒径分布的统计模式为Junge分布,峰值浓度出现在中午12:00前后,相对湿度对空气中飘尘浓度影响显著,降雨对风尘有明显的清除作用。测试结果对评价城市环境卫生条件和分析人类活动对环境的干扰情况有参考价值。  相似文献   
6.
降调节对卵子质量的影响   总被引:2,自引:0,他引:2  
近10余年来,在体外受精一胚胎移植(IVF-ET)周期中应用促性腺激素释放激素激动剂(GnRH-a)进行控制性卵巢刺激(COS)已成为普遍采用的方法,其主要原因是GnRH-a可以促进卵巢内多个卵泡同步发育和成熟,抑制内源性黄体生成素(LH)峰,阻遏卵泡过早黄素化及卵子早熟。由于GnRH-a在IVF-ET进行降调节COS中的应用不同,可将COS方案分为长方案和短方案。[第一段]  相似文献   
7.
A BASIC computer program is described which is useful for calculating filling concentrations for ALZET osmotic mini-pumps employed in studies of chronic drug and hormone administration. After the user has entered the required daily dose, the pump parameters and the animals' weights, the program gives the following information: The total quantity of the drug or hormone required for the experiment; the minimum volume and concentration of solution, allowing a 10% margin for error, to serve as a standard that, when diluted, will fill all pumps in the experiment; individual volumes of this solution that, when diluted to a constant volume will yield the required concentrations to fill each of the respective pumps. Use of this program will ensure reliably accurate and very rapid preparations of solutions for mini-pump use.  相似文献   
8.
Cytogenetic damage in operation theatre personnel   总被引:3,自引:0,他引:3  
The study in a group of 24 (11 anaesthetists and 13 support staff) was planned to ascertain the cytogenetic risk in a group of theatre personnel who worked in various city hospitals. Their exposure in terms of duration of service vary from 3-30 years. The control group (n = 24) consisted of people with different occupations matched for possible confounding variables. Cytogenetic risk was assessed in terms of chromosome aberration and sister chromatid exchange in 72-hour lymphocyte cultures. A significant increase in the percentage of chromosome aberration was observed. The sister chromatid exchange was double that of the baseline value in 20% of the exposed individuals. These findings indicate the possible risk of cytogenetic damage for staff working in unscavenged rooms.  相似文献   
9.
Special Pharmacokinetic Considerations in Children   总被引:4,自引:2,他引:2  
W. Edwin Dodson 《Epilepsia》1987,28(S1):S56-S69
Summary: Pediatric patients have greater degrees of pharmacokinetic variability and unpredictability than adults. This variability results from the effects of pharmacogenetics, age and growth, prior and current comedication, and disease. Newborns with seizures have the least predictable dosage requirements, and their needs change as drug-eliminating mechanisms mature in the neonatal period. Infants have the highest relative capacities to eliminate antiepileptics of any age group and require the largest relative doses. In addition to age-related trends, children demonstrate the same drug-specific, pharmacokinetic phenomena that adults do, including nonlinear phenytoin elimination, nonlinear valproate binding, and autoinduction of carbamazepine. Intercurrent illness and drug interactions further modify the age-related pharmacokinetic patterns in children and make dosage requirements even more unpredictable. Recent studies have shown that febrile illness can affect drug elimination, sometimes decreasing drug levels by 50% or more. Intermittent treatment with benzodiazepines administered either orally or rectally can be an important adjunct and help minimize this type of problem for children with marginally controlled epilepsy. Intermittent benzodiazepines are also helpful for children who have febrile seizures and who need only occasional antiepileptic protection.  相似文献   
10.
Summary These studies were designed to determine the role of the central nervous system, the sympathetic nervous system, the adrenal glands and the renal sympathetic nerves in yohimbine-induced renin release in conscious rats. Yohimbine (0.3–10 mg/kg, s.c.) caused time- and dose-related increases in plasma renin activity (PRA) and concentration (PRC) which were accompanied by time- and dose-related elevations of plasma norepinephrine (NE) and epinephrine (Epi) concentrations. Significant positive correlations were found between the increases in PRA and the increases in plasma NE and Epi concentrations caused by yohimbine, and propranolol (1.5 mg/kg, s.c.) blocked 90% of yohimbine (3 mg/kg, s.c.)-induced renin release. Over the entire spectrum of doses of yohimbine, the increases in PRA and plasma NE and Epi concentrations were positively correlated with the decreases in mean arterial pressure (MAP), but the -intercept was positive in every case and the 1 mg/ kg dose of yohimbine consistently increased PRA independent of any change in MAP. Complete renal denervation, as evidenced by a greater than 90% reduction in renal NE content, did not alter the increase in PRA caused by yohimbine (3 mg/kg, s.c.). An increase in circulating plasma catecholamine concentrations appeared to mediate yohimbine-induced renin release since propranolol prevented the rise in PRA caused by yohimbine in renal denervated rats. Prior adrenalectomy (Adx) also failed to prevent the rise in PRA produced by yohimbine (3 mg/kg, s.c.), but a combination of Adx and renal denervation caused a significant impairment of yohimbine-induced renin release. However, neither Adx alone nor the combination of Adx and renal denervation affected the increase in plasma NE concentration caused by yohimbine. Complete transection of the spinal cord at C8 caused a drastic reduction in plasma catecholamine concentrations but did not change basal PRC. Yohimbine (3 mg/kg, s.c.) did not increase PRC or plasma catecholamine concentrations after spinal transection. Based on these results, we conclude that 1) the stimulation of renin release by yohimbine is a secondary neurohormonal consequence of the generalized increase in sympathetic activity caused by yohimbine, 2) the sympathoadrenal activation produced by yohimbine results from an action in the brain which is amplified by the simultaneous blockade of prejunctional 2-adrenoceptors and 3) vasodepressor effects of the larger doses yohimbine cause a baroreflexly-mediated increase in sympathetic activity which interacts in a positive fashion with the central and peripheral sympathoexcitatory effects of yohimbine. Send offprint requests to T. K. Keeton  相似文献   
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