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91.
The aim of the present study was to examine the reproductive effects of two perorally applied phytoestrogens, genistein (8 mg/kg/day) and beta-sitosterol (50 mg/kg/day), on the mink (Mustela vison) at human dietary exposure levels. Parental generations were exposed over 9 months to these phytoestrogens and their offspring were exposed via gestation and lactation. Parents and their offspring were sampled 21 days after the birth of the kits. Sex hormone levels, sperm quality, organ weights, and development of the kits were examined. The exposed females were heavier than the control females at the 1st postnatal day (PND). The control kits were heavier than the exposed kits from the 1st to the 21st PND. Phytoestrogens did not affect the organ weights of the adult minks, but the relative testicular weight of the exposed kits was higher than in the control kits. The relative prostate weight was higher and the relative uterine weight lower in the beta-sitosterol-exposed kits than in the control kits. Moreover, the plasma dihydrotestosterone levels were lower in the genistein-exposed male kits compared to the control male kits. This study could not explain the mechanisms behind these alterations. The results indicate that perinatal phytoestrogen exposures cause alterations in the weight of the reproductive organs of the mink kits.  相似文献   
92.
BACKGROUND: Because the results of short-term recombinant human growth hormone (rhGH) treatment in children with growth impairment after liver transplantation (LTx) have been promising, we have studied the long-term effects of rhGH on growth and graft function after LTx. METHODS: Indications for rhGH treatment were height standard deviation score (hSDS) below -2.0 or growth velocity SDS below 0 and LTx at least 18 months before inclusion. Eight growth-retarded children were treated with rhGH for more than 5 years. RESULTS: During the first year, median growth rate improved from 3.3 to 7.0 cm/year. In the second and third year, growth velocity remained high at 6.6 cm/year and 6.2 cm/year, respectively (P=0.008). In the fourth year, median growth velocity started to decline but still remained above baseline during the fifth year of treatment (4.2 cm/year). The median hSDS improved from -3.6 to -2.7. During the rhGH treatment, no acute rejection episodes were detected, and graft function remained stable in all except one patient. She was diagnosed with chronic rejection in the third year of rhGH treatment. The patient had elevated liver enzymes and abnormal liver function tests already before rhGH treatment. CONCLUSIONS: The efficacy of rhGH treatment is sustained after the first year in liver-transplant children with non-GH-deficient growth retardation. Because of a potential risk of side effects, close monitoring of these patients is required.  相似文献   
93.
BACKGROUND: Ischemia-reperfusion injury secondary to leukocyte activation has been widely recognized as one of the most relevant mechanism leading to postoperative organ dysfunction occurring after a period of ischemia. The aim of the present study was to evaluate in a prospective, randomized study, the value of leukocyte depleting filter in patients undergoing elective coronary artery bypass surgery. METHODS: Twenty patients scheduled for elective on-pump coronary artery bypass surgery were randomized to undergo cardiopulmonary bypass either with a leukocyte depleting filter incorporated in the extracorporeal circulation arterial line or without a filter. RESULTS: The main finding of this study was the significantly lower postoperative concentrations of cardiac troponin I in the leukocyte filter group (Tests of between-subjects effects: p = 0.024). There were also slightly better cardiac indices in the leukocyte filter group. A larger amount of blood units was infused intra- and postoperatively in patients undergoing cardiopulmonary bypass with leukocyte filtration (median, 600 [IQR, 0-1200] vs. 0 [IQR, 0-600], p = 0.08). Two patients in the leukocyte filter group underwent reoperation for bleeding but none in the control group (p = 0.48). Intra-and postoperative platelet count was lower in the leukocyte filter group (Tests of between-subjects effects: p = 0.08). Despite a significant increased concentration of C-reactive protein on the first postoperative day in the control group (p = 0.029), repeated-measures analysis failed to show any significant increase during the study period (p = 0.33). CONCLUSIONS: The results of this study suggest a myocardial protective effect of leukocyte filter in the setting of elective coronary artery bypass surgery.  相似文献   
94.
Desorption kinetics were determined for fluoranthene (FLU) and trifluralin (TF) spiked onto Lake Erie and Lake Huron, USA, sediments at three concentrations (10, 40, 100 mg/kg dry wt). Following four months of equilibration, desorption was measured by extraction with Tenax and the data were fit to a first-order three-compartment kinetic model. The rate constants of the rapidly (k(rap)), slowly (k(slow)), and very slowly (k(vs)) desorbing fractions were on the order of 10(-1)/h, 10(-2-3)/h, and 10(-4)/h, respectively. The t99.9 (time required for 99.9% of the FLU and TF to desorb from each pool value) for each compartment indicated that FLU and TF desorption from rapid, slow, and very slow compartments were on the order of hours, days, and years, respectively. Higher rates of desorption were observed for FLU and TF from the Lake Huron sediments and this was not apparently related to the total organic carbon (TOC), particle size distribution, or polarity (carbon-to-nitrogen ratio) of the sediments. In general, the total fraction of the initial contaminant amounts that desorbed over the time course was directly related to concentration, which we hypothesized was due to the combined effects of saturation of high-energy (slow and very slow) binding sites in the organic carbon matrix and hysteresis. In extrapolations to field conditions, FLU and TF were predicted to persist in the sediments for years due to the very slow desorption of an estimated 31 to 53% of the bulk concentrations. Based on the rapidly desorbing fractions, the bioavailable amounts of the contaminants were predicted to be between 31 to 55% of bulk sediment concentrations.  相似文献   
95.
In bioavailability studies, the biota sediment accumulation factor (BSAF) is invoked to describe the thermodynamic partitioning of a hydrophobic organic contaminant (HOC) between the organism lipid and the organic carbon fraction of the sedimentary matrix and accounts for differences in bioavailability among sediments. Bioaccumulation experiments were performed with Lumbriculus variegatus and Diporeia species exposed in seven sediments dosed with 2,4,5,2',4',5'-hexachlorobiphenyl (HCBP) and benzo[a]pyrene (BaP) or pyrene (PY) and 3,4,3',4'-tetrachlorobiphenyl (TCBP). The BSAF values for the nonplanar HCBP were consistent with equilibrium partitioning theory (EQP) and averaged 2.87 for L. variegatus and 1.45 for Diporeia, while the BSAF values for the planar compounds (BaP, PY, TCBP) were generally lower than estimated from EQP (<1). Correcting the BSAF values of the planar compounds for enhanced sorption due to black carbon improved the BSAF values for L. variegatus, generally resulting in values consistent with EQP, but substantial variation remained for Diporeia. The BSAF values for the planar compounds showed significant positive correlations with plant-derived carbon in sediments (lignin and pigments) but were more consistent for L. variegatus than for Diporeia. These correlations imply that compounds sorbed to plant-derived carbon are more bioavailable since this material is more likely ingested providing a second exposure route.  相似文献   
96.
Sia AT  Goy RW  Lim Y  Ocampo CE 《Anesthesiology》2005,102(3):651-656
BACKGROUND: The study was designed to determine and compare the median effective doses (MEDs) of intrathecal ropivacaine with levobupivacaine for labor analgesia. METHODS: In this double-blind study, 100 parturients in early labor were randomized to receive either intrathecal ropivacaine or levobupivacaine. For each drug, the patients were assigned to receive one of the five doses studied, namely 1, 1.5, 2, 2.5, or 3 mg. Effective analgesia was defined as a pain score (0-100 visual analog scale) of less than 10 within 15 min of injection, lasting for 45 min or more after the induction of analgesia. MEDs were derived from probit analysis. The duration of analgesia rendered by the two drugs at 2.5 and 3 mg was also compared. RESULTS: The MED for levobupivacaine was 1.07 mg (95% confidence interval, 0.88-1.25 mg), and the MED for ropivacaine was 1.40 mg (95% confidence interval, 1.20-1.61 mg). Levobupivacaine was found to be 1.31 (95% confidence interval, 1.04-2.01) times more potent than ropivacaine. At doses of 2.5 mg or greater, there was no significant difference in duration of analgesia between levobupivacaine (median, 63.5 min; range, 46-123 min) and ropivacaine (median, 59.0 min; range, 47-93 min; P = 0.18). We detected no difference in the incidence of hypotension, nausea and vomiting, motor block, or abnormal fetal heart tracing between the two drugs. CONCLUSIONS: The MED of intrathecal ropivacaine for labor analgesia was significantly greater than levobupivacaine experimentally, but this significance was reduced when the comparison was based on molar potency. There was no difference in the duration of analgesia or adverse effects between the two drugs at higher doses (2.5 mg or greater).  相似文献   
97.
OBJECTIVE: Childhood adversities have been associated with adulthood depressiveness, but the contribution of adult risk factors is seldom described. We examined whether adult risk factors lie on the pathway from childhood adversity to adult depressiveness (pathway hypothesis) or whether the association depends on life events (vulnerability hypothesis). METHOD: Among 21,101 randomly sampled working-aged respondents [the Health and Social Support in Finland (HeSSup) Study], the hypotheses were tested with logistic regression analysis models studying the associations between Beck Depression Inventory (BDI)-assessed depressiveness and self-reported childhood adversities alone and in combination with recent adverse events. RESULTS: Childhood adversities were consistently associated with depressiveness (women, age-adjusted odds ratio 3.1, 95% confidence intervals 2.6-3.7; men, 2.6, 2.1-3.3), although the risks were decreased by more than 30% after adjustments for adult risk factors such as living alone, education, alcohol consumption, social support and negative affectivity. Childhood adversities combined with recent life events were associated with depressiveness in an additive manner. Women with childhood adversities and recent person-independent events especially had increased vulnerability for depressiveness. CONCLUSIONS: The childhood adversity-depressiveness associations were partly mediated by adult risk factors, supporting a pathway from childhood adversities to depressiveness through adult risk factors. Increased vulnerability for depressiveness was found among respondents with childhood adversities in combination with recent death/illness events. The findings emphasize the importance of early risk factors when identifying persons at risk of depression.  相似文献   
98.
99.
Aim: To examine the influence of recurrent therapy with antibiotics (RTA) in infancy on children's somatic factors at 8 y of age. Methods: Subject selection was based on stratified randomized cluster sampling. Altogether 1287 infants were potential participants in the follow-up study. Children with ≥6 courses of antibiotics (100 children) during their first 18 mo of life and children with no (62%) or ≤2 courses (38%) of antibiotics participated in a clinical examination in a case-control setting (100 matched controls) at the age of 8 y. Results: The children with RTA continued to have more infections and had had more courses of antibiotics compared to controls during the follow-up. There was no clinically significant difference in the somatic and dental status at the age of 8 between the two groups. The parents of the children with RTA reported significantly more often recurrent infections than the parents of the controls.

Conclusions: The children with recurrent therapy with antibiotics in early childhood also continue to be prescribed more antibiotics in later childhood when compared to those who received no or few antibiotics in infancy. However, recurrent infections and medications do not seem to have a marked effect on the somatic and dental status of these children at 8 y of age.  相似文献   
100.
Success in the treatment of infected orthopedic prosthesis requires the best surgical approach in combination with prolonged optimum targeted antimicrobial therapy. In choosing the surgical option, one must consider the type of infection, condition of the bone stock and soft tissue, the virulence and antimicrobial susceptibility of the pathogen, the general health and projected longevity of the patient, and the experience of the surgeon. If surgery is not possible, an alternative is long-term oral antimicrobial suppression to maintain a functioning prosthesis. Treatment must be individualized for a specific infection in a specific patient.  相似文献   
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