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981.
Shark-liver oil (SLO) contains two bioactive lipids: alkylglycerols and n-3 PUFA. Alkylglycerols have immunostimulating and haematopoietic properties, while n-3 PUFA are essential for optimal neonatal development. We investigated the beneficial effects of dietary supplementation with 32 g SLO/d to twelve pregnant and then lactating sows (from day 80 of pregnancy to weaning) on the growth and immune status of their offspring, compared with a control group. Sows were vaccinated against Aujeszky's disease 21 d before term. Blood samples were collected from sows before treatment, on delivery and 14 d later, and from five piglets per litter on days 2, 21 and 36 after birth; colostrum and milk samples were collected 12 h, 14 and 28 d postpartum. Compared with controls, supplemented sows had higher levels of both erythrocytes and Hb in their blood, and higher concentrations of IgG, alkylglycerols and n-3 PUFA in their mammary secretions. In piglets from supplemented sows, leucocytes and IgG were higher. Supplementation with SLO resulted in an increase in Aujeszky antibodies in both blood and colostrum of sows after vaccination, together with an increase in Aujeszky antibodies in piglet blood. Our findings demonstrate that improvement of both passive and active immune status in piglets is related to the consumption of alkylglycerols associated with n-3 PUFA in the sow diet. The overall improvement in offspring health status by SLO supplementation to the mother could be of interest for optimisation of the lipid diet during and after pregnancy.  相似文献   
982.
Brain lesions induced in newborn mice or rats by the glutamatergic agonists ibotenate (acting on NMDA and metabotropic receptors) or S-bromowillardiine (acting on AMPA-kainate receptors) mimic some aspects of white matter cysts and transcortical necrosis observed in human perinatal brain damage associated with cerebral palsy. Exogenous and endogenous cannabinoids have received increasing attention as potential neuroprotective agents in a number of neurodegenerative disorders of the adult. One recent study showed neuroprotection by the cannabinoid agonist WIN-55212 in a newborn rat model of acute severe asphyxia. The present study was designed to assess the neuroprotective effects of the endogenous cannabinoid anandamide using a well-defined rodent model of neonatal excitotoxic brain lesions. In this model, anandamide provided dose-dependent and long-lasting protection of developing white matter and cortical plate reducing the size of lesions induced by S-bromowillardiine. Anandamide had only marginal neuroprotective effect against ibotenate-induced cortical grey matter lesions. Anandamide-induced neuroprotection against AMPA-kainate receptor-mediated brain lesions were blocked by a CB1 antagonist but not by a CB2 antagonist. Furthermore, anandamide effects were mimicked by a CB1 agonist but not by a CB2 agonist. Real-time PCR confirmed the expression of CB1 receptors, but not CB2 receptors, in the untreated newborn neocortex. Finally, neuroprotective effects of anandamide in white matter involved increased survival of preoligodendrocytes and better preservation of myelination. The present study provides experimental support for the role of endocannabinoids as a candidate therapy for excitotoxic perinatal brain lesions.  相似文献   
983.
1.--In this study, we aimed to characterize in vitro the effects of the benzofuran 5-HT(4) receptor agonists prucalopride, R149402 and R199715 and the indolic agents tegaserod and 5-HT in the atria of young pigs (10-11 weeks) and newborn piglets. 2.--In the paced left atrium of young pigs, only 5-HT results in positive inotropic responses when administered cumulatively (maximal effect relative to isoprenaline=53%, pEC(50)=6.8); however, all agonists showed lusitropic effects. Noncumulative administration results in greater positive inotropic responses for 5-HT and induces moderate positive inotropic responses for the other agonists; these responses fade. 3.--Phosphodiesterase (PDE) enzyme inhibition with 3-isobutyl-1-methylxanthine (IBMX; 20 microM) enhances the responses to cumulatively administered 5-HT (maximal effect=89%, pEC(50)=7.7) and reveals clear positive inotropic effects for prucalopride, tegaserod, R149402 and R199715; fading is abolished. The maximal effect of the benzofurans is less pronounced than that of the indoles. 4.--In the spontaneously beating right atrium of young pigs, all agonists show chronotropic activity when administered cumulatively in the absence of IBMX, without fade. Benzofurans behaved as partial agonists compared to 5-HT (maximal effect=54%, pEC(50)=6.5). 5.--In newborns, the inotropic activity of the agonists in the IBMX-treated left atrium was less pronounced than in the young pig; the same applied for the chronotropic response in the right atrium, except for 5-HT. 6.--In conclusion, the atrial responses to 5-HT(4) receptor activation increase in the first months of life; the inotropic response is regulated by PDEs. Prucalopride, R149402 and R199715 are partial agonists compared to 5-HT.  相似文献   
984.
A high performance liquid chromatography (HPLC) procedure for the determination of Delta9 tetrahydrocannabinol (THC) in human plasma is described. A two-step solid-phase extraction on CN cartridges was coupled with a reversed phase HPLC system. THC was eluted using a mobile phase composed of methanol, acetonitrile and tetrabutylammonium perchlorate solution (0.005 M, pH 3.2), through a C18 Nucleosil column and detected at a wavelength of 215 nm. Calibration curve was linear over the range 5-100 ng/ml with a lower limit of quantification validated at 5 ng/ml. Extraction recovery using the developed extraction procedure was higher than 85%. This method is presently used for the quantification of THC in plasma samples from regular cannabis smokers.  相似文献   
985.
986.

Purpose

To compare partial nephrectomy (PN) and percutaneous ablative therapy (AT) for renal tumor in imperative indication of nephron-sparing technique (NST).

Materials and methods

Between 2000 and 2015, 284 consecutive patients with a kidney tumor in an imperative indication of NST were retrospectively included in a multicenter study. PN [open (n = 146), laparoscopic (n = 9), or robotic approach (n = 17)] and AT [radiofrequency ablation (n = 104) or cryoablation (n = 8)] were performed for solitary kidney (n = 146), bilateral tumor (n = 78), or chronic kidney disease (CKD) (n = 60).

Results

Patients in the PN group had larger tumors and a higher RENAL score. There were no differences between the two groups with respect to age, reasons for imperative indication, and preoperative eGFR. Patients in the AT group had a higher ASA and CCI. PN had worse outcomes than AT in terms of transfusion rate, length of stay, and complication rate. Local radiological recurrence-free survival was better for PN, but metastatic recurrence was similar. Percentage of eGFR decrease was similar in the two groups. Temporary or permanent dialysis was not significantly different. On multivariate analysis, PN and AT had a similar eGFR change when adjusted for tumor complexity, reason of imperative indication and CCI.

Conclusion

In imperative indication of nephron-sparing treatment for a kidney tumor, either PN or AT can be proposed. PN offers the ability to manage larger and more complex tumors while providing a better local control and a similar renal function loss.
  相似文献   
987.
We describe a woman with profound mental retardation and a direct duplication of 16q and fragile site fra(10)(q25). The identification and possible origin of the duplicated 16q is discussed along with the clinical manifestations. To our knowledge this is the first direct duplication of 16q to be reported. The karyotype is shown to be 46,XX, dir dup (16) (q11.2----q13).  相似文献   
988.
A genome-wide survey of human pseudogenes   总被引:8,自引:0,他引:8       下载免费PDF全文
Torrents D  Suyama M  Zdobnov E  Bork P 《Genome research》2003,13(12):2559-2567
We screened all intergenic regions in the human genome to identify pseudogenes with a combination of homology searches and a functionality test using the ratio of silent to replacement nucleotide substitutions (KA/KS). We identified 19,724 regions of which 95% ± 3% are estimated to evolve neutrally and thus are likely to encode pseudogenes. Half of these have no detectable truncation in their pseudocoding regions and therefore are not identifiable by methods that require the presence of truncations to prove nonfunctionality. A comparative analysis with the mouse genome showed that 70% of these pseudogenes have a retrotranspositional origin (processed), and the rest arose by segmental duplication (nonprocessed). Although the spread of both types of pseudogenes correlates with chromosome size, nonprocessed pseudogenes appear to be enriched in regions with high gene density. It is likely that the human pseudogenes identified here represent only a small fraction of the total, which probably exceeds the number of genes.  相似文献   
989.
Sprague Dawley rats were immunized with graded doses of ovalbumin (O A) together with alum. The capacity of the animals to produce a bronchial anaphylactic response to intravenous antigen challenge was related to serum OA-IgE and OA-IgG2a antibody levels estimated by radioimmunossay. A significant correlation between bronchial anaphylactic response capacity and OA-IgE antibody levels was found under a few, but not all, of several carefully chosen experimental conditions. No correlation was demonstrable between the in vivo reactivity of the animals and their serum levels of OA-specific IgGg2a antibodies.  相似文献   
990.
BACKGROUND: Assisted reproduction technologies can treat infertility for human immunodeficiency virus (HIV) seropositive women. We assessed the efficacy of these techniques in the results and difficulties encountered while conducting our assisted reproduction programme for 49 couples in which at least the woman had HIV infection that was currently under control. METHODS: Treatments included intrauterine insemination (IUI), IVF and ICSI, with ovarian stimulation. Embryos were transferred on day 3 after oocyte retrieval. An elective single transfer was performed, except for patients aged > or = 40 years. RESULTS: The median age of the women was 36 years. Ten IUI, nine IVF, 53 ICSI and 10 frozen-thawed embryo transfers have been performed. No pregnancy occurred following the IUI trials but for the couples with IVF and ICSI attempts the clinical pregnancy rate per embryo transfer was 23.9%. Eight babies have been born leading to a 22.2% take home baby rate per treated couple. Contamination was not observed in any newborn. CONCLUSIONS: Assisted reproduction technologies and particularly ICSI can provide HIV seropositive women with a safe means of mothering children. Results are encouraging when considering the age of the patients and a preferential single embryo transfer.  相似文献   
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