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991.
992.
Background

The overall prognosis and survival of patients with advanced gastric cancer are generally poor. Extended lymphadenectomy is recommended for patients with advanced gastric cancer; however, splenectomy and distal pancreatectomy performed with an extended lymph node dissection may be associated with increased morbidity and mortality.

Method

Electronic literature searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from 1 January 1998 to 31 December 2009. Studies on gastric carcinoma investigating extended lymphadenectomy with splenectomy and/or pancreaticosplenectomy that reported data on surgical outcomes or survival were selected.

Results

Forty studies were included in this review. Decreased complication rates were demonstrated with spleen preservation in two prospective studies and three retrospective studies, and with pancreas preservation in five retrospective studies. No randomized controlled trial showed survival benefit or detriment for preservation of spleen or pancreas in extended lymphadenectomy. Improved survival was demonstrated with spleen preservation in two prospective and eight retrospective studies, and with pancreas preservation in one prospective and four retrospective studies.

Conclusions

Preservation of the spleen and pancreas during extended lymphadenectomy for gastric cancer decreases complications with no clear evidence of improvement or detriment to overall survival.

  相似文献   
993.
Seevaratnam  Rajini  Bocicariu  Alina  Cardoso  Roberta  Mahar  Alyson  Kiss  Alex  Helyer  Lucy  Law  Calvin  Coburn  Natalie 《Gastric cancer》2011,15(1):60-69
Background

Surgery is the only curative treatment for patients with gastric cancer. However, the extent of lymph node dissection is still debated. Therefore, with the publication of newer trial results, we conducted an updated meta-analysis of D1 versus D2 randomized controlled trials comparing outcomes.

Methods

Systematic searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from January 1, 1985, to December 31, 2010. Meta-analyses were performed using RevMan v5 software. Both short- and long-term outcomes were analyzed. Subgroup analyses of T stage and spleen/pancreas resection versus preservation were performed.

Results

Outcomes of 5 randomized trials involving 1642 patients (845 D1, 797 D2) enrolled from 1982 to 2005 were included. Despite the addition of the more recent trials, overall hospital mortality and reoperation rates were still higher in D2 cases. Subgroup analysis of recent trials and spleen/pancreas preservation revealed no significant difference in hospital mortality between groups. Five-year overall survival was similar between D1 versus D2 trials. Sub-analysis by tumor depth and spleen/pancreas preservation detected trends for improved survival with D2 lymphadenectomy in T3/T4 patients and those with spleen/pancreas preservation.

Conclusion

Earlier trials show that D2 dissections have higher operative mortality, while recent trials have similar rates. A trend of improved survival exists among D2 patients who did not undergo resection of the spleen or pancreas, as well as for patients with T3/T4 cancers.

  相似文献   
994.
Outcomes of ACR after pediatric HTx have been well described, but less has been reported on outcomes of AMR. We compared the clinical characteristics and cardiovascular outcomes (composite end‐point of death, retransplantation, or allograft vasculopathy) of pediatric HTx recipients with AMR, ACR, and no rejection in a retrospective single‐center study of 104 recipients. Twenty were treated for AMR; 15 were treated for ACR. Recipients with AMR had an increased frequency of congenital heart disease (90% vs ACR 67% vs no rejection 59%, P = .03), homograft (68% vs 7% vs 18%, P < .001), HLA sensitization (45% vs 13% vs 13%, P = .008), and positive cross‐match (30% vs 7% vs 9%, P = .046). AMR caused hemodynamic compromise more often than ACR (39% vs 4%, P = .02). AMR recipients had worse cardiovascular outcome than recipients with ACR or no rejection (40% vs 20% vs 8.6%, P = .003). In bivariate Cox analysis, AMR (HR 4.1, CI 1.4‐12.0, P = .009) and ischemic time (HR 1.6, CI 1.1‐2.3, P = .02) were associated with worse cardiovascular outcome; ACR was not. In summary, pediatric HTx recipients who develop AMR have worse cardiovascular outcome than recipients who develop only ACR or experience no rejection at all.  相似文献   
995.
PH is a risk factor for GL after HTx. However, traditional parameters are not reliable predictors of risk in children. We hypothesized that DPI (dPAP and DPG) are predictive of GL in pediatric HTx recipients. The UNOS/SRTR database was reviewed to identify pediatric HTx recipients (age <18 years) between 1994 and 2013. Recipients with pretransplant hemodynamic data were grouped by diagnosis (CMP or CHD), and the groups were analyzed separately. Bivariate Cox regression analysis examined the association between hemodynamic variables and GL. DPI showed the strongest association with early GL in recipients with CMP (dPAP: HR = 1.25 [1.09‐1.42]; DPG: 1.24 [1.11‐1.38]). Among CHD recipients, DPI were associated with early GL in those with preexisting PH (dPAP: HR = 1.16 [1.01‐1.33]; DPG: HR = 1.10 [1.00‐1.21]). No cutoff values for “high‐risk” DPI were identified, but a continuous relationship between higher DPI and risk of early GL was observed. DPI are associated with early GL in select pediatric HTx recipients. Our findings suggest that DPI should be considered as part of routine hemodynamic assessment for pediatric HTx candidates.  相似文献   
996.
The effect of a neutral amino acid, 2-aminoisobutyric acid (AIB) on steady state cell volume has been examined in rat renal papillary slices incubated in hyperosmotic media (2,000 mosmol/kg H2O) containing high concentrations of NaCl and urea (thus imitating papillary interstitial fluid the intact kidney during antidiuresis). Volumes were significantly increased (P<0.001) when external AIB was raised from 0.1 to 10 mmol/l. Na+-dependent AIB uptake occurred, and there were net increases in cell contents of Na+ and Cl. Replacement of Na+ by Li+, but not by other cations did not influence the effect of AIB concentration on cell volume, but this was abolished when Cl was replaced by other anions. The effect of AIB was abolished by diphenylamine-2-carboxylate (10–3 mmol/l), bumetanide (at 1 mmol/l but not 10–2 mmol/l) and by N,N-dicyclohexylcarbodiimide (0.5 mmol/l), but not by amiloride (1 mmol/l) or 4-acetamido-4-iso-thiocyanato-stilbene-2,2-disulphonic acid (1 mmol/l), and was enhanced by the presence of Ba2+ or quinine (1 mmol/l). The findings are interpreted in terms of an inwardly-directed Na+-amino acid contransporter which determines steady-state volume, requires simultaneous entry of Cl through conductive pathways, and whose effects on cell volume are moderated by K+ efflux through volume-sensitive K+ channels.  相似文献   
997.
The human gene coding for lactate dehydrogenase C (LDHC), a testis-specific isozyme, has been assigned to a refined region of chromosome 11, p14.3–p15.5, in which the lactate dehydrogenase A gene LDHA also resides, by using somatic cell hybrids and in situ chromosome hybridization. This assignment clearly indicates the close physical proximity of the LDHC and LDHA genes and supports the evolutionary closeness of these two isozymes.  相似文献   
998.
Objective  We investigated the application of high-resolution microarray-based comparative genomic hybridisation (array CGH) on a fetus showing increased nuchal translucency (NT).
Design  Case study.
Setting  Tertiary referral obstetrics unit.
Sample  Pregnant woman attended the antenatal clinic.
Methods  Conventional karyotyping and genetic test was carried out for the alpha-globin gene. High-resolution array CGH using the high-density 244K Agilent microarray was performed on fetal blood sample by cordocentesis to investigate the possibility of any genomic imbalance.
Main outcome measures  Detection of chromosomal abnormality.
Results  Karyotyping analysis showed 46,XY. Molecular genetic diagnosis confirms the fetus has Hb-H constant spring disease but cannot explain the increased NT to 3.2 mm. Array CGH analysis discovered a 1.32-Mb microdeletion on chromosome 16p13.11. Deletion at 16p13.11 has been implicated to predispose to autism and/or mental retardation. Baby was delivered at 40 weeks of gestation, and follow up was carried out at 3 months of age without sign of mental retardation/developmental delay.
Conclusions  This case study demonstrated that array CGH can accurately calibrate the size and identify de novo interstitial chromosome imbalances. However, the presence of chromosome copy variants with unknown clinical significance currently limits its wider scale application in prenatal diagnosis and needs further investigations.  相似文献   
999.
Summary A "picture book" of surface potentials, Laplacians, and magnetic fields due to distributed, neocortical sources is presented. The mathematically simulated data is based on 4200 current sources at the macrocolumn scale. Estimated scalp surface maps are based on the three-concentic spheres model of the head. Emphasis is placed on the effects of sampling with a limited number of electrodes, the choice of reference electrode, and the use of the spline Laplacian to improve spatial resolution. The spline Laplacian is applied to median and ulnar nerve somatosensory evoked potentials and to auditory evoked potentials including P300. Substantial improvement in spatial resolution over conventional methods is obtained. The implementation of practical high resolution EEG systems based on the spline Laplacian is considered.The authors greatfully acknowledge the technical assistance of Chris Fritton, Laurie Orth, and Chiraprakash Nayak. This research was supported by NIH grant RO1 NS24314.Invited paper, Submitted to Brain Topography, July, 1991  相似文献   
1000.
Pediatric valganciclovir dosing recommendations have not been extensively validated for prevention or treatment for CMV infection. As such, we performed a pharmacokinetic study to compare different valganciclovir dosing regimens and the potential benefits of individualized dose adjustments in children following organ transplantation. Ganciclovir AUCs were calculated from four plasma drug levels in pediatric SOT recipients aged six months through three yr receiving valganciclovir suspension by mouth. Of the 28 ganciclovir AUC calculations performed, 11 (39%) were outside the therapeutic target range of 40–60 mcg h/L leading to a valganciclovir dose adjustment. Current manufacturer‐recommended dosing based on BSA and CrCl was estimated to result in therapeutic AUCs in fewer patients than the simple weight‐based formula used in our institution (4 vs. 13; p = 0.017). An AUC calculation using only the two‐ and five‐h measurements was strongly correlated with the AUC using all four time measurements (R2 = 0.846; p < 0.001). A simple weight‐based dosing approach gives a higher probability for therapeutic AUCs compared to the manufacturer‐recommended dosing in pediatric transplant patients aged six months through three yr with normal renal function. An AUC calculated using two sample times might allow for fewer blood draws in the future.  相似文献   
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