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71.
Wernovsky G Kuijpers M Van Rossem MC Marino BS Ravishankar C Dominguez T Godinez RI Dodds KM Ittenbach RF Nicolson SC Bird GL Gaynor JW Spray TL Tabbutt S 《Cardiology in the young》2007,17(6):652-665
The medical records of all patients born between 1 September, 2000, and 31 August, 2002, and undergoing the first stage of Norwood reconstruction, were retrospectively reviewed for details of the perioperative course. We found 99 consecutive patients who met the criterions for inclusion. Hospital mortality for the entire cohort was 15.2%, but was 7.3%, with 4 of 55 dying, in the setting of a "standard" risk profile, as opposed to 25.0% for those with a "high" risk profile, 11 of 44 patients dying in this group. Extracorporeal membrane oxygenation was utilized in 7 patients, with 6 deaths. Median postoperative length of stay in the hospital was 14 days, with a range from 2 to 85 days, and stay in the cardiac intensive care unit was 11 days, with a range from 2 to 85 days. Delayed sternal closure was performed in 18.2%, with a median of 1 day until closure, with a range from zero to 5 days. Excluding isolated delayed sternal closure, and cannulation and decannulation for extracorporeal support, 24 patients underwent 33 cardiothoracic reoperations, including exploration for bleeding in 12, diaphragmatic plication in 4; shunt revision in 4, and other procedures in 13. The median duration of total mechanical ventilation was 4.0 days, with a range from 0.7 to 80.5 days. Excluding those who died, the median total duration of mechanical ventilation was 3.8 days, with a range from 0.9 to 46.3 days. Reintubation for cardiorespiratory failure or upper airway obstruction was performed in 31 patients. Postoperative electroencephalographic and/or clinical seizures occurred in 13 patients, with 7 discharged on anti-convulsant medications. Postoperative renal failure, defined as a level of creatinine greater than 1.5 mg/dl, was present in 13 patients. Eleven had significant thrombocytopenia, with fewer than 20,000 platelets per microl, and injury to the vocal cords was identified in eight patients. Risk factors for longer length of stay included lower Apgar scores, preoperative intubation, early reoperations, reintubation and sepsis, but not weight at birth, genetic syndromes, the specific surgeon, or the duration of surgery.Although mortality rates after the first stage of reconstruction continue to fall, the course in the intensive care unit is remarkable for significant morbidity, especially involving the cardiac, pulmonary and central nervous systems. These patients utilize significant resources during the first hospitalization. Further studies are necessary to stratify the risks faced by patients with hypoplasia of the left heart in whom the first stage of Norwood reconstruction is planned, to determine methods to reduce perioperative morbidity, and to determine the long-term implications of short-term complications, such as diaphragmatic paresis, injury to the vocal cords, prolonged mechanical ventilation, and postoperative seizures. 相似文献
72.
Dobben AC Terra MP Deutekom M Gerhards MF Bijnen AB Felt-Bersma RJ Janssen LW Bossuyt PM Stoker J 《International journal of colorectal disease》2007,22(7):783-790
Background Anal inspection and digital rectal examination are routinely performed in fecal incontinent patients but it is not clear to
what extent they contribute to the diagnostic work-up. We examined if and how findings of anal inspection and rectal examination
are associated with anorectal function tests and endoanal ultrasonography.
Methods A cohort of fecal incontinent patients (n=312, 90% females; mean age 59) prospectively underwent anal inspection and rectal
examination. Findings were compared with results of anorectal function tests and endoanal ultrasonography.
Results Absent, decreased and normal resting and squeeze pressures at rectal examination correlated to some extent with mean (±SD)
manometric findings: mean resting pressure 41.3 (±20), 43.8 (±20) and 61.6 (±23) Hg (p<0.001); incremental squeeze pressure
20.6 (±20), 38.4 (±31) and 62.4 (±34) Hg (p<0.001). External anal sphincter defects at rectal examination were confirmed with
endoanal ultrasonography for defects <90 degrees in 36% (37/103); for defects between 90-150 degrees in 61% (20/33); for defects
between 150-270 degrees in 100% (6/6). Patients with anal scar tissue at anal inspection had lower incremental squeeze pressures
(p=0.04); patients with a gaping anus had lower resting pressures (p=0.013) at anorectal manometry. All other findings were
not related to any anorectal function test or endoanal ultrasonography.
Conclusions Anal inspection and digital rectal examination can give accurate information about internal and external anal sphincter function
but are inaccurate for determining external anal sphincter defects <90 degrees. Therefore, a sufficient diagnostic work-up
should comprise at least rectal examination, anal inspection and endoanal ultrasonography. 相似文献
73.
A climate-driven switch in plant nitrogen acquisition within tropical forest communities 总被引:4,自引:0,他引:4
Houlton BZ Sigman DM Schuur EA Hedin LO 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(21):8902-8906
The response of tropical forests to climate change will depend on individual plant species' nutritional strategies, which have not been defined in the case of the nitrogen nutrition that is critical to sustaining plant growth and photosynthesis. We used isotope natural abundances to show that a group of tropical plant species with diverse growth strategies (trees and ferns, canopy, and subcanopy) relied on a common pool of inorganic nitrogen, rather than specializing on different nitrogen pools. Moreover, the tropical species we examined changed their dominant nitrogen source abruptly, and in unison, in response to precipitation change. This threshold response indicates a coherent strategy among species to exploit the most available form of nitrogen in soils. The apparent community-wide flexibility in nitrogen uptake suggests that diverse species within tropical forests can physiologically track changes in nitrogen cycling caused by climate change. 相似文献
74.
75.
External anal sphincter defects in patients with fecal incontinence: comparison of endoanal MR imaging and endoanal US 总被引:1,自引:0,他引:1
Dobben AC Terra MP Slors JF Deutekom M Gerhards MF Beets-Tan RG Bossuyt PM Stoker J 《Radiology》2007,242(2):463-471
PURPOSE: To prospectively compare in a multicenter study the agreement between endoanal magnetic resonance (MR) imaging and endoanal ultrasonography (US) in depicting external anal sphincter (EAS) defects in patients with fecal incontinence. MATERIALS AND METHODS: The study was approved by the medical ethics committee of all participating centers. A total of 237 consenting patients (214 women, 23 men; mean age, 58.6 years +/- 13 [standard deviation]) with fecal incontinence were examined from 13 different hospitals by using endoanal MR imaging and endoanal US. Patients with an anterior EAS defect depicted on endoanal MR images and/or endoanal US scans underwent anal sphincter repair. Surgical findings were used as the reference standard in the determination of anterior EAS defects. The Cohen kappa statistic and McNemar test were used to calculate agreement and differences between diagnostic techniques. RESULTS: Agreement between endoanal MR imaging and endoanal US was fair for the depiction of sphincter defects (kappa = 0.24 [95% confidence interval: 0.12, 0.36]). At surgery, EAS defects were found in 31 (86%) of 36 patients. There was no significant difference between MR imaging and US in the depiction of sphincter defects (P = .23). Sensitivity and positive predictive value were 81% and 89%, respectively, for endoanal MR imaging and 90% and 85%, respectively, for endoanal US. CONCLUSION: In the selection of patients for anal sphincter repair, both endoanal MR imaging and endoanal US are sensitive tools for preoperative assessment, and both techniques can be used to depict surgically repairable anterior EAS defects. 相似文献
76.
77.
Maria Forlenza Miki Nakao Indra Wibowo Maaike Joerink Joop A.J. Arts Huub F.J. Savelkoul Geert F. Wiegertjes 《Molecular immunology》2009,46(16):3188-3197
Trypanoplasma borreli is an extracellular blood parasite of carp belonging to the same Order (Kinetoplastida) as African trypanosomes. These mammalian parasites have developed different strategies to evade the host immune system including antigenic variation, immunosuppression and clearance of surface-bound antibodies. The latter mechanism allows trypanosomes to use their swimming movement to cause surface-bound antibodies to ‘sail’ and accumulate at the posterior end of the parasite, to be internalized via the flagellar pocket and be degraded. There is no evidence that T. borreli shows antigenic variation, but during the late phases of infection NO-mediated immunosuppression is observed. High levels of nitric oxide (NO) lead to extensive tissue nitration whereas the parasite itself is not affected. Therefore, the induction of NO has thus far been considered a parasite-driven response with immunosuppressive effects. In the present study, we show that the induction of NO, particularly during the early phase of T. borreli infections, should be re-considered an effective part of the host immune response. We show that T. borreli rapidly removes surface-bound IgM. In addition, moderate concentrations of NO, by hindering surface antibody clearance, maintain high the concentrations of membrane-bound IgM, thereby favoring antibody-dependent complement-mediated parasite lysis. We performed a comprehensive quantitative gene expression analysis of in total seven different complement factors involved in all three activation pathways, differentiating between 1 and 4 isoforms for each complement gene. Our gene expression analysis supports an important role for antibody-dependent complement-mediated lysis of T. borreli in vivo. To our knowledge, NO-dependent inhibition of antibody clearance from the surface of kinetoplastid parasites has not been investigated. Our data support a role for NO as an important player in host–parasite interactions, not only as immune suppressor (late response) but also as immune effector (early response) in infections with bloodstream parasites such as T. borreli. 相似文献
78.
Nicolien Hanemaaijer Trijnie Dijkhuizen Maaike Haadsma Margot Boeve Maartje Boon Roel Hordijk Klaas Kok Birgit Sikkema-Raddatz Conny M.A. van Ravenswaaij-Arts 《European journal of medical genetics》2009,52(2-3):116-119
We report on a male patient with intra-uterine growth retardation, microcephaly, coloboma, laryngomalacia and developmental delay. Array CGH analysis revealed a 649 kb duplication on chromosome 1p34.1. Only five patients with overlapping duplications have been reported thus far. Ten known genes are located in the duplicated region, including the POMGNT1 gene encoding for O-mannose beta-1,2-N-acetylglucosaminyltransferase. This gene, mutated in muscle–eye–brain disease, might be causative for the observed phenotype in our patient. 相似文献
79.
Jill Lobbestael Arnoud Arntz Annette Löbbes Maaike Cima 《Journal of behavior therapy and experimental psychiatry》2009,40(4):571-579
The current study assesses whether patients and therapists report similar levels of schema modes, one of the central features in Schema-Focused Therapy. Patient's self-report and therapists' report on an abbreviated Schema Mode Inventory were compared in a sample of 92 patients with antisocial, borderline or cluster C personality disorder. Results indicate a markedly stronger self-therapist discrepancy in mode rating in antisocial patients than in borderline and cluster C patients. Compared to their therapists, ASPD-patients report less presence of most maladaptive modes, whereas there was no difference in adaptive modes. These findings underscore the importance for the use of alternative assessment methods of cognitive concepts in antisocial patients. 相似文献
80.
Clinical correlates of low-risk variants in FGFR2, TNRC9, MAP3K1, LSP1 and 8q24 in a Dutch cohort of incident breast cancer cases 总被引:1,自引:1,他引:0 下载免费PDF全文
Huijts PE Vreeswijk MP Kroeze-Jansema KH Jacobi CE Seynaeve C Krol-Warmerdam EM Wijers-Koster PM Blom JC Pooley KA Klijn JG Tollenaar RA Devilee P van Asperen CJ 《Breast cancer research : BCR》2007,9(6):R78-9