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排序方式: 共有620条查询结果,搜索用时 31 毫秒
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Cameron C Dallaire F Vézina C Muckle G Bruneau S Ayotte P Dewailly E 《Canadian journal of public health. Revue canadienne de santé publique》2008,99(2):102-106
OBJECTIVE: To assess if vitamin A concentration in umbilical cord blood is associated with incidence and severity of respiratory infections in preschool Inuit children from Nunavik (Québec, Canada). METHOD: The medical charts of 305 children were reviewed from 0 to 5 years of age. The association between vitamin A concentration in umbilical cord plasma and the incidence rates of acute otitis media (AOM), lower respiratory tract infections (LRTIs) and hospitalization rates for LRTIs was evaluated using Poisson regression. RESULTS: Compared to children with vitamin A concentration > or =20 microg/dl, adjusted rate ratios (RR) for children below 20 microg/dl ranged between 1.06-1.62 for AOM, 1.12-1.34 for LRTIs, and 1.09-1.43 for hospitalization for LRTIs. Most RRs were statistically significant for AOM and LRTIs, but not for hospitalization for LRTIs. CONCLUSION: Neonatal vitamin A deficiency appears to be a significant risk factor for AOM and LRTIs in this population. 相似文献
124.
Paulsson AK McMullen KP Peiffer AM Hinson WH Kearns WT Johnson AJ Lesser GJ Ellis TL Tatter SB Debinski W Shaw EG Chan MD 《中国神经肿瘤杂志》2013,(1):52-52
PURPOSE: We investigate the patterns of failure in the treatment of glioblastoma(GBM) based on clinical target volume(CTV) margin size,dose delivered to the site of initial failure,and the use of temozolomide and intensity-modulated radiotherapy(IMRT).METHODS: Between August 2000 and May 2010,161 patients with GBM were treated with radiotherapy with or without concurrent temozolomide.Patients were treated with CTV expansions that ranged from 5 to 20 mm using a shrinking field technique.Patterns of failure and time to progression and overall survival were compared based on CTV margin,use of temozolomide,and use of IMRT.Kaplan Meier analysis was used to estimate survival times,and χ test was used for comparison of cohorts.RESULTS: For patients treated with 5-,10-,and 15-to 20-mm CTV,79%,77%,and 86% experienced failures in the 60 Gy volume,respectively.Forty-eight percent,55%,and 66% of patients with 5-,10-,and 15-to 20-mm CTV experienced failures in the 46 Gy volume,respectively.There was no statistical difference between patients treated with 5-,10-,15-to 20-mm margins with regard to 60 Gy failure(P=0.76),46 Gy failure(P=0.51),or marginal failure(P=0.73).Eighty percent of patients receiving temozolomide experienced failures in the 60 Gy volume.There was no increased likelihood of marginal failures in patients receiving IMRT(P =0.97).CONCLUSIONS: Modern treatment techniques including use of concurrent temozolmide,limited CTV margin size,and IMRT have not greatly changed the patterns of failure of GBM. 相似文献
125.
Stachyra T Péchereau MC Bruneau JM Claudon M Frère JM Miossec C Coleman K Black MT 《Antimicrobial agents and chemotherapy》2010,54(12):5132-5138
NXL104 is a potent inhibitor of class A and C serine β-lactamases, including KPC carbapenemases. Native and NXL104-inhibited TEM-1 and P99 β-lactamases analyzed by liquid chromatography-electrospray ionization-time of flight mass spectrometry revealed that the inactivated enzymes formed a covalent adduct with NXL104. The principal inhibitory characteristics of NXL104 against TEM-1 and P99 β-lactamases were determined, including partition ratios, dissociation constants (K), rate constants for deactivation (k(2)), and reactivation rates. NXL104 is a potent inhibitor of TEM-1 and P99, characterized by high carbamylation efficiencies (k(2)/K of 3.7 × 10(5) M(-1) s(-1) for TEM-1 and 1 × 10(4) M(-1) s(-1) for P99) and slow decarbamylation. Complete loss of β-lactamase activity was obtained at a 1/1 enzyme/NXL104 ratio, with a k(3) value (rate constant for formation of product and free enzyme) close to zero for TEM-1 and P99. Fifty percent inhibitory concentrations (IC(50)s) were evaluated on selected β-lactamases, and NXL104 was shown to be a very potent inhibitor of class A and C β-lactamases. IC(50)s obtained with NXL104 (from 3 nM to 170 nM) were globally comparable on the β-lactamases CTX-M-15 and SHV-4 with those obtained with the comparators (clavulanate, tazobactam, and sulbactam) but were far lower on TEM-1, KPC-2, P99, and AmpC than those of the comparators. In-depth studies on TEM-1 and P99 demonstrated that NXL104 had a comparable or better affinity and inactivation rate than clavulanate and tazobactam and in all cases an improved stability of the covalent enzyme/inhibitor complex. 相似文献
126.
127.
Inhibitory synaptogenesis in mouse somatosensory cortex 总被引:4,自引:3,他引:1
It is widely believed that inhibitory synapses are not present or present
in only small numbers in the rodent cerebral cortex during the early
postnatal period when the cortex is being innervated by thalamocortical
fibers. Quantitative electron microscopy was carried out on the
posteromedial barrel subfield of mouse somatosensory cortex from postnatal
day 4 (P4) when thalamocortical innervation of the barrels is becoming
established, through to sexual maturity (>P32), and in adulthood. Both
asymmetrical (putatively excitatory) and symmetrical (putatively
inhibitory) synapses were present in all layers from P4. The symmetrical
synapses were immunoreactive for GABA at all ages. There was a progressive
increase in both asymmetrical and symmetrical synapses up to P32, density
in all layers increasing 16-fold, with the production of asymmetrical
synapses leading and greatly outstripping that of symmetrical. From P32 to
P120, the oldest age studied, synaptic numbers declined by 18% to 13 times
the P4 level, but this affected predominantly layers II/III, IV and V, and
mainly involved asymmetrical synapses. The relative percentage of
asymmetrical to symmetrical synapses from P4 to P8 was 57%/43% but at P32
it was 89.5%/10.5% and in adulthood 85.4%/14.6%. These data indicate that
inhibitory synaptogenesis in the rodent cortex begins earlier than
previously thought, a basis for inhibition being present from the earliest
period. Pruning of all synapses occurs well after thalamocortical
innervation is established and inhibitory synapses are less affected by the
pruning process.
相似文献
128.
J Bruneau Y Cohen L Merlin S Peysson 《International journal of nuclear medicine and biology》1986,12(6):471-476
The rise of the rabbit internal temperature after i.v. injection of an endotoxin solution is proportional to concentration. Gelation of Limulus amoebocyte, when in presence of an endotoxin solution, is also related to concentration. We compared the sensitivity of these two methods. With our experimental procedure, the rabbit is sensitive to a 0.40 ng/mL solution and the Limulus amoebocyte lysate to a 0.14 ng/mL solution. The rabbit sensitivity increase is related to the per kilogramme injected volume, whereas sensitivity is not related to the volume to check in the case of the lysate. 相似文献
129.
130.
L Merlin J Bruneau Y Cohen T Michaud 《International journal of nuclear medicine and biology》1986,12(6):467-470
The rise of the rabbit internal temperature after endotoxin injection is related to the route of administration. A rise of 1.71 +/- 0.411 degrees C is obtained after i.v. injection of 1 ng/kg Escherichia coli 0111.B.4 endotoxin. An increase of 1.93 +/- 0.236 degrees C is obtained after suboccipital intrathecal injection of 0.1 ng/kg of the same endotoxin; with the intrathecal route, the hyperthermia is induced by E. coli endotoxin after a dose ten times lower than with i.v. injection as shown by statistical analysis. 相似文献