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排序方式: 共有356条查询结果,搜索用时 15 毫秒
91.
Denise R Silva Diego M Menegotto Luis F Schulz Marcelo B Gazzana Paulo TR Dalcin 《BMC infectious diseases》2010,10(1):54
Background
To describe the characteristics of patients with tuberculosis (TB) requiring intensive care and to identify the factors that predicts in-hospital mortality in a city of a developing country with intermediate-to-high TB endemicity. 相似文献92.
BackgroundLocked pubic symphysis is an unusual form of pelvic injury. In this the intact pubis gets trapped against contralateral pubis. Closed reduction can be attempted though often requires open reduction and internal fixation. This paper is presented for its rarity and probably first case series on locked pubic symphysis from single institute.Materials and methodsThree cases are presented from the Institute of Orthopaedics and Traumatology, Government General Hospital and Madras Medical College, Chennai from February 2007 to July 2009. Initially closed reduction was attempted but was not possible, so open reduction was planned. Open reduction was successful in all cases with some difficulty and fixed with symphysial plating. All patients were followed up for functional outcome for a mean follow-up of 15 months.DiscussionThis is the first time in the literature a case series of locked pubic symphysis is presented. In all cases it was found that anterior superior iliac spine on the affected side had moved closer to the midline compared to the opposite side. Though suprapubic cystostomy is a contraindication for pfannensteil incision, we have reduced three cases by this incision and done internal fixation with no postoperative wound infection. We were able to reduce the locked pubis with simple maneuvers and with no special distraction instruments. We did not require any osteotomy for the reduction which is a disadvantage as it may produce healing problems.ConclusionLocked pubic symphysis is a rare form of pelvic injury. Though conservative closed reduction maneuvers have been described open reduction is often required. Internal fixation helps not only in stabilizing the anterior rim of pelvis but also the posterior aspect by stabilizing the sacro iliac joint which improves pelvic stability and promotes recovery. 相似文献
93.
EG Gkougkousis M Khan TR Terry JK Mellon 《Annals of the Royal College of Surgeons of England》2009,91(6):532-534
Three cases of recurrent post-coital haematuria are described. Extensive protracted investigations pinpointed urethral varicosities as the likely cause. All patients were successfully treated with diathermy fulguration. 相似文献
94.
95.
TR Miller I Milicic J Bauch J Du B Surber KE Browman K Marsh M Cowart JD Brioni TA Esbenshade 《British journal of pharmacology》2009,157(1):139-149
Background and purpose:
The histamine H3 receptor antagonist radioligand [3H]-A-349821 was characterized as a radiotracer for assessing in vivo receptor occupancy by H3 receptor antagonists that affect behaviour. This model was established as an alternative to ex vivo binding methods, for relating antagonist H3 receptor occupancy to blood levels and efficacy in preclinical models.Experimental approach:
In vivo cerebral cortical H3 receptor occupancy by [3H]-A-349821 was determined in rats from differences in [3H]-A-349821 levels in the isolated cortex and cerebellum, a brain region with low levels of H3 receptors. Comparisons were made to relate antagonist H3 receptor occupancy to blood levels and efficacy in a preclinical model of cognition, the five-trial inhibitory avoidance response in rat pups.Key results:
In adult rats, [3H]-A-349821, 1.5 µg·kg−1, penetrated into the brain and cleared more rapidly from cerebellum than cortex; optimally, [3H]-A-349821 levels were twofold higher in the latter. With increasing [3H]-A-349821 doses, cortical H3 receptor occupancy was saturable with a binding capacity consistent with in vitro binding in cortex membranes. In studies using tracer [3H]-A-349821 doses, ABT-239 and other H3 receptor antagonists inhibited H3 receptor occupancy by [3H]-A-349821 in a dose-dependent manner. Blood levels of the antagonists corresponding to H3 receptor occupancy were consistent with blood levels associated with efficacy in the five-trial inhibitory avoidance response.Conclusions and implications:
When employed as an occupancy radiotracer, [3H]-A-349821 provided valid measurements of in vivo H3 receptor occupancy, which may be helpful in guiding and interpreting clinical studies of H3 receptor antagonists. 相似文献96.
V Thulasiraman TR Ramesh Pandian S Cheralathan S Ashok 《Indian Journal of Orthopaedics》2010,44(4):471-473
Idiopathic internal jugular phlebectasia, occurs either unilaterally or bilaterally affecting the internal jugular vein is a rare congenital variation often diagnosed during childhood. It usually presents with a benign swelling over the lateral side of neck on the affected side, seen on exertion. A-30-year old male was operated for anterior cervical dissectomy from right lateral approach and was diagnosed per-operatively as internal jugular phlebectasia. The surgery was abandoned at this stage on the advice of cardiothoracic surgeon to investigate the patient for the secondary etiological factors for internal jugular vein dilatation. The patient was reassured without any active intervention for the phlebectasia and cervical dissectomy was performed in the second surgery through the lateral approach from left side. This case is presented in view of rarity and suggested that during preoperative workup the nearby structures like carotid sheath should be evaluated by magnetic resonance imaging to avoid such per-operative surprises. 相似文献
97.
Identification of the functional core of the influenza A virus A/M2 proton-selective ion channel
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Chunlong Ma Alexei L. Polishchuk Yuki Ohigashi Amanda L. Stouffer Arne Sch?n Emma Magavern Xianghong Jing James D. Lear Ernesto Freire Robert A. Lamb William F. DeGrado Lawrence H. Pinto 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(30):12283-12288
The influenza A virus M2 protein (A/M2) is a homotetrameric pH-activated proton transporter/channel that mediates acidification of the interior of endosomally encapsulated virus. This 97-residue protein has a single transmembrane (TM) helix, which associates to form homotetramers that bind the anti-influenza drug amantadine. However, the minimal fragment required for assembly and proton transport in cellular membranes has not been defined. Therefore, the conductance properties of truncation mutants expressed in Xenopus oocytes were examined. A short fragment spanning residues 21–61, M2(21-61), was inserted into the cytoplasmic membrane and had specific, amantadine-sensitive proton transport activity indistinguishable from that of full-length A/M2; an epitope-tagged version of an even shorter fragment, M2(21-51)-FLAG, had specific activity within a factor of 2 of the full-length protein. Furthermore, synthetic fragments including a peptide spanning residues 22–46 were found to transport protons into liposomes in an amantadine-sensitive manner. In addition, the functionally important His-37 residue pKa values are highly perturbed in the tetrameric form of the protein, a property conserved in the TM peptide and full-length A/M2 in both micelles and bilayers. These data demonstrate that the determinants for folding, drug binding, and proton translocation are packaged in a remarkably small peptide that can now be studied with confidence. 相似文献
98.
TR Villa AR Correa Moutran LA Sobirai Diaz MM Pereira Pinto FA Carvalho AA Gabbai & D de Souza Carvalho 《Cephalalgia : an international journal of headache》2009,29(6):631-634
The aim of this study was to evaluate the visual attention of children with migraine and compare it with a control group. Thirty migrainous children and 30 controls without headache were subjected to a visual attention assessment with Trail Making Tests (TMT) A/B, Letter Cancellation Test, and the Brazilian computerized test Visual Attention Test, third edition. The migraine group was evaluated after 2 days without headache. The migraine group had an inferior performance compared with the control group on TMT A ( P = 0.03) and B ( P = 0.001), and more errors on tasks 1 ( P = 0.032) and 2 ( P = 0.015) of the Visual Attention Test, presenting difficulty with selective and alternate attention. Attention is a neurological function that depends on structures such as the brainstem, cerebral cortex and the limbic system and on neurotransmitters such as dopamine and noradrenaline. The neurochemical aspects involved in the physiopathology of migraine and attention mechanisms probably predispose these children to visual attention deficits. 相似文献
99.
100.
The two-dimensional IR nonlinear spectroscopy of a cyclic penta-peptide in relation to its three-dimensional structure 总被引:1,自引:0,他引:1
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Hamm P Lim M DeGrado WF Hochstrasser RM 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(5):2036-2041
A form of two-dimensional (2D) vibrational spectroscopy, which uses two ultrafast IR laser pulses, is used to examine the structure of a cyclic penta-peptide in solution. Spectrally resolved cross peaks occur in the off-diagonal region of the 2D IR spectrum of the amide I region, analogous to those in 2D NMR spectroscopy. These cross peaks measure the coupling between the different amide groups in the structure. Their intensities and polarizations relate directly to the three-dimensional structure of the peptide. With the help of a model coupling Hamiltonian, supplemented by density functional calculations, the spectra of this penta-peptide can be regenerated from the known solution phase structure. This 2D-IR measurement, with an intrinsic time resolution of less than 1 ps, could be used in all time regimes of interest in biology. 相似文献