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101.
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
102.
103.
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104.
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
105.
106.
Gelzleichter TR; Bermudez E; Mangum JB; Wong BA; Janszen DB; Moss OR; Everitt JI 《Toxicological sciences》1999,49(1):93-101
The present study was designed to determine whether pleural fiber burdens
or subchronic pleural fibroproliferative and inflammatory changes can help
explain the marked interspecies differences in pleural fibrosis and
mesothelioma that are observed following long-term inhalation of RCF-1
ceramic fibers by rats and hamsters. Fischer 344 rats and Syrian golden
hamsters were exposed to RCF-1 for 4 h per day, 5 days per week, for 12
consecutive weeks. Lung and pleural fiber burdens were characterized during
and after exposure. For all time points, approximately 67% of fibers
associated with lung tissues from both rats and hamsters were longer than 5
microns in length. In comparison, fibers longer than 5 microns recovered
from the pleural compartment, following a 12-week exposure and 12 weeks of
recovery, accounted for 13% (hamsters) and 4% (rats) of the distribution.
In the 12 weeks after the cessation of exposure, the number of fibers
longer than 5 microns in length remained constant in the hamster at
approximately 150 fibers per cm2 pleura. This was 2 to 3 times the
corresponding fiber surface density in the rat. Significant pulmonary and
pleural inflammation was detected at all time points and for both species.
DNA synthesis by pleural mesothelial cells was quantified by
bromodeoxyuridine uptake following 3 days of labeling. Labeling indices
were higher in hamsters than in rats, both for RCF-1-exposed and filtered
air-control animals and was highest for the parietal surface of the pleura.
Significantly greater collagen deposition was measured in the visceral
pleura of hamsters 12 weeks post-exposure but was not significantly
elevated in rats. These findings demonstrate that subchronic inhalation
exposure to RCF-1 induces pleural inflammation, mesothelial-cell turnover,
pleural fibrosis, and an accumulation of fibers with a length greater than
5 microns in the hamster. The accumulation of long fibers in the pleural
space may contribute to the pathology observed in the hamster following
chronic inhalation of RCF- 1, whereas the presence of short, thin fibers
may play a role in the acute-phase biological response seen in both
species.
相似文献
107.
108.
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109.
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
110.
Therapeutic angiogenesis in chronically ischemic porcine myocardium: comparative effects of bFGF and VEGF 总被引:14,自引:0,他引:14
Hughes GC Biswas SS Yin B Coleman RE DeGrado TR Landolfo CK Lowe JE Annex BH Landolfo KP 《The Annals of thoracic surgery》2004,77(3):812-818
BACKGROUND: Both vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) have been used in preclinical studies to induce new blood vessel growth in ischemic cardiac muscle with promising results. However, clinical trials have been much less convincing and further work is needed. This study expands on prior work by comparing the long-term proangiogenic effects of direct intramyocardial (IM) injection of bFGF, as well as IM and intravenous (IV) VEGF in a porcine model of chronic hibernating myocardium. METHODS: Mini-swine with proximal 90% left circumflex (LCx) coronary stenosis subtending chronically ischemic, viable (hibernating) myocardium by positron emission tomography (PET) and dobutamine stress echocardiography (DSE) were randomized to IM bFGF (n = 5), IM VEGF(165) (n = 5), IV VEGF(165) (n = 5), IM vehicle (n = 5), or sham redo-thoracotomy (n = 4). The bFGF protein was administered in a total dose of 1.35 microg divided into 30 IM injections. IM VEGF(165) protein was administered in a total dose of 15 microg/kg divided into 30 injections; IV VEGF(165) was given at a dose of 50 ng. kg(-1). min(-1) for 200 minutes at three 72-hour intervals (30 microg/kg total dose). After 3 and 6 months the PET and DSE studies were repeated, and the animals were sacrificed for tissue vascular density and angiogenic protein analysis. RESULTS: Myocardial blood flow (MBF) by PET was significantly improved 3 months posttreatment in the IM bFGF and IM VEGF(165) groups, differences that were sustained at 6 months. There was no significant increase in MBF 3-months posttreatment in the IV VEGF(165) group; however, at 6 months MBF was significantly improved. No change in MBF was seen in the IM vehicle or sham groups. Regional wall motion at rest and peak stress in the LCx region demonstrated small but statistically significant improvements by 6 months in the IM bFGF and IV VEGF(165) groups only; no improvement was seen in the IM VEGF(165), IM vehicle, or sham groups. Quantitative vascular density was significantly increased in the LCx regions of all treatment groups (IM bFGF, IM VEGF(165), IV VEGF(165)) 6-months postoperatively. No significant increase in LCx region myocardial bFGF or VEGF protein levels was seen in the treated animals at 6 months. CONCLUSIONS: The IM bFGF, IM VEGF(165), and IV VEGF(165) all improve regional perfusion and vascular density 6-months posttherapy in the animal model utilized. Functional improvements were less consistent. Both bFGF and VEGF(165) may be useful therapies for improving regional perfusion in chronically ischemic myocardium, although combination therapy with additional growth factors or cellular therapies may be necessary if concomitant improvements in function are to be seen. 相似文献