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1.
We report a patient with unilateral damage to the rostral part of the pulvinar who was impaired in localizing stimuli in the inferior visual field contralateral to the lesion and who made errors in the binding of shape and color in that quadrant. The findings demonstrate the importance of the pulvinar in spatial coding and provide support for the function of the thalamus in binding of features. They also provide evidence for a homology between the visual field maps of the inferior and lateral subdivisions of the pulvinar in monkeys and in humans, such that the inferior visual field is represented in the rostral part of the nucleus.  相似文献   
2.
Machado L  Rafal RD 《Neuroreport》1999,10(15):3143-3148
The current study investigated whether an ipsilesional bias in line bisection, a conventional measure for diagnosing hemispatial neglect, persists even in the absence of this syndrome in patients with chronic lesions restricted to posterior association cortex or dorsolateral prefrontal cortex. Both left and right hemisphere parietal lesions produced ipsilesional bisection errors, and to a comparable degree. Patients with lesions in frontal cortex, on the other hand, did not show a consistent bias. We conclude that chronic parietal lesions produce an ipsilesional bias in line bisection, even in the absence of other clinical signs of neglect, and that left hemisphere lesions can affect line bisection to the same degree as right hemisphere lesions.  相似文献   
3.
PURPOSE: Prostate-specific membrane antigen (PSMA) is a cell surface protein that is overexpressed in prostate cancer, including hormone-refractory and metastatic disease. Our goal in this study was to develop a series of PSMA-based imaging agents for clinical use. EXPERIMENTAL DESIGN: We have synthesized and evaluated the in vivo biodistribution of two radiolabeled urea derivatives that have high affinity for PSMA in severe combined immunodeficient mice harboring MCF-7 (breast, PSMA-negative), PC-3 (prostate, PSMA-negative), and LNCaP (prostate, PSMA-positive) xenografts. Radiopharmaceutical binding selectivity and tumor uptake were also evaluated in vivo using dedicated small animal positron emission tomography, single photon emission computed tomography, and gamma scintigraphic imaging devices. N-[N-[(S)-1,3-dicarboxypropyl]carbamoyl]-S-[(11)C]methyl-L-cysteine ([(11)C]DCMC K(i), 3.1 nmol/L) and N-[N-[(S)-1,3-dicarboxypropyl]carbamoyl]-S-3-[(125)I]iodo-L-tyrosine ([(125)C]DCIT K(i), 1.5 nmol/L) were synthesized using [(11)C]CH(3)I and with [(125)I]NaI/Iodogen, respectively.RESULTS: At 30 minutes postinjection, [(11)C]DCMC and [(125)I]DCIT showed tumor/muscle ratios of 10.8 and 4.7, respectively, with clear delineation of LNCaP-derived tumors on imaging. MCF-7- and PC-3-derived tumors showed significantly less uptake of [(11)C]DCMC or [(125)I]DCIT. CONCLUSION: These results show the feasibility of imaging PSMA-positive prostate cancer using low molecular weight agents.  相似文献   
4.
BackgroundShared and divergent predictors of clinical severity across respiratory viruses may support clinical and community responses in the context of a novel respiratory pathogen.MethodsWe conducted a retrospective cohort study to identify predictors of 30‐day all‐cause mortality following hospitalization with influenza (N = 45,749; 2010‐09 to 2019‐05), respiratory syncytial virus (RSV; N = 24 345; 2010‐09 to 2019‐04), or severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2; N = 8988; 2020‐03 to 2020‐12; pre‐vaccine) using population‐based health administrative data from Ontario, Canada. Multivariable modified Poisson regression was used to assess associations between potential predictors and mortality. We compared the direction, magnitude, and confidence intervals of risk ratios to identify shared and divergent predictors of mortality.ResultsA total of 3186 (7.0%), 697 (2.9%), and 1880 (20.9%) patients died within 30 days of hospital admission with influenza, RSV, and SARS‐CoV‐2, respectively. Shared predictors of increased mortality included older age, male sex, residence in a long‐term care home, and chronic kidney disease. Positive associations between age and mortality were largest for patients with SARS‐CoV‐2. Few comorbidities were associated with mortality among patients with SARS‐CoV‐2 as compared with those with influenza or RSV.ConclusionsOur findings may help identify patients at greatest risk of illness secondary to a respiratory virus, anticipate hospital resource needs, and prioritize local prevention and therapeutic strategies to communities with higher prevalence of risk factors.  相似文献   
5.
Tick-borne diseases are a serious threat to both public and veterinary health. In this study, we used high-throughput sequencing to characterize the virome of three tick species implicated in the spread of vector-borne disease throughout Croatia. Ten viruses were identified, including seven potential novel species within the viral families Flaviviridae, Nyamiviridae, Rhabdoviridae, Peribunyaviridae, Phenuiviridae, and Nairoviridae.  相似文献   
6.
Wound healing and skin tissue regeneration remain the most critical challenges faced by medical professionals. Titanium(IV) oxide-based materials were proposed as components of pharmaceutical formulations for the treatment of difficult-to-heal wounds and unsightly scarring. A gallic acid-functionalized TiO2 nanomaterial (TiO2-GA) was obtained using the self-assembly technique and characterized using the following methods: scanning electron microscopy (SEM), transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), X-ray powder diffraction (XRPD), infrared spectroscopy (IR), Raman spectroscopy and thermogravimetry (TG). Additionally, physicochemical and biological tests (DPPH assay, Microtox® acute toxicity test, MTT assay) were performed to assess antioxidant properties as well as to determine the cytotoxicity of the novel material against eukaryotic (MRC-5 pd19 fibroblasts) and prokaryotic (Staphylococcus aureus, Escherichia coli, Candida albicans, Aliivibrio fischeri) cells. To determine the photocytotoxicity of the material, specific tests were carried out with and without exposure to visible light lamps (425 nm). Following the results, the TiO2-GA material could be considered an additive to dressings and rinsing suspensions for the treatment of difficult-to-heal wounds that are at risk of bacterial infections.  相似文献   
7.
Successful total knee arthroplasty is dependent on the correct alignment of implanted prostheses. Major clinical problems can be related to poor femoral component positioning, including sagittal plane and rotational malalignment. A prospective randomized study was designed to test whether an optical navigation system for total knee arthroplasty achieved greater implantation precision than a nonnavigated technique. The primary variable was rotation of the femoral component in the transverse plane, measured from postoperative radiographs and computed tomography images. Sixty-four patients were included in the study. All patients received the Duracon total knee prosthesis. The patients were randomly divided into two groups: Group C patients had conventional total knee arthroplasty without navigation; Group N patients had total knee arthroplasty using a computer-assisted knee navigation system. Analysis showed that patients in Group N had significantly better rotational alignment and flexion angle of the femoral component than patients in Group C. In addition, superior postoperative alignment of the mechanical axis, posterior tibial slope, and rotational alignment was achieved for patients in Group N. The use of a navigation system provides improved alignment accuracy, and can help to avoid femoral malrotation and errors in axial alignment.  相似文献   
8.
Introduction  The treatment of neurogenic dysfunctions of micturition, both surgical and conservative, aims primarily to protect upper urinary tract function. This goal can be achieved by lowering intravesical pressure and increasing urinary bladder capacity in the urine collection phase or by facilitating bladder emptying. Objective  The objective of this paper was to assess the outcome of transcutaneous stimulation of the urinary bladder in the treatment of neurogenic disorders of micturition. Materials and methods  The effect of urinary bladder stimulation was assessed in 22 patients (4 females, 18 males) with spinal injuries (19 with injuries to the lumbo-sacral spine and 3 with cervical spine injuries) treated at the Department of Rehabilitation of the Military Hospital in Bydgoszcz, Poland, in 2006 and 2007. The treatment consisted of 30 procedures of transcutaneous electrical stimulation of the urinary bladder. A pulsed sinusoid current was used with a pulse duration of 200 ms, break duration of 1,000 ms, intensity of 15–20 mA, frequency of 50 Hz, and duration of stimulation of 15 min. A urodynamic study was carried out in each patient at baseline and on completion of the electrical stimulation therapy (immediately and after 2 months). Results  Electrical stimulation of the neurogenic urinary bladder produced increases in the cystometric bladder capacity and reduction in the amount of residual urine (72% of patients), with reduction of intravesical pressure at peak urine flow (59% of the patients). The dynamic aspects of micturition also improved with increased peak voiding velocity in 77.3% of the patients. More than half of the patients (57%) still had elevated intravesical pressures during micturition that posed a risk to the function of the upper urinary tract despite significant decreases following the stimulation therapy. Micturition, which was absent at baseline, was restored in three patients. No local complications were observed. Conclusions  Transcutaneous electrical stimulation of the urinary bladder in patients with neurogenic bladder dysfunction improves lower urinary tract function. Urodynamic studies executed 2 months after finishing TES show persistent results.  相似文献   
9.
The effect of melatonin on glucose metabolism in the presence and absence of insulin has been investigated in the primary cultures of renal tubules grown in a defined medium. In the absence of glucose in the medium containing 5 microg/mL of insulin and 2 mm alanine + 5 mm glycerol + 0.5 mm octanoate, 100 nm melatonin stimulated both glucose and lactate synthesis, while in the medium devoid of insulin melatonin action was negligible. Melatonin-induced increase in glucose and lactate synthesis was accompanied by an enhancement of alanine and glycerol consumption. In view of measurements of [U-14C]L-alanine and [U-14C]L-glycerol incorporation into glucose, it is likely that melatonin increased alanine utilization for glucose production, while accelerated lactate synthesis was because of an enhanced glycerol consumption. As (i) 10 nm luzindole attenuated the stimulatory action of melatonin on glucose formation and (ii) the indole induced a decrease in intracellular cAMP level, it seems likely that in renal tubules melatonin binds to ML1 membrane receptor subtype. In view of a decline of intracellular fructose-1,6-bisphosphate content accompanied by a significant rise in hexose-6-phosphate and glucose levels, melatonin might result in an acceleration of flux through fructose-1,6-bisphosphatase probably because of an increase in the active, dephosphorylated form of this enzyme. Thus, the administration of melatonin in combination with insulin might be beneficial for diabetic therapy because of protection against hypoglycemia.  相似文献   
10.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inheritant disease with an autosomal dominant mode of transmission with incomplete penetrance and variable expression. Linkage analysis in affected families succeeds in identifying 9 loci determining 9 subtypes of the disease. Genotype phenotype correlation is unclear and the influence of various environmental factors is discussed. OBJECTIVES: Genotype phenotype correlation in 2 pairs of monozygotic twins with ARVC and the role of environmental factors are analyzed. PATIENTS AND METHODS: Among 40 pts with ARVC and their 195 relatives there were 2 pairs of monozygotic twins: brothers, age 47 y; and sisters, age 48 y. History, ECG, Holter monitoring, 2D and Doppler Echo, and MRI were analyzed. RESULTS: Twin brothers: ARVC was diagnosed in the proband after the episode of VT with LBBB morphology (enlarged right ventricle, focal hypokinesia of apex, MR evidence of adipose tissue in RV wall). Identical morphology of RV was seen in asymptomatic twin brother. The patient presenting arrhythmia has been rowing for 4 years. Twin sisters: diagnosis was done during family screening. Both were asymptomatic. RV morphology typical for ARVC was found discrete in one of them (bulges adipose tissue in the RV apex); the latter showed changes suggesting RV abnormality (mild segmental dilatation of infundibulum, adipose tissue in a free wall of the RV). No differences in previous viral infections and sports involvement were observed. CONCLUSIONS: 1. Clinical picture of ARVC in monozygotic twins is not identical. 2. Strenuous effort may be a factor triggering the arrhythmia in pts with ARVC.  相似文献   
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