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61.
C G Gross 《Neuropsychologia》1991,29(6):497-515
We studied the visual responses of single neurons in three extra-striate visual areas of the macaque following lesions of striate cortex, lesions of the tecto-pulvinar system or both. After striate lesions, there was (a) considerable specific activity remaining in area MT including direction selectivity, (b) only non-specific activity in the superior temporal polysensory area (STP), and (c) no visual responsiveness at all in inferior temporal cortex (IT). In animals with striate lesions, interruption of the tecto-pulvinar pathway eliminated the residual visual activity in MT and STP that survived the striate lesions. Interruption of the tecto-pulvinar pathway alone had little or no effect on visual evoked activity in any of the three areas. These results are related to the relative dependence of visual responsiveness in MT, STP and IT on striate cortex and the superior colliculus, to differences between the dorsal and ventral cortical processing streams, and to neural mechanisms underlying blind sight. 相似文献
62.
Severe tubulopathy and kidney graft rupture after coadministration of mannitol and ciclosporin. 总被引:2,自引:0,他引:2
G Biesenbach J Zazgornik W Kaiser P Grafinger U Stuby C Gross P Hartl P Brücke 《Nephron》1992,62(1):93-96
Spontaneous allograft rupture after kidney transplantation is a rare complication usually due to an acute rejection of the interstitial type. In a 32-year-old man kidney transplantation was performed under immunosuppression with prednisolone and ciclosporin (CS). The dose of CS was 5 mg/kg body weight intravenously for the first 24 h, on the 2nd day 10 mg/kg/day orally, with gradually decreasing doses thereafter. The patient remained oliguric in the postoperative period and received additionally 600 ml mannitol solution intravenously for osmodiuresis within a period of 6 days. On the 8th postoperative day, 48 h after the last intravenous infusion of mannitol, spontaneous renal rupture occurred. The CS concentrations in the blood during the days before the rupture were within the upper normal range for effective immunosuppression (300-600 ng/ml). Intraoperatively the kidney appeared enlarged due to edematous swelling of the graft, but it showed no signs of rejection. The histological finding was a toxic tubulopathy with extensive isometric vacuolization and peritubular congestion, a known side effect of both of CS and of mannitol. The rupture was successfully repaired. Thirty-four days after the transplantation diuresis increased and hemodialysis therapy could be discontinued. In a second biopsy of the kidney the signs of toxic tubulopathy with isometric vacuolization were reduced. On the following days the serum creatinine dropped below 160 mumol/l. It can be assumed that the combination of CS therapy and administration of massive and continued doses of mannitol in an oliguric patient with allograft kidney may potentiate severe tubulopathy with concomitant edematous swelling of the graft. This can result in an increasing danger of spontaneous renal rupture. 相似文献
63.
The new thromboxane A2 antagonist [3H]BAY U 3405 was characterized for its binding to washed human platelets and platelet membranes. In washed platelets the specific binding was reversible, selective and stereospecific, but not saturable. The dissociation constant (Kd) was 6 +/- 2.5 nM, the number of specific binding sites 1177 +/- 306 per platelet. Three structurally different thromboxane A2 (TXA2)/prostaglandin H2 (prostaglandin endoperoxide) (PGH2) receptor ligands completely inhibited the specific binding of [3H]BAY U 3405 in a concentration-dependent manner, indicating that the observed high affinity binding site is the TXA2/PGH2 receptor. In platelet membranes, however, specific [3H]BAY U 3405 binding showed saturability in addition to reversibility, selectivity, and stereospecifity. The Kd of the binding was 9.6 +/- 2.3 nM in kinetic studies and 8.7 +/- 3.7 nM in saturation studies, the inhibition constant (Ki) was 10 +/- 1.1 nM in displacement studies. The TXA2/PGH2 receptor agonists U 46619 and CTA2, and the antagonists Daltroban (BM 13505), I-PTA-OH and SQ 29548 all completely inhibited the specific binding of [3H]BAY U 3405 thus defining the observed binding site as the TXA2/PGH2 receptor. In conclusion, the data suggest that the previously reported TXA2 antagonism of BAY U 3405 is mediated by binding to a specific high affinity binding site of human platelets and platelet membranes that represents the TXA2/PGH2 receptor. 相似文献
64.
Background
Many studies have found socioeconomic differentials in cancer survival. Previous studies have generally demonstrated poorer cancer survival with decreasing socioeconomic status but mostly used only ecological measures of status and analytical methods estimating simple survival. This study investigate socio-economic differentials in cancer survival using four indicators of socioeconomic status; three individual and one ecological. It uses a relative survival method which gives a measure of excess mortality due to cancer. 相似文献65.
P Froom J Benbassat M Gross J Ribak B S Lewis 《Aviation, space, and environmental medicine》1988,59(3):278-281
The epidemiology of sudden death, the etiology of inflight sudden incapacitation, and the influence of pilot age and experience on air accident rates are reviewed in order to determine the aeromedical emphasis needed to minimize accidents. Sudden deaths in men over age 35 are nearly all due to coronary artery disease, whereas in those under 35 years they are mostly due to hypertrophic cardiomyopathy. The incidence of fatal accidents from human error is, however, far greater than that from physical illness. Since inexperienced pilots have a 2-3 times increased incidence of mishaps due to pilot error, the estimated risk of disease related in-flight sudden incapacitation should be balanced by consideration of pilot experience. Therefore, it may be preferable to grant waivers to experienced pilots with an increased incidence of disease-related inflight sudden incapacitation than to replace them with novices. We conclude that overly strict medical criteria may paradoxically increase accident rates. 相似文献
66.
Wilson's disease tremor is associated with magnetic resonance imaging lesions in basal ganglia structures. 总被引:1,自引:0,他引:1
Martin Südmeyer Andreas Saleh Lars Wojtecki Mathias Cohnen Joachim Gross Markus Ploner Harald Hefter Lars Timmermann Alfons Schnitzler 《Movement disorders》2006,21(12):2134-2139
Wilson's disease (WD) is an inherited disorder of copper metabolism yielding marked motor deficits, including a severely disabling tremor. As a structural correlate of the disease, a variety of cerebral abnormalities has been revealed. However, the relationship between motor deficits and cerebral lesions has remained largely unknown. Here, we investigated correlation between WD tremor and cerebral magnetic resonance imaging (MRI) findings. Cerebral MRI abnormalities in 6 symptomatic WD patients were compared to findings in 6 asymptomatic WD patients and 10 healthy controls. All patients were treated with long-term copper chelating therapy. Motor symptoms including tremor were determined by Unified Parkinson's Disease Rating Scale Part III (UPDRS-III). MRI findings in symptomatic WD patients revealed significant symmetric T2*-weighted hypointense signal alterations of globus pallidus, head of the caudate nucleus, and substantia nigra. In contrast, MRI of asymptomatic WD patients did not differ from healthy controls. Correlation analysis revealed a significant positive correlation between MRI basal ganglia lesions and UPDRS action tremor score. Our results demonstrate for the first time that Wilson's disease tremor is associated with lesions of the globus pallidus, the head of the caudate nucleus, and the substantia nigra. 相似文献
67.
Ahmad Y. Sheikh MD ; Mark D. Rollins MD PhD ; Harriet W. Hopf MD ; Thomas K. Hunt MD 《Wound repair and regeneration》2005,13(3):303-308
There is a need for a noninvasive method that measures wound angiogenesis. Hyperoxia is known to increase the appearance of new blood vessels in wounds, yet no study has confirmed increases in wound bed perfusion with periodic hyperbaric oxygen (HBO) exposure. This study investigates whether laser Doppler imaging is able to detect and quantify the enhancement of wound angiogenesis that is known to occur with intermittent HBO treatments. Full-thickness dorsal dermal wounds were created on mice randomized to hyperoxic (n = 14) and control (n = 15) groups. Hyperbaric oxygen was administered twice daily for 90 minutes each at 2.1 atmospheres for 7 days. Wound bed perfusion was measured by laser Doppler imaging on days 0, 7, and 10 postwounding. Wound blood flow increased significantly over baseline on day 7 and 10 in the hyperoxic group, but only on day 10 in the control group. Comparison between groups showed a 20% statistically significant increase in wound perfusion in HBO-treated animals compared to control on day 10 (p = 0.05). Laser Doppler imaging was able to detect and quantify the increase in wound bed perfusion resulting from intermittent HBO treatments and shows promise as a noninvasive measure of angiogenesis and wound healing. 相似文献
68.
Felix Matthews Valentin Neuhaus Daniel Schmucki Ronald Schwyn Thomas Gross Pietro Regazzoni Otmar Trentz Peter Messmer 《European Journal of Trauma》2005,31(6):568-574
Abstract During treatment of femoral shaft fractures, not only the actual fracture reduction but also the retention of the achieved
reduction is essential. Substantial forces may apply to the bone fragments, due to multidirectional muscular contraction.
Furthermore, forces from manipulation of one bone fragment may be transferred over the soft tissues onto the other fragments,
thus hindering accurate fracture reduction. Once a sufficient reduction has been achieved, this position must be retained
whilst definitive internal fixation is performed. Conventional methods comprise mounting patients on a traction table and
applying manual distraction or employing special distraction devices, such as the AO distractor device. These approaches,
however, only insufficiently stabilize both main fragments. For example, on the traction table the proximal femoral fragment
can pivot around the hip joint thus complicating precise reduction. A novel pneumatic stabilization device to assist surgeons
during operative procedures is described. This passive holding device “Passhold” connects to one main fragment through a minimally
invasive bone interface and statically locks the fragment’s position. Thereafter, only the other main fragment is manipulated
to achieve reduction. Mutual interference of the reciprocal fragment positions, due to soft-tissue force transfer during manipulation,
is avoided. The authors examined the stability of the novel retention device on a test rig and proved its functionality under
sterile settings using cadaver tests. It is concluded that this device largely facilitates the operative procedure in femoral
shaft fractures, is sufficiently stable and ergonomically suitable for intraoperative deployment. 相似文献
69.
The effectiveness of interdisciplinary treatments for chronic pain is well established. In general, these treatments decrease psychosocial distress and increase physical abilities. Further, return to work rates following interdisciplinary treatment tend to be quite high. Previous studies have highlighted a number of factors that individually influence return to work rates; however, there is a need for more comprehensive and unified models that allow an evaluation of the inter-relations among these factors. The present investigation examined how demographic and treatment outcome variables interacted to influence post-treatment return to work rates in a sample of individuals with chronic pain following interdisciplinary treatment. Results indicated that patient age, lifting ability, pain duration, depression level, and reported disability were individually related to return to work; however, when these variables were evaluated relative to one another, level of depression and patient age had the best ability to predict post-treatment work status. These results add to the literature by specifically highlighting post-treatment factors that best discriminate patients who had returned to work from those that had not. Furthermore, they provide evidence that general emotional distress is perhaps the most important predictor of work status following treatment. 相似文献
70.