首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Sensorimotor responses to stimulation of the medical frontal and cingulate area were studied in seven unrestrained, unsedated patients who suffered from intractable seizures. Complex postural synergies involving the trunk and proximal extremities appeared contralaterally or occasionally bilaterally. Contraversive turning of head and eyes was not observed. Sensory responses from the supplementary motor area were referred contralaterally and focally; those from the cingulate gyrus were widely referred. Speech impairment from stimulation of the supplementary motor area showed striking similarities with that obtained from stimulation in the frontostriatal region or lateral aspect of the frontal lobe. The observations support the hypothesis that interference with striatal function may be the basis of speech inhibition produced by stimulation of the frontal lobe.  相似文献   

2.
Following a case of traumatic rupture of the 3 lobes of the right lung without any parietal lesion, the authors found three similar cases in the literature. However, uni or bilobar rupture was more frequently described. The pathological mechanisms are considered. The treatment of these lesions, in contrast to pulmonary laceration due to fractured ribs, most often requires limited parenchymal excision.  相似文献   

3.
The lobes of the human prostate.   总被引:1,自引:0,他引:1  
A dissection technique for the huamn prostate has been developed on about one hundred male autopsies, which makes it possible to delimit two dorsal, two lateral and two median lobes, each with separate ducts. It was found that both the dorsal lobesand the lateral lobes join dorsally to the ejaculatory ducts. The median lobes are situated below the medial parts of the seminal vesicles, and are closely apposed both ventrally and dorsally of the ejaculatory ducts. The ability to delimit the prostatic lobes in man may offer new opportunities to study the relation of prostatic diseases to different lobes as well as the hormonal dependency of the separate lobes.  相似文献   

4.
The control and allocation of attention is an essential, ubiquitous neural process that gates our awareness of objects and events in the environment. Neural representations of the locus of spatial attention have been previously demonstrated in parietal cortex. However, the behavioral relevance of these neural representations is not known. While undergoing functional magnetic resonance imaging, subjects performed a covert spatial attention task that yielded a wide range of performance values. Voxels in parietal cortex selective for attended target location also dynamically modulated, becoming more or less responsive as performance levels changed. Surprisingly, this relationship was not linear. Responses peaked at intermediate performance levels and dropped both when performance was very high and when it was very low. Such dynamic modulation may represent a mechanism for organizing neural control signals according to behavioral task demands.  相似文献   

5.
Asymmetrical specialization of cognitive processes across the cerebral hemispheres is a hallmark of healthy brain development and an important evolutionary trait underlying higher cognition in humans. While previous research, including studies of priming, divided visual field presentation, and split-brain patients, demonstrates a general pattern of right/left asymmetry of form-specific versus form-abstract visual processing, little is known about brain organization underlying this dissociation. Here, using repetition priming of complex visual scenes and high-resolution functional magnetic resonance imaging (MRI), we demonstrate asymmetrical form specificity of visual processing between the right and left hemispheres within a region known to be critical for processing of visual spatial scenes (parahippocampal place area [PPA]). Next, we use resting-state functional connectivity MRI analyses to demonstrate that this functional asymmetry is associated with differential intrinsic activity correlations of the right versus left PPA with regions critically involved in perceptual versus conceptual processing, respectively. Our results demonstrate that the PPA comprises lateralized subregions across the cerebral hemispheres that are engaged in functionally dissociable yet complementary components of visual scene analysis. Furthermore, this functional asymmetry is associated with differential intrinsic functional connectivity of the PPA with distinct brain areas known to mediate dissociable cognitive processes.  相似文献   

6.
7.
The authors report a very rare case of lipome extended to the superficial and deep lobes of parotid gland. MRI remains the best complementary examination to direct the diagnosis; however only the surgery will bring a histological proof formal.  相似文献   

8.
9.
Thirty-one consecutive unconscious patients admitted to a specialist neurosurgical centre for computerised axial tomography and further management were reviewed with emphasis upon initial airway management. Fourteen patients had inadequate airway control on arrival and needed immediate intubation. Six of this group developed pulmonary complications. The implications of this are discussed and certain recommendations made.  相似文献   

10.
Primary objectives: (1) To investigate the Nonword Repetition test (NWR) as an index of sub-vocal rehearsal deficits after mild traumatic brain injury (mTBI); (2) to assess the reliability, validity and sensitivity of the NWR; and (3) to compare the NWR to more sensitive tests of verbal memory.

Research design: An independent groups design.

Methods and procedures: Study 1 administered the NWR to 46 mTBI and 61 uninjured controls with the Rapid Screen of Concussion (RSC). Study 2 compared mTBI, orthopaedic and uninjured participants on the NWR and the Hopkins Verbal Learning Test (HVLT-R).

Main outcomes and results: The NWR did not improve the diagnostic accuracy of the RSC. However, it is reliable and indexes sub-vocal rehearsal speed. These findings provide evidence that although the current form of the NWR lacks sensitivity to the impact of mTBI, the development of a more sensitive test of sub-vocal rehearsal deficits following mTBI is warranted.  相似文献   

11.
12.
The weight of the prostatic lobes in man was determined in an atuopsy series comprising 158 cases. In children the medial pair of lobes formed half of the prostate gland. The "normal" mean weights in adult men of the dorsal, lateral and medial pair of lobes were 3.6, 3.4 and 4.3 g, respectively. In adult men there was no change in lobe weight with increasing age. In subjects who died after protracted disease all of the prostatic lobes had decreased in weight. In subjects with periurethral adenomas the greater weight of the total prostate was due to higher weights of the dorsal and medial prostatic lobes. The observation that the separate prostatic lobes in man can react differently to growth promoting factors indicates that the lobation of the human prostate is not only of anatomical but also of physiological significance.  相似文献   

13.
Recent anatomical evidence from nonhuman primates indicates that cingulate motor areas (CMAs) play a substantial role in the cortical control of upper facial movement. Using event-related functional magnetic resonance imaging in 10 healthy subjects, we examined brain activity associated with volitional eye closure involving primarily the bilateral orbicularis oculi. The findings were compared with those from bimanual tapping, which should identify medial frontal areas nonsomatotopically or somatotopically related to bilateral movements. In a group-level analysis, the blinking task was associated with rostral cingulate activity more strongly than the bimanual tapping task. By contrast, the bimanual task activated the caudal cingulate zone plus supplementary motor areas. An individual-level analysis indicated that 2 foci of blinking-specific activity were situated in the cingulate or paracingulate sulcus: one close to the genu of the corpus callosum (anterior part of rostral cingulate zone) and the posterior part of rostral cingulate zone. The present data support the notion that direct cortical innervation of the facial subnuclei from the CMAs might control upper face movement in humans, as previously implied in nonhuman primates. The CMAs may contribute to the sparing of upper facial muscles after a stroke involving the lateral precentral motor regions.  相似文献   

14.
A simple method to reapply the Leksell stereotactic frame using marked carbon pins is described. This method allows the reapplication in a quick and safe manner without repetition of the CT scan. The reproducibility was very high.  相似文献   

15.
16.
We reported previously the formation of microtears in an in vivo loaded Flexor Digitorum Profundus (FDP) rabbit tendon with a repetition rate of 60 repetitions per minute and a peak force of 15% of maximum peak tetanic force for 80 cumulative hours. Tear area as a percent of tendon area, tear density (tears/mm(2)), and mean tear size (microm(2)) were higher in tendons from the loaded limb compared to the unloaded control limb. The purpose of the present study was to compare those results to results obtained with a repetition rate of 10 while maintaining the same peak force and force-time integral (n = 8). Due to a strain gradient between the inner and outer sides of the FDP tendon, microtears were quantified in four regions, two regions each along the inner and outer sides of the tendon. The tear area as a percent of total tendon area and the mean tear size were significantly greater in the loaded limb compared to the unloaded limb (p < 0.03). However, the effects were less than those observed at 60 repetitions/min. The higher repetition loading pattern resulted in an increase in tear measures in all four regions, while the lower rate produced changes only in the outer regions of the tendon. This finding may establish where the initial sites of damage occur in tendons that insert into bone in a similar arrangement as the FDP. The results suggest that repetition rate or number of loading cycles is associated with increased tendon microtears or fragility in a dose-response pattern.  相似文献   

17.
18.
The ability to locate pain plays a pivotal role in immediate defence and withdrawal behaviour. However, it is unclear to what extent nociceptive information is relayed to and processed in subcortical structures relevant for motor preparation and possibly the generation of withdrawal behaviour. We used single-trial functional magnetic resonance imaging (fMRI) to assess whether nociceptive information is represented in the putamen in a somatotopic manner. We therefore applied thulium-YAG laser-evoked pain stimuli, which had no concomitant tactile component, to the dorsum of the left hand and foot to 15 healthy subjects in a randomized order. In addition, 11 subjects were stimulated on the right body side. Differential representations of hand- and foot-related blood oxygen level dependent (BOLD) responses within the putamen were assessed using a single subject approach. Nociceptive stimuli significantly activated the putamen bilaterally. However, a somatotopic organization for hand- and foot-related responses was only present in the contralateral putamen. Here the foot was located anteriorly and medially to the hand, which parallels results from anatomical and microstimulation studies in monkeys and also human imaging data on the arrangement of movement related activity in the putamen. This result provides evidence for the hypothesis that behaviourally relevant nociceptive information without additional information from the tactile system is represented in the putamen and made available for pain related motor responses.  相似文献   

19.
Emergence of connectivity in the embryonic rat parietal cortex.   总被引:1,自引:1,他引:0  
In order to understand how cortical circuitry is put together, we examined the emergence of corticofugal projection cells and the arrival of subcortical afferents in the presumptive parietal cortex of the embryonic rat cerebrum. Afferent and efferent projections were selectively labeled by applications of the lipophilic tracers DiI and DiA in aldehyde-fixed brains of 12-18-d-old rat embryos (E12-E18; gestation: 21 d). On E12 and E13, the neocortical anlage consists of a ventricular zone and a preplate, with no extracortical connections. By E14, just prior to the appearance of the cortical plate, polymorphic cells located in the ventrolateral preplate of the telencephalic vesicle send out the first group of corticofugal axons toward the ganglionic eminence. Shortly thereafter, the cortical plate emerges as a dense band of radially oriented cells that also contribute to the corticofugal projection. By E15, axons of the early cortical projection cells cascade through the striatal primordium, the future site of the internal capsule. At the time of cortical plate formation and initial corticofugal axon outgrowth, ascending corticopetal axon systems have not yet arrived in the neocortex. Double-labeling experiments in which one dye is placed in the neocortex and the other in the ipsilateral dorsal thalamus reveal that cortical efferents encounter the first ascending wave of thalamofugal axons at the level of the striatum. Collectively, these two axonal systems bridge the necortex and the diencephalon. Upon their arrival in the neocortex on E16, thalamic axons follow a ventrolateral to dorsomedial course within the intermediate zone. Thalamic axons are the first subcortical afferent system to arrive in the neocortex. Other ascending afferent systems arising from the midbrain tegmentum enter the neocortex after E17. Comparison of thalamocortical and tegmentocortical projections in two halves of the same brain and across various embryonic ages clearly reveals that the two projection systems differ in their trajectories as well as in their time of arrival. Present observations challenge the view that the precocious arrival of subcortical axons provides the impetus for cortical maturation, and suggest that cortical plate differentiation and the initial organization of corticofugal projection patterns occur independent of ascending pathways.  相似文献   

20.
IntroductionReaders of scientific articles often read only the abstract and its conclusions because of lack of time or of access to the full-length articles.ObjectivesTo assess the prevalence of misleading conclusions in abstracts of randomized controlled trials (RCTs) in rheumatology, determine whether trials are registered and whether abstract conclusions are based on the primary outcome (PO), and identify the predictors of misleading abstract conclusions.MethodsWe searched Medline, Embase and the Cochrane Collaboration for reports of RCTs assessing rheumatoid arthritis, osteoarthritis or spondylarthropathies published between January 2006 and April 2008. Abstract conclusions were misleading if: the PO was not reported in the conclusion; the conclusions were based on only a secondary outcome or subgroup results; the results and conclusions were in disagreement; negative results were suggested as equivalent, or if there was no discussion of benefits and risks in cases of serious adverse events.ResultsOf the 144 reports selected, we focused on the 105 articles containing a clear PO. Twenty-four reports (23%) contained misleading conclusions. Lack of PO reporting (n = 10) and conclusions disagreeing with article results (n = 7) were the most frequent reasons. Nineteen out of 144 (13.2%) declared study registration with clear and similar registered and published POs and no misleading abstract conclusions. Reports of negative results showed a higher frequency of misleading conclusions as did those assessing osteoarthritis. On multivariable analysis, only negative results predicted misleading abstract conclusions (OR = 9.58 [3.20–28.70]).ConclusionsAlmost one-quarter of these RCT in rheumatology had misleading conclusions in the abstract, especially those with negative results.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号