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81.
A kidney metastasis from a squamous bronchogenic carcinoma is described that showed the unusual feature of occupying Bowman's capsule as well as metastasizing interstitially, producing a neoplastic ;crescent' formation. The lesion is compared with the histological picture of subacute glomerulonephritis. No explanation is offered for this route for metastasis.  相似文献   
82.
OBJECTIVE: To describe clinical characteristics and lateralizing value of peri-ictal electrode manipulation automatism (EMA) in patients with temporal lobe epilepsy (TLE) and compare our data with ictal manual automatisms described in the literature. METHODS: Two-hundred and five videotaped seizures of 55 consecutive patients with refractory TLE and postoperatively seizure-free outcome were analyzed and EMA (tugging, scratching or adjusting the electrodes and cables) were monitored. RESULTS: Twenty-eight (51%) patients showed EMA during 47 (23%) seizures. Ictal start was noted in 22 seizures and in 19/22 cases EMA finished before the end of seizure. Ictal EMAs were always associated with automotor seizure components. During 25 seizures, exclusively postictal EMAs were observed. Electrode manipulation was presented during 24/112 left-sided and 23/93 right-sided seizures (p = 0.742). Peri-ictal EMA was unilateral (completed by one hand) in 24/47 seizures (10 ictal, 14 postictal); it was done by the hand ipsilateral to the seizure onset zone in 17/24 and by contralateral hand in 7/24 cases (p = 0.064). We observed concomitant contralateral dystonic posturing during 3/10 seizures with unilateral ictal EMA. Unilateral hand automatism, temporally independent from the EMA appeared in 30 (64%) of the 47 seizures. CONCLUSION: Peri-ictal EMA is a frequent phenomenon but shows no lateralizing value in TLE. The mechanism of EMA is in many ways dissimilar from that of earlier described manual automatisms.  相似文献   
83.
Objectives. Traditional deep brain stimulation (DBS) at the subthalamic nucleus (STN) has proved to be efficacious on core Parkinsonian symptoms. However, very disabling l ‐dopa–induced abnormal involuntary movements (AIMs) and axial signs are slightly affected, suggesting that we target less conventional targets. Our candidates for DBS were the globus pallidus internus (GPi) plus the intralaminar thalamic complex (Pf or CM), given its extensive functional links with basal ganglia nuclei. Materials and Methods. The routine utilization of our innovative stereotactic apparatus allows us to implant, at the same time, both the CM‐Pf complex together with the GPi in six Parkinson disease patients. Both intraoperative and postoperative neurophysiologic assessments helped us recognize functional subregions while optimizing implantation of electrodes. Unified Parkinson disease rating scale (UPDRS) motor scores, AIMs, and freezing were carefully blindly evaluated for each condition. Results. A significant amelioration of UPDRS scores was achieved by simultaneous activation of both targets. CM‐Pf activation was only slightly effective in reducing rigidity and akinesia, but more efficacious on freezing. Not surprisingly, AIMs were peculiarly decreased by the activation of the permanent electro‐catheter in the posteroventral GPi. Conclusions. These findings confirm that, in selected patients, it is conceivable to target structures other than the conventional STN in order to maximize clinical benefit.  相似文献   
84.
The concentration of brain catecholamines was measured in the hypothalamus, preoptic area (POA), frontal cortex, cerebellum, and striatum of rats exposed in utero to morphine (5–10 mg/kg/twice daily) during gestation days 11–18. Prenatal morphine induced regionally specific, sexually dimorphic alterations in male and female norepinephrine (NE), and dopamine (DA) content at different postnatal ages. Prenatal morphine significantly increased NE content in the hypothalamus of both sexes at postnatal day (PND) 23. In the POA, on the other hand, morphine increased NE content in exposed males at PND 23 and in females at PND 33. In the cerebellum, the NE content of both sexes was significantly elevated at PND 45. In the striatum, NE content was increased by the prenatal morphine only in females at PND 16. The concentration of DA was also affected in a sexually dimorphic manner. At PND 16, prenatal morphine increased the levels of hypothalamic DA only in males, and it reduced the content of DA in female but not male PDA. At PND 45, prenatal morphine increased DA in the hypothalamus of females and decreased it in males. In the cerebellum of 16-day-old morphine-exposed animals, DA levels were increased only in males; at PND 45, the levels of DA were still increased in males but had not changed in females. In the striatum, the DA content was reduced only in males at PND 16. Thus, prenatal morphine alters the development of both NE and DA neurotransmitter systems in the hypothalamus, POA, striatum, and cerebellum in a sexually dimorphic manner.  相似文献   
85.
BackgroundCholesterol 24S-hydroxylase (CYP46) catalyzes the conversion of cholesterol to 24S-hydroxycholesterol, the primary cerebral cholesterol elimination product. Only few gene variations in CYP46 gene (CYP46A1) have been investigated for their relevance as genetic risk factors of Alzheimer's disease (AD) and results are contradictory.MethodsWe performed a gene variability screening in CYP46A1 and investigated the effect of gene variants on the risk of AD and on CSF levels of cholesterol and 24S-hydroxycholesterol.ResultsTwo of the identified 16 SNPs in CYP46A1 influenced AD risk in our study (rs7157609: p = 0.016; rs4900442: p = 0.019). The interaction term of both SNPs was also associated with an increased risk of AD (p = 0.006). Haplotypes including both SNPs were calculated and haplotype G–C was identified to influence the risk of AD (p = 0.005). AD patients and non-demented controls, who were carriers of the G–C haplotype, presented with reduced CSF levels of 24S-hydroxycholesterol (p = 0.001) and cholesterol (p < 0.001).ConclusionOur results suggest that CYP46A1 gene variations might act as risk factor for AD via an influence on brain cholesterol metabolism.  相似文献   
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Visual information processing is impaired in schizophrenia patients and their biological relatives. The authors measured vernier thresholds in 72 schizophrenia patients, their 86 siblings, and 60 healthy control subjects. Subjects were asked to detect the direction of the horizontal displacement of 2 stimuli (left or right). During magnocellular (M) pathway tests, stimuli were dots with low contrast (5%) or counterphase-modulated gratings (25 Hz). For parvocellular (P) pathway tests, isoluminant blue-red dots with yellow-green background were used. Results revealed that patients with schizophrenia and their siblings were more impaired in M pathway conditions than in P pathway conditions. There was no color-specific impairment. The patients and their siblings displayed lower performances on tests of executive functions, psychomotor speed, and verbal memory compared with the controls. Visual-perceptual and neuropsychological data did not correlate. In conclusion, M pathway dysfunction is a potential endophenotype of schizophrenia.  相似文献   
89.
The method of recovering Helicobacter pylori DNA or viable cells absorbed on a string that a person has swallowed and that is retrieved an hour later (string test) should be a useful alternative to traditional analysis of cells or DNA obtained by endoscopy, which is invasive, uncomfortable, relatively costly, and ill-suited for community-based and pediatric studies. Here we assayed the sensitivity and validity of the string test versus conventional endoscopic biopsy for detecting and analyzing H. pylori infection. Forty-four people with gastric complaints were studied using both H. pylori culture and urease gene (ureB) PCR. H. pylori organisms cultured from strings and biopsy specimens from the same patients were fingerprinted by the randomly amplified polymorphic DNA (RAPD) method. Biopsy sections were also hematoxylin and eosin and silver stained for H. pylori detection. H. pylori was cultured from 80% of strings and detected by PCR from 91% of strings from participants whose biopsies had been H. pylori positive by culture, PCR, and/or histology. Strains recovered from strings and biopsy specimens yielded identical or closely related RAPD profiles in each of the 24 cases tested. We conclude that the string test is a useful method for H. pylori recovery and analysis when relatively noninvasive procedures are needed.  相似文献   
90.
OBJECTIVE: To provide health professionals involved in cervical cancer screening with an insight into the complex issues relating to communication about screening and to provide a framework for a more effective communication strategy. METHODS: This paper has been compiled by a multidisciplinary pan-European group of health professionals and cancer advocates from several European screening programmes. European surveys on screening communication, literature reviews and group discussion were used for this purpose. RESULTS: Information on cervical screening must be accessible, relevant, comprehensible, comprehensive, client-centred, phase-specific and multilevel. An effective communication strategy should consider health professionals' screening knowledge and their communication skills, consumers' health literacy skills and the communication needs of specific sub-groups in the target population. Co-operation between screening professionals, advocacy groups and journalists should be promoted. CONCLUSION: To communicate effectively and appropriately is a complex task which can be influenced by a number of factors. Screening workers need better information themselves and must take into account the needs and characteristics of the target population. PRACTICE IMPLICATIONS: This document should provide a useful tool to help screening professionals in designing and developing good quality and effective communication strategies.  相似文献   
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