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1.
Diffusion-weighted imaging study of patients with essential tremor.   总被引:1,自引:0,他引:1  
The pathophysiology of essential tremor (ET) is unknown. PET and fMRI studies have revealed bilateral activation and (1)H-MRS studies metabolic abnormalities in the cerebellum and other functionally related brain structures in ET. Diffusion-weighted imaging (DWI) was used to search for evidence of tissue integrity abnormalities in these areas in ET patients and 10 matched controls by calculating water apparent diffusion coefficients (ADCs). Regions of interest included the left and right cerebellum, red nucleus, thalamus, caudate, putamen, pallidum, and frontal white matter. Histograms of ADCs were generated for all pixels in the infratentorial compartment and manually segmented areas corresponding to brainstem, vermis, and cerebellar hemispheres. ADC values were similar in all brain areas in patients and controls. Our study did not detect changes affecting the investigated brain regions in ET patients. These findings argue against major structural damage in the ET brain, although more subtle neurodegenerative changes cannot be ruled out.  相似文献   
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Lodi  R.  Tonon  C.  Testa  C.  Manners  D.  Barbiroli  B. 《Neurological sciences》2006,27(2):s82-s85
Neurological Sciences - Over the last two decades magnetic resonance spectroscopy has been extensively used to investigate the role of energy metabolism impairment in the physiopathology of...  相似文献   
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BACKGROUND--Anterior chamber aspirates on completion of extracapsular cataract surgery contain significant numbers of organisms, particularly coagulase negative staphylococci, an important cause of endophthalmitis. METHODS--Culture rates were compared in 50 patients after phacoemulsification surgery, which allows the possible benefits of a small, self sealing wound and maintenance of positive intraocular pressure, with a similar number of extracapsular cases. RESULTS--A culture positive rate of 20% and 24% respectively was found, an insignificant difference. CONCLUSION--Small incision surgery has no proved advantage over extracapsular surgery in terms of reducing the intraoperative bacterial inoculum. The significance of this result in terms of causation of endophthalmitis is discussed.  相似文献   
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This brief report describes a mother and two daughters with the rare Buschke-Ollendorff syndrome. That the typical dermal connective tissue naevi lesions may become less obvious with time and that the condition is not always so "benign" are important clinical features not well recognised. Incorrect diagnosis may lead to embarkation upon hazardous management.  相似文献   
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Previous studies have suggested that human follicular fluid contains factors that reduce the zona-binding capacity of spermatozoa. The present study provides further evidence of the existence of such factors. Using the hemizona binding assay (HZA), we have shown that the inhibitory effect of human follicular fluid on the zona-binding capacity of spermatozoa is concentration-dependent, an inhibitory effect being detected when the concentration of human follicular fluid was > or = 10%. A 1% concentration of human follicular fluid did not possess this inhibitory activity. Heating human follicular fluid at 56 degrees C for 30 min did not affect its inhibitory properties; treatment with proteinase-K abolished such inhibition. Human follicular fluid was fractionated sequentially by concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography and Superose-12 gel filtration. The zona binding inhibitory activity resided in the fraction which bound to the lectin and Mono Q column and contained molecules with native molecular weights of 32 and 192 kDa. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein remained as a single molecular species under denaturing conditions. We conclude that two glycoproteins were responsible for the zona binding inhibitory activity of human follicular fluid. The physiological role of these factors remains unclear.   相似文献   
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An immunohistochemical assessment of the endometrium was carried out in a group of IVF patients on stimulated cycles, in order to evaluate this technique against standard histological methods and to consider its application in a clinical situation. Monoclonal antibodies to the two cycle-dependent proteins: pregnancy associated endometrial alpha 2-globulin (alpha 2-PEG) and 24K (a protein originally isolated from an oestrogen-dependent breast tumour line, MCF-7) were used in the experiment. Immunohistochemical results concerning the effect of drug stimulation, age and date of biopsy on the secretory state of the endometrium revealed trends which were consistent with previous histological data, helping to confirm the value of this new technique. In addition, several specimens were found to have a normal, i.e. in phase, histological appearance but to have an atypical pattern of protein secretion. These observations suggest that biochemical monitoring of the uterus should be used in conjunction with routine histological dating.  相似文献   
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Respond on comments on Lieberman's article: Cyclosiloxanes Produce Fatal Liver and Lung Damage in Mice. Environ Health Perspect 107:161-165  相似文献   
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