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121.
122.
MRI findings in Hirayama’s disease: flexion-induced cervical myelopathy or intrinsic motor neuron disease? 总被引:6,自引:0,他引:6
Schröder R Keller E Flacke S Schmidt S Pohl C Klockgether T Schlegel U 《Journal of neurology》1999,246(11):1069-1074
Hirayama’s disease is a benign juvenile form of focal amyotrophy affecting the upper limbs. Previous studies have suggested
that the disorder is a neck flexion induced cervical myelopathy. We report clinical and magnetic resonance imaging findings
in nine patients with Hirayama’s disease. Cervical imaging of seven patients revealed spinal cord changes consisting of focal
atrophy and foci of signal alterations. On neck flexion a forward movement and mild reduction in the anteroposterior diameter
of the lower cervical cord against the vertebral bodies was noted in affected individuals as well as in five normal controls.
In contrast to earlier reports, none of our patients showed complete obliteration of the posterior subarachnoid space. Measurement
of the anteroposterior spinal cord diameter in each vertebral segment (C4–C7) revealed no significant differences in the degree
of spinal cord flattening between the two groups. Furthermore, two of our patients had significant degenerative changes in
the cervical spine (disc herniation, retrospondylosis) contralateral to the clinically affected side. These degenerative changes
resulted in a marked cord compression on neck flexion but were not associated with ipsilateral clinical abnormalities or spinal
cord alterations. Our results argue against a flexion-induced cervical myelopathy and support the view that Hirayama’s disease
is an intrinsic motor neuron disease.
Received: 15 March 1999 Received in revised form: 25 May 1999 Accepted: 1 June 1999 相似文献
123.
124.
Verkoelen CF van der Boom BG Kok DJ Houtsmuller AB Visser P Schröder FH Romijn JC 《Kidney international》1999,55(4):1426-1433
BACKGROUND: Adherence of crystals to the surface of renal tubule epithelial cells is considered an important step in the development of nephrolithiasis. Previously, we demonstrated that functional monolayers formed by the renal tubule cell line, Madin-Darby canine kidney (MDCK), acquire protection against the adherence of calcium oxalate monohydrate crystals. We now examined whether this property is cell type specific. The susceptibility of the cells to crystal binding was further studied under different culture conditions. METHODS: Cell-type specificity and the influence of the growth substrate was tested by comparing calcium oxalate monohydrate crystal binding to LLC-PK1 cells and to two MDCK strains cultured on either permeable or impermeable supports. These cell lines are representative for the renal proximal tubule (LLC-PK1) and distal tubule/collecting duct (MDCK) segments of the nephron, in which crystals are expected to be absent and present, respectively. RESULTS: Whereas relatively large amounts of crystals adhered to subconfluent MDCK cultures, the level of crystal binding to confluent monolayers was reduced for both MDCK strains. On permeable supports, MDCK cells not only obtained a higher level of morphological differentiation, but also acquired a higher degree of protection than on impermeable surfaces. Crystals avidly adhered to LLC-PK1 cells, irrespective of their developmental stage or growth substrate used. CONCLUSIONS: These results show that the prevention of crystal binding is cell type specific and expressed only by differentiated MDCK cells. The anti-adherence properties acquired by MDCK cells may mirror a specific functional characteristic of its in situ equivalent, the renal distal tubule/collecting ducts. 相似文献
125.
Identification of COL4A5 defects in Alport's syndrome by immunohistochemistry of skin 总被引:11,自引:0,他引:11
van der Loop FT Monnens LA Schröder CH Lemmink HH Breuning MH Timmer ED Smeets HJ 《Kidney international》1999,55(4):1217-1224
BACKGROUND: The COL4A3-COL4A4-COL4A5 network in the glomerular basement membrane is affected in the inherited renal disorder Alport's syndrome (AS). Approximately 85% of the AS patients are expected to carry a mutation in the X-chromosomal COL4A5 gene and 15% in the autosomal COL4A3 and COL4A4 genes. The COL4A5 chain is also present in the epidermal basement membrane (EBM). It is predicted that approximately 70% of the COL4A5 mutations prevent incorporation of this chain in basement membranes. METHODS: We investigated whether or not COL4A5 defects could be detected by immunohistochemical analysis of the EBM. Punch skin biopsies were obtained from 22 patients out of 17 families and two biopsy specimens from healthy males were used as controls. RESULTS: In four cases with the COL4A5 frameshift or missense mutations, the COL4A5 chain was either lacking from the EBM (male) or showed a focally negative pattern (female). In three other patients with a COL4A5 missense mutation, a COL4A3 and a COL4A4 mutation, respectively, the COL4A5 staining was normal. A (focally) negative EBM-COL4A5 staining was found in three patients of six families with a diagnosis of AS and in one family of a group of four families with possible AS. CONCLUSIONS: The (focal) absence of COL4A5 in the EBM of skin biopsy specimens can be used for fast identification of COL4A5 defects. Combined with polymorphic COL4A5 markers, both postnatal and prenatal DNA diagnosis are possible in the family of the patient. 相似文献
126.
Rietbergen JB Hoedemaeker RF Kruger AE Kirkels WJ Schröder FH 《The Journal of urology》1999,161(4):1192-1198
PURPOSE: We describe the clinical and pathological features of prostate cancer diagnosed through serum prostate specific antigen (PSA), digital rectal examination and transrectal ultrasonography in a population based randomized screening study. MATERIALS AND METHODS: Between November 1993 and June 1997, 20,632 volunteers 55 to 76 years old were included in the study. In the screening arm 9,776 men underwent digital rectal examination, transrectal ultrasound and serum PSA determination. Biopsies were taken if the digital rectal examination and/or transrectal ultrasound findings were abnormal or if PSA was 4 ng/ml or greater. A total of 2,262 men underwent biopsy and 474 cases of prostate cancer were diagnosed. RESULTS: The pretreatment data were complete in 459 men, of whom 78% had clinically organ confined disease. Bone or lymph node metastases were seen in 8 cases (1.7%). Of 172 men who underwent radical prostatectomy 2 had lymph node metastases. Overall 66.3% of men treated with radical prostatectomy had organ confined disease. CONCLUSIONS: Comparison of the characteristics of prostate cancer detected through screening of the general population with those in a population based cohort of men in which there was no organized screening revealed stage reduction, primarily with regard to number of metastatic cases. Whether this stage reduction will lead to a decrease in disease specific mortality remains unknown until the study is completed and the end point of prostate cancer specific mortality is evaluated. 相似文献
127.
Blom JH van Poppel H Marechal JM Jacqmin D Sylvester R Schröder FH de Prijck L 《European urology》1999,36(6):570-575
OBJECTIVE: The authors present demographic and surgical data from a randomized phase III trial, instituted by the EORTC Genitourinary Group in 1988, the aim of which was to assess whether complete lymph node dissection in conjunction with radical nephrectomy for renal cell cancer is more effective than radical nephrectomy alone. METHODS: Before surgery, the renal cell carcinoma was staged and judged to be nonmetastatic and resectable. The patients were randomized prior to surgery into those having radical nephrectomy combined with complete lymph node dissection or into those having radical nephrectomy alone. Postoperatively all patients were followed until progression of disease or death. RESULTS: Of the 772 randomized patients, 41 were not eligible. 383 had a complete lymph node dissection together with a radical nephrectomy. 389 had a radical nephrectomy alone. The complication rate did not differ significantly between the two groups. A complete lymph node dissection in 336 patients revealed absence of lymph node metastases in 325 of them. CONCLUSIONS: The present study shows that complete lymph node dissection does not add morbidity to the radical nephrectomy. After proper preoperative staging, the incidence of unsuspected lymph node metastases is low (3.3%). 相似文献
128.
A novel suspension system was developed where monoglycerides were formulated together with fatty acids and subsequently admixed with antigens. In the present study, diphtheria toxoid was used as a model antigen primarily due to its weak immunological properties as well as to its importance as a future human vaccine for mucosal, particularly nasal immunization. The formulations were administered parenterally and/or nasally to mice whereafter the immune response was determined. In the present study, we have shown that mono-olein/oleic acid vesicles enhance the immunogenicity of admixed diphtheria toxoid in mice to the same level as Alum adsorbed (or Freund's complete adjuvant) when administered parenterally or nasally. It was also shown that the immunogenicity was linked to the length of the acyl chain of the lipids, where shorter acyl chains resulted in reduced titers. Furthermore, shorter acyl chains also gave rise to more pronounced toxic reactions at the injections sites, such as necrosis and alopeci, both of which were lacking when the optimal formulation consisting of mono-olein and oleic acid was used. Thus, this lipid matrix has in our view a great potential as an immunological adjuvant with an exceptionally simple and efficient preparation procedure without organic solvents and with low cost endogenous lipid based raw materials. 相似文献
129.
Schröder H 《Gesundheitswesen (Bundesverband der Arzte des Offentlichen Gesundheitsdienstes (Germany))》1999,61(11):513-517
All countries with modern industrial societies are undergoing epochal changes. These processes include globalization, internationalization and structural alterations in the work environment which have social and psychophysical consequences for the individual. These problems are rarely discussed concerning their pathogenic or health-supporting effects. Transformations of society primarily change the relationship between the demands, expectations and requirements placed on the individual and his or her abilities and competencies necessary to find solutions. This challenge simulataneously offers chances and risks for an individual's personality development, namely new demands on an individual's regulation of potential and achievement. Not only is competence in the workplace required, but social skills, emotional and self-reflective qualities are vital as well. Developing these abilities requires two tasks. One promotes and develops such skills in the individual. The second would promote sound political decisions enabling the skills in the individual to be actualized. 相似文献
130.
Dose-related effects of ethanol (placebo, 0.30, and 0.60 g/kg) on behavioral and event-related brain potential (ERP) indices
of involuntary attention shifting of audition were investigated. ERPs were recorded from 11 healthy social drinkers during
a forced-choice reaction-time (RT) task. Subjects were presented with 100 and 200 ms tones (P = 0.50 for each) with a constant inter-stimulus interval (ISI) of 1 s. The task was to press either of two buttons, depending
on the tone duration. The majority of the tones (“standards”) were of 700 Hz (P = 0.82). Occasionally, however, the frequency of the tones changed, deviating either slightly (750 Hz), moderately (900 Hz),
or widely (1200 Hz; P = 0.06 for each) from the standard frequency. In accordance with previous findings, the task-irrelevant frequency deviations
prolonged the RT. This RT prolongation was attenuated by alcohol with the 0.3 g/kg dose, thus suggesting less distraction
by irrelevant stimulus deviations under the influence of ethanol. Furthermore, the P3a, reflecting involuntary attention shifting,
was suppressed by alcohol even with the 0.3 g/kg dose. These findings demonstrate a detrimental effect of alcohol on involuntary
attention shifting, evident with doses considerably smaller than previously described, and still juridically acceptable in
road traffic in most countries.
Received: 19 December 1997/Final version: 26 May 1998 相似文献