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11.
The case of a 7-year-old girl with acquired immunodeficiency syndrome treated for 5 years with AZT and intravenous gamma globulin is reported. Shortly before her demise she developed a pulmonary leiomyosarcoma and leiomyoma. Does prolonged survival in pediatric acquired immune deficiency syndrome increase the incidence of secondary malignancies?  相似文献   
12.
Central vestibular syndromes may be classified according to the three major planes of action of the vestibuloocular reflex, secondary to a lesional tone imbalance in either the horizontal yaw plane or the vertical pitch or roll plane. The clinical signs, both perceptual and motor, of a vestibular tone imbalance in the roll plane are ocular tilt reaction (OTR), ocular torsion, skew deviation and tilts of the perceived visual vertical (SVV). Either complete OTR or skew torsion without head tilt indicates a unilateral peripheral deficit of otolith input or a unilateral lesion of graviceptive brainstem pathways from the vestibular nuclei (crossing midline at the pontine level) to the interstitial nucleus of Cajal (INC) in the rostral midbrain. SVV tilts are the most sensitive sign of a vestibular tone imbalance in roll and occur with peripheral or central vestibular lesions from the labyrinth to the vestibular cortex. All tilt effects, perceptual, ocular motor and postural, are ipsiversive (ipsilateral eye undermost) with unilateral peripheral or pontomedullary lesions below the crossing of the graviceptive pathways. All tilt effects are contraversive (contralateral eye undermost) with unilateral pontomesencephalic brainstem lesions and indicate involvement of the medial longitudinal fasciculus or the rostral midbrain (INC). Unilateral lesions of vestibular structures rostral to the INC typically manifest with deviations of perceived vertical without concurrent eye–head tilt. OTR in unilateral paramedian thalamic infarctions indicates simultaneous ischemia of the paramedian rostral midbrain including the INC. Unilateral lesions of the posterolateral thalamus can cause thalamic astasia and moderate ipsiversive or contraversive SVV tilts, thereby indicating involvement of the vestibular thalamic subnuclei. Unilateral lesions of the parietoinsular vestibular cortex cause moderate, mostly contraversive SVV tilts. An SVV tilt found with monocular but not with binocular viewing is typical for a trochlear or oculomotor palsy rather than a supranuclear graviceptive brainstem lesion.  相似文献   
13.
We investigated thrombin activatable fibrinolysis inhibitor (TAFI) and its influence on fibrinolysis by measuring pro-TAFI activity and total TAFI antigen in 38 patients with type I diabetes mellitus (18 with and 20 without microvascular complications), as well as in 20 healthy controls. The pro-TAFI levels in the two groups of patients did not differ from those in the control group. Total TAFI antigen [i.e. pro-TAFI, TAFI and inactive carboxypeptidase U (TAFIi)] tended to decrease in both the patient groups (59.7 +/- 7.2 and 73.4 +/- 8.9% with and without microvascular complications, respectively) compared with controls (91.9 +/- 12.2%) (P = 0.12). We also assessed the overall hemostatic potential (OHP) in plasma, the clot lysis time and the overall fibrinolytic potential. The OHP was significantly higher in patients with complications compared with controls (8.9 +/- 0.9 versus 6.7 +/- 0.4; P < 0.05) and also higher in the diabetics without complications (7.8 +/- 0.6), although the latter difference did not reach statistical significance. Levels of clot lysis time and overall fibrinolytic potential were similar in the two groups of patients and the controls. The increased OHP in plasma from diabetic patients with microvascular complications indicates an imbalance of the hemostatic system towards a prothrombotic state. No signs of impaired fibrinolysis were observed in patients with diabetes. Using the OHP method for estimation of overall hemostasis, it seems that TAFI does not influence either fibrinolysis or the increased thrombotic potential observed in patients with type I diabetes mellitus.  相似文献   
14.
BACKGROUND AND AIMS: The aim of this work was to test the feasibility of using a bipolar low thermal acting system inducing collagenic sealing but not protein coagulation to secure hepatic parenchyma cutting. MATERIALS AND METHODS: Thirty consecutive hepatectomies were carried out using kellyclasy plus ligatures and clips (controls), while the following 50 hepatectomies used kellyclasy plus bipolar vessels sealer (BVS). Blood loss, duration of hepatic pedicle clamping, length of hospital stay, and complications were recorded. RESULTS: There was no statistically significant difference in blood loss and duration of clamping between controls and BVS. Specific complications (9/21 in the control group vs 1/49 for the BVS group, p<0.00045) and length of hospital stay (14 days in the control group vs 11 days in the BVS group, p<0.014) were statistically lower in BVS group than in the controls, mainly due to prevention of bile duct leakages. CONCLUSIONS: Our data suggest that BVS may be particularly efficient to achieve bilistasis leading to the highest level of safety in performing hepatectomies. Further studies are now needed to confirm its superiority on the classical biliary ducts occlusion techniques.  相似文献   
15.
2-[18F]Fluoro-3-(2(S)-azetidinylmethoxy)pyridine (2-[18F]F-A-85380) was among the first subtype selective radioligands to visualise the in vivo distribution of alpha4beta2-containing neuronal nicotinic acetylcholine receptors (nAChRs) in human brain. We developed a one-pot synthesis for the preparation of 2-[18F]F-A-85380 in a commercially available TRACERlab FXF-N synthesis module. The synthesis comprises a nucleophilic substitution followed by hydrolysis of a t-butyloxycarbonyl (BOC)-protected intermediate. After formulation for intravenous application up to 20 G Bq 2-[18F]F-A-85380 were produced from a starting activity of 100 G Bq [18F]fluoride in 60 min with a specific activity of about 4.10(5)GBq/mmol and a mean radiochemical purity of more than 99%.  相似文献   
16.
17.
Wilson's disease is a hereditary autosomal recessive disorder of copper metabolism. The corresponding gene locus has been localized on the long arm of chromosome 13. Three different clinical variants of the disease can be distinguished: hepato-cerebral, abdominal/hepatic, and central nervous type. The heterogeneity of symptoms can cause problems in differential diagnosis, especially when another concordant disorder can also explain the pathogenesis of symptoms. The case report of a young man who suffered from brainstem contusion demonstrates the possibilities of misinterpretation because presenting symptoms could be attributed either to traumatic brain injury followed by adjustment disorder or Wilson's disease. Clinical signs included leftsided hemiparesis, bilateral gaze direction nystagmus, marked dysarthria with consecutive pervasive mutism, choreo-athetoid movements, spasmodic torticollis and diplopia dependent on gaze direction. Slit lamp examination showed Kayser-Fleischer's corneal ring. EEG- and computer assisted tomography investigations revealed non-specific findings. The patient was treated with D-Penicillamine. Alternative treatment with oral zinc preparations is discussed.
Zusammenfassung Beim Morbus Wilson handelt es sich um eine autosomal rezessiv vererbte Störung des Kupferstoffwechsels. Der Genort konnte auf dem langen Arm des Chromosoms 13 lokalisiert werden. Klinisch können aufgrund ihrer Symptomatik drei Verlaufsformen (hepato-zerebraler, abdominalhepatischer und zerebraler Typ) unterschieden werden. Die Vielfalt der Symptome kann differentialdiagnostische Schwierigkeiten bereiten. Das Beispiel eines jungen Mannes mit einer traumatischen Hirnstammkontusion zeigt, wie die Diagnose der hepato-lentikulären Erkrankung dadurch erschwert wurde, daß die Pathogenese der Symptome durch die Hirnstammkontusion und darauf folgende Anpassungsstörungen erklärt worden war. Die Symptomatik bestand aus linksseitiger Hemiparese, lateralem Blickrichtungsnystagmus, Dysarthrie mit nachfolgendem universalem Mutismus, choreo-athetodischen Bewegungsstörungen, Torticollis spasmoidicus und blickrichtungsabhängigem Auftreten von Doppelbildern. Bei der Spaltlampenuntersuchung stellte sich der Kayser-Fleischer Ring dar. EEG- und computertomographische Untersuchungen erbrachten nur unspezifische Befunde. Die Behandlung erfolgte mit D-Penicillamin. Die alternative Behandlung mit oraler Gabe von Zinksalzen wird diskutiert.

Résumé La maladie de Wilson est une affection héréditaire autosomale recessive concernant le métabolisme cuivré. Le locus du gène a été situé sur le bras long du chromosome 13. Du point de vue clinique on distingue trois formes symptomatologiques: le type hepato-cérébral, hepato-abdominal et cérébral. La diversité des signes cliniques peut poser des problèmes de diagnostic différentiel, car d'autres affections peuvent se présenter avec cette même Symptomatologie. Nous rapportons ici l'exemple d'un homme jeune, porteur d'une maladie de Wilson et victime d'une contusion traumatique du tronc cérébral, dont les signes cliniques ainsi que les troubles du comportement pouvaient été autant rapportés à la contusion du tronc cérébral qu'à l'affection métabolique.La Symptomatologie comprenait une hemiparesie gauche, un nystagmus lateralisé, une dysarthrie avec mutisme secondaire universel, des mouvements choréo-athétosiques, un torticolis spasmodique et une diplopie dépendante de la direction du regard. L'examen à la lampe à fente permettait à mettre en evidence un anneau de Kayser Fleischer. L'EEG et le scanner cérébral ne montraient pas d'anomalies specifique.Le traitement a consisté en l'administration de D-Penicillamine. Traitment alternative avec les sels de zinc est discuté.
  相似文献   
18.
Parenting stress among caregivers of children with congenital cataracts.   总被引:1,自引:0,他引:1  
OBJECTIVE: To examine parenting stress among caregivers of young children with congenital cataracts and to assess whether diagnostic and/or treatment differences are associated with differences in perceived parenting stress. METHODS: Parents of 41 preschool-age children with congenital cataracts (13 with bilateral cataracts [BCCs] and 28 with unilateral cataracts [UCCs], of whom 14 were aphakic and 14 were pseudophakic) completed the Parenting Stress Index (PSI) and/or a disease-specific parental stress measure, ie, the Ocular Treatment Index (OTI). RESULTS: The 28-item OTI had excellent internal consistency (alpha = 0.94) and supported three of four a priori validity hypotheses. Parents of children with congenital cataracts reported normal parenting stress levels on the PSI. Parents of children with UCCs tended to report higher levels of stress, but not significantly so, than did parents of children with BCCs. Among parents of children with UCCs, those whose children were aphakic reported higher levels of stress on the OTI and all of the PSI subscales than did parents of pseudophakic children. These differences were statistically significant for two subscales (Adaptability [P =.03] and Mood [P =.01]). CONCLUSIONS: Although parents of children with congenital cataracts generally did not report increased parenting stress levels, clinicians should be aware that parenting stress can adversely impact patients' families. We did observe higher stress levels in parents with children who had UCCs and did not receive an intraocular lens-particularly stress related to their child's reaction to sensory stimulation and mood-compared with parents of pseudophakic children. Thus, clinicians may want to consider parenting stress levels when choosing a treatment for children with UCCs, especially because such stress has been associated with poor treatment compliance for children with other chronic conditions.  相似文献   
19.
PDGF AA as mediator in nicotine-dependent carcinogenesis   总被引:1,自引:0,他引:1  
Effect of nicotine on PDGF AA and PDGF BB interaction with cervicalcancer SiHa cells was tested. [125I]PDGF AA was internalizedby cells and accumulated in the cytoplasm and nucleus (chromatin).In the absence of nicotine, maximal accumulation of [125I]PDGFAA inside the cells occurred after 1 day of incubation, whichwas followed by a progressive degradation of the growth factorduring the next 2, 3 and 5 days of cell exposure. In the presenceof 0.001 or 0.01% nicotine, accumulation of [125I]PDGF AA wasslightly higher than in the absence of nicotine, and maximalaccumulation occurred after 2 days of incubation. In the presenceof 0.1% nicotine, maximal accumulation occurred after 5 daysof incubation and was 20 and 14 times higher in the cytoplasmand chromatin, respectively. Nicotine-postponed degradationand increased nuclear accumulation of PDGF AA resulted in activationof RNA synthesis and cell proliferation. PDGF BB, which wasnot internalized by cells did not respond to nicotine treatment.The proposed mechanism of nicotine-PDGF AA co-carcinogenesismay involve inhibition of growth factor degradation at the lysosomallevel and an increased chromatin accumulation of the non-degradedPDGF.  相似文献   
20.
In this retrospective study 103 serum samples from 16 females with systemic lupus erythematosus (SLE), obtained during a mean follow-up time of 2 years, were investigated for the presence of anti-denatured [single-stranded (ss)] DNA antibodies of the IgG, IgM, and IgA classes. The anti-ssDNA antibodies were determined by an enzyme-linked immunosorbent assay (ELISA), and the results were expressed in three ways: as units derived from a single serum dilution and as two parameters,E andA, calculated from the dose-response curve,E being an estimate of the effective amount of antibodies andA a function of the reaction constant between the antigen and the antibody. The simultaneous occurrence of anti-ssDNA antibodies of all three immunoglobulin classes was seen most often in the patients with the shortest duration of the disease. Clinically active disease was found to correlate with high reaction constants of the IgA anti-ssDNA antibodies. There was also an association between the IgA anti-ssDNA antibody levels and the presence of nephritis. Great fluctuations in the amounts of effective antibodies of the IgG class were seen in seven patients, in six of whom changes in the disease activity also were seen. Changes in the disease activity were unaccompanied by fluctuations in the IgG anti-ssDNA levels in four patients; two of these patients were positive for antibodies against extractable nuclear antigens. We conclude that it is of value to express the results of the anti-ssDNA ELISA as a function of the dose-response curve when monitoring patients with SLE and that immunoglobulin class-specific determinations of anti-ssDNA antibodies may provide information about the disease activity in many patients with SLE.  相似文献   
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