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1.
Progressive motor syndrome in a welder with pallidal T1 hyperintensity on MRI: A two-year follow-up.
Chronic exposure to manganese (Mn) fume during welding may lead to mainly extrapyramidal syndrome that is resistant to treatment. We present a 32-year-old patient who developed severe postural instability, Parkinsonism, dystonia, and pyramidal signs in the 10th year of welding. The neurological condition of the patient worsened markedly in the following 3 years, resulting in severe disability rendering him to be assisted in all his daily activities and he did not benefit from any dopaminergic agent. T1 sequences of the MRI of the brain showed pallidal hyperintensity symmetrically. Welders in our country often protect their eyes but ignore to use tools that protect them from inhalation of the fume. Since chronic Mn toxicity may cause serious disability and irreversible neurological disturbances, we strongly believe that it is necessary to inform welders and their employers about this potential hazard. 相似文献
2.
Focal liver lesions: characterization with triphasic spiral CT 总被引:15,自引:1,他引:14
3.
Haas W Haberl B Syafruddin Idris I Kallert D Kersten S Stiegeler P;Syafruddin 《Parasitology research》2005,95(1):30-39
The infective third-stage larvae of the hookworms Necator americanus and Ancylostoma duodenale infect their human hosts by active skin invasion, but A. duodenale is in addition capable of oral infection. The behaviour of the larvae when crawling on surfaces has already been described. Here we analyse in various in vitro systems the other behavioural invasion phases: activation, penetration, and orientation within the host. The larvae normally remained in a motionless, energy-saving, resting posture. An activation to sinusoidal locomotion was stimulated in both species by similar cues such as touch, vibration, water currents, heat, light, and chemicals. Human breath in addition stimulated searching and waving (nictating) behaviour, which facilitates a change-over to the host. Activating cues in air streams were warmth and moisture; CO2 activated only in combination with warmth and/or moisture. Penetration behaviour in both species was stimulated by warmth and skin extracts. The stimulating components of skin extracts were fatty acids, but their stimulating characteristics differed from those inducing schistosome cercarial skin penetration. After penetration into agar substrates, both species showed thermo-orientation, but only A. duodenale followed gradients of serum. The directing serum cues were not amino acids and glucose (the supposed cues for schistosome blood vessel localization), but Ringers solution attracted the larvae. The host-finding and host-invasion behaviour of both hookworm species is well adapted to the invasion of the human skin, and there seems to be no particular adaptation of A. duodenale behaviour to the oral infection mode. Hookworm host-finding behaviour is not as complex as that of schistosome cercariae but seems well adapted to the ecological conditions in the transmission sites. 相似文献
4.
This paper describes a statistical image reconstruction method for x-ray CT that is based on a physical model that accounts for the polyenergetic x-ray source spectrum and the measurement nonlinearities caused by energy-dependent attenuation. Unlike our earlier work, the proposed algorithm does not require pre-segmentation of the object into the various tissue classes (e.g., bone and soft tissue) and allows mixed pixels. The attenuation coefficient of each voxel is modelled as the product of its unknown density and a weighted sum of energy-dependent mass attenuation coefficients. We formulate a penalized-likelihood function for this polyenergetic model and develop an iterative algorithm for estimating the unknown density of each voxel. Applying this method to simulated x-ray CT measurements of objects containing both bone and soft tissue yields images with significantly reduced beam hardening artefacts relative to conventional beam hardening correction methods. We also apply the method to real data acquired from a phantom containing various concentrations of potassium phosphate solution. The algorithm reconstructs an image with accurate density values for the different concentrations, demonstrating its potential for quantitative CT applications. 相似文献
5.
Abdullahi Idris Nasir Lozano Carmen Juárez-Fernández Guillermo Höfle Ursula Simón Carmen Rueda Silvia Martínez Angela Álvarez-Martínez Sandra Eguizábal Paula Martínez-Cámara Beatriz Zarazaga Myriam Torres Carmen 《European journal of clinical microbiology & infectious diseases》2023,42(5):569-581
European Journal of Clinical Microbiology & Infectious Diseases - This study determined the carriage rates and antimicrobial resistance (AMR) genes of enterococci from... 相似文献
6.
The vasa vasorum and angioplasty 总被引:2,自引:0,他引:2
Cragg AH; Einzig S; Rysavy JA; Castaneda-Zuniga WR; Borgwardt B; Amplatz K 《Radiology》1983,148(1):75-80
Interruption of flow in the vasa vasorum may lead to medial necrosis and aneurysm formation. The purpose of this study was to determine whether angioplasty produces significant alterations in the morphology or blood flow of the vasa vasorum of the dilated artery. The morphology of the canine vasa vasorum was studied before and after angioplasty; in a separate experiment vessel wall blood flow (VWBF) in canine carotid arteries was measured after angioplasty to determine whether physiologic regulation of the blood flow was disrupted by arterial dilation. No morphologic changes could be demonstrated in the vasa vasorum of the dilated artery; however, VWBF was increased by 1194 +/- 215% (mean +/- standard error, p less than 0.01) between 90 and 120 minutes after angioplasty. VWBF in the adjacent nondilated arterial segment was also increased (720 +/- 177% between 10-30 minutes, p less than 0.01) but returned toward normal after 60 minutes. Adenosine caused a "paradoxical" decrease in VWBF (p less than 0.05) of the dilated arterial segment while causing increased VWBF (p less than 0.05) in the thoracic aorta. Angioplasty appears to produce persistent hyperemia in the dilated arterial wall. A paradoxical response to adenosine suggests that vasa vasorum in the dilated arterial segment are maximally vasodilated. This may be due to mechanical disruption of vasomotor tone or to release of vasoactive substances. 相似文献
7.
WG Mitchell H Lynn JF Bale MA Maeder SM Donfield B Garg AH Tilton JK Willis TP Bohan 《Pediatrics》1997,100(5):817-824
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function. 相似文献
8.
A.M Idris S.O Ibrahim E.N Vasstrand A.C Johannessen J.R Lillehaug B Magnusson M Wallström J.-M Hirsch R Nilsen 《Oral oncology》1998,34(6):558-566
In Sweden, snuff (locally known as snus), was introduced since the year 1637. Presently, Sweden has the highest per capita consumption and sale figures of snuff in the world, and the habit is becoming increasingly popular. Snus is manufactured into a dry form used in the nasal cavity and a moist form used in the oral cavity. Snus manufactured for oral use is a moist ground tobacco of Dark Kentucky or Virginia species mixed with an aqueous solution of water and other blending ingredients. This form of snuff is found in two types: (1) loose and (2) portion-bag-packed. These are the most widely used. The loose moist form (1–2 g a quid) is the most popular type consumed by 73% of the males, followed by the portion-bag-packed form (0.5–1 g a quid), consumed by 13% of the males, while 14% of the males are mixed users. The majority of snus users place the quid in the vestibular area of the upper lip, and the prevalence among persons 15 years of age or older is 15.9% among males and 0.2% among females. The pH of snus has declined from a previous range of 8–9 to a range of 7.8–8.5, moisture content ranges 35–60% and nicotine content is in the order of 5–11 mg/g dry wt tobacco-specific N-nitrosamines (TSNAs) in micrograms (N′-nitrosonornicotine: NNN 5–9; 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone: NNK 1–2; N′-nitrosoanatabine: NAT 2–5). In the Sudan, snuff, locally known as toombak, was introduced approximately 400 years ago. It is always processed into a loose moist form, and its use is widespread in the country. Tobacco used for manufacture of toombak is of the species Nicotiana rustica, and the fermented ground powder is mixed with an aqueous solution of sodium bicarbonate. The resultant product is moist, with a strong aroma, highly addictive and its use is widespread particularly among males. Its pH range is 8–11, moisture content ranges 6–60% and nicotine content is from 8 to 102 mg/g dry wt, and TSNAs contents in micrograms (NNN 420–1 550; NNK 620–7 870; NAT 20–290). Snus and toombak dippers develop a clinically and histologically characteristic lesion at the site of dipping. Probably due to control of the TSNAs in snus, this type of snuff is associated with a lower risk of cancer of the oral cavity (relative risk: RR 5–6-fold), whereas the risk for cancer of the oral cavity among toombak users was high (RR 7.3–73.0-fold). In conclusion, the two snuff products significantly differ in many aspects. Most notable differences are tobacco species, fermentation and ageing, nicotine and TSNAs content, pH, expression of the p53 tumour supressor gene, and keratin types 13, 14, and 19. It was, therefore, the object of the present study to highlight the oral health hazards of toombak, and to compare it with snus regarding the aforementioned differences. 相似文献
9.
氯地滴眼液的含量测定 总被引:4,自引:0,他引:4
目的:采用HPLC法测定氯地滴眼液中氯霉素和地塞米松磷酸钠的含量。方法:色谱分析条件:ODS柱作分析柱,流动相为甲醇/水体系,0 ̄8min使用40%甲醇,8 ̄16min使用60%甲醇,流速1ml/min,0 ̄9min240nm紫外检测,:二组分分离良好。各组各组性关系良好,平均回收率氯霉素99.8%(RSD=1.2%,n=5),地塞米松磷酸钠99.4%(RSD=0.7%,n=5),结论:该法用于氯 相似文献
10.
Background: The association between vitamin D and weight gain remains controversial due to important limitations in the studies. We investigated the relationship between vitamin D levels and 5 and 10 years of weight and waist circumference change in a population-based prospective cohort study. Methods: Prospective study including participants aged between 35 and 75 years living in the city of Lausanne, Switzerland. Weight and waist change at 5- and 10-year follow-up were assessed according to baseline vitamin D status (normal, insufficiency and deficiency). Results: A total of 3638 participants (47.9 % women, mean age 51.6 ± 10.4 years) were included for the 5-year follow-up. No association was found between vitamin D categories and weight change, multivariate-adjusted average ± standard error: 1.6 ± 0.3, 1.5 ± 0.2 and 1.2 ± 0.1 kg for normal, insufficiency and deficiency, respectively, p = 0.159. For waist change, the corresponding values were 3.3 ± 0.4, 3.3 ± 0.2 and 3.4 ± 0.2 cm, p = 0.792. For the 10-year follow-up, data from 2999 participants (45.8% women, mean age 50.8 ± 10.3 years) were used. No association was found for weight 2.3 ± 0.4, 2.3 ± 0.2 and 2.0 ± 0.2 kg, p = 0.588, or for waist 3.7 ± 0.4, 3.6 ± 0.3 and 4.2 ± 0.2 cm for normal, insufficiency and deficiency, respectively, p = 0.259. Conclusion: No association between vitamin D status and weight or waist gain at 5- and 10-year follow-up was found. 相似文献