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1.
Summary The somatosensory evoked potentials (SEPs) and visual evoked potentials (VEPs) were studied in 19 patients with multiple sclerosis; 17 controls were studied during fever (38.0°–39.7°C) and 2–3 days following return to normal temperature. The latencies of components N20 and P114 were measured and specified as abnormal when their value exceeded the standard deviation of the controls by 2.5 times. The corresponding criterion for the evaluation of the amplitude of components N20 and P114 was a reduction in amplitude of more than 50%. In the controls fever did not cause significant changes in evoked potentials. On the other hand, patients with multiple sclerosis showed abnormalities in evoked potentials during fever in a greater number of recordings (26 of SEPs and 33 of VEBs) than after return to normal temperature (19 and 27 respectively). In addition, the average latency of components N20 and P114 was clearly greater in the patients during fever (N20=29.5±5.2 ms and P114=143±18.1 ms) than after return to normal temperature (N20=6.6±3.5 ms and P114=134±16 ms). The amplitude of components N20 and P114 in patients during fever was clearly smaller than after return to normal temperature. These differences were statistically significant. Finally, in two patients, a decrease was found, during fever, in the conduction velocity of the peripheral somatosensory pathway from the median nerve to the wrist at Erb's point.
Zusammenfassung Wir studierten die somatosensorisch evozierten Potentiale (SSEP) sowie die visuell evozierten Potentiale (VEP) bei 19 Patienten mit Multipler Sklerose und 17 Kontrollpersonen. Die somatosensorisch und visuell evozierten Potentiale wurden in beiden Gruppen unter dem Einfluß von Fieber als auch zwei bis drei Tage nach dem Abklingen des Fiebers untersucht.Die Latenzzeit der Komponenten N20 und P114 wurde als pathologisch bewertet, wenn ihre Werte 2,5 Standardabweichungen über dem Mittelwert von Normalpersonen lagen.Der entsprechende Maßstab für die Bewertung der Höhe der Komponenten N20 und P114 war eine Höheminderung über 50%.Wir fanden, daß Fieber bei den Kontrollpersonen keinen wesentlichen Einfluß auf SSEP und VEP hatte. Bei den MS-Patienten haben wir wesentlich mehr Abnormitäten der SSEP und VEP während des Fiebers (26 SSEP und 33 VEP) als nach dem Abklingen des Fiebers (19 SSEP und 27 VEP).Darüber hinaus war der Mittelwert der Latenzzeit der Komponenten N20 und P114 bei den MS-Patienten während des Fiebers höher (N20=29,5±5,2 ms; P114=143±18,1 ms) als nach dessen Abklingen (N20=26,6±3,5 ms; P114=134±16,8 ms).Abgesehen davon war die Höhe der Komponenten N20 und P114 während des Fiebers wesentlich kleiner als nach dem Abklingen des Fiebers.Diese Unterschiede sind statistisch signifikant.Ferner fanden wir während des Fiebers bei zwei Patienten eine Verminderung der Erregungsleitungsgeschwindigkeit im N. medianus zwischen Handgelenk und Erbschen Punkt.
  相似文献   
2.
Oxidized organic aerosol (OOA) is a major component of ambient particulate matter, substantially impacting climate, human health, and ecosystems. OOA is readily produced in the presence of sunlight, and requires days of photooxidation to reach the levels observed in the atmosphere. High concentrations of OOA are thus expected in the summer; however, our current mechanistic understanding fails to explain elevated OOA during wintertime periods of low photochemical activity that coincide with periods of intense biomass burning. As a result, atmospheric models underpredict OOA concentrations by a factor of 3 to 5. Here we show that fresh emissions from biomass burning exposed to NO2 and O3 (precursors to the NO3 radical) rapidly form OOA in the laboratory over a few hours and without any sunlight. The extent of oxidation is sensitive to relative humidity. The resulting OOA chemical composition is consistent with the observed OOA in field studies in major urban areas. Additionally, this dark chemical processing leads to significant enhancements in secondary nitrate aerosol, of which 50 to 60% is estimated to be organic. Simulations that include this understanding of dark chemical processing show that over 70% of organic aerosol from biomass burning is substantially influenced by dark oxidation. This rapid and extensive dark oxidation elevates the importance of nocturnal chemistry and biomass burning as a global source of OOA.

Highly oxidized organic aerosol (OOA) is a dominant component of particulate matter air pollution globally (13); however, sources of OOA remain uncertain, limiting the ability of models to accurately represent OOA and thus predict the associated climate, ecosystem, and health implications (4, 5). The current conceptual model of OOA formation suggests that anthropogenic OOA predominantly originates from the oxidation of volatile (VOCs), intermediate volatility (IVOCs), and semivolatile (SVOCs) organic compounds by the OH radical, resulting in lower-volatility products that condense to the particle phase (6). As the OH radical is formed through photolysis and has a very short atmospheric lifetime [less than a second (7)], this oxidation mechanism only occurs in the presence of sunlight. Further, the time scale for OOA formation through oxidation with OH in models is on the order of a few days (8). While this understanding is sufficient in explaining OOA concentrations in summer or periods with high solar radiation, atmospheric models fail to reproduce the observed concentration of OOA in the ambient atmosphere during winter and low-light conditions (9, 10). Fountoukis et al. (9) found simulated OOA concentrations significantly underestimated in wintertime Paris. Tsimpidi et al. (10) also reported an underprediction of simulated OOA globally in winter, suggesting missing sources of both primary OA (POA) and secondary formation pathways. This underproduction suggests a possible overlooked conversion pathway of organic vapors or particles to OOA that is not accounted for in current chemical transport and climate models.As stricter controls on fossil fuel combustion are implemented, residential biomass burning (BB) as a source of heating or cooking is becoming an increasingly important source of OA in urban environments (1, 11, 12). Further, increasing rates of wildfires from climate change are increasing the frequency of smoke-impacted days in urban areas (1214). BB emissions include high concentrations of POA, SVOCs, IVOCs, and VOCs (15, 16), thus making BB a key source of OOA. Previous research has focused on quantifying the concentration of OOA formed through photochemical oxidation reactions (i.e., OH) with BB emissions (17, 18). However, oxidation of BB emissions in low or no sunlight is less well understood and is not included in chemical transport models. As opposed to OH, the NO3 radical is formed through reactions with NO2 and O3 and is rapidly lost in the presence of sunlight (19). Thus, the NO3 radical is only available in significant concentrations at night or other low-light conditions (20, 21). Previous research has established that biogenic VOCs may undergo oxidation at night when mixed with anthropogenic emissions containing NO2 and O3 (19, 2227). There have been only a few studies that consider that nighttime oxidation of residential wood combustion may proceed through similar pathways (2831); however, the magnitude and relevance to observed OOA in the ambient atmosphere has not yet been established. By combining laboratory experiments and ambient observations to inform a chemical transport model, we present strong evidence that nighttime oxidation of BB plumes (proceeding through reactions with O3 and the NO3 radical) is an important source of OOA.  相似文献   
3.
4.
Next-generation mate-pair sequencing (MPS) has revealed that many constitutional complex chromosomal rearrangements (CCRs) are associated with local shattering of chromosomal regions (chromothripsis). Although MPS promises to identify the molecular basis of the abnormal phenotypes associated with many CCRs, none of the reported mate-pair sequenced complex rearrangements have been simultaneously studied with state-of-the art molecular cytogenetic techniques. Here, we studied chromothripsis-associated CCR involving chromosomes 2, 5 and 7, associated with global developmental and psychomotor delay and severe speech disorder. We identified three truncated genes: CDH12, DGKB and FOXP2, confirming the role of FOXP2 in severe speech disorder, and suggestive roles of CDH12 and/or DGKB for the global developmental and psychomotor delay. Our study confirmes the power of MPS for detecting breakpoints and truncated genes at near nucleotide resolution in chromothripsis. However, only by combining MPS data with conventional G-banding and extensive fluorescence in situ hybridizations could we delineate the precise structure of the derivative chromosomes.  相似文献   
5.
We aimed to investigate the effect of metal ions on the semen of males of child fathering age with metal-on-metal (MM) total hip arthroplasty (THA). Semen was collected form 11 patients with MM THA and 5 control of comparable age. Cobalt and chromiun concentrations were measured in both the seminal plasma and in the blood of patients. Results showed that cobalt level was higher in the seminal plasma of MM THA patients (2.89 μg/L) compared to control patients (1.12 μg/L) (P = .011). The ejaculate volume, the sperm density, the total sperm count, the pH, and the percentage of cells with normal morphology were in the range of the World Health Organization criteria for fertile population.  相似文献   
6.

Background

Subclinical Cushing syndrome in patients with adrenal incidentalomas has been associated with an increased prevalence of the metabolic syndrome and cardiovascular risk. The management of these patients, be it conservative or surgical, is still debated, but there is accumulating evidence that surgery is best and that laparoscopic adrenalectomy, when possible, is the most preferred procedure. Here we present the short- and long-term results of laparoscopic adrenalectomy for subclinical Cushing syndrome and determine the effect of this procedure on components of the metabolic syndrome.

Methods

Twenty-nine patients, 8 men and 21 women with adrenal incidentalomas and subclinical Cushing syndrome who underwent laparoscopic adrenalectomy, were studied retrospectively. They had undergone postoperative follow-up for improvement or worsening of their arterial blood pressure, body weight, and fasting glucose level for a mean period of 77 months.

Results

Preoperatively, 17 patients (58.6 %) had arterial hypertension, 14 (48.3 %) had a body mass index exceeding 27 kg/m2, and 12 (41.4 %) had diabetes mellitus. Postoperatively, a decrease in mean arterial pressure was found in 12 patients (70.6 %), a decrease in body mass index in 6 patients (42.9 %), and an improvement in glycemic control in 5 patients (41.7 %).

Conclusions

Laparoscopic adrenalectomy is beneficial in many patients with subclinical Cushing syndrome because it reduces arterial blood pressure, body weight, and fasting glucose levels. Prospective randomized studies are needed to compare laparoscopic adrenalectomy with a conservative approach and to confirm these results.  相似文献   
7.
The receptor tyrosine kinase MET and its ligand hepatocyte growth factor (HGF), have been implicated in the genesis of the paediatric tumour rhabdomyosarcoma (RMS). Addition of exogenous HGF to RH30 RMS cells enhanced non-chemotactic migration. Stable transfection of dominant negative MET into RH30 cells attenuated Matrigel invasion and in vivo tumour growth. To assess the role of a putative HGF-MET pathway in human RMS, we measured their expression in a panel of 68 human primary tumours. All tumours expressed MET but with a three orders of magnitude variation of expression and 62% of tumours co-expressed HGF. In contrast with other tumour types, neither high-MET expression nor HGF/MET coexpression correlated with metastatic disease. In a microarray screen, we identified CCN1 as being 7.8-fold up regulated following addition of HGF to RH30 cells and in RMS tumours, CCN1 expression correlated with HGF expression. Surprisingly, we identified MET as a consistent feature of embryonal and not alveolar RMS.  相似文献   
8.
European Journal of Orthopaedic Surgery & Traumatology - To evaluate the associations between magnetic resonance imaging (MRI) findings and pain, disability and quality of life before surgery...  相似文献   
9.
The administration of (131)I for the treatment of benign thyroid disease is widely used in clinical practice. The appropriate dose of (131)I, so as the gland could receive the specified absorbed dose, is determined by various methods. The mostly used is the one based on the 24 h uptake. In the present study we examined the time to measure (131)I uptake which better represents the total accumulated activity in the thyroid gland and consequently is more reliable for dose calculation. Fourteen patients, who were referred to the Nuclear Medicine Department of AHEPA University Hospital, were included in the study. 1.85 MBq of (131)I were administered and the uptake at 24, 48, 72 and 192 h was measured. From the curve of the activity vs time we calculated the area under it, which represents the total accumulated thyroid activity. We compared the uptakes of every individual with the total area and we found that the 192 h uptake was best correlated with it (r=0.996). The absorbed dose to the thyroid was calculated in the following ways: a) was based on the 24 h uptake and b) was based on the total accumulated activity on the 192 h uptake. We found differences from -19.9% to +33.7%. In conclusion, the 192 h uptake consists the most representative and reliable parameter for the estimated activity of (131)I given to the thyroid for the treatment of hyperthyroidism.  相似文献   
10.
Clinical data suggest concomitant therapy with bisphosphonates and parathyroid hormone (PTH) may blunt the anabolic effect of PTH; rodent models suggest that infrequently administered bisphosphonates may interact differently. To evaluate the effects of combination therapy with an intravenous infusion of zoledronic acid 5 mg and daily subcutaneous recombinant human (rh)PTH(1–34) (teriparatide) 20 µg versus either agent alone on bone mineral density (BMD) and bone turnover markers, we conducted a 1‐year multicenter, multinational, randomized, partial double‐blinded, controlled trial. 412 postmenopausal women with osteoporosis (mean age 65 ± 9 years) were randomized to a single infusion of zoledronic acid 5 mg plus daily subcutaneous teriparatide 20 µg (n = 137), zoledronic acid alone (n = 137), or teriparatide alone (n = 138). The primary endpoint was percentage increase in lumbar spine BMD (assessed by dual‐energy X‐ray absorptiometry [DXA]) at 52 weeks versus baseline. Secondary endpoints included change in BMD at the spine at earlier time points and at the total hip, trochanter, and femoral neck at all time points. At week 52, lumbar spine BMD had increased 7.5%, 7.0%, and 4.4% in the combination, teriparatide, and zoledronic acid groups, respectively (p < .001 for combination and teriparatide versus zoledronic acid). In the combination group, spine BMD increased more rapidly than with either agent alone (p < .001 versus both teriparatide and zoledronic acid at 13 and 26 weeks). Combination therapy increased total‐hip BMD more than teriparatide alone at all times (all p < .01) and more than zoledronic acid at 13 weeks (p < .05), with final 52‐week increments of 2.3%, 1.1%, and 2.2% in the combination, teriparatide, and zoledronic acid groups, respectively. With combination therapy, bone formation (assessed by serum N‐terminal propeptide of type I collagen [PINP]) increased from 0 to 4 weeks, declined minimally from 4 to 8 weeks, and then rose throughout the trial, with levels above baseline from 6 to 12 months. Bone resorption (assessed by serum β‐C‐telopeptide of type I collagen [β‐CTX]) was markedly reduced with combination therapy from 0 to 8 weeks (a reduction of similar magnitude to that seen with zoledronic acid alone), followed by a gradual increase after week 8, with levels remaining above baseline for the latter half of the year. Levels for both markers were significantly lower with combination therapy versus teriparatide alone (p < .002). Limitations of the study included its short duration, lack of endpoints beyond DXA‐based BMD (e.g., quantitative computed tomography and finite‐element modeling for bone strength), lack of teriparatide placebo, and insufficient power for fracture outcomes. We conclude that while teriparatide increases spine BMD more than zoledronic acid and zoledronic acid increases hip BMD more than teriparatide, combination therapy provides the largest, most rapid increments when both spine and hip sites are considered. © 2011 American Society for Bone and Mineral Research.  相似文献   
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