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11.
A wide set of biochemical and spirometrical parameters was applied to a group of 41 welders. The obtained parameters were analyzed by the pattern recognition method: principal-components analysis (PCA) and mutual contribution analysis (MCA). The aim of the investigation was to find out which of 23 parameters had an influence on the pulmonological indices of COPD. It was found that PCA gave a substantial reduction of dimensionality. The most relevant parameters were Fe, Zn, Cu (all elements in blood, not in hair), FEV1, MEF50, bilirubin, TAS, and SOD. Only the relationships of MEF50, Cu, and TAS were statistically valid.  相似文献   
12.
This paper presents results of 131I thyroid activity measurements in 30 members of the nuclear medicine personnel of the Department of Endocrinology and Nuclear Medicine Holy Cross Cancer Centre in Kielce, Poland. A whole-body spectrometer equipped with two semiconductor gamma radiation detectors served as the basic research instrument. In ten out of 30 examined staff members, the determined 131I activity was found to be above the detection limit (DL = 5 Bq of 131I in the thyroid). The measured activities ranged from (5 ± 2) Bq to (217 ± 56) Bq. The highest activities in thyroids were detected for technical and cleaning personnel, whereas the lowest values were recorded for medical doctors. Having measured the activities, an attempt has been made to estimate the corresponding annual effective doses, which were found to range from 0.02 to 0.8 mSv. The highest annual equivalent doses have been found for thyroid, ranging from 0.4 to 15.4 mSv, detected for a cleaner and a technician, respectively. The maximum estimated effective dose corresponds to 32% of the annual background dose in Poland, and to circa 4% of the annual limit for the effective dose due to occupational exposure of 20 mSv per year, which is in compliance with the value recommended by the International Commission on Radiological Protection.  相似文献   
13.
This study was performed to investigate selenoenzyme activities and trace element concentrations in thyroid tissues, with reference to other parameters routinely used to characterize thyroid function. This was to reveal relevant parameters as possible additional markers of tumor grade, clinical course, and prognosis of thyroid disorders. The tissue samples were obtained during surgical treatment (total or near total thyroidectomy) of 122 patients with different types of thyroid tumor. For most of the investigated parameters in different groups of patients, we did not find statistically significant differences. In the majority of cases, thyroid benign or malignant tumors were not accompanied by significant derangement of the gland selenoenzymes and of either intrathyroidal or plasma concentration of selenium. Nevertheless, types I and II iodothyronine deiodinases were the most promising (among selenoenzymes) targets for diagnoses and possibly therapy of thyroid tumors. Higher activities of both enzymes in cases with Graves’ disease, as compared with other thyroid lesions, suggest their involvement in the pathogenesis of this condition. Patients with struna nodosa had higher levels of thyroid Zn, Cu, and Pb as compared with papillary carcinoma subjects and also a higher level of Cu than follicular carcinoma cases. The above diagnostics may play a similar role to some of the general thyroid function indices, TSH, anti-TG, anti-TPO, and calcitonin, which can partially distinguish between various thyroid tumors. In conclusion, some of selenium status markers, when accompanied with general parameters, and trace elements can serve as factors with pathophysiologic relevance and be helpful in the identification of malignant disease. Multivariate statistical methods should be employed to tackle a broad array of thyroid tumor diagnostic data in a short time. Partial least squares model and other pattern recognition methods seem to be the most appropriate methods for that task. The miniaturization of all the steps of complex analytical procedure should be developed in a way to allow its completion as sensitive, robust, and efficient for use of the small quantity of material provided by fine-needle biopsy.  相似文献   
14.
We aimed to evaluate changes in antioxidant status in blood during valproate (VPA) monotherapy of adult patients with epilepsy. Antioxidant enzymes [plasma superoxide dismutase (pSOD), erythrocyte superoxide dismutase (eSOD)] and non-enzymatic indices [concentration of trace elements in serum: selenium, copper, zinc (sZn) and uric acid (UA), as well as the ferric reducing ability of plasma (FRAP) and UA-independent FRAP (UAiFRAP)] were evaluated in 21 adult patients with epilepsy and 21 healthy controls. Significant differences between the study group and controls were found for pSOD (p = 0.002) and UAiFRAP (p = 0.003). pSOD was higher, whilst UAiFRAP was lower in patients compared to controls. The activity of eSOD was higher in patients treated with VPA for a longer period (7–14 years) in comparison to controls (p = 0.001) and patients with a short period of VPA treatment (p < 0.001). Patients with uncontrolled epilepsy exhibited higher sZn than seizure-free patients (p = 0.041). Standard diet and moderate use of alcohol and/or nicotine did not exert significant effects on redox balance. We conclude that the antioxidant status of epileptic patients is modified by valproate monotherapy. The frequency of seizures and duration of VPA therapy are associated with changes of oxidative/antioxidative balance. The most sensitive and relevant parameters for antioxidative defence mechanism are pSOD, UAiFRAP and sZn.  相似文献   
15.
The study covered the children living in Miasteczko ?lcaskie, near the largest Zn plant in Poland. This is one of the areas highly contaminated with heavy metals. The subjects were 158 children aged from 8 to 15 (98 boys and 60 girls). The average Pb and Cd levels in the hair of the entire children population was 8.21 ± 5.59 μg/g, and 0.91 ± 0.61 μg/g, and the average Pb and Cd levels in their blood were 14.32 ± 3.98 and 0.52 ± 0.24 μg/dL-1, respectively. The children population under investigation was divided according to their sex. The hair of the girls contained, on the average, 5.06 ± 2.81 μg/g of Pb and 0.74 ± 0.48 ug/g of Cd and the hair of the boys 10.14 ± 6.0 μg/g of Pb and 1.01 ± 0.65 ug/g of Cd. The blood of the girls contained, on the average, 13.23 ± 4.23 μg/dL of Pb and 0.48 ± 0.21 μg/dL of Cd, and the blood of the boys 14.99 ± 3.68 μg/dL of Pb and 0.55 ± 0.24 μg/dL of Cd. Thus, both the hair and blood of the boys accumulated more Pb and Cd than those of the girls. A correlation between the concentrations of these metals was confirmed.  相似文献   
16.
The aim of the present work was to clarify whether the activities of selenoenzymes can serve as markers for different tumors or goiters, as classified by histological criteria. The following parameters were determined: 1) selenium content of plasma (Se), 2) activities of the selenoenzymes: plasma glutathione peroxidase (plGSHPx), cytosolic glutathione peroxidase (cGSHPx), type I and type II iodothyronine deiodinases (ID-I, ID-II), thioredoxin reductase (THRR) in human thyroid tissues. The material came from follicular neoplasm, papillary carcinoma, struma nodosa, struma lymphomatosis Hashimoto, other thyroid surgery specimens, and normal tissues. There was no difference in Se nor in plGSHPx between patients and healthy volunteers. No significant differences were found for any parameter in thyroid carcinoma versus normal or goitrous thyroid tissue. In the whole group of thyroid surgery specimens the statistically significant correlations were found between ID-I and ID-II and between THRR and selenoperoxidases. Principal components analysis confirmed the above correlation and moreover revealed correlation between Se and plGSHPx, but did not detect any clear distinction between patients with the different diagnoses.  相似文献   
17.
In this study, two ursane-type triterpenes, i. e., ursolic acid (UA) and 3-O-β-acetoxyursolic acid (AUA), were isolated and quantified in Sorbus intermedia (EHRH.) PERS. fruits. UA and AUA levels differed slightly throughout fruit maturation, and both triterpenes showed similar dynamics of accumulation with the highest levels found in ripe fruits (up to 6.33±0.56 and 1.17±0.18 mg/g dw. of UA and AUA, respectively). The extracts derived from unripe fruits displayed significant cytotoxic effects against WM793, DU-145, PC3, 8505C, Caco2 and A549 cells, but no correlation between UA and AUA levels and cytotoxicity was found. On the other hand, extracts from mature fruits were not active towards almost all of the tested cell lines. The chemometric approach showed that the extracts derived from fruits harvested earlier clustered to form a clearly distanced group from extracts prepared from more-mature fruits. The extracts at higher concentrations formed separate groups, which indicated the concentration-dependent effect of these extracts on the cells.  相似文献   
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