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排序方式: 共有1498条查询结果,搜索用时 15 毫秒
1.
Targeting in a cellular level is still one of the major challenges in biomedical treatments. However, new synthetic and analytical techniques now allow the development of precisely prepared macromolecules. Thus, glycopolymer chains are reported to be prepared with controlled length, monomer sequences, as well as chain‐folded structures. A high level of complexity in synthetic macromolecules also allows increased selectivity in targeting, which is a key factor in biomedical applications. 相似文献
2.
Sema Burgaz Aysel Bayhan Ali Esat Karakaya 《International archives of occupational and environmental health》1988,60(5):347-349
Summary The excretion of thioethers was determined in the urine of workers involved in road paving operations and in the preparation of asphalt mixing in an asphalt plant. An occupationally nonexposed group served as control. From the results it was observed that there was no significant difference in urinary thioether levels between the exposed and nonexposed groups, however, smokers of both exposed groups had significantly higher urinary thioether levels than the nonexposed smoking workers. These results suggested that higher urinary thioether excretion could be only due to a difference in smoking behaviour. There were also significant differences in urinary thioether levels between the exposed smoking and nonsmoking workers. The authors suggest that these workers have a low mutagenic/carcinogenic risk and smoking is responsible for the majority of thioether excretion, as has been found by other investigators. 相似文献
3.
Lipid peroxidation, erythrocyte superoxide-dismutase activity and trace metals in young male footballers 总被引:6,自引:0,他引:6
Metin G Atukeren P Alturfan AA Gulyasar T Kaya M Gumustas MK 《Yonsei medical journal》2003,44(6):979-986
Physical training is known to induce oxidative stress in individuals subjected to intense exercise. In this study, we investigated plasma malondialdehyde (MDA) levels and erythrocyte superoxide dismutase (SOD) activity of 25 young male footballers and a control group of similar age. Red blood cell (RBC) count, haemoglobin (Hb) and haematocrit (Hct) values, and copper (Cu) and zinc (Zn) levels were also examined. The maximal oxygen uptake (VO2max) of all subjects was determined in order to establish their functional capacity. The main finding of the present study was that plasma MDA levels, one of the most commonly used markers of lipid peroxidation, of this group of footballers aged under 21 decreased slightly when compared with those of the control group (p < 0.001). In contrast, erythrocyte SOD activity was higher in the footballer group than in the controls (p < 0.001). Footballers who are under regular training showed an improved antioxidant activity in comparison to sedentary controls. Plasma copper concentration, RBC count and Hb concentration of the footballer group were all significantly lower than those of the control group, (p < 0.001, p < 0.01, p < 0.01, respectively). Investigating the footballers' data with Spearman's correlation analyses, the correlation coefficients (r) between Zn/Cu ratio and SOD was positive (r=0.44; p < 0.05); and between VO2max and SOD (r=0.42; p < 0.05) were both positive. On the basis of statistical analysis, we suggest that regular exercise may be beneficial in cases of oxidative damage by reducing the amount of lipid peroxidation and increasing the activity of the antioxidant enzyme SOD. 相似文献
4.
Mustafa Sacar Gokhan Onem Ahmet Baltalarli Suzan Sacar Huseyin Turgut Ibrahim Goksin Vefa Ozcan Serhan Sakarya 《Journal of artificial organs》2007,10(3):177-180
Because slime-forming microorganisms are the major causative agents of graft infections, we aimed to investigate bacterial
adherence in slime-forming and nonslime-forming Staphylococcus aureus and to determine the role of neuraminidase (NANase) on adherence to gelatin-impregnated polyester fiber graft fabric. An
in vitro model was developed to quantitatively measure bacterial adherence to the surface of the graft. The grafts were divided
into two groups – those colonized with slime-forming S. aureus and those colonized with nonslime-forming S. aureus. The grafts were put into sterile tubes and human plasma was instilled and incubated at 37°C to perform fibrin deposition
on the grafts. After 48 h of incubation, grafts were drained and inoculated with slime-forming or nonslime-forming S. aureus in triptic soy broth in the presence or absence of NANase. Following 36 h of incubation at 36°C, grafts were vortexed and
cultured to perform a colony count. Bacterial counts were expressed as total colony-forming units per square centimeter of
graft. Slime-forming S. aureus had greater affinity with the graft compared with nonslime-forming S. aureus (P < 0.05). The adherence of slime-forming S. aureus was impaired by NANase treatment (P < 0.001) but NANase treatment of nonslime-forming S. aureus did not change the adherence to the graft (P > 0.05). These results show that slime plays an important role in the pathogenesis of vascular graft infection. Adherence
of slime-forming S. aureus can be decreased by NANase treatment. This may have implications for the development of neuraminidase-embedded vascular grafts
to diminish biomaterial-related infections. 相似文献
5.
Yamac D Celenkoglu G Coskun U Akyurek N Akcali Z Dursun A Koybasioglu F 《Pathology, research and practice》2005,201(7):497-502
A relationship between cyclooxygenase-2 (COX-2) expression and the pathogenesis of colorectal cancer has been reported in recent studies. Moreover, it has been indicated that COX-2 expression may have a prognostic role in colorectal cancer patients. In this study, we investigated the prognostic significance of COX-2 expression in 83 patients with colorectal cancer. COX-2 expression was assessed using immunohistochemical methods and was evaluated by grading both staining intensity and staining extension. The relationships between COX-2 expression and clinicopathological features of the patients and patient survival were evaluated. There was no relationships between COX-2 expression and tumor size (tm < 3 cm or tm > or = 3 cm), tumor histopathological differentiation (poorly differentiated or moderately + well differentiated), number of metastatic lymph nodes (< 4 or 3 > or = 4), histopathology of the tumor, localization of the tumor (colon or rectum), distant metastasis, and vascular invasion of the tumor. In the multivariate analysis, COX-2 expression was not found as an independent prognostic factor. We demonstrated that COX-2 expression was not correlated with clinicopathological characteristics of colon carcinoma and disease outcome. 相似文献
6.
7.
The comparison of dual phase Tc-99m MIBI and Tc-99m MDP scintimammography in the evaluation of breast masses: Preliminary report 总被引:1,自引:1,他引:0
Arslan N Ozturk E Ilgan S Narin Y Dundar S Tufan T Pekcan M Bayhan H 《Annals of nuclear medicine》2000,14(1):39-46
The aim of this prospective study was to determine the diagnostic value of Tc-99m MDP scintimammography (SMG) for the detection of breast cancer in patients with breast masses and to compare the results with Tc-99m MIBI scintimammography. Twenty patients, categorized as suspicious, positive or benign for breast cancer according to the mammographic findings were included in the study. Dual phase Tc-99m MIBI and Tc-99m MDP SMG were performed in the prone lateral position within 5 days of each other. Although early and late Tc-99m MIBI SMG showed equal (90.4%) sensitivity, the specificity of late Tc-99m MIBI (87.5%) was found superior to early (62.5%) imaging. The overall sensitivity and specificity of early Tc-99m MDP SMG were 71.4% and 62.5%, respectively. Although late Tc-99m MDP imaging showed 100% specificity, its sensitivity was only 23.8%. In the patients with palpable masses, both early Tc-99m MDP and Tc-99m MIBI showed equal sensitivity (100%), but the sensitivity of early Tc-99m MIBI (37.5%) was found slightly higher than Tc-99m MDP (25.0%) for nonpalpable breast lesions. The sensitivity of Tc-99m MIBI and Tc-99m MDP SMG in detecting metastatic axillary involvement was 66.6% and 50%, respectively. High sensitivity and specificity together with its low cost, easy availability and the possibility of detecting bone metastases seems to make Tc-99m MDP a contributive agent in the evaluation of breast lesions as an alternative to Tc-99m MIBI. 相似文献
8.
Ugur Selek Mustafa Cengiz Gokhan Ozyigit Ferah Yildiz Ibtisam Lale Atahan 《Radiotherapy and oncology》2005,76(1):107-8; author reply 108
9.
Damien C. Weber Yucai Wang Robert Miller Salvador Villà Renata Zaucha Alessia Pica Philip Poortmans Yavuz Anacak Gokhan Ozygit Birgitta Baumert Guy Haller Matthias Preusser Jing Li 《Neuro-oncology》2015,17(4):588-595
Background
Spinal myxopapillary ependymomas (MPEs) are slowly growing ependymal gliomas with preferential manifestation in young adults. The aim of this study was to assess the outcome of patients with MPE treated with surgery, radiotherapy (RT), and/or chemotherapy.Methods
The medical records of 183 MPE patients (male: 59%) treated at the MD Anderson Cancer Center and 11 institutions from the Rare Cancer Network were retrospectively reviewed. Mean patient'' age at diagnosis was 35.5 ± 15.8 years. Ninety-seven (53.0%) patients underwent surgery without RT, and 86 (47.0%) were treated with surgery and/or RT. Median RT dose was 50.4 Gy. Median follow-up was 83.9 months.Results
Fifteen (8.2%) patients died, 7 of unrelated cause. The estimated 10-year overall survival was 92.4% (95% CI: 87.7–97.1). Treatment failure was observed in 58 (31.7%) patients. Local failure, distant spinal relapse, and brain failure were observed in 49 (26.8%), 17 (9.3%), and 11 (6.0%) patients, respectively. The estimated 10-year progression-free survival was 61.2% (95% CI: 52.8–69.6). Age (<36 vs ≥36 y), treatment modality (surgery alone vs surgery and RT), and extent of surgery were prognostic factors for local control and progression-free survival on univariate and multivariate analysis.Conclusions
In this series, treatment failure of MPE occurred in approximately one third of patients. The observed recurrence pattern of primary spinal MPE was mainly local, but a substantial number of patients failed nonlocally. Younger patients and those not treated initially with adjuvant RT or not undergoing gross total resection were significantly more likely to present with tumor recurrence/progression. 相似文献10.
Merve Osoydan Satici Mehmet Muzaffer slam Gokhan Aksel Serkan Emre Eroglu 《Malawi medical journal : the journal of Medical Association of Malawi》2022,34(3):204
Angina bullosa haemorrhgica is a relatively uncommon condition characterized by blood-filled subepithelial lesions in the oral mucosa that is idiopathic and not caused by a systemic disease or a hemostatic abnormality. Middle-aged and elderly patients are usually affected and lesions heal spontaneously without scarring. A rapidly expanding hemorrhagic blister in the oropharynx can induce upper airway obstruction, so recognizing the lesion as soon as possible is essential. Because of its rarity, we wanted to highlight a 42-year-old male patient who presented with hemorrhagic bullae associated with insignificant local trauma in the oral mucosa and to emphasize that Angina bullosa haemorrhagica is a rare but recognizable lesion that clinicians should be aware of. 相似文献