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排序方式: 共有1669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.
The Arg753GLn polymorphism of the human toll-like receptor 2 gene in tuberculosis disease. 总被引:16,自引:0,他引:16
A C Ogus B Yoldas T Ozdemir A Uguz S Olcen I Keser M Coskun A Cilli O Yegin 《The European respiratory journal》2004,23(2):219-223
Toll-like receptor 2 (TLR2), a member of the Toll-like receptor family, plays an important role in recognition of, and subsequent immune response activation against, mycobacteria. The genetic polymorphism of TLR2 (arginine to glutamine substitution at residue 753 (Arg753Gln)) has been associated with a negative influence on TLR2 function, which may, in turn, determine the innate host response to mycobacteria. The aim of the present study was to investigate the Arg753Gln single nucleotide polymorphism of the TLR2 gene in tuberculosis (TB) patients compared to healthy controls. A retrospective case/control study was carried out. The Arg753Gln polymorphism of the TLR2 gene was studied in 151 TB patients compared to 116 ethnically and age-matched healthy control subjects. The TLR2 polymorphism (adenine (A) allele) was observed in 17.9 and 7.7% of TB patients and controls, respectively. When the ratios of the three genotypes were compared between the two groups, the AA genotype was found to be more significantly associated with TB. Allele frequencies for guanine (G) and A were found to be 0.95 and 0.05 in the control group and 0.86 and 0.14 in the TB patient group, respectively. The risk of developing TB disease was increased 6.04- and 1.60-fold for carriers of the AA and GA genotypes, respectively. In conclusion, the present data suggest that the arginine to glutamine substitution at residue 753 polymorphism of the Toll-like receptor 2 gene influences the risk of developing tuberculosis. 相似文献
3.
Abdülmuttalip Keser Murat Bozkurt Omer Faruk Taner Mithat Akan Omer Sens?z 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2004,38(5):257-260
The various methods of prefabricating flaps include vascular induction through staged transfer; pretransfer delay, expansion, and grafting; the use of alloplastic materials; and tissue bioengineering. In this experimental study, vascular induction was used to provide an axial vascular pedicle to randomly nourished tissue. Twenty-six New Zealand rabbits, ages and weights ranging between 6 months-1 year and 1.5-3.5 kg, respectively, were used. The sex difference was not considered. The deep inferior epigastric artery and vein were used to carry blood and were placed into a segment of femur to prefabricate the bone. Four weeks later, the viability of the segment of bone prefabricated by new axial pedicle was shown by scintigraphic study, and the new axial pedicle was ready for free transfer. 相似文献
4.
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
5.
Ahter Dilsad Toraman Ibrahim Keser Güven Lüleci Nurdan Tunali Tekinalp Gelen 《Cancer Genetics and Cytogenetics》2002,132(1):36-40
The ganglioneuroblastoma are rare lesions with widespread neuronal differentiation that have been classified as intermediate stages between neuroblastoma and ganglioneuroma. To identify overall chromosome aberrations in ganglioneuroblastoma, we performed comparative genomic hybridization. All of the five tumor samples were found to exhibit multiple gains involving different chromosomal regions. Chromosomal gains displayed by chromosomes and chromosome loci were 2p25 approximately pter (60%), 5p15.1 approximately p15.3 (60%), 7 (60%), 13q22 approximately q31 (60%), and 22 (60%), which were detected as minimal common regions in all five tumor samples. Chromosome 22 gain, which had not been reported in neuronal tumors before, and novel site 13q22 approximately q31 may be considered to play an important role in progression and differentiation of ganglioneuroblastoma. 相似文献
6.
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
7.
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
8.
Ugur Selek Mustafa Cengiz Gokhan Ozyigit Ferah Yildiz Ibtisam Lale Atahan 《Radiotherapy and oncology》2005,76(1):107-8; author reply 108
9.
Suleyman Ercan M.D. Gokhan Gokaslan M.D. Vedat Davutoglu M.D. Ibrahim Halil Inanc M.D. Vuslat Bosnak M.D. Hayati Deniz M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(8):E236-E238
Herein, we present a case of asymptomatic isolated cardiac cystic echinococcosis localized entirely to the inter‐atrial septum in a pregnant woman. The patient underwent successful surgery. Cardiac cystic echinococcosis is rarely seen in pregnancy. A high index of suspicion is necessary for the diagnosis of a cardiac cyst hydatid. The treatment of cardiac cyst hydatid is surgical and should not be delayed during pregnancy. Early surgery might prevent septic embolization and cardiac life‐threatening complications and save the lives of both mother and baby as in the present case. 相似文献
10.