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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.
Medical records of 170 patients who had undergone thymectomy for myasthenia gravis were reviewed from the point of view of respiratory disturbances. In the group of patients requiring mechanical ventilation for over 24 hours after operation the incidence of high preoperative cholinesterase inhibitor intake, severe bulbar symptoms and severe myasthenia gravis with anamnestic respiratory crisis and cardiorespiratory disease were much higher than in the group of patients who could have their trachea extubation within 24 hours. The presence of a thymic tumour, patients' age over 50 years and the so-called precrisis have revealed differences between the two groups, while the patient groups were identical in mean age, duration of myasthenia gravis and sex distribution. The above clinical data are recommended to be considered in the evaluation of the need for postoperative mechanical ventilation or extubation and preparation of preventive tracheotomy.  相似文献   
3.
Ventral spondylodesis or ventrofixation is the most important surgical method for the treatment of severe cervical spine injuries accompanied by instability. Its wide indications include fracture-dislocations, compression fractures of the vertebral body, injuries to the disc, luxations, 'tear drop fractures' as well as "hangman's fractures". The essential parts of its technique: previous reduction by traction, anterior cervical approach, removal of the injured parts of vertebral body and disc(s), replacement by corticocancellous bone graft with subsequent plate-screw fixation. The authors performed in their Institute nearly 100 operations of this type, in a 10-year period of which; detailed account is given. Good results of surgery can be expected only by ensuring adequate technical conditions and professional knowledge, performing the operations in centres having sufficient experience.  相似文献   
4.
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.
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   
6.
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   
7.
Since the disialoganglioside GD2 is abundantly present on the surface of neuroblastoma cells, we constructed a new recombinant immunotoxin for possible clinical use in patients with neuroblastoma. A functional 14.18 scFv-phage was obtained by selection of an anti-GD2 hybridoma derived phage antibody mini-library on the neuroblastoma-derived, GD2-expressing cell line IMR5. By insertion into the bacterial expression vector pBM1.1 the selected scFv was fused to a deletion mutant of Pseudomonas exotoxin A (ETA'). Periplasmically expressed 14.18(scFv)-ETA' bound to the GD2 expressing cell line IMR5, but not to the GD2 negative Hodgkin-derived cell line L540Cy as documented by ELISA and flow cytometry. The recombinant immunotoxin (rIT) inhibited cell viability of IMR5 cells by 50% at concentrations (IC(50)) of 0.326 microg/ml. This recombinant immunotoxin will be further investigated in vivo for its value as a new immunotherapeutic agent for the treatment of patients with neuroblastoma.  相似文献   
8.
A modified technique for handsewn anastomosis after abdominoperineal pull-through resection is described. The technique is a continuous locked modification of the Gambee suture. Simplicity, rapidity, reliability, and firmness are the advantages of this technique.  相似文献   
9.
10.
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   
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