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41.
The wing-shape morphology of local populations of the medically important phlebotomine sand flies, Phlebotomus sergenti, P. papatasi, P. tobbi, and P. similis, were examined in both sexes by using geometric morphometrics. There are three major mountain ranges that may serve as geographical barriers for species distribution in the study area and four main gaps were recognized among these barriers. We found no statistically important differences in wing morphology in all examined species in both sexes for all local populations. These results show that the barriers are not sufficient to stop gene flow among local populations of sand flies. The graphical depiction of PCA, CVA, and F-test confirmed our morphometric study suggesting that the difference in wing morphology between P. similis and P. sergenti indicates that these are clearly different species. These two show sympatric distribution in the Konya Plain of Anatolia.  相似文献   
42.
Nasal augmentation required following a trauma or a rhinoplasty operation poses a challenging problem to many plastic surgeons. Currently, allografts and autologous tissues are used for nasal augmentation; however, an ideal technique has not yet been described. Although preferred for augmentation of different parts of the body, pure dermal graft use has not been described for nasal augmentation. The authors performed nasal augmentation using a dermal graft in 90 patients in their hospital between 1994 and 2000, and they followed up the patients for 6 months to 8 years. In this article, the early and late results of dermal grafts for nasal augmentation are presented, and their advantages and disadvantages are discussed with a review of the literature. It was concluded that the easily obtained dermal graft could be an appropriate alternative in nasal augmentation, though it has not been used widely for this purpose.  相似文献   
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The pathophysiological mechanism behind the link between antipsychotic drugs and sexual dysfunction is still unknown. The goal of this research is to compare the potential effects of antipsychotics on the male reproductive system. Fifty rats were randomly assigned into the five groups indicated: Control, Haloperidol, Risperidone, Quetiapine and Aripiprazole. Sperm parameters were significantly impaired in all antipsychotics-treated groups. Haloperidol and Risperidone significantly decreased the level of testosterone. All antipsychotics had significantly reduced inhibin B level. A significant reduction was observed in SOD activity in all antipsychotics-treated groups. While GSH levels diminished, MDA levels were rising in the Haloperidol and Risperidone groups. Also, the GSH level was significantly elevated in the Quetiapine and Aripiprazole groups. By causing oxidative stress and altering hormone levels, Haloperidol and Risperidone are damaging to male reproductivity. This study represents useful starting point for exploring further aspects of the underlying mechanisms reproductive toxicity of antipsychotics.  相似文献   
45.

Background

In high-risk coronary artery bypass patients; off-pump versus on-pump surgical strategies still remain a matter of debate, regarding which method results in a lower incidence of perioperative mortality and morbidity. We describe our experience in the treatment of high-risk coronary artery patients and compare patients assigned to on-pump and off-pump surgery.

Methods

From March 2002 to July 2004, 86 patients with EuroSCOREs > 5 underwent myocardial revascularization with or without cardiopulmonary bypass. Patients were assigned to off-pump surgery (40) or on-pump surgery (46) based on coronary anatomy coupled with the likelihood of achieving complete revascularization.

Results

Those patients undergoing off-pump surgery had significantly poorer left ventricular function than those undergoing on-pump surgery (28.6 ± 5.8% vs. 40.5 ± 7.4%, respectively, p < 0.05) and also had higher Euroscore values (7.26 ± 1.4 vs. 12.1 ± 1.8, respectively, p < 0.05). Differences between the two groups were nonsignificant with regard to number of grafts per patient, mean duration of surgery, anesthesia and operating room time, length of stay intensive care unit (ICU) and rate of postoperative atrial fibrillation

Conclusion

Utilization of off-pump coronary artery bypass graft (CABG) does not confer significant clinical advantages in all high-risk patients. This review suggest that off-pump coronary revascularization may represent an alternative approach for treatment of patients with Euroscore ≥ 10 and left ventricular function ≤ 30%.  相似文献   
46.
ST-segment elevation in Brugada syndrome is caused by a shift in the ionic current balance and the creation of a voltage gradient between the epicardium and the endocardium. This ionic mechanism have been shown to be temperature dependent. We describe a 33-year-old man who presented with fever with the dynamic electrocardiographic changes similar to the Brugada syndrome. These electrocardiographic anomalies disappeared when the temperature returned to normal.  相似文献   
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Amphiphilic, diblock copolypeptides of hydrophilic lysine or glutamic acid and hydrophobic leucine or valine have been observed to self-assemble into rigid hydrogels in aqueous solution at neutral pH and very low volume fraction of polymer, > or =0.5 wt % polypeptide. Laser scanning confocal microscopy and ultra small angle neutron scattering revealed a heterogeneous microstructure with distinct domains of hydrogel matrix and pure water pores. In situ nanoscale characterization, using cryogenic transmission electron microscopy, revealed a porous, interconnected membranous network of assembled polypeptides. At concentrations of polypeptide below gelation, diblocks containing lysine were cytotoxic to cells, whereas those containing glutamic acid were noncytotoxic. At higher polypeptide concentrations, within rigid gel scaffolds, both lysine and glutamic acid based diblocks were noncytotoxic but did not support cell attachment/proliferation. The cationic chemistry observed as cytotoxic in the fluid state was essentially inert in the intact, rigid hydrogel state.  相似文献   
49.
Senescence and quiescence are frequently used as interchangeable terms in the literature unwittingly. Despite the fact that common molecules play role in decision of cell cycle arrest, senescent and quiescent cells have some distinctive phenotypes at both molecular and morphological levels. Thus, in this review we summarized the features of senescence and quiescence with respect to visual characteristics and prominent key molecules. A PubMed research was conducted for the key words; “senescence”, “quiescence” and “cell cycle arrest”. The results which are related to cell cycle control were selected. The selection criteria of the target articles used for this review included also key cell cycle molecules such as p53, pRB, p21, p16, mTOR, p27, etc. The results were not evaluated statistically. The mechanistic target of rapamycin (mTOR) has been claimed to be key molecule in switching on/off senescence/quiescence. Specifically, although maximal p53 activation blocks mTOR and causes quiescence, partial p53 activation sustains mTOR activity and causes senescence subsequently. In broader perspective, quiescence occurs due to lack of nutrition and growth factors whereas senescence takes place due to aging and serious DNA damages. Contrary to quiescence, senescence is a degenerative process ensuing a certain cell death. We highlighted several differences between senescence and quiescence and their key molecules in this review. Whereas quiescence (cell cycle arrest) is only one half of the senescence, the other half is growth stimulation which causes actual senescence phenotype.  相似文献   
50.
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