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1.
Baki Hazer Alipaa Ayas Necati Beirli Necdet Saltek Bahattin M. Baysal 《Macromolecular chemistry and physics.》1989,190(8):1987-1996
Some new macroinitiators ( 5 ) containing azo and peroxy groups were synthesized by transformation of esters of poly(ethylene glycol) ( 1 ) (PEG) of different molecular weight with hydroxyl end groups and an azo group in the middle into the corresponding polymers with tert-butylperoxycarbonyl end groups by reaction with terephthaloyl chloride and subsequently with tert-butyl hydroporoxide. Decomposition in the presence of styrene at 60°C or with 3,6,9-triazaun-decane-1,11-diamine in presence of methyl methacrylate gave the corresponding ABA block copolymer 6 and the ABBA block copolymer 7 , respectively. Both block copolymers were used as polymeric initiators. The ABCBA block copolymer 8 was synthesized from 6 and methyl methacrylate or from 7 and styrene by thermally induced polymerization at 80°C. The resulting block copolymers were separated from the homopolymers by selective solvent extraction and characterized by spectroscopic and fractional precipitation methods. 相似文献
2.
Virus-like particles were found in the brain and salivary glands of Dermacentor reticulatus ticks double infected with Coxiella burnetii and Rickettsiella phytoseiuli. The particles were spherical (diameter of about 70 nm) and consisted of an electron-dense inner core and a dense external coat. 相似文献
3.
Biochemical profile of blood serum of siraz <Emphasis Type="Italic">Capoeta capoeta umbla</Emphasis>
Abdulkadir Bayir A. Necdet Sirkecioğlu Harun Polat N. Mevlüt Aras 《Comparative clinical pathology》2007,16(2):119-126
Seasonal changes in blood plasma biochemistry of siraz Capoeta capoeta umbla were determined throughout 1 year. In the present study, while the highest values for glucose and globulin were found in
winter, the values for increased activities of total protein, albumin, calcium, sodium levels, albumin/globulin ratio, lactate
dehydrogenase, and alkaline phosphatase were determined in summer. We determined that blood biochemistry values of siraz,
which were positively affected by water temperature and pH, except glucose and globulin. Glucose and globulin were negatively
affected by water temperature and pH. Consequently, it was concluded that the seasons are key factors when blood parameters
are used as biomarkers for environmental alterations. It is difficult to define the most important factors affecting seasonal
changes of blood biochemistry in fish. 相似文献
4.
Sönmez AS Yasar L Savan K Koç S Ozcan J Toklar A Yazicioğu F Akgün A Sut N 《Human reproduction (Oxford, England)》2005,20(1):175-179
BACKGROUND: The aim of this study was to evaluate the effects of metformin and acarbose on insulin resistance, hormone profiles and ovulation rates in patients with clomiphene citrate-resistant polycystic ovary syndrome (PCOS). METHODS: Thirty clomiphene citrate-resistant patients were selected randomly and divided into two groups. Group I was treated with 100 mg/day clomiphene citrate and 300 mg/day acarbose 100 mg/day orally, for 3 months. Group II was treated with clomiphene citrate 100 mg/day and metformin 1700 mg/day orally, for 3 months. Serum fasting insulin and glucose, FSH, LH, estradiol, progesterone, prolactin and total testosterone levels plus body mass index (BMI) were measured before and after treatment. Follicle growth was followed by transvaginal ultrasonography. RESULTS: LH:FSH ratio and total testosterone concentrations decreased (P<0.05) and ovulation rates increased in both groups. Reduction in weight and BMI was only significant in the acarbose group. CONCLUSIONS: Both treatment modalities were effective in the treatment of insulin resistance and improving ovulation rates. Increase in the number of eumenorrhoeic and normoinsulinaemic cases and decrease in the number of insulin-resistant cases were significant in both groups (P<0.05). Ovulation rate was greater in the metformin group in the second month of therapy (P<0.05). Acarbose was found to be a safe and effective agent that could be used in cases with clomiphene-resistant PCOS. 相似文献
5.
Charlie Dharmasukrit Sut Yee Shirley Chan Richard L. Applegate Daniel J. Tancredi Theresa A. Harvath Jill G. Joseph 《The Journal of arthroplasty》2021,36(6):1895-1903
BackgroundAlthough frailty has been shown to be associated with adverse outcomes in patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA), prior studies have not examined how race/ethnicity might moderate these associations. We aimed to assess race/ethnicity as a potential moderator of the associations of frailty and functional status with arthroplasty outcomes.MethodsThe National Surgical Quality Improvement Program was queried for patients who underwent THA or TKA from 2011 to 2017. Frailty was assessed using the modified frailty index. Regression analyses were conducted to examine associations connecting frailty/functional status with 30-day readmission, adverse discharge, and length of stay (LOS). Further analyses were conducted to investigate race/ethnicity as a potential moderator of these relationships.ResultsWe identified 219,143 TKA and 130,022 THA patients. Frailty and nonindependent functional status were positively associated with all outcomes (P < .001). Compared to White non-Hispanic patients, Black non-Hispanic patients had higher odds for all outcomes after TKA (P < .001) and for adverse discharge/longer LOS after THA (P < .001). Similar associations were observed for Hispanics for the adverse discharge/LOS outcomes. Race/ethnicity moderated the effects of frailty in TKA for all outcomes and in THA for adverse discharge/LOS. Race/ethnicity moderated the effects of nonindependent function in TKA for adverse discharge/LOS and on LOS alone for THA.ConclusionDisparities for Black non-Hispanic and Hispanic patients persist for readmission, adverse discharge, and LOS. However, the effects of increasing frailty and nonindependent functional status on these outcomes were the most pronounced among White non-Hispanic patients. 相似文献
6.
Murat Yilmaz Orhan Kalemci Hakan Yilmaz Necdet M. Palaz 《International journal of surgery case reports》2013,4(8):645-647
INTRODUCTIONSymtomatic lumbar ligamantum flavum calcification is quite rare in the young age group.PRESENTATION OF CASEThe authors report a case of young adult with diagnosis of lumbar spinal stenosis, presenting with leg pain and neurological deficits. Computerized tomography (CT) scan and magnetic resonance (MR) imaging studies revealed ossification of the ligamantum flavum as the causative factor of the disease and the patient recovered completely after the decompressive operation.DISCUSSIONIt is emphasized that attention should be given to this rare etiological factor of lumbar spinal stenosis.CONCLUSIONComplete relief can be achieved with early and adequate surgery. 相似文献
7.
Aylin Yaba Umit Kayisli Gamze Tanriover Necdet Demir 《International journal of developmental neuroscience》2011,29(2):131-136
Vasodilator-stimulated phosphoprotein (VASP) is a member of the Ena/VASP protein family and was for the first time identified in human platelets. VASP plays a role for cell adhesion and cell migration because of E/DFPPPPXD/E amino acid sequence in its structure which gives reaction with focal adhesion proteins. In this study we suggest that VASP expression may have important role for neural cell migration, differentiation, axonal growth and angiogenesis during prenatal cerebral cortical development. Our aim is to detect VASP expression by means of immunohistochemistry and Western blot analysis in developing human neocortex and adult brain cortex (n = 12 samples from first, second, and third trimesters and n = 3 adult normal cerebral cortex). Our results suggest that VASP showed different immunostaining patterns between cerebral cortical plates in prenatal and adult human brain samples. We observed that the expression patterns of the VASP protein are clearly identified in fibers, cytoplasm of neural cells and endothelial cells of vessels. We detected that VASP indicates progressive expression from the adult brain to second trimester neocortexes. Therefore, we suggest that VASP may play a crucial role in the regulation of human neonatal cerebral cortical development. 相似文献
8.
9.
Gamze Tanriover Berna SozenMurat Gunel Necdet Demir 《International journal of developmental neuroscience》2011,29(5):509-514
Cerebral cavernous malformation (CCM) is one of the most common types of vascular malformations of the central nervous system, affecting nearly one in 200 people. CCM lesions are characterized by grossly dilated vascular channels lined by a single layer of endothelium. Genetic linkage analyses have mapped three CCM loci to CCM1, CCM2 and CCM3. All three causative genes have now been identified allowing new insights into CCM pathophysiology. We focused on the CCM2 protein that might take place in blood vessel formation; we report here the expression patterns of CCM2 in prenatal development and adult human neocortex by means of immunohistochemistry and Western blot analysis. CCM2 was obviously detected in vascular endothelium and neuroglial precursor cells during development and also observed in arterial endothelium, neurons, some of the glial cells in adult neocortex. The expression patterns suggest that it could be one of the arterial markers whether this is a cause or a consequence of an altered vascular identity. CCM2 might play a role during vasculogenesis and angiogenesis during human brain development. Furthermore, with this study, CCM2 have been described for the first time in developing human neocortex. 相似文献
10.
Mehmet Cihan Cakir Hasan Kocer Yilmaz Durna Deniz Umut Yildirim Amir Ghobadi Hodjat Hajian Koray Aydin Hamza Kurt Necdet Saglam Ekmel Ozbay 《RSC advances》2020,10(50):29945
The phase change behavior of vanadium dioxide (VO2) has been widely explored in a variety of optical and photonic applications. Commonly, its optical parameters have been studied in two extreme regimes: hot (metallic) and cold (insulating) states. However, in the transition temperatures, VO2 acts like an inherent metamaterial with mixed metallic-insulating character. In this range, the portions of metallic and insulating inclusions are tuned by temperature, and therefore a gradual change of optical parameters can be achieved. In this paper, a universal hybrid modeling approach is developed to model VO2 in the intermediate region. For this aim, the measured reflectivity data, is analyzed and matched through the transfer matrix method (TMM) simulations where an effective medium theory (EMT) is employed. Based on the findings of this approach, not only the relative portions of inclusions are tailored but also their grain shapes are significantly altered in the transition range. Finally, the modeling approach is testified by experimental findings through dynamic device applications operating at short and mid infrared wavelengths. In addition, the hysteretic behaviors on electrical, optical, and structural parameters of the VO2 film along the heating and cooling cycles are demonstrated by the experiments and scrutinized by the simulations.A universal hybrid modeling approach is developed to model VO2 in transition, revealing dynamic behavior of metallic inclusions and grain shapes. 相似文献