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51.
Carcinoma of unknown primary (CUP) is a heterogeneous group of tumors with various clinical features causing diagnostic and therapeutic challenges. The aim of this study was to evaluate the ability of F-18 FDG PET/CT for localizing the primary tumor, disclosing additional metastases, and changing the treatment in patients with CUP. One hundred and twelve metastatic patients (female = 40, male = 72, median age = 60.5 years) in whom conventional diagnostic work-up failed to disclose the primary tumor were included in the study. F-18 FDG PET/CT imaging was performed in a standard protocol (patient supine, arms on patient’s side, vertex to thigh, 369.3 MBq (296-444 MBq) F-18 FDG, a 60-minute uptake period, 6-7 bed position). Histopathology was taken as the only reference standard. F-18 FDG PET/CT correctly detected primary tumor in 37 of 112 (33.03%) patients. The most common site of primary tumor detected by F-18 FDG PET/CT was lung (n = 18), which was followed by nasopharynx (n = 7), pancreas (n = 5), tonsil (n = 2), breast (n = 2), thyroid (n = 1), uterus (n = 1) and colon/rectum (n = 1). F-18 FDG PET/CT imaging disclosed additional previously undetected metastases in 32 (28.5%) and changed the treatment in 33 (29.4%) of 112 patients. There were false positive F-18 FDG PET/CT results in 21 (18.5%) patients. F-18 FDG PET/CT is able to disclose the primary tumor, disclose new metatases and change the treatment in about one third of patients with CUP.  相似文献   
52.
Objective: To determine the characteristics and risk factors of drug dependence among patients who were administered drugs with addictive potential (DAP) in an emergency department (ED).Methods: This retrospective cross-sectional study included patients who were administered DAP 3 or more times in the emergency room between September 1, 2019 and March 1, 2020. The demographic and baseline information were recorded. All the prescibed DAP, the reasons to use these drugs, secondary drug dependence, the department where DAP were first prescribed, types of doctors who preferred to prescribed DAP, and the risk factors for the development of drug dependence were determined. Results: A total of 3000 patients were screened from medical records, and among them, 80 patients developed drug dependence. Drug dependence only developed for tramadol (n=57, 71.3%), diazepam (n=11, 13.8%), and biperiden (n=12, 15.0%). Tramadol was the most frequently prescribed drug (n=57, 71.3%). The most common reason for drug dependence was psychiatric disorders (n=29, 36.3%). Drug dependence developed in renal colic patients due to the administration of tramadol (n=7, 100%). On the contrary, dependence to biperiden were mainly developed in patients with psychiatric complaints (n=12, 41.4%). The rate of secondary drug dependence was 15% (n=12). Of the Biperiden users, 41.7% developed secondary drug dependence on diazepam. Most DAP were first prescribed in the ED (n=52, 65%), and the specialist preferred to prescribe DAP (n=43, 53.8%). For the development of dependence, the presence of renal colic (OR: 3.387, 95% confidence interval (CI): 1.473-7.788, P=0.004) and low back pain (OR: 5.778, 95% CI: 2.779-12.014, P<0.001) were the risk factors. Conclusions: Most DAP were first prescribed in the ED compared to other departments, and specialist are preferred to use DAP. Tramadol is the most commonly used drugs caused drug dependence. Psychiatric disorder patients are easier to develope drug dependence. Furthermore, renal colic and low back pain patients needs more attention to avert drug dependence.  相似文献   
53.
In this study, the one-step electrochemical preparation of chlorine doped and chlorine-oxygen containing functional group doped graphene-based powders was carried out by Yucel''s method, with the resultant materials used as anode materials for lithium (Li)-ion batteries. Cl atoms and ClOx (x = 2, 3 or 4) groups, confirmed by X-ray photoelectron spectroscopy analysis, were covalently doped into the graphene powder network to increase the defect density in the graphene framework and improve the electrochemical performance of Li-ion batteries. The microscopic properties of the Cl-doped graphene powder were investigated by scanning electron microscopy and transmission electron microscopy (TEM) analyses. TEM analysis showed that the one-layer thickness of the graphene was approximately 0.33 nm. Raman spectroscopy analysis was carried out to determine the defect density of the graphene structures. The G peak obtained in the Raman spectra is related to the formation of sp2 hybridized carbons in the graphene-based powders. The 2D peak seen in the spectra shows that the synthesized graphene-based powders have optically transparent structures. In addition, the number of sp2 hybridized carbon rings was calculated to be 22, 19, and 38 for the Cl-GP1, Cl-GP2, and Cl-GOP samples, respectively. As a result of the charge/discharge tests of the electrodes as anodes in Li-ion batteries, Cl-GP2 exhibits the best electrochemical performance of 493 mA h g−1 at a charge/discharge current density of 50 mA g−1.

In this study, the one-step electrochemical preparation of chlorine doped and chlorine-oxygen containing functional group doped graphene-based powders was carried out by Yucel''s method, with the resultant materials used as anode materials for lithium (Li)-ion batteries.  相似文献   
54.
Major facilitator superfamily domain-containing protein-2a (Mfsd2a) which was considered as an orphan transporter has recently gained attention for its regulatory role in the maintenance of proper functioning of the blood–brain barrier. Besides the major role of Mfsd2a in maintaining the barrier function, increasing evidence has emerged with regard to the contributions of Mfsd2a to various biological processes such as transport, cell fusion, cell cycle, inflammation and regeneration, managing tumor growth, functioning of other organs with barrier functions or responses to injury. The purpose of this article is to review the different roles of Mfsd2a and its involvement in the physiological and pathophysiological processes primarily in the central nervous system and throughout the mammalian body under the lights of the current literature.  相似文献   
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In routine parentage tests, trio analyses (father-mother-child) are preferred. Under certain circumstances, laboratories may have to perform duo analysis (without mother/father). However, duo analyses increase the risk of false inclusions. This paper aimed to evaluate the false inclusion risks of duo analyses in the Turkish population from the point of forensic applications and the Turkish judicial system. Children from 400 previously analysed cases were compared separately with fathers and mothers of other cases by using a computer programme. From the total 345,006 comparisons, in 16 comparisons, no Short Tandem Repeat (STR) mismatch was observed at 15 STR loci between the child and an unrelated parent. In other words, duo tests provided a coincidental second mother or father to 16 children. In almost all of these cases, the probabilities of paternity estimation values are greater than Turkish Judicial System’s parentage acceptance limit, which is 99.73%. According to results, we suggested that trio cases should be performed as much as possible and the parentage acceptance limit, which is 99.73%, should be re-evaluated by a law maker’s commission to prevent false inclusion parentage cases in Turkey.  相似文献   
58.
Rationale Nitric oxide (NO) is implicated in both acute effects of addictive drugs and development of dependence to them. We investigated the role of NO in nicotine-induced locomotor sensitization.Objectives The effects of N-nitro-l-arginine methyl ester (l-NAME), a NO synthase inhibitor, and a combination of a NO precursor l-arginine and l-NAME on nicotine-induced locomotor sensitization were investigated in Swiss Webster mice.Methods Sensitization to psychomotor stimulating effect of nicotine was rendered by seven injections of nicotine (1 mg/kg) on every other day. To investigate their effect on the development of sensitization to nicotine, l-NAME (15–60 mg/kg) and l-arginine (1 g/kg) were given before nicotine administration during the first seven sessions. To investigate the effect of these compounds on the expression of nicotine sensitization, after a 4-day drug-free period another group of mice received a challenge injection of nicotine on day 18.Results Nicotine (1 mg/kg) produced a robust locomotor sensitization in mice. The doses of 30 mg/kg and 60 mg/kg of l-NAME blocked the development of sensitization to nicotine; and, l-arginine (1 g/kg) pretreatment reversed this effect of l-NAME. Likewise, the doses of 30 mg/kg and 60 mg/kg of l-NAME inhibited the expression of sensitization to nicotine on day 18; and, l-arginine (1 g/kg) pretreatment reversed this inhibitory effect of l-NAME.Conclusions Our results suggest that NO is implicated in the development and expression of nicotine-induced locomotor sensitization in mice.  相似文献   
59.
Miliary tuberculosis is caused by the hematogenous spread of Mycobacterium tuberculosis and consists of 1.5% of all tuberculosis cases. It is seen mostly in infants because of the immature immune system, and central nervous system CNS involvement is not rare. Tuberculomas are rarely seen in the localized form of CNS tuberculosis, and only 4% are localized in the brain stem. We report a 4.5-month-old infant who deteriorated during follow-up with the diagnosis of cytomegalovirus pneumonia, and afterwards received the diagnosis of miliary tuberculosis. Although the baby had no neurologic abnormality and cerebrospinal fluid findings were normal, cranial MRI revealed contrast enhanced nodular lesions in pons, cerebellum, and right parietal region. The case is presented to intensify the importance of CNS investigation even if the patient with miliary tuberculosis has no neurologic finding.  相似文献   
60.
Although hyaluronic acid-carboxymethylcellulose (HA-CMC) membrane has the advantage of preventing intraabdominal adhesions, it has theoretical risk of negative effects on the healing of intestinal suture lines by forming a barrier between the suture lines and neighboring serosal surfaces. This study evaluated the effect of HA-CMC on bowel anastomoses, scar healing, and intraabdominal adhesion formation. Two groups of 10 male Sprague-Dawley rats were examined. In the first group, laparotomy was performed with a median incision. Colotomy on the cecum and a single-layer repair of the bowel wall was performed. HA-CMC membrane was placed on the cecal suture line and under the laparotomy incision before abdominal closure. The second group had the same procedure but no HA-CMC membrane was placed. The animals were killed on postoperative day 14. Intraabdominal adhesions, laparotomy suture line endurance, bursting pressure of the repaired cecal wall, and tissue hydroxyproline levels were determined. The repaired cecal wall was also examined histopathologically. The statistical analyses revealed that HA-CMC prevented intraabdominal adhesions significantly. No negative effects of this material on the healing of the bowel and laparotomy suture lines were observed. HA-CMC appears to be a safe material to prevent intraabdominal adhesions, without negative effects on the healing of abdominal incisions and bowel suture lines.  相似文献   
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