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41.
42.
Abstract

Background. 3-Methylmethcathinone (3-MMC) is a synthetic cathinone stimulant structurally related to the new psychoactive substance (NPS) mephedrone (4-methylmethcathinone, 4-MMC). We describe a case series of analytically confirmed intoxications involving 3-MMC presented to emergency departments in Sweden and included in the STRIDA project. Study design. Observational case series of consecutive patients with self-reported or suspected use of NPS presenting to hospitals in Sweden between August 2012 and March 2014. Methods. NPS analysis was performed by a liquid chromatography–mass spectrometry (MS)/MS method that is updated with new substances as they appear. Data on clinical features were collected during Poisons Information Centre consultations and retrieved from medical records. Results. 3-MMC was detected in 50 (6.4%) of the 786 cases included in the STRIDA project during the 20-month study period, with the peak occurring in August 2013. The age range of patients testing positive for 3-MMC was 17–49 years (median 24) and 76% of them were men. The 3-MMC concentration in serum ranged between 0.002 and 1.49 μg/mL (median, 0.091) and between 0.007 and 290 μg/mL (median, 3.05) in urine. Co-exposure to other NPS and/or traditional drugs was very common, and 3-MMC mono-intoxication was found in only 4 (8%) cases. The most frequent clinical features were tachycardia (48% of cases) and agitation (42%). Other features included a reduced level of consciousness (32%), dilated pupils (24%), hallucinations (20%), diaphoresis (12%), seizures (8%), and hyperthermia (6%). Most patients (60%) needed hospital care for only 1 day but in 8% for 3 days or longer. Conclusion. The majority of patients with analytically confirmed 3-MMC exposure had sympathomimetic features similar to those associated with mephedrone intoxication. However, the high incidence of co-exposure to other drugs makes the clinical interpretation difficult. Nevertheless, 3-MMC was associated with a high admittance rate to intensive care (30%), and detected in two cases with a fatal outcome, suggesting that 3-MMC is a harmful drug.  相似文献   
43.
《亚太生殖杂志》2014,3(3):180-183
ObjectiveTo investigate whether orally exposure to rhodamine B could be changes the expression of Bax, Bcl-2 of the hypothalamic, and also levels of Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH) in female rats.MethodsTwenty eight virgin female Wistar rats were divided into four groups, including control group, group exposed to dose of 4.5, 9 and 18 milligram/200 gram body weight (mg/200 g BW) of rhodamine B daily for 36 days. The hypothalamic expressions of Bax and Bcl-2 were examined immunohistochemically. The levels of serum FSH and LH were determined by the enzyme-linked immunosorbent assay (ELISA) technique.ResultsThe level of Bax was significantly higher in the rhodamine B treatment group compred to control group (P<0.05). Out of the 4.5, 9, and 18 mg/200 g BW doses of rhodamine B treatment, only the two highest doses significantly decreased the Bcl-2 levels compared to the control group (P<0.05). The serum FSH and LH levels were significantly lower in all dose's rhodamine B treatment groups compared with the control (P<0.05).ConclusionIn conclusion, rhodamine B increases hypothalamic cell apoptosis and disrupts hormonal balance in rats.  相似文献   
44.
目的:了解新型毒品所致精神障碍的临床特征。方法:应用自制吸毒人员一般资料调查表及简明精神病量表(BPRS)对101例新型毒品所致精神障碍患者进行调查和评定。结果:单独使用K粉或冰毒和两者混合使用3组新型毒品所致精神障碍患者的临床特征有所不同,单独使用K粉组的患者出现幻觉的比例明显高于单独使用冰毒或两者混合使用组患者(p均〈0.001),而出现妄想的比例则低于单独使用冰毒或两者混合使用组患者(p均〈0.05);BPRS评分显示,两者混合使用组患者思维障碍、激活性、敌对猜疑因子分均高于单独使用K粉或冰毒组患者(p均〈0.05)。结论:不同种类的新型毒品所致精神障碍的临床特征有所不同。  相似文献   
45.
Electrical and magnetic sensors can be lithographically fabricated on top of diamond substrates and encapsulated in a protective layer of chemical vapor deposited single crystalline diamond. This process when carried out on single crystal diamond anvils employed in high pressure research is termed as designer diamond anvil fabrication. These designer diamond anvils allow researchers to study electrical and magnetic properties of materials under extreme conditions without any possibility of damaging the sensing elements. We describe a novel method for the fabrication of designer diamond anvils with the use of maskless lithography and chemical vapor deposition in this paper. This method can be utilized to produce diamond based sensors which can function in extreme environments of high pressures, high and low temperatures, corrosive and high radiation conditions. We demonstrate applicability of these diamonds under extreme environments by performing electrical resistance measurements during superconducting transition in rare earth doped iron-based compounds under high pressures to 12 GPa and low temperatures to 10 K.  相似文献   
46.
Zirconia‐based dental restorations are becoming used more commonly. However, limited attention has been given to the difficulties experienced, concerning cutting, in removing the restorations when needed. The aim of the present study was to compare the cutting efficiency of diamond burs, operated using an electric high‐speed dental handpiece, on zirconia (Zir) with those on lithium disilicate glass–ceramic (LD) and leucite glass–ceramic (L). In addition, evaluation of the cutting efficiency of diamond burs on Zir of different thicknesses was performed. Specimens of Zir were prepared with thicknesses of 0.5, 1.0, 2.0, and 4.0 mm, and specimens of LD and L were prepared with a thickness of 1.0 mm. Cutting tests were performed using diamond burs with super coarse (SC) and coarse (C) grains. The handpiece was operated at 150,000 rpm with a cutting force of 0.9 N. The results demonstrated that cutting of Zir took about 1.5‐ and 7‐fold longer than cutting of LD and L, respectively. The SC grains showed significantly higher cutting efficiency on Zir than the C grains. However, when the thickness of Zir increased, the cutting depth was significantly decreased. As it is suggested that cutting of zirconia is time consuming, this should be taken into consideration in advance when working with zirconia restorations.  相似文献   
47.
IntroductionPerineal hernia is a protrusion of the pelvic floor containing intra-abdominal viscera. The occurrence of postoperative perineal hernia after abdominoperineal resection (APR) is rare, but reports have indicated a recent increase in occurrence following surgical treatment for rectal cancer. This has been attributed to a shift towards extralevator abdominoperineal resection, together with more frequent and long-term use of neoadjuvant therapy.Presentation of caseHere, we report the case of a patient who underwent APR for cancer. Twenty months postoperative, a perineal hernia was detected. The patient was electively scheduled for surgery. Robot-assisted laparoscopy was performed using the da Vinci Surgical System. The perineal hernia was repaired by primary closure with the placement of Symbotex Composite mesh as reinforcement for the pelvic floor. The surgery was performed without any adverse events, and the patient was discharged the day after surgery. Clinical follow-up proceeded at the designated time intervals without difficulties.DiscussionRecurrence rates of perineal hernia remain high, and surgeons face numerous challenges related to poor view, suturing and mesh placement in the deep pelvis. Numerous approaches have been described, but there is still no consensus as to the optimal repair technique for perineal hernia.ConclusionSymptomatic perineal hernias can feasibly be repaired with robot-assisted laparoscopy. Furthermore, suturing and mesh placement require less effort with the robot approach when compared to the open and laparoscopic approaches. These promising findings are demonstrated in the included video.  相似文献   
48.
运用克里斯塔勒中心地理论和引力模型等分析方法,以长江与南黄海交汇处的南通市为例,分析了以淤泥质海岸为主体江海交会处区域经济空间结构及内部差异形成的要素,以及此类地区沿海区域经济社会发展滞后的动力机制。论证了新一轮沿海开发和空间结构重构中,该类地区以沿江沿路经济轴带为基础,实施陆海统筹、江海陆协同发展的必然性。提出要充分利用原有基础,在不同区域利用各自优势,因地制宜实施发展战略,打造区域经济空间网络结构,实现区域空间均衡发展。力图从一个侧面探讨大的江河与淤泥质海岸交汇处区域发展问题的研究范式。  相似文献   
49.
The concentrations and distributions of the activity of natural radionuclides in soil samples were investigated in fifteen soil samples at El-Gor area representing two profiles (A and B) using a HP–Ge detector and alpha counting by SSNTD (CR-39), respectively. The average concentrations of the radionuclides 238U, 226Ra, 235U, 232Th and 40K are 203.4, 177.23, 9.77, 43.33 and 386.22 Bq kg−1 (dry weight), respectively, and profile A and 238U, 226Ra, 235U, 232Th and 40K have average concentrations of 232.58, 246, 11.7, 31.7, and 277.07 Bq kg−1 for profile B, respectively. The eTh and eU were estimated to detect the migration process of uranium into or out of an area or uranium to or from the studied profiles. The results indicate a migration of uranium by 29% for profile A and 65.37% for profile B. The activity ratio (238U/226Ra) was found to be 0.9 in profile A and 1.15 in profile B. These ratios coincide with the uranium migration processes. The responsible mass corresponding to the measured 226Ra activity was also calculated. The radon activity concentrations for the two profiles are nearly 300 Bq m−3. The emanation coefficient (η) was calculated from the ratio of the expected radon activity to the measured radon for the studied soil samples. The value of η was found to depend only on the radium activity regardless to soil formation.  相似文献   
50.
Among new psychoactive substances (NPS) available on the narcotic market, a significant number consists of synthetic cannabinoids commonly known as smokable herbal “spice” and “K2”, and which are legally treated as a legal alternative to marijuana. The dearth of information on the pharmacology of these intoxicants as they are introduced into the market has created the urgent need among healthcare providers for case studies on the substances belonging to this group, both in terms of the consequences of using such intoxicants, and in methods of detection. The subject of the present report is a multi-parameter analysis of a criminal case of an 18-year-old male who was charged with murder of his female relative and attempted murder of two other victims by stabbing. The defendant pleaded guilty, but he claimed that he had been acting without volition, because he was under the influence of the synthetic cannabinoid AM-2201, which had been purchased from a dealer as a 10 g package labelled “Mr Green – No bad trip”. Analytical methods including gas chromatography – electron ionization – quadrupole ion trap mass spectrometry (GC-EI-QIT/MS) and liquid chromatography, electrospray ionization, tandem mass spectrometry (LC-ESI-MS-MS) were developed to determine the presence of AM-2201 in the Mr Green – No Bad Trip, and in the blood of the perpetrator, respectively. Toxicological findings are discussed in the context of psychoactive and adverse physical effects resulting from the presence of AM-2201 in the human body; the observations were also analyzed in conjunction with data from the literature.  相似文献   
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