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Sulfonic ester is a chemical structure common to many organic molecules, including biologically active compounds. Herein, a visible-light-induced synthetic method to prepare aryl sulfonic ester from arylazo sulfones was developed. In the present study, a one-pot reaction was carried out using arylazo sulfones, DABSO (DABCO·(SO2)2), and alcohols in the presence of CuI as a coupling catalyst and HCl as an additive to yield sulfonic esters via multicomponent reaction. This synthetic method afforded a wide range of sulfonic esters with high yields under mild conditions.

Facile and efficient one-pot synthesis of sulfonic esters has been achieved via visible-light-induced multicomponent reaction of arylazo sulfones, and alcohols in the presence of DABSO, CuI, and HCI.  相似文献   
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We performed a case–control investigation to identify risk factors for norovirus infections among children in Vietnam. Of samples from 1,419 children who had diarrhea and 609 who were asymptomatic, 20.6% and 2.8%, respectively, were norovirus positive. Risk factors included residential crowding and symptomatic contacts, indicating person-to-person transmission of norovirus.  相似文献   
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建立LC-MSn法对福白菊化学成分进行定性研究,鉴定了22个化学成分,包括13个黄酮类成分和9个酚酸类成分;采用HPLC-UV法,同一色谱条件下测定福白菊中5种化学成分含量,包括:绿原酸( 1 )、木犀草素-7-O-β-D-葡萄糖苷( 2 )、木犀草素-7-O-β-D-葡萄糖醛酸苷( 3 )、3,5-二咖啡酰基奎宁酸( 4 )、芹菜素-7-O-β-D-葡萄糖苷( 5 ),建立5种化学成分的回归方程,线性关系均良好(r>0.999 9),加样回收率为98.72%~103.16%,采用此方法成功检测了10个福白菊样品中上述5种成分的含量。本文建立分析方法简便可靠,可定性及定量分析福白菊中的主要化学成分,适用于福白菊药材的质量分析。  相似文献   
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Urinary ascites is a rare diagnosis, commonly associated with bladder rupture. We present a case of intraperitoneal bladder injury following a Cesarean section with subsequent development of urinary ascites. Initial laboratory data with elevated serum creatinine and blood urea nitrogen (BUN) raised the suspicion for acute kidney injury due to the recent obstetrical procedure. This case highlights the importance of including intraperitoneal bladder injury with urinary ascites as a key differential in the workup of acute renal failure, particularly in the obstetric surgical setting. The rapid development of ascites with elevated serum BUN and creatinine should prompt work up for evaluating intraperitoneal bladder injury. Early diagnosis and treatment can yield gratifying results and avoid unnecessary workup of other causes of renal failure.  相似文献   
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OBJECTIVES: To report the utilization of a modified Endo GIA vascular stapler to obtain the full length of the renal vein during transperitoneal laparoscopic live donor right nephrectomy. METHODS: We used a modified Endo GIA stapler, in which the triple staggered rows of staples were removed from the kidney donor side to obtain the full length of the right renal vein. This technique has currently been used in nine consecutive transperitoneal laparoscopic right donor nephrectomies. RESULTS: With this technique, the entire right renal vein length was harvested in all cases, without vascular complications. Mean renal warm ischemia time from clamping of the renal vessels to cold perfusion was 135s, and mean receptor postoperative glomerular filtration rate after 30 d was 67.3 ml/min. There were no graft losses. CONCLUSIONS: A novel technique for laparoscopic live donor right nephrectomy is described. It allows harvesting the full length of the right renal vein in a safe and feasible way without compromising warm ischemia time.  相似文献   
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This prospective phase 1/2 trial investigated the safety and reproducibility of allogeneic islet transplantation (Tx) in type I diabetic (T1DM) patients and tested a strategy to achieve insulin-independence with lower islet mass. Ten C-peptide negative T1DM subjects with hypoglycemic unawareness received 1–3 intraportal allogeneic islet Tx and were followed for 15 months. Four subjects (Group 1) received the Edmonton immunosuppression regimen (daclizumab, sirolimus, tacrolimus). Six subjects (Group 2) received the University of Illinois protocol (etanercept, exenatide and the Edmonton regimen). All subjects became insulin- independent. Group 1 received a mean total number of islets (EIN) of 1460   080 ± 418   330 in 2 (n = 2) or 3 (n = 2) Tx, whereas Group 2 became insulin- independent after 1 Tx (537   495 ± 190   968 EIN, p = 0.028). All Group 1 subjects remained insulin free through the follow-up. Two Group 2 subjects resumed insulin: one after immunosuppression reduction during an infectious complication, the other with exenatide intolerance. HbA1c reached normal range in both groups (6.5 ± 0.6 at baseline to 5.6 ± 0.5 after 2–3 Tx in Group 1 vs. 7.8 ± 1.1 to 5.8 ± 0.3 after 1 Tx in Group 2). HYPO scores markedly decreased in both groups. Combined treatment of etanercept and exenatide improves islet graft function and facilitates achievement of insulin-independence with less islets .  相似文献   
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Does early repair of small abdominal aortic aneurysms (AAAs) lead to faster aneurysm sac regression or less secondary intervention? Computed tomography scans and reconstructions from M2S of all patients undergoing endovascular AAA repair at our institution from 1996 to 2006 were retrospectively reviewed. A small aneurysm is defined as an aneurysm sac to renal diameter ratio of less than 2. There were 374 patients with endovascular AAA repair that had complete imaging studies. There were 75 patients (20%) with small AAAs; of those, 19 patients (25.3%) had endoleak compared with 108 patients (36.1%) with a large aneurysm ( P = .1). Over a mean follow-up time of 42 months (range, 1-109), 11 small AAAs (14.7%) had secondary interventions compared with 58 (19.4%) of the large AAAs (P = .41). Small AAAs at 5 years had a 2.5% volume sac regression but a 3.0% increase in diameter. Those with a large aneurysm had a slight increase in sac volume and diameter at 1 month (3.3%, 1.4%) and then steadily decreased to -13.4% and -8.8% at 5 years. Patients with Endologix (Endologix Inc., Irvine, Calif) devices have the most regression when compared with patients with AneuRx (Medtronic Inc., Minneapolis, Minn) and Talent (Medtronic Inc., Minneapolis, Minn) devices. Early endovascular intervention in small AAAs does not result in faster aneurysm sac regression or secondary intervention. Aneurysm sac regression is significantly affected by endoleak, aneurysm size, and device used.  相似文献   
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