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91.
Sandeep Chaudhary Bharti Rajesh K. Shyamlal Lalit Yadav Mohit K. Tiwari Krishan Kumar 《RSC advances》2018,8(41):23152
Herein, we disclose the first example of an efficient, silver oxide nanoparticle-catalyzed, direct regioselective synthesis of 3-ylidenephthalides 11–16 and isocoumarins 17–20via sonogashira type coupling followed by substrate-controlled 5-exo-dig or 6-endo-dig cyclization reaction, respectively. This one pot coupling involves reaction of substituted 2-halobenzoic acid with meta/para-substituted and ortho-substituted terminal alkynes, which proceeded in a regioselective manner resulting in the formation of 3-ylidenephthalides or isocoumarins, respectively, in excellent yields (up to 95%) with complete Z-selectivity. This protocol features relatively broad substrate scope, mild conditions, operational simplicity, and is favourable with aromatic/alicyclic terminal alkynes. The competition experiments and gram-scale synthesis further highlight the importance and versatility of the methodology. The proposed mechanistic pathways illustrate that the regioselectivity is substantially being controlled by the substituent(s) present on the acetylenic phenyl ring.We report the first example of an efficient, Ag2O nanoparticle-catalyzed, direct regioselective synthesis of 3-ylidenephthalides and isocoumarins via Sonogashira type coupling followed by substrate-controlled 5-exo-dig or 6-endo-dig cyclization reaction, respectively. 相似文献
92.
Synthesis and Evaluation of New 4‐Chloro‐2‐(3‐chloro‐4‐fluorophenyl)‐5‐(aliphatic/cyclic saturated amino)pyridazin‐3(2H)‐one Derivatives as Anticancer,Antiangiogenic, and Antioxidant Agents
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93.
Moon JC De Arenaza DP Elkington AG Taneja AK John AS Wang D Janardhanan R Senior R Lahiri A Poole-Wilson PA Pennell DJ 《Journal of the American College of Cardiology》2004,44(3):554-560
OBJECTIVES: The purpose of this study was to determine the pathologic basis of Q-wave (QW) and non-Q-wave (NQW) myocardial infarction (MI). BACKGROUND: The QW/NQW distinction remains in wide clinical use but the meaning of the difference remains controversial. We hypothesized that measurement of total MI size and transmural extent by late gadolinium enhancement cardiovascular magnetic resonance (CMR) would identify the pathologic basis of QWs. METHODS: A total of 100 consecutive patients with documented previous MI had electrocardiogram and CMR on the same day. Patients with acute MI within seven days were excluded. Left ventricular function and the size and transmural extent of MI were quantified in the three major arterial territories and correlated with the presence of QW. RESULTS: Subendocardial MI showed QW in 28%. Transmural MI showed NQW in 29%. Of all MIs, 48% were at some point transmural, and 99% of these were at some point non-transmural. As MI size and number of transmural segments increased, the probability of QW increased (anterior: total size chi-square = 53, p < 0.0001, transmural extent chi-square = 36, p < 0.0001; inferior: total size chi-square = 16, p = 0.001, transmural extent chi-square = 10, p = 0.001). These findings did not hold for lateral MI. In a multivariate model, the transmural extent of MI was not an independent predictor of QW when total size of MI was removed. The QW/NQW classification was a good test for size of MI (area under receiver operating characteristic curve: anterior 0.90, inferior 0.77). CONCLUSIONS: The QW/NQW distinction is useful, but it is determined by the total size rather than transmural extent of underlying MI. 相似文献
94.
95.
Norfloxacin and cisapride combination decreases the incidence of spontaneous bacterial peritonitis in cirrhotic ascites 总被引:3,自引:0,他引:3
Sandhu BS Gupta R Sharma J Singh J Murthy NS Sarin SK 《Journal of gastroenterology and hepatology》2005,20(4):599-605
BACKGROUND: Spontaneous bacterial peritonitis (SBP) is a serious complication of cirrhosis with ascites, having high recurrence despite antibiotic prophylaxis. Small bowel dysmotility and bacterial overgrowth have been documented to be related to SBP. The purpose of the present paper was (i) to study whether addition of a prokinetic agent to norfloxacin ameliorates the development of SBP in high-risk patients; and (ii) to identify risk factors for SBP development. METHODS: A prospective, single blinded, randomized controlled trial was conducted in high-risk cirrhotic patients with ascites who had either recovered from an episode of SBP or who had low ascitic fluid protein. Norfloxacin 400 mg once daily (group I) or norfloxacin 400 mg once daily with cisapride 20 mg twice a day (group II) was given and occurrence of side-effects of therapy and mortality were recorded. RESULTS: Of the 94 patients, 48 (51%) were in group I, and 46 (49%) in group II. The actuarial probability of developing SBP at 12 month in group I was 56.8% and in group II, 21.7% (P = 0.026). Treatment failure was observed in five patients (10%) in group I and none in group II (P = 0.003). The actuarial probability of death at 18 months was 20.6% in group I and 6.2% in group II (P = 0.1). Low serum albumin, low ascitic fluid protein and alcoholic cirrhosis were related to development of SBP (P < 0.05). Additionally, low serum albumin (2.8 g/dL), gastrointestinal bleeding, alcoholic cirrhosis and low ascitic fluid protein were significantly associated with multiple occurrences of SBP. CONCLUSIONS: Prophylaxis with norfloxacin and cisapride significantly reduces the incidence of SBP in high-risk cirrhosis patients; low serum albumin, low ascitic fluid protein and alcoholic cirrhosis predispose to the development of SBP in high-risk cirrhosis patients; and low ascitic fluid protein should also be considered as a risk factor for the development of SBP requiring prophylaxis. 相似文献
96.
97.
Makoto Izumi Munemasu Ryu Akihiro Cho Rajesh Gupta Vinoud Tiku Wataru Takayama Taichi Kawashima Shinichi Okazumi 《Journal of hepato-biliary-pancreatic sciences》2004,11(2):145-148
We report a case of a ruptured aneurysm in the anterior superior pancreaticoduodenal artery (PDA) with hypovolemic shock managed successfully by superselective transcatheter arterial embolization of the aneurysm. A75-year-old male presented to our hospital with hematemesis and melena. On admission, he was in shock. Angiography showed an aneurysm about 1?cm in diameter in the anterior superior PDA. However, extravasation of contrast medium was not seen owing to hypovolemic shock. A catheter was inserted into the aneurysm, and superselective microcoil embolization of the PDA aneurysm was successfully achieved. After the microcoil was inserted into the aneurysm itself, it was observed that duodenal vascularity and pancreaticoduodenal arcades were preserved and aneurysm was not present. There was no complication such as necrosis or abscess formation in the pancreas. The patient recovered and is doing well after 18 months of follow-up. Superselective transcatheter arterial embolization should be considered as the initial treatment of choice for all peripancreatic aneurysms. 相似文献
98.
Alex J Shah R Griffin SC Cale AR Cowen ME Guvendik L 《Asian cardiovascular & thoracic annals》2005,13(4):325-329
Prospective data of 3,120 consecutive patients who had elective coronary artery bypass were analyzed to identify patient profile, cost, outcome and predictors of those readmitted to the intensive care unit. Group A (n=3,002) had a single intensive care unit admission and group B (n=118) were readmitted within 30 days after surgery. Parsonnet score, EuroSCORE, age, body mass index, chronic obstructive airway disease, peripheral vascular disease, renal dysfunction, unstable angina, congestive cardiac failure, and poor left ventricular function were higher in group B. Bypass and crossclamp times were longer, and the prevalence of inotropic and balloon pump support, arrhythmias, myocardial infarction, re-exploration, blood loss and transfusion, cerebrovascular accident, wound infection, sternal dehiscence, and multisystem failure were higher in group B. Despite a 4-fold increase in cost of care, the mortality rate (32.4%) of patients readmitted to intensive care was 23-times higher than routine patients (1.4%). Crossclamp time>80 min, Parsonnet score>10, EuroSCORE>9, sternal dehiscence, ventricular arrhythmias, and renal failure predicted readmission. 相似文献
99.