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31.
石杉碱甲类似物的研究II.N-甲基吡啶酮石杉碱甲类似物的合成 总被引:3,自引:1,他引:3
石杉碱甲(1)是从中草药石杉属植物千层塔(Lycopodium serratum Thunb.)中分得的一种高效可逆的乙酰胆碱酯酶抑制剂,临床试验证实它对早老性痴呆症有显著疗效。本文报道N-甲基吡啶酮石杉碱甲类似物2和3的合成。2-甲氧基-5-甲氧羰基-11-亚甲基-5,9-甲撑环辛-7-烯并吡啶(9)在乙腈中用三甲基氯硅烷和碘化钠选择性脱保护以定量的产率得吡啶酮10,再用甲醇钠和碘甲烷甲基化得N-甲基吡啶酮11,11经碱性水解,Curtius重排和氨基的脱保护得N-甲基吡啶酮石杉碱甲类似物2。通过类似的途径从中间体2-甲氧基-5-甲氧羰基-7-甲基-11-酮-5,9-甲撑环辛-7-烯并吡啶(14)合成了类似物3。类似物2和3的乙酰胆碱酯酶抑制活性均低于天然石杉碱甲。 相似文献
32.
Zielinsky A; Hirsh J; Straumanis G; Carter CJ; Gent M; Sackett DL; Hull R; Kelton JG; Powers P; Turpie AG 《Blood》1982,59(2):346-350
We have evaluated the fibrinogen/fibrin fragment E antigen assay as a diagnostic test in patients with clinically suspected venous thrombosis by comparing the results of this assay with venography in 272 patients. The result of the fragment E antigen assay was elevated in 79 of 80 patients with positive venograms for recent venous thrombosis (sensitivity 99%) and within the normal range in 161 of 192 patients with normal venograms (specificity 84%). The fragment E assay was also evaluated in 130 medical and surgical controls without evidence of venous thrombosis by leg scanning and the test was found to be relatively nonspecific. However, in the patient group under study, a correct clinical diagnosis of no thrombosis, based on a normal fragment E result, was made in 161 of 162 cases (negative predictive value of 99%). Therefore, a normal test result effectively excludes a diagnosis of venous thrombosis in clinically symptomatic patients. The assay, as currently performed, is technically demanding and takes 24 hr to complete. Therefore, it will have to be simplified before it can be applied to clinical practice. 相似文献
33.
BACKGROUND: Repeat hospitalizations of patients with atherosclerosis represent a considerable burden on the health care system. We sought to determine whether clopidogrel compared with aspirin decreases the need for rehospitalization for ischemia and bleeding. METHODS AND RESULTS: The Clopidogrel Versus Aspirin in Patients at Risk of Ischemic Events (CAPRIE) trial was a randomized, blinded, multicenter, trial of 19,185 patients with atherosclerotic disease manifested as recent ischemic stroke or myocardial infarction or symptomatic peripheral arterial disease. Without any double-counting of events, the number of rehospitalizations for ischemic events (defined as angina, transient ischemic attack, or limb ischemia) or bleeding events was determined for the entire cohort. There was a significant reduction in the total number of rehospitalizations for ischemic events or bleeding with clopidogrel use compared with aspirin (1502 vs 1673; P =.010) over an average of 1.6 years of treatment. This reduction in rehospitalization was consistent across individual outcomes of angina, transient ischemic attack, limb ischemia, and bleeding. Compared with aspirin, clopidogrel also resulted in a 7.9% relative risk reduction in a combined end point of vascular death, stroke, myocardial infarction, or rehospitalization for ischemic events or bleeding (15.1% to 13.7% at 1 year; P =.011). Adjusting for baseline prognostic variables, clopidogrel therapy was an independent predictor for reduction of vascular death, stroke, myocardial infarction, or rehospitalization for ischemic events or bleeding (P =.009). CONCLUSIONS: Treatment with clopidogrel results in a significant decrease in the need for rehospitalization for ischemic events or bleeding compared with aspirin. This meaningful end point tracks well with other, more traditional measures of outcome and has incremental value beyond such end points. 相似文献
34.
Sarvepalli Shashank Garber Ari Burke Carol A. Gupta Niyati Ibrahim Mounir McMichael John Morris-Stiff Gareth Bhatt Amit Vargo John Rizk Maged Rothberg Michael B. 《Digestive diseases and sciences》2021,66(6):2059-2068
Digestive Diseases and Sciences - Inadequate bowel preparation (IBP) is associated with reduced adenoma detection. However, limited research has examined the impact of different commercial bowel... 相似文献
35.
Franchi Francesco Schneider David J. Prats Jayne Fan Weihong Rollini Fabiana Been Latonya Taatjes-Sommer Heidi S. Bhatt Deepak L. Deliargyris Efthymios N. Angiolillo Dominick J. 《Journal of thrombosis and thrombolysis》2022,54(3):373-381
Journal of Thrombosis and Thrombolysis - Low dose enteric-coated aspirin (EC-ASA) is routinely used for secondary cardiovascular event prevention. However, absorption of EC tablets is poor, which... 相似文献
36.
B D Bhatt F V Meriano T L Phipps H Ho M J Zuckerman 《Journal of clinical gastroenterology》1990,12(1):14-16
H2-antagonists are frequently used in the management of upper gastrointestinal (UGI) hemorrhage despite their lack of proven efficacy. In order to determine the pattern of H2-antagonist usage for this indication, we retrospectively reviewed the charts of 137 patients admitted with acute UGI bleeding over a 1-year period at two teaching hospitals in West Texas. An H2-antagonist was ordered in 89% of patients (77%) intravenous, 12% oral). It was administered within 2 h of admission in 25% of these patients, within 4 h in 54%, and within 8 h in 78%. An H2-antagonist was ordered among the initial six orders in 49% and among the initial 10 orders in 77% of patients. Considering orders for specific therapies, an H2-antagonist was in the initial three orders in 60% of patients and among the initial six orders in 97%. Of the patients who were prescribed an H2-antagonist and who also had upper endoscopy, the drug was ordered prior to endoscopy in 86%. This review of H2-antagonist usage in the management of acute UGI bleeding has identified a prescribing pattern of writing for these drugs early in the sequence of order writing, with the drugs being given early in the course of hospitalization. 相似文献
37.
Elena S. Resnick Priyanka Bhatt Peter Sidi Charlotte Cunningham-Rundles 《Journal of clinical immunology》2013,33(1):40-48
Purpose
To use International Classification of Disease Codes (ICD-9) codes to investigate primary immune deficiency (PID) in New York State.Methods
We investigated the diagnosis of Primary Immune Deficiency (PID) in New York State (NYS) using the Statewide Planning and Research Cooperative System (SPARCS) database, a comprehensive data reporting system that collects ICD-9 codes for each patient hospitalized in NYS.Results
From 2000–2004 there were 13,539,358 hospitalizations for 4,777,295 patients; of these, 2,361 patients (0.05 %) were diagnosed with one or more of the ICD-9 codes for PID. Antibody defects were the most common diagnoses made. The PID population had significantly more Caucasians, and fewer African American or Hispanic subjects compared to the general population. Subjects with PID codes were younger, had longer hospitalizations, were less likely to have Medicare and more likely to have Medicaid or Blue Cross insurance. Most hospitalizations were due to respiratory and infectious diseases. Most patients resided in the most populous counties, Kings, New York and Queens, but the distribution of home zip codes was not proportional to county populations.Conclusions
These data provide useful information on incidence and complications of selected PID diagnoses in one large state. 相似文献38.
39.
VY Kong B Sartorius DL Clarke 《Annals of the Royal College of Surgeons of England》2015,97(5):390-395
IntroductionAcute appendicitis in the developing world has a markedly different disease profile to that in the developed world.MethodsA retrospective study was undertaken over a four-year period at a university hospital in South Africa to review the disease spectrum and the clinical outcome of acute appendicitis.ResultsA total of 1,004 patients (54% male, median age: 18 years) with intraoperatively confirmed appendicitis were reviewed. Over half (56%) were from the urban district within the city of Pietermaritzburg and the remaining 44% were from the rural health district. The median duration of illness from onset to definitive care was 4 days. Sixty per cent of appendices were perforated and associated with intra-abdominal contamination. Forty per cent of patients required reoperation to control intra-abdominal sepsis. Ten per cent required admission to the intensive care unit. The median overall length of hospital stay was 5 days. The mortality rate was 1%.Rural patients had a longer median duration of illness (3 vs 5 days, p<0.001) as well as a more advanced disease profile associated with perforation and severe intra-abdominal sepsis (19% vs 71%, p<0.001). Female patients had a longer median duration of illness (3 vs 4 days, p<0.001), were more likely to present with severe intra-abdominal sepsis (31% vs 54%, p<0.001) and were more likely to require a laparotomy (50% vs 73%, p<0.001). The total cost of managing the entire cohort of 1,004 patients over the 4-year period was £2,060,972.ConclusionsAcute appendicitis in South Africa is a serious disease associated with significant morbidity. Late presentation is common. Female and rural patients have the worst clinical outcomes, with significant cost to the health system. 相似文献
40.