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71.
土茯苓二氢黄酮醇类成分研究   总被引:12,自引:3,他引:12  
目的 :研究土茯苓的化学成分。方法 :用硅胶、大孔树脂、ODS柱色谱及HPLC方法进行分离纯化 ,根据理化性质和光谱数据进行结构鉴定。结果 :分离鉴定了 5个二氢黄酮醇苷类化合物 ,分别为落新妇苷 (1) ,新落新妇苷 (2 ) ,异落新妇苷 (3) ,新异落新妇苷 (4 ) ,(2R ,3R) 花旗松素-3′-O-β-D-吡喃葡萄糖苷 (5 )。 结论 :化合物 2 ,4 ,5为首次从该植物中分离得到。  相似文献   
72.
Atypical Shone''s complex is a rare congenital anomaly involving a left-sided obstructive lesion of two or three cardiovascular levels. A 70-year-old man with dyspnea on exertion was diagnosed with severe aortic stenosis (AS) with a bicuspid valve, complicated by severe aortic coarctation (CoA) and a double-orifice mitral valve. He underwent surgery for AS and CoA in one session. It is important to search for complicated malformations, even in cases of bicuspid aortic valve found in old age.  相似文献   
73.
BackgroundFrom 2004 to 2014, 821 colorectal cancer primary resections were conducted at our institution. Of these, 102 patients (12.4%) were older adults over 80 years old. underwent either the conventional laparotomy group (72 patients) or the hand-assisted laparoscopic surgery (HALS) group (30 patients).MethodsData were extracted for 102 patients over 80 years old who underwent primary resection for colorectal cancer and were divided into two groups: conventional laparotomy (CL) (n=72) and hand-assisted laparoscopy (n=30). Pre-operative characteristics and outcomes were compared.ResultsBaseline characteristics were similar between groups, except for age: CL group median 83.5 years old (range, 80–92 years old) and hand-assisted laparoscopy (HALS) group median 81.5 years old (range, 80–88 years old) (P=0.027). Pre-operative cardiac and lung function risk, performance status, and pathological classification stage (pStage) were almost similar between groups (P=0.668, P=0.176, P>0.999, P=0.217). No significant differences were found for operation time. The HALS group resulted in less blood loss (median 204 mL in the CL group and median 68 mL in the HALS group, P=0.003), shorter postoperative hospital stay (median was 18 days in the CL group and median was 12 days in the HALS group, P<0.001), and fewer postoperative wound infections (18 cases in the CL group and 2 cases in the HALS group, P=0.034). Five-year relapse-free survival (5Y-RFS) was 48.1% in the CL group and 73.3% in the HALS group (P=0.028). Five-year overall survival (5Y-OS) was 48.2% in the CL group and 73.3% in the HALS group (P=0.027).ConclusionsApproximately 70% of surgical treatment for patients over 80 years old with colorectal carcinoma were performed by CL. However, HALS had significant advantages including less blood loss, fewer wound infections, and shorter hospital stays. Therefore, HALS could proactively be considered to older adult patients with colorectal cancer.  相似文献   
74.
This study was carried out to understand the onset mechanism of adrenaline (ADR)-induced pulmonary edema (PE) and the effect of drugs related to the arachidonate cascade in a rabbit model. ADR was administered intravenously by a bolus injection to the rabbits at 50, 75 and 100 microg/kg. To evaluate the severity of PE, the lung-water ratio (LWR) was calculated as a ratio of the difference between wet and dry lung weight to dry lung weight. The PE incidence and LWR exhibited a dose-dependent increase, and LWR correlated with the left atrial pressure (LAP). The involvement of the arachidonate cascade was evaluated by the co-administration of flurbiprofen, a cyclooxygenase inhibitor; ozagrel, a thromboxane synthase inhibitor; and OP-2507 (15-cis-(4-n-propylcyclohexyl)-6,17,18, 19,20-pentanor-9-deoxy-6,9-alpha-nitriloprostaglandin F1 methyl ester), a prostaglandin I2 analogue. Co-treatment of the rabbits with ADR and flurbiprofen resulted in an increase in LAP and the incidence of PE, whereas co-administration of ozagrel did not exhibit any significant changes in the measured parameters. Conversely, OP-2507 reduced the LAP, PE incidence and LWR when co-administered with ADR. Rabbits co-treated with OP-2507 displayed an improved cardiac function. The results of these studies demonstrated the effectiveness of OP-2507 in protecting the lung and cardiac function from the ADR-induced PE.  相似文献   
75.
Juvenile myelomonocytic leukemia (JMML) is a rare myelodysplastic/myeloproliferative disorder that occurs during infancy and early childhood; this disorder is characterized by hypersensitivity of the myeloid progenitor cells to granulocyte–macrophage colony‐stimulating factor in vitro. JMML usually involves somatic and/or germline mutations in the genes of the RAS pathway, including PTPN11, NRAS, KRAS, NF1, and CBL, in the leukemic cells. Almost all patients with JMML experience an aggressive clinical course, and hematopoietic stem cell transplantation (HSCT) is the only curative treatment. A certain proportion of patients with somatic NRAS and germline mutations in CBL, however, have spontaneous resolution. A suitable treatment after diagnosis and conditioning regimen prior to HSCT are yet to be determined, but several clinical trials have been initiated throughout the world to develop suitable pre‐ or post‐allogeneic HSCT treatments and new targeted therapies that are less toxic, to improve patient outcome.  相似文献   
76.
Interstitial pneumonia (IP) is a major risk factor for lung adenocarcinoma (LADC). IP-related LADC predominantly develops in the bronchiolar metaplasia lining in honeycomb lesions. Kirsten rat sarcoma virus (KRAS) is the most common oncogene mutated in IP-related LADC. The present study examined the metaplastic epithelia in honeycomb lesions for KRAS mutations using digital droplet polymerase chain reaction (ddPCR), a sensitive method used to detect infrequent mutations. Significantly higher KRAS mutation variant allele frequencies (VAFs) were detected in the metaplastic lung epithelia from 13 patients with IP compared with those in 46 non-lesioned lung samples from patients without IP (G12V, P=0.0004, G12C, P=0.0181, and G12A, P=0.0234; Mann Whitney U test). Multivariate analyses revealed that higher KRAS G12V (logistic regression model; P=0.0133, odds ratio=7.11) and G12C (P=0.0191, odds ratio=5.81) VAFs in patients with IP were independent of confounding variables, such as smoking and age. In patients with IP, metaplastic epithelia exhibited significantly higher KRAS G12V and G12C VAFs compared with the non-lesioned counterparts (paired t-test; G12V, P=0.0158, G12C, P=0.0465). These results suggested that IP could increase KRAS mutations and supported the hypothesis that bronchiolar metaplasia could be a precursor for IP-related LADC.  相似文献   
77.
Ca-antagonistic activities of cerebral vasodilators, nicardipine and 1-(3,4-dimethoxyphenyl)-2-(4-diphenylmethylpiperazinyl)ethanol dihydrochloride (NC-1100) were tested on basilar and renal arteries, thoracic aorta and portal vein of rabbit, and rat vas deferens. Both the cerebral vasodilators used herein had a selectivity to basilar arteries. The selectivity to the basilar arteries is considered to be one of the factors in deciding the pharmacological property of the cerebral vasodilators.  相似文献   
78.
Background and HypothesisMachine learning approaches using structural magnetic resonance imaging (MRI) can be informative for disease classification; however, their applicability to earlier clinical stages of psychosis and other disease spectra is unknown. We evaluated whether a model differentiating patients with chronic schizophrenia (ChSZ) from healthy controls (HCs) could be applied to earlier clinical stages such as first-episode psychosis (FEP), ultra-high risk for psychosis (UHR), and autism spectrum disorders (ASDs).Study DesignTotal 359 T1-weighted MRI scans, including 154 individuals with schizophrenia spectrum (UHR, n = 37; FEP, n = 24; and ChSZ, n = 93), 64 with ASD, and 141 HCs, were obtained using three acquisition protocols. Of these, data regarding ChSZ (n = 75) and HC (n = 101) from two protocols were used to build a classifier (training dataset). The remainder was used to evaluate the classifier (test, independent confirmatory, and independent group datasets). Scanner and protocol effects were diminished using ComBat.Study ResultsThe accuracy of the classifier for the test and independent confirmatory datasets were 75% and 76%, respectively. The bilateral pallidum and inferior frontal gyrus pars triangularis strongly contributed to classifying ChSZ. Schizophrenia spectrum individuals were more likely to be classified as ChSZ compared to ASD (classification rate to ChSZ: UHR, 41%; FEP, 54%; ChSZ, 70%; ASD, 19%; HC, 21%).ConclusionWe built a classifier from multiple protocol structural brain images applicable to independent samples from different clinical stages and spectra. The predictive information of the classifier could be useful for applying neuroimaging techniques to clinical differential diagnosis and predicting disease onset earlier.  相似文献   
79.
80.
In the present paper, we report a case of rare collagenous gastritis. The patient was a 25‐year‐old man who had experienced nausea, abdominal distention and epigastralgia since 2005. Esophagogastroduodenoscopy (EGD) carried out at initial examination by the patient's local doctor revealed an extensively discolored depression from the upper gastric body to the lower gastric body, mainly including the greater curvature, accompanied by residual mucosa with multiple islands and nodularity with a cobblestone appearance. Initial biopsies sampled from the nodules and accompanying atrophic mucosa were diagnosed as chronic gastritis. In August, 2011, the patient was referred to Tohoku University Hospital for observation and treatment. EGD at our hospital showed the same findings as those by the patient's local doctor. Pathological findings included a membranous collagen band in the superficial layer area of the gastric mucosa, which led to a diagnosis of collagenous gastritis. Collagenous gastritis is an extremely rare disease, but it is important to recognize its characteristic endoscopic findings to make a diagnosis.  相似文献   
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