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81.
羽叶三七叶中甙类成分的研究   总被引:3,自引:0,他引:3  
从羽叶三七叶中分离到十三种甙类成分,经FAB-MS,13CNMR谱,双照射1HN-MR谱,1H-1H COSY谱及与标准品直接对照,证明十一种为已知化合物,分别为人参皂甙F1(Ⅰ),F2(Ⅱ),F3(Ⅲ),Rg2(Ⅳ),Ra(Ⅴ),Rd(Ⅵ),Rb1(Ⅷ),Rb3(Ⅷ),24(S)-假人参甙F11(Ⅸ),人参黄酮(Ⅹ)和珠子参甙F1(Ⅺ);另外两种为新的达玛烷型皂甙,命名为羽叶三七甙F1(Ⅻ)和F2(ⅫⅠ),并确定其化学结构。同时修正珠子参甙F3的结构。进一步阐明人参黄酮甙结构中的两个糖的连接方式。  相似文献   
82.
Splanchnic artery aneurysms and pseudoaneurysms: transcatheter embolization   总被引:9,自引:0,他引:9  
Baker  KS; Tisnado  J; Cho  SR; Beachley  MC 《Radiology》1987,163(1):135-139
Over the past 7 years, eight patients with splanchnic artery aneurysms and pseudoaneurysms were studied and treated. Transcatheter embolization resulted in occlusion of the lesions in all eight patients. Potentially risky and difficult surgery was avoided completely in four patients. Three patients had elective surgery at a later date when their condition was more stable. The remaining patient had definitive surgery after embolization. Transcatheter embolization should be the initial treatment of choice in splanchnic artery aneurysms and pseudoaneurysms.  相似文献   
83.
Bone marrow disorders: characterization with quantitative MR imaging   总被引:10,自引:0,他引:10  
Smith  SR; Williams  CE; Davies  JM; Edwards  RH 《Radiology》1989,172(3):805-810
Thirty patients with various hematologic disorders and 15 healthy control subjects underwent quantitative magnetic resonance (MR) imaging of the lumbar spine with spin-echo techniques. Images of patients with infiltrative bone marrow disorders showed significantly more prolonged T1 times than those of control subjects (P less than .001). It was not possible to distinguish different diffuse infiltrative bone marrow disorders on the basis of T1 values. Aplastic anemia could be distinguished from normality because of significantly shortened T1 (P less than .001). A significant correlation was seen between T1 and bone marrow cellularity (r = .74, P less than .001). T2 was of no value in the characterization of bone marrow disorders. Quantitative MR imaging dose not improve the diagnostic potential of bone marrow imaging in the detection of diffuse marrow infiltrates.  相似文献   
84.
85.
The elbow: MR features of nerve disorders   总被引:3,自引:0,他引:3  
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86.
We have reviewed the demographic characteristics of, and report abnormalities noted in, the de-novo growth and development of a paid oocyte donation programme. The personal profiles of all prospective oocyte donors were reviewed. Acceptance or rejection of candidates was based upon screening the results of medical, genetic and psychological testing. A total of 603 candidates initially responded to our advertisement. From this pool, 313 individuals were considered suitable and contacted by telephone. Following further conversation, 176 women were scheduled an entry interview. On completion of the formal screening process, 17.6% (n = 31) of those actually interviewed were denied entry. Thus, from the initial interested parties, only 23% of women wishing to participate in oocyte donation were considered suitable candidates. Given the high attrition rate, we concluded that the need for rigorous and thorough medical, psychological and genetic testing is mandatory for the establishment of a donor registry. Furthermore, professional counselling of prospective donors with respect to the results of tests and the implications of test results with respect to their future medical and reproductive health, are important parts of providing comprehensive care.   相似文献   
87.
d,l-15(R)-15-Methyl-PGF methyl ester 11-trimethylsilyl ether(II)wasprepared from selective monosilylation of d,l-15(R)-15-methyl-PGFmethyl ester(I) withtrimethylsilyldiethylamine in acetone. Oxidation of(II ) with Collin's reagent gave d,l-15(R)-15-methyl-PGE2 methyl ester 11-trimethylsilyl ether(III)which,without purification,was converted to d,l-15(R)-15-methyl-PGE2 methyl ester(IV)under mild acidic conditions.  相似文献   
88.
89.
BACKGROUND.: The effectiveness of health promotion activity in general practiceon risk factor reduction for coronary heart disease remainsthe subject of active debate. OBJECTIVE.: The study aimed to assess the impact of practice-based healthcheck-ups on health behaviours over a 2-year period. METHOD.: A general practice cohort of 7123 patients from 18 practiceswas surveyed. Eight hundred and forty (12%) patients had beenoffered a heafth check within a 12-month period from September1992 and 621 (9%) received one. Two hundred and fifty patients(40%) were asked back for follow-up after their health check. RESULTS.: Over a 2-year period there was no difference in smoking cessation,alcohol consumption, weight loss nor the amount of exercisetaken between those who attended for a health check and thosewho did not. The food score chosen to assess dietary change(Oxcheck) showed a statistically significant 1.16-point risefor the whole sample over the survey period. There was a significantdifference in mean food score change between heafth check attendersand non-attenders (Mann-Whitney U test: P << 0.002). Maintenanceof dietary improvement over a 2-year period was not affectedby health check attendance. CONCLUSIONS.: This study confirms the low impact of health checks on the selfreported modification of cardiovascular risk factors and showsthat maintenance of appropriate health behaviour change is nomore likely in those who have received a health check. Keywords. Health promotion, general practice.  相似文献   
90.
The objectives were to determine quantitative liver function prospectively in patients with rheumatoid arthritis (RA) treated with low-dose methotrexate (MTX), to search for risk factors for a loss of quantitative liver function and to assess the relationship between quantitative liver function and histological staging. A total of 117 patients with RA (ACR criteria, 85 women, mean age 59 yr) had measurements of galactose elimination capacity (GEC), aminopyrine breath test (ABT) and liver enzymes [aspartate amino transferase (AST), alanine amino transferase (ALT), alkaline phosphatase (AP), 7-glutamyl transferase (GGT), bile acids, bilirubin, albumin] before treatment with weekly i.m. MTX injections and every year thereafter. In 16 patients, liver biopsies were performed. Before the introduction of MTX, mean GEC was 6.6 mg/min/kg [5th to 95th percentile (5-95 PC) 5.1- 8.5; reference range 6.0-9.1] and mean ABT was 0.80% kg/mmol (5-95 PC 0.42-1.30: reference range 0.6-1.0). During treatment with MTX [mean weekly dose 11.8 mg (5-95 PC 5.4-20.2), mean observation period 3.8 yr (5-95 PC 0.4-6.9)], significant declines of GEC (-0.12 mg/min/kg per year. t = 3.30, P < 0.002) and ABT (-0.06% kg/mmol per year, t = 4.81, P < 0.001) were observed. Negative correlations were found between the annual change in GEC and GEC at baseline (Rs = -0.40, P < 0.0001), and the annual change in ABT and ABT at baseline (Rs = -0.43, P < 0.0001). No correlations were found between the annual change in GEC or ABT and weekly MTX dose, age or percentage of increased liver enzymes, and no effect of a history of alcohol consumption > 30 g/week became evident. Two patients with Roenigk grade III had impaired quantitative liver function, while 14 patients with Roenigk grades I and II exhibited a high variability of GEC and ABT from normal to abnormal values. The continuous declines in GEC and ABT observed deserve attention in patients with prolonged treatment. Patients with a low GEC or ABT at baseline seem not to be at increased risk for a further loss of quantitative liver function. An impaired GEC or ABT does not necessarily concur with hepatic fibrosis on histological examination.   相似文献   
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