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11.
红景天属植物中红景天甙的高效液相色谱分析   总被引:11,自引:0,他引:11  
采用ODS柱,以甲醇—水(2:8)为流动相,在276nm检测波长下,测定了大花红景天、互生红景天、喜马红景天、云南红景天和四裂红景天5种生药以及大花红景天提取物10个样品中的红景天甙的含量。  相似文献   
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Samoszuk  MK; Espinoza  FP 《Blood》1987,70(2):597-599
Eosinophil granules are intensely autofluorescent when excited by green light. To determine if eosinophils degranulate in the bone marrows of patients with a variety of diseases, we used green light epifluorescence microscopy to examine deparaffinized and dezenkerized sections of 49 bone marrow core biopsies. In 14 of the biopsies, there was striking extracellular deposition of intensely autofluorescent eosinophil granules in addition to numerous intact eosinophils. Among the 14 specimens with extracellular autofluorescence were seven cases of leukemia, four cases of non-Hodgkin's lymphoma, two cases of myelofibrosis, and one case of pancytopenia with eosinophilia. In the remaining 35 specimens, only intact eosinophils were identifiable. There was no extracellular autofluorescence in three normal marrows, four marrows from AIDS patients, or three biopsies from patients with idiopathic thrombocytopenic purpura (ITP). We conclude that green light epifluorescence microscopy identifies extracellular deposits of eosinophil granules in bone marrow biopsies of some neoplastic disorders and in diseases associated with reticulin fibrosis.  相似文献   
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BACKGROUND: Pantoprazole is a substituted benzimidazole which is a potent inhibitor of gastric acid secretion by its action upon H+, K+- ATPase. METHODS: Pantoprazole 40 mg and 80 mg were compared in a randomized double-blind study in 192 out-patients with stage II or III (Savary-Miller classification) reflux oesophagitis. Patients received either pantoprazole 40 mg (n = 97) or pantoprazole 80 mg (n = 95), once daily before breakfast for 4 weeks. Treatment was extended for a further 4 weeks if the oesophagitis had not healed. RESULTS: After 4 weeks complete healing of the reflux oesophagitis was seen in 78% of protocol-correct patients given pantoprazole 40 mg daily (n = 86), and in 72% in the 80 mg (n = 87) group. The cumulative healing rates after 8 weeks were 95 and 94%, respectively (P > 0.05, Cochran-Mantel- Haenszel), and time until healing of oesophagitis comparable in both groups. Differences between doses were also not significant in an intention-to-treat analysis. Both dosing schedules were well tolerated and the patients experienced remarkable symptom relief. No adverse event or changes in laboratory values of clinical significance could definitely be ascribed to the trial medication. CONCLUSION: The 40 mg pantoprazole dosage is comparable to 80 mg in reflux oesophagitis, both in efficacy and tolerability.  相似文献   
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AIM:To evaluate the potential of S-nitroso-N-acetyl-cysteine(SNAC)in inhibition of lipid peroxidation andthe effect of oral SNAC administration in the preventionof nonalcoholic fatty liver disease(NAFLD)in an animalmodel.METHODS:NAFLD was induced in Wistar male rats bycholine-deficient diet for 4 wk.SNAC-treated animals(n=6)(1.4 mg/kg/day of SNAC,orally)were comparedto 2 control groups:one(n=6)received PBS solutionand the other(n=6)received NAC solution(7 mg/kg/d).Histological variables were semiquantitated with respectto macro and microvacuolar fat changes,its zonal dis-tribution,foci of necrosis,portal and perivenular fibro-sis,and inflammatory infiltrate with zonal distribution.LOOHs from samples of liver homogenates were quanti-fied by HPLC.Nitrate levels in plasma of portal vein wereassessed by chemiluminescence.Aqueous low-densitylipoprotein(LDL)suspensions(200 μg protein/mL)wereincubated with CuCl_2(300 μmol/L)in the absence andpresence of SNAC(300 μmol/L)for 15 h at 37℃.Extentof LDL oxidation was assessed by fluorimetry.Linoleicacid(LA)(18.8 μmol/L)oxidation was induced by soy-bean lipoxygenase(SLO)(0.056 μmol/L)at 37℃ in the presence and absence of N-acetylcysteine(NAC)andSNAC(56 and 560 μmol/L)and monitored at 234 nm.RESULTS:Animals in the control group developed mod-erate macro and microvesicular fatty changes in peripor-tal area.SNAC-treated animals displayed only discretehistological alterations with absence of fatty changes anddid not develop liver steatosis.The absence of NAFLD inthe SNAC-treated group was positively correlated with adecrease in the concentration of LOOH in liver homog-enate,compared to the control group(0.7±0.2 nmol/mgvs 3.2±0.4 nmol/mg protein,respectively,P<0.05),whileserum levels of aminotransferases were unaltered.Theability of SNAC in preventing lipid peroxidation was con-firmed in in vitro experiments using LA and LDL as modelsubstrates.  相似文献   
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BACKGROUND: Glutamine has been widely used in treatment of small bowel syndrome and its metabolic effects on the small intestine are well known, however, it has been little studied its effects on hepatic metabolism under this condition. AIM: To verify through experimental model, a glutamine based supplemental diet, administered via oral to rats submitted to massive intestinal resection, evaluating weight evolution and hepatic glycogen content. MATERIAL AND METHODS: Male rats, Wistar, were allocated into three groups to undergo enterectomy. Following diets were applied: with glutamine (G group), without glutamine (NG group), and standard diet from the laboratory (R group). All animals had massive small intestine resection including ileocecal valve removal. After 20 days, all animals were sacrificed. The liver was removed to histological analysis by light microscopy. Slides were stained by periodic acid of Schiff with diastasis. RESULTS: All animals lost weight from the beginning to the end of experiment. Comparing weight loss average expressed in percentage, there was no difference statistically significant on this variance. In analyzed groups, the hepatic glycogen content did not differ statistically, in the histological method evaluated. CONCLUSION: Glutamine feeding via oral did not influence weight loss reduction of animal submitted to massive intestinal resection and did not stimulate glycogen synthesis and storage into hepatocytes.  相似文献   
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The femur length/abdominal circumference ratio, expressed as FL/AC X 100, was determined in 156 fetuses and evaluated as a predictor of fetal macrosomia within one week prior to delivery. The normal range (mean +/- 2 SD) in the 105 normal-weight fetuses was 22.0 +/- 2, while the normal range in the 51 macrosomic fetuses was 20.5 +/- 2; these differences were highly significant (P = less than .0001). The predictive power of a positive ratio was 68%, with a sensitivity of 63%. This ratio was particularly useful in the subset (n = 9) of macrosomic fetuses whose mothers were diabetic, correctly identifying 89% of this group. Because it is age independent, this ratio should prove most helpful in identifying fetuses at risk for macrosomia in patients whose dates are not known, since it may become abnormal before the fetal weight falls above the 90th percentile at term (3,900 g). In patients whose dates are known, early fetal macrosomia is best predicted by evaluating the abdominal circumference against normal standards for age.  相似文献   
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DA Christakis  FP Rivara 《Pediatrics》1998,101(5):825-830
BACKGROUND: The increasing complexity of medical care and a desire to increase quality and control costs have led to growing use of clinical practice guidelines (CPGs). It is unclear how helpful these guidelines are to the practitioners expected to use them. We surveyed pediatricians about their knowledge and impressions of four well-publicized CPGs: the American Academy of Pediatrics' "Practice Parameter for Hyperbilirubinemia in Newborns" (hyperbilirubinemia), "A Guideline for the Management of Febrile Infants" (fever), the Agency for Health Care Policy and Research's "Guideline for Otitis Media With Effusion" (otitis), and the US Preventive Services Task Force Guide to Clinical Preventive Services (preventive care). OBJECTIVES: 1) What percentage of practicing pediatricians are aware of these guidelines? 2) How helpful do they find them? 3) What are practitioners' perceived limitations of these guidelines? 4) Have these guidelines affected provider behavior? 5) Are there features of a provider's training or practice that are associated with changing practice as a result of guidelines? DESIGN: A national survey of 600 pediatricians selected at random from the American Medical Association master file. RESULTS: A total of 300 of 555 eligible participants (54%) returned surveys. Of the respondents, 66% were aware of the hyperbilirubinemia guideline, 64% of the fever guideline, 50% of the otitis guideline, but only 16% knew of the preventive care guidelines. Mean helpfulness scores (1 to 10 scale, where 1 = "not at all helpful" and 10 = "extremely helpful") ranged from 3.67 to 6.67 for the different guidelines. In terms of limitations, 15% to 33% of respondents reported that CPGs were "too cookbook," 6% to 19% reported that they were "too time-consuming," and 4% to 16% reported that they were "too cumbersome." Additional reported limitations were believing that a guideline left no room for personal experience and judgment, concern of increased liability risk, and poor parental acceptance of CPG recommendations. The proportions reporting change in management as a result of a CPG were 28% for the hyperbilirubinemia guideline, 36% for the fever guideline, 19% for the preventive care guidelines, and 28% for the otitis guideline. Mean helpfulness scores reported by nonuniversity-affiliated physicians were significantly higher than those reported by university-affiliated physicians. In a regression model of respondents aware of a particular guideline, more recent graduation from medical school and increased helpfulness scores were associated with guideline-related behavior change. CONCLUSION: In their present form, CPGs are not perceived as very helpful by most practitioners. More recent medical school graduates and nonuniversity-affiliated physicians are more likely to find them helpful and more likely to change their behavior because of them.  相似文献   
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