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排序方式: 共有272条查询结果,搜索用时 15 毫秒
31.
宁夏贝母化学成分的研究 总被引:3,自引:0,他引:3
从宁夏贝母(Frdillapia taipaiensis P. Y. Li var. ningxiaensis Y. K. Yang et. J. K. Wu)的鳞茎中分得六个异甾体生物碱成分,鉴定为宁贝素(taipaienine,Ⅰ)、川贝酮(chuanbeinone,Ⅱ)、西贝素(imperialine,Ⅲ)、贝母乙素(verticinone,Ⅳ)、贝母辛(peimissine,Ⅴ)和异贝母甲素(isoverticine,Ⅵ).其中T为一新C-去甲-D-高甾生物碱。应用波谱分析(IR,MS,1HNMR和13CNMR)等确定了它们的化学结构。 相似文献
32.
Computed tomography (CT) was used to study 25 patients with congenital conductive hearing loss and normal external auditory canals. Deformities were subdivided according to ossicular, fenestral, and cholesteatomatous origin. Isolated ossicular deformities were found in 14 patients (five bilateral), cholesteatoma in eight, oval-window nondevelopment (with ossicular deformity) in one, and normal studies in two (congenital stapes fixation at the level of the annular ligament). Ossicular deformities may be subdivided into incudostapedial disconnections into incudostapedial disconnections (most common), malleoincudal fixations, and stapes fixations. Most are due to developmental anomaly of the first or second branchial arch. The stapes has a dual origin (second arch and otic capsule). A cholesteatoma is defined as congenital only if there is no history of otitis and the tympanic membrane is intact. In this series, six were in the middle ear proper, and two were within the attic beyond otoscopic view. Their CT appearance, with one exception, was essentially identical to that of acquired lesions. 相似文献
33.
Which factors may influence the number of hours spent per week in cafes, and the amount of alcohol consumed in licensed premises, by urban cafe guests in Norway? In 1991 a comprehensive questionnaire survey was undertaken among 1053 visitors to 41 licensed cafes in Oslo, Norway. The five most important predictors of time spent in cafes were: household situation (β=0.20), occupation (β= 0.18), personal economic resources and sex (both β= 0.15) and age (β= 0.11). These factors were also significant predictors of the number of days during the past 4 weeks the respondents had drunk jour glasses or more of alcohol in cafes. Men, people living with others, people with poor economic resources and people not engaged in paid employment or education were the ones who reported spending the most hours per week and the most episodes of “heavy” drinking in cafes during a 4-week period. Visiting and drinking in cafes may be a way of structuring everyday life. 相似文献
34.
CENGIZ GIRGIN AKIF SEZER RUEN UÇ MURAT ERMETE UUR ÖZKAN GÖZEN GÜREL 《International journal of urology》2003,10(10):525-529
BACKGROUND: We evaluated the treatment outcomes of non-transitional cell carcinoma (non-TCC) cases after radical cystectomy. METHODS: Radical cystectomy was performed in 259 invasive bladder cancer patients in our department and of these, 59 (22.7%) were non-TCC. Primary squamous cell carcinomas (SCC), adenocarcinomas and undifferentiated cancers (UC) were grouped as non-TCC of the bladder. Of the 59 non-TCC; 32 SCC, 20 UC, five adenocarcinoma and two sarcomatoid tumor cases were demonstrated. RESULTS: The 5-year disease-specific survival rate of TCC and non-TCC cases were 48.9 and 28.2%, respectively (P = 0.0016). The 5-year disease-specific survival rates of SCC and UC were 25.1 and 23.4%, respectively. The median survival time of SCC, UC and adenocarcinoma cases were 19, 12 and 6 months, respectively (P = 0.4579). The disease-specific survival rates of TCC and non-TCC cases at stage pT2NoMo were 79.1 and 27.2%, respectively (P = 0.0000). The median survival time of SCC, UC and adenocarcinoma cases were 19, 12 and 13.3 months, respectively, for the same stage. The survival time of TCC, SCC and UC cases at stage pT3NoMo were 23, 26 and 45 months, respectively (P = 0.2307). The median survival time at stages pT2-3N1Mo for the same groups were 18, 16 and 11 months, respectively (P = 0.0939). CONCLUSION: The study presented here demonstrates that both TCC and non-TCC cases have poor survival rates in locally advanced disease and that at the pT2NoMo stage the prognosis of non-TCC cases is poor when compared with TCC cases. 相似文献
35.
EN Smit JM Dijkstra TA Schnater E Seerat FAJ Muskiet ER Boersma 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(7):690-695
Abstract Erythrocyte fatty acids and plasma vitamin E concentrations were determined in 47 grade 2 and 21 grade 3 malnourished Pakistani children (ages 4–56 months). Data were compared with those of 26 age- and sex-matched apparently healthy controls. Evaluation with three statistical approaches revealed that both grade 2 and grade 3 malnourished children had decreased erythrocyte ω6 fatty acids and to a lesser extent decreased ω3 fatty acids. These decreases were compensated for by increased ω9 fatty acids. The patients tended to have lower plasma vitamin E concentrations. We conclude that malnourished Pakistani children have low essential fatty acid status, notably those of the ω6 series. The combination of low erythrocyte 22:6ω3 and a low 22:5ω6/22:4ω6 ratio in grade 2 patients suggests low Δ4-desaturation activity, which may be due to impaired peroxisomal β-oxidation. 相似文献
36.
S. MJØEN A. LANGSLET S. E. TANGSRUD A. SUNDBY 《Acta paediatrica (Oslo, Norway : 1992)》1982,71(5):711-715
ABSTRACT. In the present study, auditory brainstem responses (ABR) were recorded in 60 highrisk neonates in the intensive care unit selected by the following criteria: Birth-weight <2000 g, hyperbilirubinemia requiring phototherapy or exchange transfusion, idiopathic respiratory distress syndrome, artificial ventilation, asphyxia, sepsis or meningitis, intracranial haemorrhage, neurological symptoms and potential ototoxic medication (aminoglycoides, furosemide). The infants tested ranged in gestational age from 27-44 weeks. The ABR testing was performed in a sound-proof room using the Madsen (ERA-74) equipment. Four infants did not reveal responses to 70 dB HL ("nonresponders"), and the total of 10 neonates (16.6%) had abnormal ABR-tests, when the physiological changes related to gestational age and conceptional age (gestational age plus the age after birth) were taken into account. The 10 neonates with abnormal tests were reexamined after discharge, and in six there were no improvement of threshold sensitivity. Three of the "nonresponders" were retested several times within the two years after birth (one died at age 18 months of pertussis), and none of them revealed ABR at stimulus intensity of 70 dB HL. They all attend an audiological training program started at age of six months as a consequence of the early diagnosis of impaired auditory function. It is our opinion that a routine ABR-evaluation should be performed on high risk neonates (criteria mentioned above) in the newborn intensive care unit. Retesting of infants with abnormal responses within three months, and several times within the next two years if abnormal responses persist, is important. Transient impairment of auditory functions is not uncommon in these infants. However, the children with persisting hearing impairment should be discovered early to attend an early audiological training program. 相似文献
37.
The identification of small numbers of leukemic cells in the cerebrospinal fluid (CSF) presents a diagnostic problem in the treatment of children with acute lymphoblastic leukemia (ALL). We adapted a latex sphere rosetting technique to allow us to identify simultaneously cell surface markers and cell morphology in 199 CSF samples from 34 patients and 14 control subjects. In patients without leukemic meningitis, the majority of CSF lymphocytes (69%) were found to be mature T cells positive for OKT11. A much smaller number of cells (8%) were found to be B cells positive for la. In these children, only 3% of CSF lymphoid cells expressed the common acute lymphoblastic leukemia antigen (CALLA). Similar results were found in the control subjects. By contrast, 28 CSF samples from nine children with varying numbers of CSF lymphoblasts had much greater proportions of CALLA- and la-positive CSF cells (24% to 96%). Leukemic meningitis was present in one of these patients and later developed in four others. However, three patients with small numbers of lymphoblasts present but with low proportions of CALLA-positive CSF cells (less than 5%) subsequently had normal CSF examinations. We found the use of this rosetting technique valuable in providing information complementary to that obtained from cell morphology alone about the possible malignant nature of small numbers of lymphoblast-like CSF cells seen on cytocentrifuge preparations in children with ALL. 相似文献
38.
The pathogenesis of diphenylhydantoin-induced pure red cell aplasia was investigated in the case of a 32-year-old man who developed pure red cell aplasia while he was under treatment with diphenylhydantoin. The patient's serum IgG purified from serum drawn at the time of diagnosis suppressed normal allogeneic marrow colony-forming (CFU-E) and burst- forming (BFU-E) and autologous blood BFU-E growth in vitro only in the presence of diphenylhydantoin. This IgG-diphenylhydantoin complex had no effect on CFU-GM growth in vitro. Normal IgG or patient's IgG purified from serum drawn after the remission of red cell aplasia had no effect on erythroid colony formation in vitro in the presence of diphenylhydantoin. The IgG-diphenylhydantoin complex exerted no direct cytotoxic effect on normal marrow erythroblasts, CFU-E, and BFU-E, nor did it interfere with the action of erythropoietin on marrow erythroblasts. These studies suggest that diphenylhydantoin-induced red cell aplasia is immunologically mediated through an IgG inhibitor, which requires the presence of the drug to suppress erythroid colony formation in vitro. This inhibitor seems to exert its effect on erythroid progenitors at or beyond the stage of differentiation of CFU- E, but not on erythroblasts. 相似文献
39.
40.
Kesse E Boutron-Ruault MC Norat T Riboli E Clavel-Chapelon F;EN Group 《International journal of cancer. Journal international du cancer》2005,117(1):137-144
A protective effect of calcium and/or dairy products on colorectal cancer has been reported in epidemiological studies but the findings are considered inconsistent. In particular, it is unclear whether they act at a particular step of the adenoma-carcinoma sequence. To investigate the effect of dairy product consumption and dietary calcium, vitamin D and phosphorus intake on the adenoma-carcinoma sequence in the French E3N-EPIC prospective study. The population for the study of risk factors for adenomas was composed of 516 adenoma cases, including 175 high-risk adenomas, and of 4,804 polyp-free subjects confirmed by colonoscopy. The population for the colorectal cancer study was composed of 172 cases and 67,312 cancer-free subjects. Diet was assessed using a self-administered questionnaire completed at baseline. There was a trend of decreasing risk of both adenoma (ptrend=0.04) and cancer (ptrend=0.08) with increasing calcium intake, with RRs for adenoma and cancer of 0.80 (IC 95%=0.62-1.03) and 0.72 (95% CI=0.47-1.10), respectively, in the fourth quartile compared to the first. A protective effect of dairy products on adenoma (RRQ4 vs. Q1=0.80, 95% CI=0.62-1.05, ptrend=0.04) was observed and of milk consumption on colorectal cancer (RRQ4vs. Q1=0.54, 95% CI=0.33-0.89, ptrend=0.09), although the latter did not reach significance. Phosphorus intake also decreased the risk of adenoma (RRQ4 vs. Q1=0.70, 95% CI=0.54-0.90, ptrend=0.005). No vitamin D effect was identified. Our data support the hypothesis that calcium, dairy products and phosphorus exert a protective effect at certain steps of the adenoma-carcinoma sequence. 相似文献