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2.
麦冬类中药组织切片计算机三维重建图鉴   总被引:9,自引:0,他引:9  
利用计算机技术实现麦冬类中药组织连续切片三维重建与动态显示,为计算机辅助生药学鉴定和教学提供了新的三维图像技术和研究资料。  相似文献   
3.
Microsurgical vasovasostomy has become a common urologic procedure. A successful anastomosis is related to good mucosal alignment and a water-tight anastomosis rather than to a specific technique. The presence of vasal or epididymal sperm granulomas as well as antisperm antibodies will also influence postoperative pregnancy rates.  相似文献   
4.
用混合粘合剂碳糊电极测定丁螺环酮   总被引:6,自引:1,他引:5  
用混合粘合剂碳糊电极测定丁螺环酮张正奇,曾鸽鸣,刘传桂,黎艳飞(湖南大学化学化工系,长沙410082)碳糊电极无毒,制作方便,表面更新容易,应用电位范围广,在药物分析中已有应用[1~5]。我们在液体石腊中加入添加剂,组成混合粘合剂,可显著改善电极的检...  相似文献   
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AIMS: Diabetic ketoacidosis (DKA), a life-threatening acute complication of Type 1 diabetes, may be preventable with frequent monitoring of glycaemia and ketosis along with timely supplemental insulin. This prospective, two-centre study assessed sick day management using blood 3-hydroxybutyrate (3-OHB) monitoring compared with traditional urine ketone testing, aimed at averting emergency assessment and hospitalization. METHODS: One hundred and twenty-three children, adolescents and young adults, aged 3-22 years, and their families received sick day education. Participants were randomized to receive either a blood glucose monitor that also measures blood 3-OHB (blood ketone group, n = 62) or a monitor plus urine ketone strips (urine ketone group, n = 61). All were encouraged to check glucose levels > or = 3 times daily and to check ketones during acute illness or stress, when glucose levels were consistently elevated (> or = 13.9 mmol/l on two consecutive readings), or when symptoms of DKA were present. Frequency of sick days, hyperglycaemia, ketosis, and hospitalization/emergency assessment were ascertained prospectively for 6 months. RESULTS: There were 578 sick days during 21,548 days of follow-up. Participants in the blood ketone group checked ketones significantly more during sick days (276 of 304 episodes, 90.8%) than participants in the urine ketone group (168 of 274 episodes, 61.3%) (P < 0.001). The incidence of hospitalization/emergency assessment was significantly lower in the blood ketone group (38/100 patient-years) compared with the urine ketone group (75/100 patient-years) (P = 0.05). CONCLUSIONS: Blood ketone monitoring during sick days appears acceptable to and preferred by young people with Type 1 diabetes. Routine implementation of blood 3-OHB monitoring for the management of sick days and impending DKA can potentially reduce hospitalization/emergency assessment compared with urine ketone testing and offers potential cost savings.  相似文献   
7.
The high incidence and profile of ras gene mutations reported in spontaneous and chemically induced liver tumours of the B6C3F1 mouse provides a potential means of determining in vivo genotoxicity and its relevance to carcinogenicity. We analysed spontaneous and chemically induced [with 4-amino-biphenyl (ABP), 2-acetylaminofluorene (AAF) and diethylnitrosamine (DEN)] hepatocellular tumours of the C57Bl/10J mouse for H-ras, K-ras and N-ras gene mutations to see if mutational analysis of the ras genes could be useful for such a determination in this strain. Regions of DNA spanning codons 12, 13 and 61 of the ras genes were amplified from formalin fixed liver tumour sections using the polymerase chain reaction. Mutations were detected using allele specific oligonucleotide probing and confirmed by sequencing. We have found that there are few ras mutations in either spontaneous or chemically induced liver tumours in the C57Bl/10J mouse. Out of 25 spontaneous tumours two contained an A to T transversion and one contained an A to G transition in base 2 of H-ras codon 61 and two contained a G to A transition in base 2 of K-ras codon 13 (the K-ras mutations were only faintly detectable and may be present in a subpopulation of the tumour cells). In the case of the 18 ABP induced tumours one contained a C to A transversion in base 1 of H-ras codon 61, and one contained an A to T transversion in base 2 of H-ras codon 61 and one contained a G to C transversion in base 1 of K-ras codon 13. One C to A transversion in base 1 of H-ras codon 61 was detected out of eight AAF induced tumours. Of the 25 DEN induced tumours, one contained an A to G transition and one contained an A to C transversion in base 2 of H-ras codon 61. The data indicate that at least in hepatocellular tumours of the C57Bl/10J strain and using chronic dosing regimes the ras genes do not represent markers for in vivo genotoxic activity.  相似文献   
8.
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
9.
The L4 filtration membrane was used at our laboratory on 30 semen specimens (19 from suspected subfertile patients and 11 from fertile donors) to assess changes in semen quality after routine sperm washing and swim up versus filtration through the L4 membrane. Of these 30 samples 17 (11 suspected subfertile patients and 6 fertile donors) were chosen to evaluate differences in sperm fertilizing ability between the 2 sperm preparation methods. Liquified specimens were analyzed on a Cell Soft semen analyzer. Semen specimens were divided equally, and 1 aliquot was processed by sperm washing and the swim up technique and the other by filtration. In all subjects the results of semen analysis and the hamster-egg penetration test showed significant improvement in sperm quality and fertilizing ability after filtration through the L4 membrane. Sperm motility was 58% after the swim up technique compared to 79% after filtration (p less than 0.0001) and velocity was 47 mu. per second after the swim up method compared to 52 mu. per second after filtration (p less than 0.048). Penetration rate and penetration index also showed a significant increase after filtration over values for the swim up method. Our results demonstrate that sperm filtration through the L4 membrane provides results superior to those of the traditional swim up technique. Due to significant savings in time associated with its use the L4 membrane can be used during sperm processing for intrauterine insemination and in vitro fertilization procedures.  相似文献   
10.
菊叶三七生物碱成分的研究   总被引:8,自引:0,他引:8  
从菊科蒂叶三七植物中分离出六个生物碱,对其中四个进行了鉴定。光谱数据证明:生物碱Ⅰ和Ⅱ分别为已知的千里光碱(senecionine,Ⅰ)和千里光菲灵碱(seneciphylline,Ⅱ),生物碱Ⅲ和Ⅳ为新成分,分别命名为菊三七碱甲(sineciphyllinine,Ⅲ)和菊三七碱乙[(E)-seneciphylline,Ⅳ]。  相似文献   
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