固相法合成心肌兴奋肽及其类似物

用Boc-和Tos-基团分别保护氨基和侧链胍基,以1%交联度聚苯乙烯二苯甲氨基树脂为载体,用DCC固相法合成肽,HF断裂肽树脂键和去除侧链保护基团,粗产物经高效液相层析纯化,合成了心肌兴奋肽Phe-Met-Arg-Phe-NH_2及其类似物Phe-Pro-Arg-Phe-NH_2,并观察了此二种肽对大鼠血压和心率的影响。     

异一枝蒿酮酸的结构

从新疆一枝蒿(Artemisia rupestris L.)中分得一个新成分,命名为异一枝蒿酮酸(isorupestonic acid),根据光谱(IR,UV,MS.NMR),X-ray晶体衍射及CD谱分析,确定其结构及绝对构型。并经X-ray晶体衍射及CD谱分析修正了一枝蒿酮酸的绝对构型。     

Management of tooth resorption

A correct diagnosis and an understanding of the aetiology and dynamics of the processes involved in tooth resorption is critical to effective management. Tooth resorptions can be classified as: (1) trauma induced; (2) infection induced; or (3) hyperplastic invasive. Some transient trauma induced resorptions require no treatment but must be carefully monitored to check that there are no complicating issues such as infection. In cases of trauma induced replacement resorption, a multidisciplinary approach is usually necessary to ensure an optimal long-term solution. Infection induced tooth resorptions require the removal of the invading micro-organisms by endodontic therapy including intra-canal medication which can also facilitate repair of the resorbed tooth structure. The hyperplastic invasive tooth resorptions pose considerable challenges in management due to the complexity and aggressive nature of the resorptive process. With careful case selection and complete inactivation of resorptive tissue successful management can be achieved.     

Randomised comparison of ondansetron and metoclopramide plus dexamethasone for chemotherapy induced emesis

The serotonin (5HT3) antagonist ondansetron was compared in a randomised study with metoclopramide and dexamethasone for the prevention of chemotherapy induced emesis. Thirty children aged 1-15 years with acute lymphoblastic leukaemia received 'intensification modules' according to the MRC United Kingdom acute lymphoblastic leukaemia regimen UKALL XI. This contains the moderately emetogenic drugs daunorubicin, etoposide, and cytarabine. Fifteen children received an intravenous loading dose of ondansetron followed by intravenous or oral doses 12 hourly for five days. Fifteen children received intravenous metoclopramide every six hours for three days with a loading dose of dexamethasone, repeated every eight hours for three days intravenously or orally. Efficacy was assessed by a diary card documenting the incidence of nausea, retching, or vomiting. In the 24 hour period after starting chemotherapy, ondansetron was more effective, with a complete or major response rate of 93%, compared with 33% using metoclopramide/dexamethasone.     

争光霉素A6和它在争光霉素复合物的地位

争光霉素A₅已鉴别为Bleomycin A₆,在争光霉素复合物中所占比例一般在10%左右,在某些批样中可高达15%以上。文献报告Bleomycin A₆在天然产的Bleomyein复合物中只有痕量。通过向发酵培养基中加入特定组分的末端胺可大大提高其特定组分在复合物中的含量比而其它组分的产生则不同程度地被抑制。但Bleomyein A₆例外,即使向培养基中加入其末端胺精胺(0.3mg/ml),在所产生的复合物中大大增多的组分是Bleomyein A₆,而Bleomycin A₆仍只有痕量。这表明争光霉素产生菌有和Bleomycin产生菌明显不同的特点。     

What is the optimum A-V interval in D.D.D. pacing?

One of the programmable parameters in recent pacemakers is atrio-ventricular interval. To find out the optimum A-V interval studies were done in 14 patients. Multigated radionuclide scans were used to measure the left ventricular function, at a resting heart rate of 70/minute. Seven patients had poor left ventricles (ejection fraction less than 50%). Left ventricular ejection fraction, relative cardiac output and end diastolic counts were highest at 250 M. Sec. interval compared to 150. Ejection rates and end systolic counts were not related to A-V interval. Relative cardiac output was 27% higher in poor ventricles at 250 delay than 150. This observation was not significant in normal hearts. Optimum P-R interval is 250 M. Sec. for maximum left ventricular function.     

The safety and efficacy of gi endoscopy in patients with acute-leukemia - a review of 27 cases

In the course of aggressive treatment for acute leukemia, the ensuing pancytopenia and intensive medical support may be accompanied by severe gastrointestinal (GI) complications. Therefore, to assess the safety and efficacy of GI endoscopy as a means of diagnosis, we analyzed the records of 16 patients undergoing 27 endoscopies a mean (+/-S.D.) of 18.4 +/- 11.9 days post chemotherapy. There were 6 procedures performed in patients with acute lymphocytic, 18 with acute myelogenous, including 3 with acute promyelocytic and 3 with blastic phase chronic myelogenous leukemia. 10/27 procedures were performed in patients with less than 1000 WBC/mm3 and 19/27 had less than 100,000 platelets. 15 patients had 25 upper endoscopies done for: bleeding (twenty-one), abdominal pain (two), and persistent vomiting (two). The principal bleeding sources were: esophagitis (eleven), Mallory Weiss tear (one), gastritis (three), gastric ulcer (one), duodenal ulcer (five). In the non-bleeding cases 2 exams were normal and the others had gastritis (one) and esophagitis (one). 15/25 procedures (64%) resulted in new diagnosis and 20/25 (80%) in additional therapies. 47% of patients undergoing upper GI endoscopy received specific new therapies as a result of that procedure. Nd: YAG laser photocoagulation was effective in stopping bleeding lesions in 4/6 cases. 10/12 bleeding patients had persistent or recurrent bleeding and 2 died from bleeding. None had surgery. Two patients underwent colonoscopy, both for colonic distention. One patient, who had been recently treated for Cl. difficile had submucosal petechiae. The other had non-specific colitis. No biopsies were done and both cases were successfully decompressed..No complications occurred from any GI endoscopy. We conclude that GI endoscopy can be safely performed in patients with acute leukemia, resulting in specific diagnoses and therapies. Esophagitis is a principal cause of GI bleeding in these patients. The role of therapeutic endoscopy in controlling bleeding is promising but requires further evaluation.