缬昔洛韦的合成

目的;对缬昔洛韦的合成进行了研究。方法：以阿昔洛韦和Ｎ－苄氧羰基－Ｌ－缬氨酸为原料,经酰化,催化氢解反应得到了新型抗疱疹毒药物缬昔洛韦。结果;本品的元素分析,红外,质谱及核磁共振图谱数据与文献报道一致,总收率为４５．２％,结论;采用此法合成缬昔洛韦是可行的,适合于工业生产。     

Dietary energy restriction does not inhibit pancreatic carcinogenesis by N-nitrosobis-2-(oxopropyl)amine in the Syrian hamster

Dietary energy restriction was previously shown to be effective in preventing a wide range of experimentally induced cancers. Studies were conducted to assess the influence on pancreatic carcinogenesis of dietary energy restrictions (reduced fat and carbohydrate) of 10%, 20% or 40% in comparison with control in Syrian hamsters treated with N- nitrosobis(2-oxopropyl)amine (BOP). Two carcinogenesis studies were conducted. One used a single treatment with 20 mg BOP/kg body weight and followed hamsters for 102 weeks following treatment, and the other used three weekly treatments of 20 mg BOP/kg body weight and followed hamsters for 45 weeks after treatment. Hamsters were fed control or energy restricted diet beginning the week following the last BOP treatment. Pancreatic carcinomas were induced in 9-18% of the hamsters in the first experiment and in 59-66% of the animals in the second. Dietary energy restriction did not influence carcinoma incidence in either study, and in the second experiment the multiplicity of tumors was higher in the 40% energy restriction (ER) group than in control hamsters. Plasma corticosterone was suppressed by BOP treatment, particularly in the 20% and 40% ER hamsters in the second experiment, and diet or BOP treatment did not significantly alter plasma cortisol. Pancreatic protein kinase Czeta measured by Western blot was highest in the cytosol and particulate fractions of the 40% ER hamsters in the first experiment. These results indicate that dietary energy restriction is not effective in the prevention of BOP induced pancreatic carcinogenesis in the Syrian hamster.      

Des-gamma-carboxy prothrombin is a promising biomarker of hepatocellular carcinoma and a predictor of complications in patients with chronic liver diseases

<正>To the Editor: Although des-gamma-carboxy prothrombin(DCP) is considered a complementary biomarker to alpha-fetoprotein(AFP) in the diagnosis of hepatocellular carcinoma(HCC), its cut-off value has not been recommended in any guideline. This study aimed to explore the diagnostic efficacy of DCP on HCC.     

COVERT HYPOTHYROIDISM WITH WEIGHT LOSS AND ATRIAL FIBRILLATION

SUMMARY Hypothyroidism may present with weight gain and/or cardiovascular manifestations such as bradycardia or cardiac failure, but has not previously been documented as presenting with atrial fibrillation and weight loss. Our case highlights the importance of thyroid function tests in heart failure and emphasises the importance of regular follow-up after irradiation to the thyroid.     

Contrast medium precipitation during abdominal CT

Abdominal computed tomography (CT) scans of 55 patients who had ingested Gastrografin (meglumine diatrizoate and diatrizoate sodium) diluted to 2% with tap water and flavored with a commercial fruit juice base were reviewed. Twenty patients (36%) demonstrated intraluminal precipitation of Gastrografin shown by focal areas of markedly increased attenuation within the gastric lumen or trapped within gastric folds. Beam-hardening artifact produced by precipitation was observed, which limited the diagnostic value of some examinations. In vitro CT scans of the same Gastrografin solution titrated with hydrochloric acid or sodium hydroxide showed that by raising the pH of the solution, precipitation was virtually eliminated. Fifty-one CT scans of the abdomen using a buffered Gastrografin solution demonstrated precipitation in only five patients. Properly buffered dilute oral Gastrografin solutions should significantly decrease the prevalence of precipitation during abdominal CT examinations.     

颈动脉内膜剥脱术后即期脑中风的病因、影响因素及治疗（摘要）

对２９１例颈动脉内膜剥脱术后患者进行随访研究，１例术后即期死亡；２２例（６．３％）在术后发生脑中风，１７例为中度中风，５例为严重中风，即期中风的病因包括：１４例手术部位颈动脉血栓形成（１４／２２，６４％），４例术中或术后即期脑栓塞，２例阻断颈动脉所致脑缺血，１例脑出血，１例原因不明，此外讨论了术后中风的危险因素和处理方法。     

Experiences of the first 493 unrelated marrow donors in the National Marrow Donor Program

More than 410,000 people participated in the National Marrow Donor Program (NMDP) as of October 1, 1991, and more than 850 volunteers had donated marrow. While the incidence of serious morbidity as a result of bone marrow donation is rare, the incidence of lesser complications and the long-term consequences of marrow donation are not known. To determine the incidence of donor complications and measure the recovery time of volunteer, unrelated marrow donors, we analyzed the results of surveys of the first 493 persons who donated marrow through the NMDP. The marrows were collected at 42 centers. The median age of the donors was 37.9 years (range 19.1 to 55.6 years). The median volume of marrow collected was 1,050 mL (range 180 to 2,983 mL). Autologous red blood cells were transfused to 89.8% (439) of donors but only 0.6% (3) of donors received allogeneic blood. Acute complications related to the collection procedure occurred in 5.9% of donors; but a serious complication, apnea during anesthesia, occurred in only one donor. When donors were questioned approximately 2 days following discharge from their hospitalization, most donors described symptoms related to the collection; 74.8% experienced tiredness, 67.8% experienced pain at the marrow collection site, and 51.6% of the donors experienced low back pain. Donors were surveyed repeatedly until they felt that they had recovered completely. Mean recovery time was 15.8 days; however, 42 (10%) donors felt that it took them > or = 30 days to recover fully. The duration of the marrow collection procedure and duration of anesthesia both positively correlated with donor pain and/or fatigue following the collection; but the duration of the collection procedure had the highest correlation with post-collection pain and fatigue. The volume of marrow collected per unit of donor weight was more weakly correlated with donor pain and/or fatigue than the anesthesia and collection times. When multivariate analysis was used to analyze the correlation between donor recovery time and these variables, only the duration of the collection was found to correlate significantly with donor recovery time (P = .001). This analysis demonstrates that marrow donation is well tolerated with few complications. To decrease further the incidence of donor discomfort and recovery time following donation, the duration of the collection procedure, and probably the duration of anesthesia, and the volume of marrow collected, should be kept to a minimum.