Effect of meal on the physiological and physicochemical actions of potassium citrate

The effect of meals on the physiological and physicochemical actions of potassium citrate was examined in 8 patients with nephrolithiasis maintained on a constant metabolic dietary regimen. Potassium citrate (20 mEq. 3 times per day), whether given with food or on an empty stomach, significantly increased urinary pH, citrate and potassium, and decreased urinary calcium and ammonium. Moreover, potassium citrate decreased urinary saturation of calcium oxalate and uric acid, although it slightly increased that of brushite. However, there was no significant difference in these measures when the drug was given with meals from the time when it was given on an empty stomach. Thus, the effect of potassium citrate on urinary risk factors is unaffected by food.     

Multiple medication: problems of the elderly patient.

Elderly persons are apt to receive multiple drugs for many diseases. Prescribers should take extra care in persons aged over 65-70 years, and especially the very old. The main problem of the elderly is the unpredictability of their response to drugs. Self-medication with both prescribed and over-the-counter drugs worsens this problem. Drug actions may be altered by impairment of the liver, kidneys and brain, or acute illness, or both. Unwanted (adverse) drug reactions often produce rapid and unduly severe illness in the old. Some antibacterial antibiotics like the sulphonamides are best avoided. Taking many drugs together promotes adverse interactions between the drugs. Drugs with a narrow therapeutic ratio, such as warfarin, digoxin, the aminoglycosides, and many antiarrhythmic drugs, cause clinical problems. Old persons respond more abruptly to drugs like benzodiazepines, opioid analgesics, and antiparkinsonian drugs. Anaesthesia given on top of psychotropic drugs may damage the central nervous system. The elderly brain is more sensitive to induction agents and short-acting intravenous anaesthetics, like alfentanil and midazolam; the elderly liver is more easily damaged by inhalational anaesthetics like halothane. The overall benefit:risk ratio should be judged for every drug in each patient. Wherever possible, drug treatment should be avoided. If drugs are given, safe drugs with broad therapeutic ratios and tissue- or receptor-specific actions are preferable. Drug doses are usually, but not always, reduced. Benefit from a drug should be assessed early. Severe unpredictable adverse reactions need immediate cessation of the drug and prompt patient support. The practitioner should frequently review the patient's continuing need for drugs.     

Partial mastectomy with axillary lymph node dissection and radiotherapy as a new treatment modality of breast cancer (I).

This is the first preliminary report among two consecutive papers. Partial mastectomy(PM), axillary lymph node dissection(AD) and radiotherapy (RT) were performed on seventeen operable breast cancer patients who had been admitted from April 1991 to March 1992 to the department of surgery, Yongdong Severance Hospital for improved cosmetic appearance and better survival rate. Of seventeen patients, 47% were T1 lesion and 76% were stage I and II. Extensive intraductal component(EIC) within or around the tumor was also analyzed. Twenty nine per cent of the patients were EIC positive. The mean number of axillary lymph nodes was 21.5 after PM with AD and 20.5 after mastectomy. For radiotherapy, 4,500 rad was delivered to the breast parenchyma and 1,600 rad of boost to the primary tumor site using the electron beam method after surgery. All patients have since been living well without any local recurrence and were satisfied with breast preservation for the one-year follow-up period. We concluded that the PM, AD and RT can be another surgical treatment modality of breast cancer. A longer follow-up data will be followed on the second paper.     

Evaluation of inotropic effect of endothelin-1 in vivo.

The vasoconstrictive peptide endothelin-1 (ET-1) has been reported to exert a very important positive inotropic effect in vitro. To assess the effect of ET-1 on myocardial contractility in vivo, we compared the effect of intracoronary infusion of 10(-8) M ET-1 (constant coronary blood flow) to that of 10(-8) M dobutamine in 8 swine. ET infusion did not produce changes in segmental shortening (control vs. drug, mean +/- SD): 33.8 +/- 14.3 vs. 30.8 +/- 12.1%, shortening velocity: 10.3 +/- 4.3 vs. 10.7 +/- 4.5 mm/s, or maximum +dP/dt: 1,691 +/- 701 vs. 1,772 +/- 773 mm Hg/s, whereas dobutamine infusion induced an important increase in these measurements; segmental shortening: 36.9 +/- 14 vs. 48.4 +/- 18.8%, shortening velocity: 10.1 +/- 2.6 vs. 14.7 +/- 4.5 mm/s, and maximum +dP/dt: 2,041 +/- 567 vs. 2,389 +/- 765 mm Hg/s (all p less than 0.05). Mean myocardial blood flow assessed by microspheres was unchanged by ET-1 despite a marked increase in coronary artery pressure (88.6 +/- 12.9 vs. 157 +/- 8.8 mm Hg, p less than 0.001). Regional infusion of ET-1 at a dose provoking extensive coronary vasoconstriction does not induce any change in regional or global myocardial function in swine.     

The haemodynamic effects of propofol and thiopentone for induction of caesarean section

Forty Chinese women for elective caesarean section received either propofol 2 mg.kg-1 or thiopentone 4 mg.kg-1 for induction of general anaesthesia. Systolic, mean and diastolic arterial pressures and heart rate were recorded non-invasively every minute for ten minutes. Post-induction arterial pressures were similar to pre-induction values with no differences between thiopentone and propofol. Following intubation, the rise in systolic arterial pressure was greater in the thiopentone group, 32.1 mmHg (SD 23.7) compared with the propofol group, 17.4 mmHg (SD 23.8), (P less than 0.05). In the thiopentone group, arterial pressures were slower in returning to baseline values. Heart rate was initially elevated in both groups to the same degree. At caesarean section, induction with propofol causes less variation in arterial pressure than thiopentone. Hypotension is probably prevented by the coincident stimulus of rapid sequence induction. Neonatal Apgar scores were similar between the two groups.     

前额迟发性小汗腺血管瘤性错构瘤

一71岁韩国男性前额出现孤立的红色斑块。该斑块出现已有1年,并缓慢增大。体检发现前额上正中线部有一轻微隆起的、1.5cm×1.5cm红色斑块。体力活动或情绪应激反应均不诱发该斑块出汗。皮损无疼痛或触痛。患者前额部无外伤史。皮损组织病理检查示外分泌腺数目增加,真皮深部和皮