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21.
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.  相似文献   
22.
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.  相似文献   
23.
Needle electromyography (EMG) and determining the motor evoked potential (MEP) of the genioglossus (tongue) are difficult to perform in evaluation of the craniobulbar region in patients with amyotrophic lateral sclerosis (ALS). Needle EMG and MEP determination in the upper trapezius were carried out in 17 consecutive ALS patients. The needle EMG parameters recorded included abnormal spontaneous activity and motor unit action potential morphology. An upper motor neuron lesion was presumed when either response to cortical stimulation was absent, or the central conduction time was delayed (>mean + 2 SD). Of the 12 patients with limb-onset ALS, using needle EMG, 11 were found to have abnormalities in the upper trapezius, and only five in the tongue. Three of the six patients with isolated limb involvement had abnormal MEP findings. In conclusion, electrophysiological studies of the upper trapezius are useful in ALS patients without bulbar symptoms.  相似文献   
24.
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.  相似文献   
25.
A 25-year-old female has had brown to erythematous telangiectatic patches and grouped papules on her face, neck, arm, and trunk since childhood following B.C.G. vaccination. Histopathologically, the lesions consisted of hyperkeratosis, slight acanthosis, tuberculoid granulomas with some Langerhans type giant cells in the mid-dermis. Although various forms of cutaneous tuberculosis after B.C.G. vaccination have been reported, it was difficult for us to assign the patient's skin lesion to any specific disease entity. Remission of her cutaneous lesions occurred clinically and histopathologically after treatment with isoniazid and rifampin.  相似文献   
26.
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.  相似文献   
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28.
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  相似文献   
29.
Although adenocarcinoma is a well known complication of chronic inflammatory bowel disease, primary gastrointestinal lymphoma occurring in Crohn's disease is rare. A 40-year-old man with 10 year-history of Crohn's disease had multiple longitudinal ulcerative lesions on descending colon in follow-up colonoscopic examination. Microscopic examination of proximal descending colon revealed peripheral T cell lymphoma and other site of the descending colon was consistent with Crohn's disease. The patient reached complete remission of malignant lymphoma after three cycles of combined chemotherapy. He has been well for 10 months with sulfasalazine maintenance therapy but was admitted to the hospital due to spontaneous bowel perforation of ascending colon. Right hemicolectomy was done, but the patient died of post-surgical recurrent mesenteric abscess and sepsis. To the best of our knowledge, this is the first case of Non-Hodgkin's lymphoma complicating Crohn's disease in Korea which was confirmed by immunohistochemical studies.  相似文献   
30.
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