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61.
OBJECTIVE: To address the issue as to how best to perform statistical MUNE, we applied two different approaches and compared results in healthy subjects and ALS patients. METHODS: Twelve normal subjects (women 8, mean age 52years) and 11 ALS patients (women 4, mean age 54years) underwent two consecutive MUNE studies, which differed in terms of setting and modifying the recording window. These are referred to as the 'expansion' and 'narrowing' methods, respectively. Size-weighted average (Av) SMUP and MUNE values were obtained using the two methods, and compared in control and patient groups. RESULTS: Expansion method-derived Av SMUP sizes and MUNE values differed only slightly from those obtained using the narrowing method in healthy subjects, whereas the narrowing method resulted in significantly larger Av SMUP sizes and smaller MUNE values than the expansion method in ALS patients (Wilcoxon signed ranks test, p=0.003). The sizes of tested areas (mean+/-SD) were significantly larger for the narrowing method than the expansion method in both subject groups with much greater difference in ALS patients; 9.6+/-3.1% vs. 7.9+/-1.7% in healthy subjects and 16.1+/-5.1% vs. 11.2+/-3.0% in ALS patients (Student t-test, p<0.01). CONCLUSIONS: The present study shows, unlike that found in normal subjects, that the results of statistical MUNE in ALS patients are heavily dependent on the approach used to set and modify recording windows. SIGNIFICANCE: The expansion method using a 10%-sized window is likely to suffer from systemic errors due to the ceiling effect and the sampling of artifactually small motor units in ALS patients. The authors recommend that the narrowing method be considered as an alternative that avoids these problems.  相似文献   
62.
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.  相似文献   
63.
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   
64.
Comparison of alfentanil with fentanyl for outpatient anesthesia   总被引:5,自引:0,他引:5  
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65.
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   
66.
We considered performing living donor liver transplantation (LDLT) in a larger-size recipient. When the recipient was large-sized, or when the donor liver was severely steatotic or had a right-to-left volume discrepancy. We devised dual living donor liver transplantation (DLDLT) to make up for graft size insufficiency and to secure the donor's safety. However, portal vein thrombosis (PVT) presented a challenge for DLDLT because of the need for intact right and left portal veins for the implantation of both liver grafts. Our 52-year-old male patient with hepatitis B cirrhosis had suffered from repeated esophageal and gastric variceal bleeding and underwent 2 trials of a transjugular intrahepatic portosystemic shunt (TIPS). He developed TIPS occlusion and PVT involving the area just above the spleno-mesenteric confluence to the right and left PV. Also, the right PV orifice was destructed and difficult to isolate because of severe periportal inflammation and neointima growth in the TIPS mesh. The patient's two sons were inadequate for donation because of right-to-left volume discrepancy. Therefore, DLDLT using 2 left lobes was necessary to compensate for graft-size insufficiency and to secure donor safety, and we substituted an intact umbilical portion of recipient's left PV for the destroyed right PV. The patient recovered well, and liver function has been normal for more than a year. In conclusion, the umbilical portion of recipient's left PV can be a useful vascular substitute for the reconstruction of a thrombosed main portal branch in DLDLT.  相似文献   
67.
BACKGROUND/AIMS: Carcinogenesis is characterized by the abnormal regulation of cell cycle. The abnormal expression of the regulators of cell cycle may be related to the prognosis. Since the clinical significance of the expression of the three proteins in colorectal carcinomas is still controversial, we evaluated the prognostic value of the expression of cyclin E, p27 and mutant p53 in stage II colorectal cancer. METHODS: The expression levels of cyclin E, p27 and mutant p53 proteins in 41 patients with stage II colorectal carcinomas were analyzed by immunohistochemistry. RESULTS: In the univariate analysis, the level of CEA at diagnosis was associated with disease relapse. In the multivariate analysis, the clinicopathological variables such as age, gender, site of primary tumor, tumor size, state of tumor differentiation and preoperative plasma CEA level were not associated with disease relapse. When Kaplan-Meier survival curves were constructed to determine the prognosis, cyclin E, p27 and mutant p53 expressions did not predict poor prognosis. CONCLUSIONS: Our results suggested that the expression of cyclin E, p27 and mutant p53 proteins did not predict the clinical outcome in the stage II colorectal carcinomas.  相似文献   
68.
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   
69.
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   
70.
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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