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We report the results of an expanded trial of 5-fluorouracil (FUra) combined with high-dose folinic acid for treatment of patients with advanced colorectal or gastric adenocarcinoma. In each treatment course, the patients received both FUra (340-400 mg/m2/day by iv infusion over 15 minutes) and folinic acid (200 mg/m2/day by iv bolus) for 5 consecutive days, with a 21-day interval between courses. Eighty-six patients with colorectal carcinoma were evaluated. The combined complete response (CR) and partial response (PR) rates were 39% for 54 patients who did not receive prior chemotherapy and 22% for 32 patients who had previously received chemotherapy. Four patients who were previously resistant to FUra attained objective responses. The median time to disease progression for the 28 responders was 10 months. The median survival time of responders was 19.5 months, and the probability of their being alive at 2 years was 40%. Of 27 patients with gastric adenocarcinoma, 13 (48%) responded to therapy. Their median time to disease progression was 5.5 months. The median survival time of responders was 11 months, and their probability of being alive at 15 months was 30%. Toxicity was within acceptable limits. Toxic effects included stomatitis, diarrhea, conjunctivitis, skin rash, and mild myeloid hypoplasia. In a separate study, plasma concentrations of L-folates above 10(-5) M were achieved after a rapid single iv injection of 200 mg/m2 of folinic acid.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Regional cerebral blood flow (rCBF) changes in cortical motor areas were measured during a movement of the dominant right hand in 15 patients with Parkinson's disease deprived of their usual levodopa treatment, in 11 patients with Parkinson's disease undergoing long-term treatment with levodopa, and in 15 normal volunteers. The supplementary motor areas were significantly activated in the normal subjects and in the patients receiving levodopa but not in the patients deprived of levodopa. The contralateral primary sensory motor area was significantly activated in all three groups. The ipsilateral primary sensory motor cortex was not activated in the normal subjects and the non-treated patients but was in the patients treated with levodopa. It is concluded that the supplementary motor area hypoactivation which is observed in akinetic non-treated patients with Parkinson's disease is not present in patients undergoing long-term treatment with levodopa. This result suggests that (a) levodopa improves the functional activity of supplementary motor areas in Parkinson's disease and (b) there is no pharmacological tolerance to this effect. The ipsilateral primary motor cortex activation observed in the patients treated with levodopa could be related to levodopa-induced abnormal involuntary movements.  相似文献   
4.
Several authors have discussed an alteration of adrenergic receptivity in arterial hypertension. De Champlain (Hypertension 1990; 8: S77-S85) suggested that postsynaptic alpha 1-adrenergic functions became dominant while beta-adrenergic functions are attenuated in arterial hypertension. However, the status of presynaptic alpha 2-adrenoceptors remains unknown. The present study investigates presynaptic alpha 2-adrenoceptors in hypertension through the measurement of plasma levels of noradrenaline after administration of yohimbine, an alpha 2-adrenoceptor antagonist, in essential hypertension. Yohimbine (0.2 mg/kg per os) induced a 73% increase of plasma levels of noradrenaline in hypertensive patients (n = 12) and a 178% one in normotensive subjects (n = 6, p < 0.05). A similar significant difference was found in experimental neurogenic hypertension observed in awake dogs 3 weeks after sinoaortic denervation: the increase in plasma concentrations of noradrenaline after yohimbine (0.5 mg/kg i.v.) was +279% in hypertensive versus +642% in normotensive dogs (p < 0.05). The results show that the magnitude of the yohimbine-induced sympathetic activation is lower in hypertensives than in normotensives. They suggest the existence of a presynaptic alpha 2-adrenoceptor desensitization in arterial hypertension. The abnormality of this presynaptic inhibitory mechanism can increase the sympathetic tone and help to develop and maintain arterial hypertension.  相似文献   
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Background: Blockade of parietal nociceptive afferents by the use of continuous wound infiltration with local anesthetics may be beneficial in a multimodal approach to postoperative pain management after major surgery. The role of continuous preperitoneal infusion of ropivacaine for pain relief and postoperative recovery after open colorectal resections was evaluated in a randomized, double-blinded, placebo-controlled trial.

Methods: After obtaining written informed consents, a multiholed wound catheter was placed by the surgeon in the preperitoneal space at the end of surgery in patients scheduled to undergo elective open colorectal resection by midline incision. They were thereafter randomly assigned to receive through the catheter either 0.2% ropivacaine (10-ml bolus followed by an infusion of 10 ml/h during 48 h) or the same protocol with 0.9% NaCl. In addition, all patients received patient-controlled intravenous morphine analgesia.

Results: Twenty-one patients were evaluated in each group. Compared with preperitoneal saline, ropivacaine infusion reduced morphine consumption during the first 72 h and improved pain relief at rest during 12 h and while coughing during 48 h. Sleep quality was also better during the first two postoperative nights. Time to recovery of bowel function (74 +/- 19 vs. 105 +/- 54 h; P = 0.02) and duration of hospital stay (115 +/- 25 vs. 147 +/- 53 h; P = 0.02) were significantly reduced in the ropivacaine group. Ropivacaine plasma concentrations remained below the level of toxicity. No side effects were observed.  相似文献   

7.
We describe a case of cutaneous malignant melanoma metastatic to the iris and the angle 31 months after excision of the primary tumor in a 37-year-old caucasian female patient. The patient who had numerous metastases (lung, liver, cerebrum, skin) suffered from secondary glaucoma and died 5 months after the discovery of the intraocular metastases. The glaucoma was treated with medications and cyclocryotherapy. There was no response of the iris metastases to cyclical combined chemotherapy.  相似文献   
8.
This article discusses issues to be considered by nurse researchers when groups should be used as the unit of randomization. Advantages and disadvantages are presented, with statistical calculations needed to determine the effective sample size. Examples of these concepts are presented using data from the Black Cosmetologists Promoting Health Program. Different hypothetical scenarios and their impact on sample size are also presented. Given the complexity of calculating the sample size when using groups as the unit of randomization, it is advantageous for researchers to work closely with statisticians when designing and implementing studies that anticipate the use of groups as the unit of randomization.  相似文献   
9.
Pharmacological and genetic studies suggest the importance of the dopaminergic, serotonergic, and noradrenergic systems in the pathogenesis of attention deficit hyperactivity disorder (ADHD). Monoamine oxidases A and B (MAO-A and MAO-B) degrade biogenic amines such as dopamine and serotonin and thereby control the levels of these neurotransmitters in the central nervous system. We examined four polymorphisms in the MAO-A gene (30 bp promoter VNTR, CA microsatellite in intron 2, 941G/T SNP in exon 8, and A/G SNP in intron 12) as well as two markers in the MAO-B gene (CA microsatellite in intron 2 and T/C SNP in intron 13) for association with ADHD in an Irish sample of 179 nuclear families. TDT analysis of the examined MAO-A markers revealed a significant association of the more active MAO-A 941G allele with the disorder (chi2 = 5.1, P = 0.03, OR = 1.7). In addition, haplotype analysis revealed a significantly increased transmission of a haplotype consisting of the shorter allele of the promoter VNTR (allele 1), the 6-repeat allele of the CA microsatellite and the G-allele of the 941G/T SNP (famhap global statistic 34.54, P = 0.01) to ADHD cases. No significant distortion in the number of transmitted alleles was observed between the two examined MAO-B polymorphisms and ADHD. These findings suggest the importance of the 941G/T MAO-A polymorphism in the development of ADHD at least in the Irish population.  相似文献   
10.
The renin-angiotensin system (RAS) is essential for blood pressure control and water-electrolyte balance. Until the discovery of the renin receptor, renin was believed to be mainly a circulating enzyme with a unique function, the cleavage of angiotensinogen. We report a unique mutation in the renin receptor gene (ATP6AP2) present in patients with X-linked mental retardation and epilepsy (OMIM no. 300423), but absent in 1200 control X-chromosomes. A silent mutation (c.321C>T, p.D107D) residing in a putative exonic splicing enhancer site resulted in inefficient inclusion of exon 4 in 50% of renin receptor mRNA, as demonstrated by quantitative RT-PCR. Analysis of membrane associated-receptor molecular forms showed the presence of full-length and truncated proteins in the patient. Functional analysis demonstrated that the mutated receptor could bind renin and increase renin catalytic activity, similar to the wild-type receptor, but resulted in a modest and reproducible impairment of ERK1/2 activation. Thus, our findings confirm the importance of the RAS in cognitive processes and indicate a novel specific role for the renin receptor in cognitive functions and brain development.  相似文献   
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