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81.
Summary The interaction of locally perfused cholecystokinin-8 (sulphated) with systemically administered apomorphine was studied on the release of dopamine and its metabolites using microdialysis in the neostriatum of the halothane-anaesthetized male rat. Dialysate levels of dopamine, 3,4-dihydroxyphenylacetic acid and homovanillic acid were assayed by high performance liquid chromatography in combination with electrochemical detection. Perfusion with cholecystokinin-8 (100 M but not 1 M or 10 nM) increased the dialysate levels of dopamine without affecting those of DOPAC or HVA. At low concentrations (1 M and 10 nM but not 1 nM), cholecystokinin-8 counteracted the inhibitory effect of apomorphine (0.05 mg/kg, s. c.) on dopamine release. This counteraction was antagonized by perfusion with the cholecystokinin-8 antagonist proglumide (3 M). At this concentration, proglumide perfused alone was without effect on basal or apomorphine-reduced levels of dopamine. The results indicate a facilitatory effect of cholecystokinin-8 on dopamine release in rat neostriatum only at high concentrations. At lower concentrations, cholecystokinin-8 appears to modulate dopamine release by an inhibitory effect on dopamine autoreceptors possibly involving an intramembrane interaction between presynaptic cholecystokinin-8 receptors and dopamine autoreceptors. Send offprint requests to K. Fuxe at the above address  相似文献   
82.
Crossed aphasia. An update   总被引:2,自引:0,他引:2  
The aim of this article is to present an update of a rare but interesting problem: crossed aphasia. This term indicates the presence of aphasia after unilateral cerebral lesion of the hemisphere ipsilateral to the patient's dominant hand. We report two cases, review the most relevant literature, and analyze clinical, neuroanatomical, and neurophysiological aspects, taking in consideration the various interpretations proposed to explain this unusual language disorder.  相似文献   
83.
Anastomosis   总被引:6,自引:1,他引:5  
Esophageal anastomosis is still associated with a high rate of complications even though they have decreased considerably in recent years. Anastomotic leaks are more frequent in the neck than in the chest, and related mortality rate is not different. The leakage incidence does not depend on suture materials or on technical modalities used to perform the anastomosis. In fact, there is no difference between the leakage rate when comparing manual and mechanical anastomoses. The leak incidence after both mechanical and manual anastomoses is much higher in collective reviews than in reports coming from leading centers. Frequent esophageal surgeons can learn from their previous experience and therefore avoid technical errors, whereas casual esophageal surgeons do not have this opportunity. Performing an esophageal anastomosis is a technical matter, and suture healing is independent of the patient's biologic situation. Anastomotic fibrotic stricutures are frequent after both manual and mechanical anastomoses, and most can be avoided by meticulous suturing technique.
Resumen La anastomosis esofágica todavía se asocia con una elevada incidencia de complicaciones, a pesar de que éstas han descendido en forma considerable en los últimos años. Las fugas anastomóticas son más frecuentes en el cuello que en el tórax y las tasas de mortalidad no son diferentes. La rata de fuga anastomótica no depende de los materiales de sutura o de las modalidades técnicas que se utilicen para realizar la anastomosis. De hecho no hay diferencia en cuanto a la rata de fugas entre las anastomosis manuales y las mecánicas. La incidencia de fuga, tanto en las manuales como en las mecánicas, es bastante más alta en las revisiones colectivas que en los reportes emanados de los centros médicos de mayor importancia. Los cirujanos especialistas en esófago tienen la posibilidad de aprender de sus experiencias previas y con ello evitar los errores técnicos, en tanto que aquellos cirujanos ocasionales no la poseen. La realización de una anastomosis esofágica es un asunto técnico y la cicatrización de la sutura es independiente de la condición biológica del paciente. Las estrecheces fibróticas de las anastomosis son frecuentes luego de las anastomosis manuales, al igual que luego de las anastomosis mecánicas y la mayoría puede ser evitada mediante una técnica meticulosa.

Résumé Le taux de complications des anastomoses oesophagiennes, même s'il y en a moins ces dernières années, reste toujours élevé. La fréquence de fistules est plus grande quand l'anastomose est faite au cou par rapport au thorax, mais la mortalité n'en est pas très différente. L'incidence de fistules ne dépend ni du matériau de suture ni des modalités d'anastomoses utilisées. Il n'y a aucune différence lorsque les anastomoses manuelles sont comparées aux anastomoses méchaniques: L'incidence des fistules, que ce soit à la main ou à la machine est plus élevée dans les séries collectives par rapport à celle des centres spécialisés. Les chirurgiens qui font des anastomoses de façon régulière ont la possibilité de profiter de leur expérience et ainsi d'éviter les erreurs techniques, alors que le chirurgien occasionnel de l'oesophage n'a pas cette possibilité. L'anastomose oesophagienne est techniquement difficile et la cicatrisation est indépendante de l'état clinique et biologique du patient. Les sténoses fibreuses sont aussi fréquentes après les anastomoses manuelles qu'après les anastomoses méchaniques, mais la plupart peuvent être évitées par une technique méticuleuse.
  相似文献   
84.
Two cases of intradural cavernous angioma of the cauda equina are reported, one of which presented with symptoms of subarachnoid hemorrhage. The clinical and therapeutic aspects of intradural angiomas, in particular those of the cauda equina, are discussed.  相似文献   
85.
PURPOSE: To determine the "real world" cost of sevoflurane compared with isoflurane in balanced general anesthesia for daycare arthroscopic menisectomy, we prospectively investigated perioperative drug requirement and expense as well as recovery time. METHODS: Following intravenous induction, 40 consenting adult patients randomly received either sevoflurane- or isoflurane-based anesthesia with a standardized gas inflow rate of 3 l x min. Recovery was assessed in the postanesthetic recovery room (PARR) in a double-blind manner at 15 min intervals using the Aldrete scoring system until patients met discharge criteria. RESULTS: Patient demographics, anesthetic duration, volatile potency and adjunct drug requirements were similar in the two groups. Total perioperative drug cost per patient was CAN$38.10+/-10.13 (mean +/- SD) for the sevoflurane group and $23.87+/-6.59 for the isoflurane group (P<0.01). Although the nonvolatile drug cost was comparable between the two groups, the volatile drug cost per patient was $19.40+/-8.80 for sevoflurane and $4.50+/-1.90 for isoflurane (P<0.01). This four-fold sevoflurane-to-isoflurane cost difference was the product of two ratios, both based on the volume of liquid anesthetic: the ratio of consumption, 2.1; and the ratio of institutional price, 2.1. Intraoperative hemodynamic response, time until discharge from the PARR and incidences of postoperative nausea and vomiting did not significantly differ between the two groups. CONCLUSIONS: When used to maintain equipotent balanced general anesthesia for daycare arthroscopic menisectomy, volatile consumption and cost were greater for sevoflurane compared with isoflurane. Nonvolatile perioperative drug cost and recovery times were similar, however, in the two groups.  相似文献   
86.
Gamma-hydroxybutyric acid (GHB) is an emerging drug for alcoholism therapy. We present a case of GHB withdrawal syndrome secondary to GHB addiction during alcoholism treatment. A complete disappearance of drug withdrawal syndrome was achieved with oral diazepam and the symptoms resolved without sequelae. GHB has been used for alcoholism therapy for only a few years now, but the trend is increasing, and other cases similar to this one are foreseeable. This risk could be higher in some countries in which GHB use is increasing not for alcoholism therapy, but for its euphoric and anabolic effects. The present experience indicates that administration of benzodiazepines would seem to be sufficient to achieve total regression of the withdrawal syndrome in a short time, at least if recognized early.  相似文献   
87.
A case of medullary thyroid carcinoma is reported. Moreover, the main peculiarity, the correct diagnostic approach and the therapeutic indication of this rare pathology are described.  相似文献   
88.
89.
Summary The relationship between tumor proliferative activity and response to first-line chemotherapy and survival was investigated in 76 advanced breast cancer patients. Proliferative activity was determined by means of Ki-67 immunohistologic staining on primary tumors (55 patients) or at the relapse site (21 patients), and was classified as low ( 25% of stained cells) or high (> 25% of stained cells). The usual WHO response criteria were used. The median duration of follow-up was 18 months (range 3–58).Forty-seven patients (62%) had tumors with low, and 29 (38%) had tumors with a high rate of proliferative activity. The two groups were well balanced in terms of important variables such as disease-free survival, performance status, age, menopausal status, and the type of first-line chemotherapy (anthracycline-based regimens versus cyclophosphamide-methotrexate-5-fluorouracil). The estrogen receptor (ER) content, measured by means of immunohistochemical assay, was markedly different in the two groups, with 27/47 tumors with low proliferative activity (57%) and 6/29 with high-proliferative activity (21%) being ER positive ( 45% of stained cells) (p = 0.003). Moreover, a significant difference in the metastatic pattern was also evident, with a higher incidence of bone and a lower incidence of soft tissue metastases in the group of patients with tumors with low proliferative activity (p = 0.004). Overall, 10/47 responses (21%: PR = 7, and CR = 3) were observed in the group with a low rate of proliferative activity, versus 14/29 (48%: PR = 9, and CR = 5) in the group with highly proliferative tumors, the difference being statistically significant (p = 0.03). When a multivariate analy-sis was performed, the only factor that retained independent prognostic significance was the predominant site of disease, particularly soft tissues (p = 0.003). Despite the difference in response rate, when survival analysis was performed according to the Kaplan-Meier method, no significant difference was observed in the two groups, but when the analysis was limited to responsive patients, the median survival observed in those with a low and those with a high rate of proliferation was 35 and 19 months respectively (p = 0.02). The same results were obtained when multivariate survival analysis was carried out using Cox's regression model. These data suggest that there is a link between tumor proliferative activity and response to chemotherapy in advanced breast cancer, and may indicate the need to use more intensive treatments in selected patients with highly proliferative tumors.Presented in part at the Annual Meeting of the American Society of Clinical Oncology, May 14–17, 1994, Dallas, TX, USA  相似文献   
90.

Background

Exercise and dipyridamole 99mTc-labeled methoxy isobutyl isonitrile (MIBI) myocardial scintigraphy have been widely used for the diagnosis of coronary artery disease (CAD). However, only limited data on adenosine 99mTc-labeled MIBI cardiac imaging are currently available. This study was designed to assess the accuracy of quantitative adenosinerest 99mTc-labeled MIBI tomography in the diagnosis and localization of CAD.

Methods and Results

Fifty-seven consecutive patients with suspected CAD who underwent coronary angiography and 22 normal volunteers were studied. All patients underwent 99mTc-labeled MIBI tomography after administration of adenosine (140 μg/kg intravenously for 6 minutes) and at rest. A total of 171 vascular coronary territories were analyzed quantitatively. All patients with CAD (≥50% luminal stenosis) (n=55) had abnormal 99mTc-labeled MIBI tomograms. The normalcy rate was 86% by quantitative analysis. Overall sensitivity, specificity, and diagnostic accuracy for detection of individual stenosed vessels were 84%, 87%, and 85%, respectively. In patients with one-vessel CAD (n=24), sensitivity and diagnostic accuracy in the detection of individual stenosed vessels were significantly (p<0.05) higher compared with patients with multivessel CAD (n=31). Moreover, 75% of patients with one-vessel disease showed a scintigraphic pattern characterized by the presence of perfusion defects in only one coronary artery territory, and 74% of patients with multivessel disease showed a scintigraphic pattern characterized by the presence of perfusion defects in two or more coronary artery territories. Sensitivity, specificity, and diagnostic accuracy for detecting individual diseased vessels were similar in patients without previous myocardial infarction (n=18) compared with those with previous myocardial infarction (n=39). In myocardial territories related to noninfarcted areas (n=124), sensitivity and specificity in the detection of stenosed vessels were 75% and 88%. In infarcted areas (n=47), sensitivity and specificity in the detection of stenosed vessels were 98% and 80% (differences not significant vs noninfarcted areas).

Conclusions

Adenosine-controlled coronary vasodilation combined with quantitative 99mTc-labeled MIBI tomography is accurate for identifying patients with CAD and localizing individual stenosed coronary arteries.  相似文献   
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