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991.
美尼尔与美尼尔病   总被引:1,自引:0,他引:1  
美尼尔生活在法国大革命之后医学繁荣时代。他长期从事耳科学实践活动,发现了传统上认为是卒中型脑充血的内耳疾病。尽管这种以他名字命名的疾病─美尼尔病被后世误解,但是,他的发现终于被科学发展所证实。现今人们正在为深入研究美尼尔病作不懈的努力,以期彻底将之征服。  相似文献   
992.
Opioids have been shown to produce analgesia and to be reinforcing during the first week of life in the rat. Opioids also have analgesic actions in both the infant and adult, but can be aversive in the mature animal. We examined the aversive effects of the opioid agonist U50,488 during the first postnatal week in the rat pup in three ways. In the first experiment, U50,488, injected peripherally (1.0–30.0 mg/kg), was paired with an odor and pups were tested 8 h later for positional preference for avoidance of that odor. This task is similar to conditioned preference/aversion tests used with adult animals. Both 3- and 7-day-old pups learned to avoid the odor adulterated side at the two higher doses. When exposed to odors previously associated with U50,488, pups at both ages decreased locomotor activity. In a second experiment, acute treatment with U50,488 increased ultrasonic distress vocalizations (USV) equally at 3 and 7 days of age, increased locomotor activity, and decreased rectal temperature. Neither of the latter two effects was correlated with the increase in USV production. The third experiment showed that conditioned odor cues increased USV 8 h later in 3- and 7-day-old pups at 1.0–10.0 mg/kg without changes in activity or rectal temperature. The results from these studies suggest that U50,488 can produce aversions in the neonatal rat pup as it does in the adult.Supported by U.S.P.H.S. grant DA-06600  相似文献   
993.
The glassy state of nifedipine (NP) was prepared in the absence and presence of 2-hydroxypropyl--cyclodextrin (HP--CyD), and its crystallization and polymorphic transition behavior was investigated by differential scanning calorimetry (DSC) and powder X-ray diffractometry. In DSC thermograms, the glassy NP exhibited an en-dothermic peak at 48°C representing the glass transition of NP, an exothermic peak at 105°C for the crystallization to a metastable form of NP (Form B), an exothermic peak at 125°C for the polymorphic transition of Form B to a stable form of NP (Form A), and an endothermic peak at 171°C for the melting of Form A. The powder X-ray diffractogram of Form B was apparently different from that of Form A. In the presence of HP--CyD, the exothermic peak at 125°C for the Form B to A transition disappeared and a new en-dothermic peak appeared at 163°C. This new peak was ascribed to the melting of Form B, and the conversion of Form B to Form A was significantly suppressed in HP--CyD matrix. Upon storage at 60°C, the glassy NP was converted to Form A with an activation energy of 18 kcal/mol. The apparent dissolution rate of the NP/HP--CyD (molar ratio 1:1) increased in the order of glassy NP < Form A < Form B, because the glassy NP was readily converted to Form A upon contact with water, resulting in a lower dissolution rate. The present data suggest that HP--CyD is useful for the preparation of a fast dissolving form of metastable NP through glassy NP.  相似文献   
994.
A prospective study in which the existence of iron metabolism alterations (increase in the serum levels of iron and ferritin and the presence of iron in liver tissue) in a group of 53 patients diagnosed with chronic anti-HCV positive hepatitis was performed. The aim of the study was to determine whether these parameters influence the response to interferon treatment. Elevations were observed in the serum levels of iron and/or ferritin in 17 (32%) of the patients. Higher than normal values of serum iron or ferritin in pretreatment analyses were associated with worse therapeutic response. The basal serum levels of iron and ferritin were significantly higher in non responding patients. No relationship was found between the presence of iron in the hepatic parenchyma and response to interferon treatment.  相似文献   
995.
Several patients with the Silver-Russell syndrome (SRS) attending our Genetics Clinic were diagnosed as having persistent metabolic acidosis. Since this abnormality has not been reported previously in the SRS, we reexamined 33 SRS patients to evaluate the frequency and type of metabolic acidosis, the clinical and laboratory findings, and the growth pattern in SRS patients with and without metabolic acidosis. Among them, 14 had a consistent decrease in HCO levels. Renal studies in acidotic patients showed urine pH of 5.8 and 24 h urine calcium of <2.4 mg/kg/24 h; serum creatinine, excretion of glucose, and aminoacids were normal, as were renal ultrasound and excretory urography findings. These data supported the diagnosis of renal tubular acidosis, probably type II; the patients were treated with oral bicarbonate and acidosis was corrected successfully. Clinical manifestations were similar in acidotic and non-acidotic patients. The nutritional indices at diagnosis and at last evaluation (at least 8 months after diagnosis) were abnormally low in all patients; however, acidotic patients, treated with bicarbonate, showed an improvement of nutritional status particularly in the weight/height index, although the difference between groups after follow-up did not reach statistical significance. We suggest that metabolic acidosis due to renal tubular acidosis, probably type II, may occur in children with the SRS and should be looked for and treated in all patients. © 1995 Wiley-Liss, Inc.  相似文献   
996.
While many neuropsychological studies have demonstrated age-related performance alterations in tests thought to reflect frontal and temporal lobe function, there is little direct observation and comparison of these hypothesized brain changesin vivo. The cerebral glucose metabolism of frontal, temporal, and cerebellar regions was examined in 40 young ( =27.5±4.9) and 31 elderly ( =67.6 ± 8.8) normal males using PET-FDG. Univariate analysis showed age-related metabolic reductions in all frontal and temporal lobe regions. The reductions ranged from 13%–24% with the greatest changes in the frontal lobes. Multiple regression analyses showed a stronger age relationship with frontal lobe than with temporal lobe metabolism. The dorsal lateral frontal lobe was the region that appears to change most within the frontal lobes. Examination of the temporal lobe showed that age contributed equally to the metabolic variance of both the lateral temporal lobe and hippocampus. These results suggest that age-related metabolic changes exist in both frontal and temporal lobes and that the frontal lobe change is greater.  相似文献   
997.
998.
Thrombosis of the hepatic artery (HAT) is a severe complication of liver transplantation, and most cases need regrafting. The aim of this study was to review our experience with this complication. From January 1986 through January 1992, 76 liver transplants were performed in 59 pediatric patients at the Children's Hospital La Paz, Madrid. The diagnosis of HAT was made in 12 cases (15.7%). The common patterns of clinical presentation were: fulminant liver necrosis (5), bile leak due to necrosis of the bile duct (4), and relapsing bacteremia (3). Clinical symptoms of fulminant liver necrosis started within the first 2 weeks after transplantation, with rapid deterioration and steep rises in SGOT and SGPT levels. All these patients were retransplanted on an urgent basis, but only 1 is alive 4 years later. Four patients developed bile leaks 13 to 60 days after transplantation; SGOT, SGPT, and total bilirubin were only slightly increased. Three children were retransplanted electively and are alive with a mean follow-up of 3 years. One exceptional patient had a Roux-en-Y jejunostomy and is doing well 30 months later with his original graft. The 3 remaining children had episodes of septicemia with hepatic abscess, liver infarction, and pleural effusion. Liver function tests were normal, with bilirubin levels below 2 mg/dl. All patients were retransplanted, but only 1 is alive and well 13 months later. In the present series, we found that early HAT produces fulminant clinical deterioration requiring an urgent regraft. Late HAT presenting with either infection or bile leak allows time for treatment by elective retransplantation. The best survival was obtained in the latter group. Correspondence to: J. Vázquez  相似文献   
999.
王盼 《中国卫生经济》1999,18(11):34-36
本文从产权的角度出发,对当前的医疗机构改革进行了分析,并对医疗机构自主经营、企业化经营过程中可能出现的一些问题,提出了政府作为财产的最终所有者应加强对医疗机构经营状况的监管。  相似文献   
1000.
Photovoice is a participatory action research strategy that may offer unique contributions to women's health. It is a process by which people can identify, represent, and enhance their community through a specific photographic technique. Photovoice has three main goals: to enable people (1) to record and reflect their community's strengths and concerns, (2) to promote critical dialogue and knowledge about personal and community issues through large and small group discussion of their photographs, and (3) to reach policymakers. This report gives an overview of the origins, key concepts, methods, and uses of photovoice as a strategy to enhance women's health.  相似文献   
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