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101.
Neuroradiological features of intracranial and intraorbital meningeal haemangiopericytomas 总被引:9,自引:1,他引:8
J. Ruscalleda M. Feliciani A. Avila E. Castañer E. Guardia M. de Juan 《Neuroradiology》1994,36(6):440-445
The neuroradiological features of six intracranial and one intraorbital haemangiopericytomas (HP) are reviewed. CT was performed before and after IV contrast medium in 5 patients. In 2 patients MRI was performed before and after contrast medium; in another, only unenhanced images were obtained. Five patients were studied by selective external and internal carotid artery angiography. Women constituted 5 of the 7 patients, and the mean age was 50.5 years, thus the sex and age distribution did not differ from that of typical meningiomas. Contrary to previous reports, calcification was present in two of the intracranial HP, and bone erosion was clearly seen in one intracranial HP and the orbital lesion. On MRI the tumours showed no differences from angioblastic meningiomas. All 6 intracranial HP were aggressive; all recurred following treatment and extracerebral metastasis occurred in one case. 相似文献
102.
Suzanne D. LeBlang M.D. Diego B. Nuñez M.D. Luis A. Rivas M.D. Steven Falcone M.D. Susan E. Pogson R.T. 《Emergency radiology》1997,4(4):200-206
The purpose of this study was to evaluate the ability of helical computed tomographic angiography (HCTA) to detect vascular injury in penetrating neck trauma. Thirty-five patients (30 gunshot wounds and 5 stab wounds) were studied prospectively with HCTA. Scans were performed with a 5-mm slice thickness at a 1:1 pitch after injection of 90 ml of nonionic contrast medium (30-second delay) at 3 ml/sec. Results were compared with those for angiography (29), surgery (3), ultrasound (2), and local inspection (1). HCTA correctly revealed 19 normal and 10 abnormal studies. In 8 cases, HCTA revealed irregular vessel margins (3), contrast extravasation (2), lack of vascular enhancement (1), and caliber changes (2). In 2 patients, HCTA revealed indirect signs of injury only. In 6 cases, HCTA findings did not correlate with angiography. HCTA detects both direct and indirect signs of vascular injury. Although indirect findings are more sensitive, the direct evaluation of vessels increases the specificity and has a high negative predictive value. 相似文献
103.
Patricio López-Jaramillo Director Marcelo Narváez Professor rés Calle Professor José Rivera Consultant Patricio Jácome Registrar César Ruano Professor Eduardo Nava Consultant 《BJOG : an international journal of obstetrics and gynaecology》1996,103(1):33-38
Objective To elucidate the role of the L-arginine: nitric oxide pathway in pregnancy and pre-eclampsia.
Participants Pregnant women (nulliparous, age < 25 years). Normotensive pregnancy ( n = 22 ) was defined when blood pressure remained at levels of < 120/80 mmHg and there was no proteinuria. Women with pre-eclampsia ( n = 22 ) had blood pressure measurements of > 140/90 mmHg and proteinuria of > 300 mg/l. Nonpregnant normotensive women ( n = 22 ) were studied as controls.
Study Design Blood samples were taken for measurements of ionised calcium, atrial natriuretic factor, cyclic guanosine 3'5'monophophate (GMP), arginine and asymmetric dimethylarginine. Urine samples were collected for determination of cyclic GMP excretion. Cyclic GMP concentrations were also determined in 12 women with severe pre-eclampsia before and after treatment with hydralazine.
Results L-arginine, asymmetric dimethylarginine and atrial natriuretic factor were not different in any group. Cyclic GMP concentrations in plasma [0.94 (SD 0.23) nM] as well as in urine [50.1 (SD15.7)μM] were increased significantly ( P < 0.05 ) in normal pregnancy compared to nonpregnant controls [plasma mean 0.46 (SD 0.12) nM and urine mean 18.4 (SD 10.3) μM], but not in the pre-eclampsia group [plasma mean 0.48 (SD 0.10) nM and urine mean 24.1 (SD 14.5) μM]. Concentrations of cyclic GMP in plasma and urine increased significantly ( P < 0.05 ) in women treated with hydralazine.
Conclusions The differences in cyclic GMP concentrations may reflect differences in nitric oxide production. Hydralazine increases cyclic GMP concentrations in severely pre-eclamptic women. This action could explain the antihypertensive effect of hydralazine. 相似文献
Participants Pregnant women (nulliparous, age < 25 years). Normotensive pregnancy ( n = 22 ) was defined when blood pressure remained at levels of < 120/80 mmHg and there was no proteinuria. Women with pre-eclampsia ( n = 22 ) had blood pressure measurements of > 140/90 mmHg and proteinuria of > 300 mg/l. Nonpregnant normotensive women ( n = 22 ) were studied as controls.
Study Design Blood samples were taken for measurements of ionised calcium, atrial natriuretic factor, cyclic guanosine 3'5'monophophate (GMP), arginine and asymmetric dimethylarginine. Urine samples were collected for determination of cyclic GMP excretion. Cyclic GMP concentrations were also determined in 12 women with severe pre-eclampsia before and after treatment with hydralazine.
Results L-arginine, asymmetric dimethylarginine and atrial natriuretic factor were not different in any group. Cyclic GMP concentrations in plasma [0.94 (SD 0.23) nM] as well as in urine [50.1 (SD15.7)μM] were increased significantly ( P < 0.05 ) in normal pregnancy compared to nonpregnant controls [plasma mean 0.46 (SD 0.12) nM and urine mean 18.4 (SD 10.3) μM], but not in the pre-eclampsia group [plasma mean 0.48 (SD 0.10) nM and urine mean 24.1 (SD 14.5) μM]. Concentrations of cyclic GMP in plasma and urine increased significantly ( P < 0.05 ) in women treated with hydralazine.
Conclusions The differences in cyclic GMP concentrations may reflect differences in nitric oxide production. Hydralazine increases cyclic GMP concentrations in severely pre-eclamptic women. This action could explain the antihypertensive effect of hydralazine. 相似文献
104.
D Martínez-Ares I Martín-Granizo Barrenechea J Souto-Ruzo J Yá?ez López A Pallarés Peral J L Vázquez-Iglesias 《Revista española de enfermedades digestivas》2005,97(12):877-886
INTRODUCTION: Colon cancer is one of the main causes of cancer death. Diagnosis requires the examination of the entire large bowel by means of radiological or endoscopic techniques. Many patients suspect of colon cancer are referred for colonoscopy but nevertheless this suspicion is not confirmed after endoscopic examination. The objective of this study is the evaluation of the reliability of abdominal ultrasound in the diagnosis of these tumors. MATERIAL AND METHOD: We selected patients suspect of colon cancer referred to the endoscopy unit for a colonoscopy. An abdominal ultrasound was carried out on all patients prior to the endoscopy. Considering the endoscopic examination as a gold standard, the sensibility, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the ultrasonography were evaluated. Likewise, a series of analytical and clinical parameters were evaluated, in an attempt to establish associated factors of a colon cancer. The statistical analysis was carried out by means of the statistical package SPSS 12.0 for Windows. RESULTS: 145 patients were included in the study (56.6% males) with an average 66.72 years of age (22-89). A cancer was diagnosed in 42 cases (28.9%). In the diagnosis of colon cancer, abdominal ultrasound presents a sensitivity of 79.06%, a specificity of 92.15%, a PPV and a NPV of 80.9% and of 91.2%, respectively. Excluding from the analysis lesions of the rectal ampulla, which cannot be adequately evaluated by means of ultrasound, the figures for sensitivity, specificity, PPV and NPV increase to 91.8, 92.1, 80.9 and 96.9% respectively. The univariate analysis showed that an age over 65 years and the presence of microcytosis are associated to a greater risk of colon cancer while after multivariate analysis only the presence of microcytosis resulted to be an independent predictive factor of cancer. CONCLUSIONS: Abdominal ultrasound presents high sensitivity, specificity, PPV and NPV in the diagnosis of colon cancer. The combination of an ultrasonography and a rectoscopy permits us to rule out the presence of a colorectal carcinoma. In patients with microcytosis of 65 years and over, if there is strong clinical suspicion, a negative ultrasound may not be sufficient to rule out a colorectal neoplasia. 相似文献
105.
R. M. Escorihuela A. Fernández-Teruel A. Tobeña W. Langhans K. Bättig P. Driscoll 《Behavior genetics》1997,27(6):573-578
An inbreeding program has been carried out with the Swiss sublines of Roman high- and low-avoidance rats since 1993. The present study reports the first experiments conducted with young animals of those inbred strains (RHA-I/Verh and RLA-I/Verh, respectively) from the sixth and seventh inbreeding generations. The results confirmed expected behavioral profiles. Compared to the RHA-I/Verh strain, RLA-I/Verh rats showed decreased entries into the illuminated central arena of an hexagonal tunnel maze, as well as decreased spontaneous locomotor activity and increased defecations, in two independent experiments. Young RLA-I/Verh females explored less than did their RHA-I/Verh counterparts during session 1 of a conditioned-fear experiment preceding shock administration, and in session 2 (conducted 24 h after the application of three footshocks), they showed greater conditioned behavioral inhibition (i.e., reduced amount of rearing), as well as higher defecation scores, than did RHA-I/Verh females.Karl Bättig tragically and unexpectedly died on December 27, 1996 相似文献
106.
M. Castro-Gago E. Cid Fernández J. Eirís Puñal P. Pavón Belinchón A. Rodríguez-Nuñez S. Rodríguez-Segade F. Camiña Darriba 《Child's nervous system》1996,12(6):315-317
Adenosine monophosphate, inosine monophosphate, inosine, adenosine, guanosine, adenine, guanine, hypoxanthine, xanthine and uric acid were determined in cerebrospinal fluid (CSF) of 15 children after complex febrile seizures (CFS) and in 27 after simple febrile seizures (SFS), and compared with those in a control group of 63 children. There was no statistically significant difference between the groups for any of these metabolites, suggesting that CFS and SFS neither significantly disturb the metabolism of nucleotides, nucleosides or bases nor significantly deplete neuron adenosine triphosphate levels. 相似文献
107.
Pilar Prieto-Alvarez Isabel Tello-Galindo Jesus Cuenca-Peña Maria Rull-Bartomeu Carmen Gomar-Sancho 《Journal canadien d'anesthésie》2002,49(1):25-31
PURPOSE: To compare two protocols of epidural administration of racemic methadone for postoperative analgesia (continuous infusion and intermittent bolus), focussing on plasma concentration, analgesic efficacy and side effects. METHODS: Ninety patients undergoing abdominal or lower-limb surgery were randomly assigned to two groups in a prospective double-blind design. The continuous infusion patients (n=60) received initial doses of 3 to 6 mg followed by 6 to 12 mg by continuous infusion over 24 hr. The bolus administration patients (n=30) received repeated boluses of 3 to 6 mg of racemic methadone every eight hours. Pain intensity was assessed on a visual analog scale. Amount of supplementary analgesia was recorded, as was the incidence of side effects. Plasma methadone concentrations were determined by high performance liquid chromatography. Treatment was continued for 72 hr. RESULTS: Pain relief was good and comparable in both groups throughout the three days of treatment. No accumulation of plasma racemic methadone was observed in either group, although the concentrations were significantly higher in the bolus group. Miosis was significantly more frequent in the bolus group. CONCLUSION: Plasma methadone concentrations were significantly lower with continuous infusion. Plasma methadone accumulation, which is considered the main disadvantage for its purported influence on the incidence of side effects, did not occur at the doses used over the three days of treatment that we report. 相似文献
108.
Luis Erik Clavería Jacinto Duarte Maria Dolores Sevillano Angel Pérez-Sempere Carmen Cabezas Fernanda Rodríguez Jesús de Pedro-Cuesta 《Movement disorders》2002,17(2):242-249
We assessed the prevalence of Parkinson's disease in Cantalejo, Spain. In 1994, we screened 1,579 persons (age > or = 40 years) using a high-sensitivity method. Cases fulfilling established clinical criteria were followed for a minimum of 3 years. Prevalences were compared with those from other door-to-door surveys. We detected 27 individuals with parkinsonism, 20 of whom had Parkinson's disease. The prevalence of Parkinson's disease increased with age and, when age-adjusted to European standards, was 9.01 per 1,000 (age 40 years and over; 10.78 in men and 5.23 in women). Of the 11 men, three were in Hoehn & Yahr grades III-IV, but six of the nine women were more severely affected. Overall, we found 18 newly diagnosed cases of parkinsonism, 13 of which were Parkinson's disease, and the majority of which were in men aged 80 years or older with a mean duration of illness of 5 years. Our prevalence figures are the highest reported, apparently because of the inclusion of several very elderly men. Parkinson's disease in Cantalejo is less severe in men than in women, particularly in those newly diagnosed. Despite the low numbers, the high prevalence and sex-related pattern are unexplained but they probably relate to the high sensitivity of the screening method. 相似文献
109.
A Velázquez C Martín-del-Campo A Báez S Zamudio M Quiterio J L Aguilar B Pérez-Ortiz M Sánchez-Ardines J Guzmán-Hernández E Casanueva 《European journal of clinical nutrition》1989,43(3):169-173
Several of the clinical and biochemical manifestations of biotin deficiency also occur in severe protein-energy malnutrition (PEM). Average plasma biotin concentrations were lower in 16 malnourished children (10 with marasmus, 3 with kwashiorkor and 3 with marasmic kwashiorkor) than in 31 controls. Lymphocyte mitochondrial carboxylase activities were studied in 11 controls and in 10 patients with PEM; on the average, they were lower in the patients. Their activation indices (the ratio of enzyme activity in cells incubated with biotin to activity in cells incubated without the vitamin) were higher in PEM. All these differences were statistically significant. None of these parameters were age-dependent in a range between 3 and 72 months. Carboxylase activities and plasma biotin levels increased to normal during nutritional recovery in two malnourished patients who were further studied. These results suggest that there is biotin deficiency in severe PEM. Urinary biotin concentrations, expressed per g of creatinine, were higher in the patients than in the controls; this may have been caused by increased renal clearance or by the reduced creatinine excretion which occurs in malnourished individuals. It will be important in future studies to determine the relative contribution of biotin deficiency to the malnourished phenotype. 相似文献
110.