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991.
S Taba Shiwa N Garibay-Nieto P Angulo-Hernández F Vargas-Vorackova D Kershenobich 《Canadian Metallurgical Quarterly》1996,61(3):263-271
Surfactant abnormalities may contribute to the impairment of gas exchange observed in Pneumocystis carinii pneumonia. Analysis of rat bronchoalveolar lavage (BAL) lipid extracts from normal controls, steroid controls, trimethaprim-sulfamethoxazole (TMP-SMX) controls, TMP-SMX/P. carinii pneumonia controls, and P. carinii pneumonia animals reveal similar total phospholipid and total protein levels. However, there was a marked reduction in phosphatidylglycerol (PG) from the BAL of P. carinii pneumonia rats as compared with control animals, with a decrease from 4.91 +/- 1.29 nmol/mg protein to 0.46 +/- 0.57 nmol/mg protein (p<0.05) and a decrease, as a percent of total phospholipids, from 7.7% +/- 0.88% to 0.91% +/- 0.59% (p<0.001). Furthermore, in vitro surface activities of BAL lipid extracts from control and P. carinii pneumonia rats revealed minimum surface tension increases from 9.38 +/- 1.71 mN/m in controls to 16.36 +/- 0.83 mN/m in P. carinii pneumonia rats (p<0.05) and likewise maximum surface tension increases from 22.14 +/- 4.34 mN/m to 38.57 +/- 2.07 mN/m (p<0.01). Of interest, the surface activity of PG-deficient P. carinii pneumonia BAL lipid extracts is completely restored to that of normal controls by the addition of exogenous PG. These findings suggest that a functionally abnormal surfactant occurs in P. carinii pneumonia and that this may account, in part, for the impairment of gas exchange observed in this disorder. 相似文献
992.
EG Diego González A Méndez Lanza JA Mosquera Pesta?a 《Canadian Metallurgical Quarterly》1996,13(9):430-433
Whether a sulfonylurea may be used together with insulin for treating NIDDM has been controversial. One view, based on older studies, has been that the additional benefit is too small or the level of glucose control achieved usually too poor to recommend this method. More recent studies of a more specific way of combining a sulfonylurea with insulin are more supportive. When a single injection of insulin taken in the evening is added to a sulfonylurea at the time of secondary failure of the sulfonylurea alone, glycemic control is quite simply and consistently restored to acceptable levels. At this time in the natural history of NIDDM, evening insulin combined therapy is more effective than a single injection of insulin alone, and just as effective as a more complex multiple-injection regimen without an oral agent. A recent multicenter trial of a new sulfonylurea, glimepiride, in combination with a single injection of 70/30 insulin before dinner has confirmed that this approach is safe and more consistently effective than insulin alone for obese patients beginning insulin in a setting resembling clinical practice. The available evidence suggests this form of combined therapy is suitable for routine use. 相似文献
993.
AL Fernández González D Luna MA Martínez Monzonís JA Montero O Gil Albarova O Tovar 《Canadian Metallurgical Quarterly》1996,40(4):20-23
The authors report four cases of prolonged bradyarrhythmias after isolated coronary artery bypass graft surgery. All the four patients required permanent pacemaker implantation. Etiologic factors of conduction disturbances after coronary artery bypass and long term follow-up are discussed. 相似文献
994.
Initial reports on antiproteinuric effect of pefloxacine in small groups of patients with minimal-change nephropathy (MCN) and focal and segmental glomerulosclerosis (FSGS) have not been confirmed in other papers. To assess its antiproteinuric effect in experimental animals we administered pefloxacine to rats with adriamycin nephropathy showing morphological changes resembling human minimal-change disease or focal segmental glomerulosclerosis, and clinically with full-blown nephrotic syndrome. Pefloxacine treatment was at least partially effective in preventing further increase of proteinuria in rats with adriamycin nephropathy. The mechanism of this effect remains unclear and deserves further studies concentrating on the glomerular cytokine network and glomerular production of reactive oxygen species. 相似文献
995.
JM Ramos Fernández J Martínez San Millán R Barrio Castellano R Yturriaga Matarranz G Lorenzo Sanz JM Aparicio Meix 《Canadian Metallurgical Quarterly》1996,45(6):614-618
OBJECTIVE: Septo-optic dysplasia, which consists of the association of the hypoplasia of the optic nerves and the agenesis of the septum pellucidum, is frequently associated with deficiency of hypothalamic releasing factors. In Magnetic Resonance (MR) of these patients, anomalies in the form and size of the pituitary stalk, adenohypophysis and neurohypophysis are found. Some cases show schizencephaly and it has been proposed as an added component of the syndrome by some authors. This fact has been refuted by others. PATIENTS AND METHODS: We present the clinical and neuroanatomic revision of six children with septo-optic dysplasia studied by MR imaging over the last five years in our Department of Neuropediatrics. The aim was, that through the neuroembryological discussion of the morphopathological aspects of the patients, to determine the malformation and the time in which the injury, which was the underlying cause, occurred. RESULTS: From the six cases, in two only disruptive signs were evident with the optic nerves being affected asymmetrically, disruption of the corpus callosum, falx cerebri indemnity and effects in the cortex conformation. This was opposed to the dysgenic features in the other four cases which had no disruptive features. CONCLUSIONS: Our findings suggest that this entity could be the result of at least two different pathogenic processes, that is, a minor form of holoprosencephaly (dysgenesis) or a disruption which, therefore, occurs later in gestation. 相似文献
996.
F Herranz Amo E Rodríguez Fernández JM Díez Cordero E Lledó García F Verdú Tartajo F González Chamorro C Subira Castillón 《Canadian Metallurgical Quarterly》1996,20(10):858-866
OBJECTIVE: The objective of the study is to evaluate the infectious complications of the ultrasound-guided prostate transrectal biopsy using two different antibiotic prophylactic regimes. Also, patient tolerance to ultrasound-guided transrectal biopsy is assessed. METHODS: Prospective study in 100 patients randomized to antibiotic prophylaxis with Pefloxacin (800 mg as single dose) versus Ciprofloxacin (250 mg/8 h/72 h). Tolerance data collection was done through completion of a questionnaire immediately after biopsy. RESULTS: Out of the 92 patients eligible for the study, 44 (48%) were assigned to Pefloxacin and 28 (52%) to Ciprofloxacin. In-house validation indicated both groups were matched. 90% patients showed good tolerance to the ultrasound technique and 81.5% patients to the transrectal biopsy. 31.5% patients presented no post-biopsy events; among the remaining only one patient (1%) required medical care and hospitalization. No patient had infectious complications. CONCLUSIONS: Prostate transrectal ultrasound and transrectal prostate biopsy was an approach well tolerated by most (81.5%) patients studied. Percentage of major complications was very small (1%), while post-biopsy events (haematuria, rectorrhage, etc) which do not require medical care should be considered not as complications but as effects intrinsic to the approach itself. Antibiotic prophylaxis whether with Pefloxacin or Ciprofloxacine was highly effective, although Pefloxacin is preferred due to its single dose administration and lower cost. 相似文献
997.
A Rodríguez Nú?ez E Cid Fernández R Tojo Sierra JM Martinón Sánchez 《Canadian Metallurgical Quarterly》1996,44(5):461-463
OBJECTIVE: To review serious childhood injuries provoked by tractors in our country and to propose adequate preventative strategies. PATIENTS AND METHODS: Clinical data of eleven children admitted to our unit due to a tractor related accident have been evaluated. RESULTS: The majority of the events occurred in males and during the summer months, resulting in polytraumatisms with the abdominal region affected in most cases. Mortality was very high (64%). CONCLUSIONS: Accidents with tractors are a major preventable morbimortality factor in rural areas. Several preventive strategies that could reduce the incidence and severity of these injuries are proposed. 相似文献
998.
D Defey E Storch S Cardozo O Díaz G Fernández 《Canadian Metallurgical Quarterly》1996,42(10):1447-1456
Menopause has often been described as a time of loss and decay in the lay and medical literature. The present research aims at defining women's perception of themselves and their health care needs in this period of life. Through a community-based sample of women, participative assessments were performed and their conclusions contrasted with the opinions of male and female gynecologists. Though both groups coincided concerning the relevance of loneliness, partnership, beauty and the "empty nest" syndrome, several items showed a marked difference between both groups. Gynecologists tended to perceive women as much more striving for an active sex-life, depressed, lacking projects for the future and worried about their health care than they actually were. Women, instead, stressed the relevance of menopause as a life crisis laden with opportunities for self-accomplishment and positive changes in life-style towards greater autonomy. 相似文献
999.
Poststroke bipolar affective disorder: clinical subtypes, concurrent movement disorders, and anatomical correlates 总被引:1,自引:0,他引:1
ML Berthier J Kulisevsky A Gironell JA Fernández Benitez 《Canadian Metallurgical Quarterly》1996,8(2):160-167
The authors describe 9 patients with bipolar affective disorder associated with cerebrovascular lesions. Eight had negative family histories of affective disorders and late age at onset (after age 40) of manic-depressive symptoms. Only one, with positive family history of affective disorders, developed mood swings before age 40. Clinical subtypes of bipolar disorder and patterns of affective cycling in these stroke patients resembled those previously reported in functional bipolar disorder. Five patients had concurrent hyperkinetic movement disorders, and one depressed patient presented with unilateral left-sided parkinsonism that disappeared during a manic switch. In most patients, bipolar affective disorder was associated with right hemisphere lesions that involved subcortical and midline structures. Findings suggest that damage to frontal-basal ganglia-thalamocortical circuits by subcortical vascular lesions may simultaneously provoke disorders of movement and mood regulation. 相似文献
1000.
Comparing the sensitivity of similar direct and indirect measures is proposed as the best way to provide evidence for unconscious learning. The authors apply this approach, first proposed by E. M. Reingold and P. M. Merikle (see record 1989-21201-001), to a choice reaction-time task in which the material is generated probabilistically on the basis of a finite-state grammar (A. Cleeremans, see record 93:127012). The data show that participants can learn about the structure of the stimulus material over training with the choice reaction-time task, but only to a limited extent - a result that is well predicted by the simple recurrent network model of A. Cleeremans and J. L. McClelland (see record 1992-00389-001). Participants can also use some of this knowledge to perform a subsequent generation task. However, detailed partial correlational analyses that control for knowledge as assessed by the generation task show that large effects of sequence learning are exclusively expressed through reaction time. This result suggests that at least some of this learning cannot be characterized as conscious. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献