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81.
M Marín-Padilla 《The Journal of comparative neurology》1992,321(2):223-240
The prenatal development of the mammalian neocortex has been analyzed, with the rapid Golgi method, in a variety of experimental animals (hamster, mouse, rat, and cat) and in humans. A new developmental conception of the structural organization of the mammalian neocortex is discussed. Neocortical development begins with the establishment of the primordial plexiform layer (PPL) which precedes and is a prerequisite for the subsequent formation of the cortical plate (CP). The formation of the CP occurs, in its entirety, within the PPL. During its development, three fundamental neuronal events occur: migration, early differentiation, and late maturation. All migrating neurons, travelling on radial glial fibers, reach layer I, develop an apical dendrite, and establish contacts with its elements. These newly differentiated neurons assume similar morphology resembling embryonic pyramidal cells. As such, an early differentiation stage common to all neurons of the CP is established. During the late maturation stage, all CP neurons acquire their specific phenotypic structural and functional features. Only pyramidal neurons retain and expand their original connections with layer I while other neuronal types lose these connections. The pyramidal cell is redefined in developmental terms: the neocortex's pyramidal cell is both structurally and functionally locked into position between layer I and the cortical depth of its soma. During mammalian evolution pyramidal cells are forced to structurally and functionally elongate their apical dendrite outwardly to accommodate an increasing amount of information without losing either their original anchorage to layer I or their cortical depth. This unique property of pyramidal neurons is considered to be a mammalian innovation. Based on these observations, a unifying developmental cytoarchitectonic theory applicable to all mammals is proposed. The theory considers the CP to be a mammalian innovation and to represent a single, stratified, and expanding telencephalic nucleus. The theory envisions the mammalian neocortex as an open biological system capable of progressive expansion by the recruitment and transformation of primitive neurons from upper layer II into pyramidal cells. Hence, the number of pyramidal cell strata increases over the course of mammalian phylogeny. The developmental roles of layer I in the migration of neurons, formation of the CP, unique morphology of pyramidal cells, and overall structural organization of the mammalian neocortex are emphasized. 相似文献
82.
83.
J V Pernía Morán P Rubio Pascual C Siminiani I Lahoz 《Revista espa?ola de anestesiología y reanimación》1990,37(2):98-100
We report the case of a 32-year-old multipara who presented preeclampsia on the fourth day after childbirth without receiving proper treatment that progressed to eclampsia 4 days later. Pregnancy and delivery had been uneventful. The patient presented proteinuria (30 mg/dl), serum total proteins 5.3 g/dl and serum albumin 3.3 g/dl. Blood pressure was controlled with methyldopa, 500 mg at six-hour intervals by intravenous route. The patient presented hypoxemia secondary to bilateral pleural effusion and aspirative pneumonia requiring mechanical ventilation and invasive hemodynamic monitoring. Treatment with cefotaxime, 1 g at six-hour intervals by intravenous route and clindamycin, 600 mg at six-hour intervals by intravenous route was initiated. Sedation was maintained with thiopental sodium, 3 mg/kg/hour in continuous infusion. At dismission, the patient was completely recovered from her clinical picture and needed no antihypertensive therapy. Physiopathologic features and the aforementioned complications are discussed with particular reference to differential diagnosis. 相似文献
84.
The use of decision analysis in selecting a histamine H2-receptor antagonist for the formulary at a hospital in Spain is described. Cimetidine, ranitidine, and famotidine were identified as the possible alternatives. The evaluation criteria established were therapeutic efficacy, adverse effects, drug interactions, years of clinical use, dosage interval, cost, and dosage forms. The relative importance of the criteria was determined by assigning utility values to each. Probability values were assigned to estimate how well each drug met each criterion. By multiplying the utility and probability values for each criterion and summing the scores, a total score was calculated for each drug. The alternative with the highest total score was ranitidine. A sensitivity analysis showed that the results were stable over a plausible range of probability and utility values. Accordingly, ranitidine was selected for inclusion on the formulary. Decision analysis provided an effective method for selecting which histamine H2-receptor antagonist to include on the hospital's formulary. 相似文献
85.
R. Gil-Grande J. M. Aguado C. Pastor M. García-Bravo C. Gómez-Pellico F. Soriano A. R. Noriega 《European journal of clinical microbiology & infectious diseases》1995,14(1):64-67
A patient with culture-negative endocarditis was diagnosed with Q fever endocarditis based on the results of serological tests and positive leukocyte cultures obtained using conventional viral cultures and the shell vial technique. This case report suggests that isolation ofCoxiella burnetii from blood may allow better diagnostic and therapeutical evaluation of patients with Q fever endocarditis. The use of both conventional and shell vial viral cultures is recommended for the isolation ofCoxiella burnetii from the blood of patients with apparently culture-negative endocarditis. 相似文献
86.
87.
F. M. González Valverde F. Mauri Barberá M. Molto Aguado N. Torregrosa A. Hernández Quiles F. Menárguez Pina M. J. Gómez Ramos M. García Real J. A. Barreras Mateos J. L. Vázquez Rojas 《European Surgery》2004,36(4):253-256
Summary BACKGROUND: Endometriosis is a relatively common pathology in women of childbearing age and of low parity but rarely shows
extraperitoneal involvement. The main aim of this paper is to raise the attention of specialists to the necessity of carrying
out penetrating diagnosis of nonspecific extraperitoneal masses occurring in women of reproductive age. METHODS: We performed
a retrospective review of six patients diagnosed with extraperitoneal endometriosis who were treated at the Vega Baja University
Hospital (Spain) during the last 5 years. RESULTS: Surgical treatment had positive results in five patients. The preoperative
diagnosis was correctly made in only two patients. The accurate aetiology of endometriosis remains unknown and diagnosis is
based on clinical and cytopathological findings. CONCLUSIONS: Surgical treatment of extraperitoneal endometriosis is recommended.
However, postoperative follow-up is obligatory and hormonal suppressive therapy may be necessary. Medical treatment with gestagens,
Danazol, or agonists of the gonadotropin-releasing hormone are ineffective in endometriomas which are bigger than 2 cm.
相似文献
88.
Ana Martín-Ancel María Luisa Casas Bartolomé Bonet 《Infection control and hospital epidemiology》2004,25(7):611-613
A neonate vaccinated against HBV was the source of an occupational exposure to blood. She was tested for hepatitis B surface antigen and found to be positive, leading to unnecessary treatment, retesting, and concern. Evaluation of the infectious status of HBV should rely on other means if vaccination has recently occurred. 相似文献
89.
José Ramón Cansino Alcaide Luis Martínez-Piñeiro 《Clinical & translational oncology》2006,8(3):148-152
Summary Genes involved in cancer generation are usually tumor suppressors and oncogenes. Progressive genetic alterations in these
genes are involved in the mechanisms of tumorigenesis. In prostate cancer, additionally several chromosomal loci that should
harbor mutated genes have been proposed. Some genes have been found altered in prostate cancer, such as PTEN, TP53, AR, RNASEL
(HPC1), ELAC2 (HPC2), CDKN2A and MSR1 and those can be natural targets for new strategies of treatment. Besides, gene therapy
has been suggested to be suitable for prostate cancer treatment. This approach includesex vivo corrective therapy, suicide, and antisense therapy. 相似文献
90.
L Rivera D Prieto M Hernández S Benedito A García-Sacristán 《Journal of the autonomic nervous system》1991,34(2-3):95-102
The distribution of cholinergic nerve fibres, as well as the characterization of the muscarinic receptors responsible for the contraction, were determined in the detrusor smooth muscle of the sheep. The results obtained demonstrated a rich presence of acetylcholinesterase (AChE)-positive fibres distributed throughout the bladder body forming dense neuromuscular, subepithelial and perivascular plexuses. Furthermore, intramural ganglia containing AChE-positive cell bodies were identified. However, acetylcholine and carbachol induced a dose-dependent contraction of detrusor smooth muscle. The effect observed with carbachol was competitively antagonized by atropine (pA2: 8.94), pirenzepine (pA2: 7.38), AF-DX 116 (pA2: 7.35), 4-DAMP (pA2: 9.26) and hexahydroxiladifenidol (HHSiD) (pA2: 8.49). The pA2 value for pirenzepine is intermediate between M1- and M2-receptors which suggests that this antagonist does not act on M1- or M2-receptors, but that it does on M3-receptors. The pA2 value for AF-DX 116 is consistent with the presence of M2-receptors in this tissue. Moreover, the pA2 values obtained for both 4-DAMP and HHSiD are in agreement with the presence of M3-receptors, due to the lack of effect of pirenzepine on M1-muscarinic receptors. These results indicate the existence of a rich parasympathetic innervation in the sheep detrusor muscle and suggest that its contraction could be mediated by the stimulation of muscarinic receptors belonging to both M3- and M2-subtypes. 相似文献