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131.
R Mollà J M Garcia-Verdugo C López-Garcia V Martín-Perez 《Journal für Hirnforschung》1986,27(6):625-637
The neuronal morphological development of the avian telencephalic cortex (DMC) is studied in Golgi-stained brain sections. The neuronal types at embryonic days 10, 13, 16, as well as of newborn chick are identified. The immature neurons are characterized by the presence of hair-like processes, growth cones and dendritic varicosities. These characteristics are absent in neuronal types of newborn chick. There are five patterns of differentiation, which produce six neuronal types in the newborn chick: horizontal neurons, pyramidal neurons, bipyramidal neurons, short axon multipolar neurons, long axon multipolar neurons and periventricular neurons. The morphological features of migrating embryonic cells are described. The dendritic spines appear in 16-day embryos in the majority of neuronal types. 相似文献
132.
Carmen Guillén Ponce María Pilar Garrido López María José Molina Garrido Gema Muñoz Molina Alfredo Carrato 《Clinical & translational oncology》2007,9(1):53-55
Pituitary metastases of solid tumours are infrequent, specially as a first manifestation. When they happen, they are usually
due to breast or lung cancer and are asymptomatic or produce diabetes insipidus. It is very strange that they produce hormonal
deficiency.
We present a case report of a bronchogenic adenocarcinoma in a 65-year-old man which began with panhypopituitarism, diabetes
insipidus and visual alterations. Magnetic resonance imaging revealed a large sellar mass, with clivus infiltration and invading
the right cavernous sinus. The biopsy result was adenocarcinoma metastases from lung cancer. 相似文献
133.
Dónal P O'Mathúna 《BMC medical ethics》2006,7(1):2-12
Background
The justification for Nazi programs involving involuntary euthanasia, forced sterilisation, eugenics and human experimentation were strongly influenced by views about human dignity. The historical development of these views should be examined today because discussions of human worth and value are integral to medical ethics and bioethics. We should learn lessons from how human dignity came to be so distorted to avoid repetition of similar distortions. 相似文献134.
G Oberhuber T Schmid R Erdk?nig W Thaler D Ofner G K?r?szi G Klima R Margreiter 《European surgical research. Europ?ische chirurgische Forschung. Recherches chirurgicales européennes》1991,23(3-4):206-213
The effect of ciclosporin (CS) and methotrexate (MTX) on the development of graft-versus-host (GvH) disease was examined after small bowel allotransplantation in the rat. The drugs were tested either alone or in combination. Lewis small bowel allografts were transplantated into Brown Norway recipients in a heterotopic position. The native small bowel, spleen, liver, skin, mesenteric lymph nodes and the kidney of the recipients were examined histologically 5, 10 and 20 days after allotransplantation. Intraepithelial lymphocyte numbers were determined quantitatively in the native small bowel. The relative spleen weight of the host was determined after sacrifice for estimation of the severity of GvH disease. Grade I GvH reaction of the native small bowel occurred in the animals without immunosuppression, but graft rejection predominated in this group. Treatment with CS was effective in the early postoperative periods; after 10 and 20 days GvH lesions in the native small bowel were comparable to those observed in the allogeneic combinations. MTX had a detrimental effect on the allografts and the GvH reaction was augmented. When CS and MTX were combined, GvH lesions were comparable to those in the animals treated solely with CS. Animals, however, suffered from heavy side effects. The spleen, liver, lymph nodes and kidney exhibited only unspecific histologic changes, which could not unequivocally be recognized as a GvH reaction. This was true for all groups. As a conclusion it can be said that GvH reaction occurs in the early postoperative period in a fully allogeneic model and cannot be prevented by CS in the dosae used. MTX was not seen to be of any value in this regard. 相似文献
135.
15 patients with congestive gastropathy were reported including clinical and pathological characteristics of the disease. Every patient had alcoholic liver cirrhosis and portal hypertension. 6 patient's stomach was resected while in 2 further cases the disease was found at autopsy. In additional 7 cases the characteristic microvascular changes were observed in endoscopic biopsy specimens from the gastric mucosa. The authors presume that this disease has an acute and a chronic stage. In the acute stage dilated capillaries are present under the surface, not related to the inflammation of gastric mucosa. This phenomenon was described in the literature. In the chronic stage there are dilated and tortuous vessels in the submucosal layer surrounded by collagenous connective tissue. The authors suppose that the thick and fibrotic submucosal layer causes microcirculatory disturbances in the gastric mucosa. The impaired microcirculation may cause extensive ulcers with profuse and sometimes lethal bleeding. 相似文献
136.
137.
Successful pregnancy in primary glomerular disease 总被引:2,自引:0,他引:2
The course of 66 pregnancies was studied in 48 women with primary glomerular diseases. In all cases diagnoses were established by biopsy before pregnancy. They were: membranoproliferative glomerulonephritis in 16 patients, focal glomeruloesclerosis in 13, IgA nephropathy in 10, membranous nephropathy in seven and focal glomerulonephritis in two women. The clinical status of the nephropathy before conception was that 43 had only mild renal dysfunction, five had moderate renal insufficiency, serum creatinine (1.3 to 1.9 mg%), eight women had hypertension (150/100 mm Hg) and eight had nephrotic range proteinuria. Their clinical course was compared with a control group of 36 women with primary glomerular disease who did not become pregnant, and were matched for similar age, histological type, and status of nephropathy (renal function, blood pressure and proteinuria). After one year and at the end of the five year follow-up period, the incidence of hypertension, proteinuria, and renal failure was similar in the two groups. The fetal survival rate was 92%; 51 pregnancies ended in full-term delivery, with a mean birthweight of 3,242 +/- 320 g. There were seven pre-term deliveries (2,170 +/- 135 g), three small for gestational-age (2,340 +/- 135 g), two stillbirths and three spontaneous abortions. These patients had more pre-term deliveries (10.6%) and perinatal mortality (31%) than a normal population (5.5% and 9.6%, respectively). Blood pressure increased during pregnancy in 13 women; in 10 it was reversible, and in four it persisted after delivery. Ten gravidas developed increased proteinuria (reversible in six of them) and two others developed permanent impairment of renal function.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
138.
Muscle strips from the fundus, trigonum and distal ureters obtained from children at operations for vesico-ureteric reflux were studied using histochemical and immunohistochemical methods, and electrical nerve stimulation in an organ bath. A rich supply of cholinergic nerves was found and despite a partial atropine resistance the neurophysiological experiments indicated that the transmitter causing contraction of the detrusor muscle is acetylcholine. Imipramine, which is used in the treatment of enuresis, had no anticholinergic effect on the bladder in the doses used clinically. The adrenergic innervation was very sparse except around the ureter orifices. No contractile alpha-adrenoceptors could be detected but beta receptor mediated relaxation was found, which was neither of the beta 1 nor beta 2 type. A third type of beta receptor is postulated. Peptidergic nerves containing vasoactive intestinal peptide, VIP, were demonstrated in a few nerve terminals running along bundles of smooth muscle. No nerves containing enkephaline, somatostatine or substance P were found. VIP affected the detrusor muscle indicating a possible role as a modulator of transmitter action, while substance P had no effect. The anticholinergic and calcium antagonistic drug terodiline inhibited all muscle activity, whether it was induced by nerve stimulation, cholinergic drugs or a potassium rich solution, making it suitable for treatment of diurnal enuresis. 相似文献
139.
Stuttering and tetanic syndrome 总被引:1,自引:0,他引:1
140.
Summary Physeal distraction was applied with an external fixator to the triradiate cartilage of dogs with the aim of increasing the capacity of the acetabulum. The force was continued for from 2 to 6 weeks and the consequent changes were evaluated with regard to function and structure by radiography and microscopy. The distraction, without producing epiphysiolysis and destruction of the cartilage, resulted in expansion of the pelvic bones. The depth and volume of the acetabulum were increased, but the acetabular angle was decreased. Distraction also caused proliferation of the lacunar cells and the number of mammillary processes in the cartilage columns increased. Distraction can therefore be applied to the triradiate cartilage to enlarge the capacity of the acetabulum without producing epiphysiolysis.
Résumé Dans cette étude une distraction a été appliquée sur le cartilage en Y. Douze chiens bâtards, âgés de 2.5 à 4 mois, ont été utilisés pour cette expérimentation. Une force de distraction de 80 Newton a été appliquée d'emblée sur le cartilage en Y. L'application de cette force a été poursuivie sur les animaux pendant 2, 4 ou 6 semaines. A la fin de cette période, les changements de la cavité cotyloïde et du cartilage en Y ont été évalués sur le plan fonctionnel, morphologique, radiologique et histopathologique Aucune altération fonctionnelle n'a été mise en évidence dans les groupes opérés par rapport au groupe de contrôle. On a observé que la distraction a déterminé une expansion massive de l'ilion, du pubis et de l'ischion. Sur les hanches de contrôle la profondeur de la cavité cotyloïde a été évaluée à 13.5 mm, le volume à 1.96 cc et l'angle de la cavité cotyloïde à 29.9°. Après distraction ces valeurs ont été respectivement de 14.4 mm, de 2.10 cc et de 25.7°. La distraction entraîne donc un accroissement de profondeur et de volume de la cavité cotyloïde, mais inversement une diminution de l'angle de cette cavité. Ces résultats montrent que la distraction détermine une prolifération des cellules lacunaires et un accroissement des processus mammaires dans les colonnes du cartilage en Y. Ils montrent également qu'elle peut augmenter la taille de l'acetabulum.相似文献