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The authors describe a case of a giant intradiploic epidermoid cyst of the occipital bone with an intracranial extension in the posterior fossa and no signs of neurological involvement. The lesion started as a painless lump under the scalp. Roentgenographic and computed tomographic findings led to a correct diagnosis, and the complete removal of the cyst was accomplished, despite its large size. The total removal of these cysts is associated with a good prognosis. 相似文献
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R. G. Aguilera J. P. López R. R. Aldosa G. Rius-Espina 《International urology and nephrology》1990,22(4):367-371
A study of 16 patients who underwent intralbugineous testicular implants during the practice of orchiectomy is presented.
In 14 cases of prostatic carcinoma, after bilateral subcapsular orchiectomy intralbugineous prostheses were implanted and
in 2 other cases of testicular torsion unilateral prosthesis was implanted.
With this new, easily executed technique the size, mobility and testicular sensibility are maintained. 相似文献
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Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model. 相似文献
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G L Slick A J Aguilera E J Zambraski G F DiBona G J Kaloyanides 《The American journal of physiology》1975,229(1):60-65
To study the role of the renal sympathetic nerves in the regulation of sodium excretion, we examined the renal functional response to left renal nerve stimulation before (group I) and after (group II) left renal adrenergic blockade with guanethidine. In group I dogs, absolute sodium excretion from the left kidney fell markedly after left renal nerve stimulation; the decreases in glomerular filtration rate and renal blood flow were of a similar magnitude. Using the radiolabeled microsphere technique, distribution of renal blood flow to the outer cortex was diminished after left renal nerve stimulation. In group II dogs, guanethidine blocked all of these effects of left renal nerve stimulation. In group iii studies, a low level of left renal nerve stimulation was used which resulted in a decrease in sodium excretion in the absence of changes in glomerular filtration rate, renal blood flow, or intrarenal distribution of blood flow; this effect was blocked by renal adrenergic blockade with guanethidine in group iv studies. These data support a role for the renal sympathetic nerves to directly influence renal tubular sodium transport in the absence of alterations in renal hemodynamics. 相似文献
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Del Peso G Jimenez-Heffernan JA Bajo MA Hevia C Aguilera A Castro MJ Sanchez-Tomero JA Lopez-Cabrera M Selgas R 《The International journal of artificial organs》2005,28(2):135-140
OBJECTIVE: To analyze the presence of myofibroblasts in a series of peritoneal dialysis (PD) patients with simple sclerosis and non-PD, uremic patients. Since there is a close correlation between active fibrosis and myofibroblastic differentiation we wanted to test if myofibroblasts are present in uremic, non-PD peritoneal samples. To determine if there are correlations between myofibroblastic presence and other functional and morphologic peritoneal parameters. METHODS: Biopsies were collected from three patient groups: 1) Normal control samples (n = 15) of parietal and visceral peritoneum 2) non-PD uremic patients (n = 16); and 3) uremic patients on PD (n = 32). Peritoneal morphologic and functional parameters and immunohistochemical expression of alfa-smooth muscle actin was analyzed in each case. Vascular endothelial growth factor (VEGF), bcl-2 anti-apoptotic protein, and progesterone receptor was evaluated in a subset of cases. RESULTS: Myofibroblasts were present in 56.3% of the patients with PD-related simple sclerosis. In most cases they were distributed in the upper submesothelial area. None of the biopsies from normal controls and uremic, non-PD patients showed myofibroblasts. Within the group of PD patients, myofibroblasts showed no correlation with time on dialysis, urea/creatinine MTAC, episodes of peritonitis, submesothelial thickening, hyalinizing vasculopathy or mesothelial status. In a subset of PD patients VEGF expression was observed in submesothelial fibroblastic cells. No expression of progesterone receptor or bcl-2 was observed. CONCLUSIONS: Myofibroblasts are a reliable and simple indicator of fibrosis since they appear in early stages of PD treatment and in patients with minor morphologic anomalies. They are not exclusive of patients with sclerosing peritonitis, ultrafiltration loss or long standing treatment. Their absence in non-PD, uremic patients suggest that uremia-related fibrosis takes place without a significant participation of myofibroblasts. 相似文献
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Voltage-clamp techniques were employed to examine the effect of magnesium (Mg) on sodium transport in the isolated urinary bladder of the Dominican toad. Substitution of 1 mM Mg had no effect, but 3-mM Mg substitution resulted in a reversible increase in short-circuit current (27%) and potential difference (19%) and decrease in transepithelial resistance (14%); no greater effect was seen with 5- or 10-mM Mg substitution. The effect was produced by mucosal or mucosal and serosal Mg substitution; serosal Mg substitution was without effect. Analysis of electrical parameters disclosed that magnesium increased net sodium transport via an effect on the sodium pump. 相似文献