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1.
Lymphoepithelioma-like carcinoma of the bladder is an uncommon neoplasm, of which 49 cases have been described in the English literature, none of which has been studied for p53 protein expression. We studied three muscle-infiltrating cases of this tumor using immunohistochemical, in situ hybridization and polymerase chain reaction (PCR) methods. The three cases were positive for epithelial markers and negative for lymphoid antigens in the tumoral syncytial areas. The intensive infiltrate of small cells was negative for epithelial and positive for lymphoid markers. This population was mainly made up of cytotoxic T-lymphocytes, positive for TIA-1. p53 protein was intensely positive in more than 90% of the epithelial component nuclei, being negative in the lymphoid cells. PCR study did not show mutations on p53. Both lymphocytes and epithelium were negative for Epstein–Barr virus markers, such as the latent membrane protein and EBER (Epstein–Barr-encoded RNA). The prognosis was very good after radiotherapy and chemotherapy treatment, preserving the bladder despite the muscle infiltration. The presence of an intense cytotoxic T-lymphocyte population may be related to this good prognosis. Both aspects, p53 protein status and T-lymphoid population, had never been studied before in bladder lymphoepithelioma-like carcinoma.  相似文献   
2.
Transdermic administration by electroporation has developed over recent years for applying drugs in a variety of pathological processes. However, mechanisms are still not finally settled. India ink was applied to the backs of guinea pigs and for the transdermic transport short, high-voltage pulses (TDES, Dencort Dell) were administrated. Punch biopsies (4 mm) immediately taken after 24, 48, 72, 96 and at 26 days were studied by light and electronic microscopy. The ultrastructural characteristics and image pigment particles were reported. Particles of India ink were observed in the stratum corneum and in the epidermic keratinocytes of samples studied immediately after treatment. Particles were also seen in the epidermic and folicular keratinocytes, and in the papillary and reticular dermis (among collagen fibers, vessel walls, and macrophages) in all the subsequent biopsies; but not in the controls, which were conducted with electromagnetic waves alone. No tissue alterations were observed. The efficacy and noninvasive nature of electroporation for the transdermic administration of macromolecules is confirmed.  相似文献   
3.
Effect of reserpine administration on sleep patterns was studied in chronically implanted adult turtles Gopherus berlandieri. Four states of vigilance that differed behaviorally and electrophysiologically were observed: active wakefulness, quiet wakefulness, quiet sleep, and active sleep. Animals spent 88 and 2.92% of the nychthemeral cycle in quiet and active sleep, respectively. The active sleep phases were of short duration reaching a mean of 22 ± 6 sec (mean ± SD) and showing an occurrence of 124 ± 33 (mean ± SD) throughout the 24-h period. High voltage spikes were observed during quiet sleep at a frequency of 37 ± 9 spikes/min (mean ± SD). Reserpine elicited a significant reduction in total sleep time and in the occurrence of high voltage spikes (P < 0.05). The number of active sleep episodes showed an important decrement throughout the nychthemeral cycle (P < 0.01). Our data provide electrophysiological and pharmacological evidence to support the analogy of reptilian and mammalian sleep. Drug Dev. Res. 39:115–120 © 1997 Wiley-Liss, Inc.  相似文献   
4.
Male patient, 73 year old, with papillary thyroid carcinoma treated by surgery, 131I and L-Tyroxine, with bone metastasis, detected by bone scintigraphy and CT scan, which negative radioiodine uptake. In order to induce tumoral redifferentiation, retinoic acid (70 mg/day) was administered for three months before 131I treatment. A radioiodine scan performed after treatment showed uptake in some of the bone metastasis. Nine months later, and due to disease progression, a second induction with retinoic acid was performed before 131I treatment. The radioiodine scan performed after treatment showed greater uptake and higher number of bone lesions than the previous scan.  相似文献   
5.
Electrophysiological and behavioral characteristics of the states of vigilance were analyzed in chronically implanted specimens of the turkey Meleagris gallopavo (M. gallopavo). Five different states of vigilance were observed throughout the nyctohemeral period: active wakefulness (AW), quiet wakefulness (QW), drowsiness (D), slow wave sleep (SWS) and rapid eye movement (REM) sleep.These states exhibit characteristics similar to those described in other bird species. Sleep periods displayed a polyphasic distribution; however, they showed the tendency to concentrate between 2100 and 0900 h in spite of the fact that the recordings were carried out under constant illumination. Sleep period occupied 45.71% of the nyctohemeral cycle, 43.33% corresponded to SWS, while 2.38% to REM sleep. The average duration of the REM sleep phase was very short, lasting 7.7+/-0.55 s (mean+/-S.D.). In contrast, its frequency was very high with an average recurrence of 268+/-63 phases throughout the nyctohemeral cycle. The short duration of REM sleep phase presented by the turkey as by other bird species studied up to now may be dependent upon genetic factors shared by this group of vertebrates.  相似文献   
6.
7.
The brain stem of the lizard Ctenosaura pectinata was studied in 10 microns thick sections following the Nissl and eosin-hematoxilin techniques. Furthermore, the distribution of serotonin-containing neuronal somata in this encephalic region was determined by means of an indirect immunofluorescence technique using a specific antibody to serotonin. Two of the cellular groups of the brain stem were identified as the superior and inferior raphe nuclei, which show serotonergic cells of variable size (between 17 and 30 microns). The results obtained in the present study together with information coming from other authors, suggest that serotonergic neuronal systems placed at brain stem level of vertebrates are phylogenetically ancient.  相似文献   
8.

Purpose

Our aim was to analyze the value of ultrasound using the twinkling sign in the diagnosis of ureteral stones in patients with renal colic in the emergency setting.

Materials and methods

Prospective study of 100 patients with suspected renal colic who underwent an US examination, including color Doppler mode. We analyzed sensitivity, specificity, predictive values, and accuracy. We evaluated whether the stone was observed before or after the twinkling artifact, and whether the use of the Doppler color increased the examination time.

Results

US including color Doppler detected 76 of the 84 confirmed lithiasis. The sensitivity and specificity were 90 % and 100 %, respectively. The positive predictive value was 100 % and the negative 67 %. The accuracy was 92 %. A total of 59 calculi (78 %) examined by color Doppler sonography showed the twinkling artifact. Seventy percent of the twinkling-positive calculi showed the artifact before the stone itself was detected. Considering the location of the stones the twinkling sign was seen before the stone in 92 % of lithiasis located in the mid lumbar ureter (p = 0.02). The use of the twinkling artifact showed a trend to facilitate the detection of smaller calculi (<10 mm) (p = 0.08). The average examination time was 5.8 min [±4.3] (without differences between the stones detected before or after the twinkling artifact, p = 0.75).

Conclusion

Doppler US examination shows good sensitivity and specificity for the diagnosis of symptomatic ureteral stones. The twinkling artifact is useful for the early detection of the calculi, especially in the middle tract of the ureter, usually the most difficult place in sonographic diagnosis. It also seems helpful for the detection of smaller stones. The use of color Doppler does not increase the exploration time.  相似文献   
9.
10.
Transdermic administration by electroporation has developed over recent years for applying drugs in a variety of pathological processes. However, mechanisms are still not finally settled. India ink was applied to the backs of guinea pigs and for the transdermic transport short, high-voltage pulses (TDES, Dencort Dell) were administrated. Punch biopsies (4 mm) immediately taken after 24, 48, 72, 96 and at 26 days were studied by light and electronic microscopy. The ultrastructural characteristics and image pigment particles were reported. Particles of India ink were observed in the stratum corneum and in the epidermic keratinocytes of samples studied immediately after treatment. Particles were also seen in the epidermic and folicular keratinocytes, and in the papillary and reticular dermis (among collagen fibers, vessel walls, and macrophages) in all the subsequent biopsies; but not in the controls, which were conducted with electromagnetic waves alone. No tissue alterations were observed. The efficacy and noninvasive nature of electroporation for the transdermic administration of macromolecules is confirmed.  相似文献   
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