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1.
Vitiligo and psoriasis are both common skin disorders. However, psoriasis strictly confined to pre-existing vitiligo areas is rare and suggests a causal relationship. We report here on two patients with a strict anatomical colocalization of vitiligo and psoriasis. The histopathological examinations showed typical changes for both diseases together with a dense infiltrate of CD4+ and CD8+ T cells. By immunohistochemistry, intracytoplasmatic granzyme B and tumour necrosis factor alpha (TNF-alpha) were detected within the T-cell population, suggesting the functional activity of these cells and the creation of a local T helper 1 (Th1)-cytokine milieu. Additionally, in one patient we could identify anti-melanocytic T cells by tetramer staining and enzyme-linked immunospot (ELISPOT) analysis. These skin-infiltrating lymphocytes might trigger, by the local production of Th-1 cytokines such as TNF-alpha and interferon-gamma (IFN-gamma), the eruption of psoriatic plaques in patients with a genetic predisposition for psoriasis.  相似文献   
2.
The role of an operation in patients receiving neoadjuvant chemotherapy for clinically localized but invasive transitional cell carcinoma of the bladder currently is evolving. An operation is essential for case selection and evaluation of local response but it also contributes to bladder preservation and survival. The procedure that is necessary to select for and assess response to chemotherapy may itself alter the actual or proceed to evolution of invasive bladder cancer. Neoadjuvant chemotherapy is a reasonable therapeutic strategy in selected patients but it remains to be seen whether the results will prove to be superior to those achieved with standard endoscopic and open operations.  相似文献   
3.
Rupture of the corpus cavernosum is a rare but probably under-reported entity. It truly represents a urological emergency and current recommendations are for early surgical intervention. We review 5 cases with evaluation, treatment and followup. Delays in treatment lead to long-term complications, such as erectile dysfunction and penile curvature.  相似文献   
4.
In the mature rat, reflex sympathetic stimulation by insulin-induced hypoglycemia resulted in profound depletion of adrenal epinephrine, and to a lesser extent, norepinephrine. In the developing rat, insulin evoked little or no secretory response from the adrenals prior to 1 week of age. By 7 days, a moderate depletion of epinephrine was seen and the magnitude of the response increased with age. In contrast, during the first 3 weeks of postnatal life, insulin failed to deplete norepinephrine from the adrenal medulla and in fact, produced an increase. This chiefly resulted from de novo biosynthesis of the amine, as the rise was blocked by alpha-methyl-p-tyrosine. These results suggest that the ontogeny of the two chromaffin cell types (norepinephrine and epinephrine-containing) in the adrenals and the maturation of their secretory responses are under differential regulation. Because descending supraspinal catecholaminergic and serotonergic systems have been implicated to play key roles in regulating adrenomedullary function, the ontogeny of the sympatho-adrenomedullary axis was evaluated after neonatal central lesioning with 6-hydroxydopamine or 5,7-dihydroxytryptamine. 6-Hydroxydopamine resulted in a preferential elevation of epinephrine in the developing adrenals as well as an increase in the responsiveness of the adrenals to reflex stimulation by insulin; the mature secretory pattern was obtained as early as at 4 days postnatally for epinephrine and 9 days for norepinephrine. In contrast, 5,7-dihydroxytryptamine led to a preferential reduction of basal adrenal norepinephrine content.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
Clinical trials have utilized intermittent diethylstilbestrol diphosphate (DES) therapy in advanced symptomatic prostatic carcinoma to diminish the morbidity of standard endocrine therapy. To determine the effect of intermittent DES administration on the Dunning R3327 rat prostatic adenocarcinoma 60 days following tumor implant, 6 groups were randomly assigned: control (N = 8), castrate (N = 10), high dose DES (N = 8, 1.6 micrograms/ml DES continuously in drinking water), low dose DES (N = 10, 0.4 microgram/ml continuously in drinking water), intermittent high dose DES (N = 10, 1.6 micrograms/ml DES in drinking water for 1 week, then off for 3 weeks), and intermittent low dose DES (N = 10, 0.4 microgram/ml DES for 1 week, then off for 3 weeks). Results indicate that low or high dose DES, and intermittent low or intermittent high dose DES during the week of administration were able to reduce serum testosterone to castrate levels (0.1 ng/ml). After withdrawal of intermittent DES, serum testosterone returned toward control levels (1.0 ng/ml). Initial mean tumor burden between control and treatment groups was not significantly different. All DES exposed rats had a tumor volume at death (range, 15.6-18.3 cm3) smaller than control (mean, 25.4 cm3) or castrate (mean, 40.8 cm3) rats. Despite this significant survival advantage from the time of randomization was achieved only in castrate (median survival, 331 days) or high dose DES (median survival, 359 days) groups compared to control (median survival, 225 days). Similarly, significant prolongation in tumor doubling time was achieved only by rats receiving castration or high dose DES. Intermittent DES administration controls tumor volume but does not provide a survival advantage. In this respect, intermittent DES is inferior to castration.  相似文献   
6.
We treated 13 patients with a second 125iodine implant for local recurrence of prostatic carcinoma. All patients had biopsy proved palpable recurrence without evidence of distant metastases. Full doses of irradiation were used (median matched peripheral dose 170 Gy.). Six patients had complete regression of palpable recurrence, 2 had partial regression, 2 had no apparent response and 3 were unevaluable for local response. Actuarial freedom from local disease progression at 5 years was 51%. Despite a relatively high rate of local disease control the actuarial rate of distant metastases reached 100% at 6 years after reimplantation. There were 2 severe rectal complications and 4 instances of mild to moderate urinary incontinence among the 13 patients. Local regression of recurrent prostatic carcinoma may be achieved with 125iodine reimplantation but most patients still had distant metastases.  相似文献   
7.
8.
Medial border of the perirenal space: CT and anatomic correlation   总被引:11,自引:0,他引:11  
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9.
Circannual variation in lymphocyte subsets, revisited   总被引:2,自引:0,他引:2  
BACKGROUND: Circadian and circannual variations in lymphocyte subsets, especially CD8+ T-lymphocytes, have been reported. This study focuses on CD4+ T-lymphocyte seasonal variation over a 6-year 8-month period. STUDY DESIGN AND METHODS: Lymphocyte subsets were quantitated monthly for four healthy individuals from 1986 through 1992 as part of a flow cytometry quality-control program. RESULTS: In general, there were no significant seasonal changes in the total number of white cells or in total lymphocyte counts. The absolute numbers of CD4+ T-lymphocytes were lowest in summer when the CD8+ T-lymphocytes were highest. Mean CD4+ T-lymphocyte counts were 846, 967, 618, and 695 per microL for Subjects 1 through 4, respectively, in winter and 432, 670, 355, and 766 per microL, respectively, in summer. Two healthy subjects had CD4+ T-lymphocyte counts lower than 300 per microL on one or more occasions during the study period. In three of the four subjects, the percentage of B-lymphocytes in winter was almost double that in summer. In one of the four subjects, no circannual rhythm was observed in these lymphocyte subpopulations. CONCLUSION: The seasonal variation in CD4+ T- lymphocyte counts demonstrated in three healthy individuals over almost 7 years is again of interest in light of renewed consideration of using surrogate tests, such as CD4+ T-lymphocyte counts, to screen for AIDS- like diseases that may be in the blood supply.  相似文献   
10.
An expanding and increasingly older population, a rising incidence of prostate cancer, and uncertainties regarding treatment effectiveness have made this disease a target of special concern. The natural history of the cancer must be a consequence of host-tumor interactions, but little is known for sure about this subject. The growth rate of the tumor is determined by many factors, including genetic instability. At present, tumor grade, volume, and ploidy are the most useful techniques for judging the growth rate and metastatic potential. Stage A1 tumors generally are indolent, whereas stage A2 tumors are more aggressive. The natural history of stage B lesions is not well documented. The author asks two questions (Is cure necessary in those in whom it may be possible? Is cure possible in those in whom it may be necessary?) and reviews the problems inherent in screening for prostate cancer at this time.  相似文献   
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