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91.
Diagnostic clinical findings of a new syndrome with night blindness, maculopathy, and enhanced S cone sensitivity 总被引:10,自引:0,他引:10
M F Marmor S G Jacobson M H Foerster U Kellner R G Weleber 《American journal of ophthalmology》1990,110(2):124-134
We studied eight patients who had night blindness, maculopathy (often cystoid), degenerative changes in the region of the vascular arcades, relatively mild visual field loss, and an unusual but characteristic electroretinogram. The dark-adapted electroretinogram showed no response to low-intensity stimuli that normally activate the rods, but large, slow responses to high-intensity stimuli. These large, slow waveforms persisted without change under light adaptation, and showed a striking mismatch to photopically balanced short and long wavelength stimuli (with sensitivity much greater to short than long wave-lengths). Since there is evidence from other studies that the electroretinogram and psychophysical responses represent hypersensitivity of short wavelength-sensitive (S or blue) cones, we propose that this disorder be called the enhanced S cone syndrome. There can be different degrees of severity in this syndrome, and progression appears to be slow. 相似文献
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To clarify the potential role of endothelin-1 (ET-1) in the pathogenesis of glaucoma, the endothelin receptors expressed in bovine trabecular meshwork (TM) and ciliary muscle (CM) were identified. TM and CM strips were subjected to ET-1 as well as to specific endothelin receptor antagonists. In both tissues BQ123, a specific ET-A receptor antagonist, substantially inhibited ET-1-induced contraction. BQ788, a specific ET-B receptor antagonist, showed only moderate effects. Both ET receptor types were detected in bovine TM and CM using Western blot analysis. ET-1 produced an increase in intracellular calcium in cultured TM cells. This effect was inhibited by BQ123, but not by BQ788. Thus, although both receptors are present, the ET-A receptor appears to play the predominant role in mediating contraction in both the TM and CM, while the ET-B receptor seems to contribute little to the overall ET-1 effect. 相似文献
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Hoeller S Bihl MP Zihler D Cogliatti S Ponzoni M Zettl A Went P Foerster A Hirschmann P Tzankov A Dirnhofer S 《Human pathology》2012,43(3):405-412
Aberrant expression of the antiapoptotic protein BCL (B-cell lymphoma)-2 in neoplastic germinal centers is one of the diagnostic hallmarks of follicular lymphoma. If BCL-2 cannot be detected by immunohistochemistry, the distinction between florid follicular hyperplasia and follicular lymphoma might become a diagnostic challenge. Most of those cases also lack the typical t(14;18), and the underlying pathophysiologic conditions of follicular lymphoma that lack BCL-2 protein expression are largely unknown. Here, we collected 18 BCL-2-negative follicular lymphoma cases from 5 different institutions. After restaining, 9 cases proved to be truly BCL-2 negative (6 follicular lymphoma grade 2, 2 follicular lymphoma grade 3a, and 1 follicular lymphoma grade 3b). In 4 additional cases, BCL-2 was very faint (all grade 2). Of the 9 BCL-2-negative follicular lymphoma cases, 2 were negative for CD10 (22%); all showed expression of BCL-6. Apoptotic level as determined by caspase 3 was the lowest in the BCL-2-positive follicular lymphoma group (15 ± 8 mm(2)), the highest in the normal/reactive group (n = 7, 60 ± 12 mm(2)) and very similar in the BCL-2 low follicular lymphoma and BCL-2-negative follicular lymphoma groups (25 ± 13 and 33 ± 19 mm(2), respectively), assuming an intermediate position between reactive follicles and BCL-2-positive neoplastic follicles (P < .001 [Kruskal-Wallis]). Also noted was a difference in proliferation fractions between the BCL-2-positive follicular lymphoma (27% ± 15%), the BCL-2 low follicular lymphoma (30% ± 20%) and the BCL-2-negative follicular lymphoma groups (30% ± 22%). Regarding the network of follicular dendritic cells, 8 (89%) of 9 cases from the BCL-2-negative subgroup showed disrupted, weakly developed networks, whereas all of the follicular lymphoma BCL-2 low-expression cases showed a well-defined and strongly developed follicular dendritic cell network. Among BCL-2-negative follicular lymphoma, BCL-2 and BCL-6 breaks were found in 1 case each, whereas in the follicular lymphoma BCL-2 low group, only 1 case with a BCL-6 break was recorded. No statistically significant result was achieved upon assessment of BCL-2α or BCL-2β RNA or the ratio of α/β isolated by real-time-polymerase chain reaction. Taken together, BCL-2-negative follicular lymphoma did not show a BCL-2 break on the genetic level and showed both increased apoptotic and proliferation rates compared with BCL-2-positive follicular lymphoma. In our series, BCL-6 breaks were infrequent in BCL-2-negative follicular lymphoma. 相似文献
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Andrea Mari Mohammad Abufaraj Beat Foerster Mehmet ?zsoy Alberto Briganti Morgan Rouprêt Pierre I. Karakiewicz Romain Mathieu David DAndrea Daher C. Chade Shahrokh F. Shariat 《Clinical genitourinary cancer》2018,16(3):e619-e627
Introduction
The purpose of the present study was to investigate the association of smoking with biochemical recurrence (BCR) and metastasis in radiation-recurrent prostate cancer (PCa) patients undergoing salvage radical prostatectomy (SRP).Patients and Methods
A total of 214 patients treated with SRP for radiation-recurrent PCa in 5 tertiary referral centers were included from January 2007 to December 2015. Kaplan-Meier analyses were used to assess the time to BCR and metastasis. Pre- and postoperative multivariable Cox proportional hazard regression models were fitted.Results
Overall, 120 (56.1%), 49 (22.9%), and 45 (21%) patients were never, former, and current smokers, respectively. Low-, medium-, and high-cumulative smoking exposure was registered in 59.8%, 16.4%, and 23.8% of cases, respectively. Patients with high cumulative smoking exposure had a significantly greater rate of a pathologic Gleason score of ≥ 8 (P = .01) and extracapsular extension (P = .004). Smoking status, cumulative smoking exposure, intensity, and duration were significantly associated with BCR-free survival (P < .001 for all). Smoking status, cumulative smoking exposure, and smoking intensity were significantly associated with metastasis-free survival (P = .03 for all). High cumulative smoking exposure was independently associated with BCR in both pre- (hazard ratio, 2.23; P = .001) and postoperative (hazard ratio, 1.64; P = .04) multivariable models adjusted for the effects of established clinicopathologic features. Smoking cessation did not affect either BCR- or metastasis-free survival (P = .56 and P = .40, respectively).Conclusion
High cumulative smoking exposure was associated with the biologic and clinical aggressiveness of PCa in patients treated with SRP for radiation-recurrent disease. Smoking is a modifiable risk factor that detrimentally affected the outcomes, even in patients with advanced PCa. 相似文献98.
By the end of the eighties mesh stents were implanted in malignant stenoses of the biliary and pancreatic ducts for the first time. In the following years, self-expanding as well as balloon-expandable mesh stents were increasingly implanted in malignant stenoses by radiologists or interventional gastroenterologists, either percutaneously or endoscopically retrograde. In randomized comparative studies different teams showed relevant advantages of this new type of prosthesis in comparison to the commonly used plastic stents. Especially the significantly lower rate of late complications and longer patency rates speak in favor of the mesh stents. The higher cost of the mesh stent makes it important to carefully select patients before implantation, to let patients with potentially longer survival time profit from the advantages of the procedure. Expandable mesh stents were successfully implanted in benign stenoses of the biliopancreatic ducts as well, although the lack of randomized comparative studies makes a final assessment difficult. Concluding from already presented results, there might be a new therapeutical option for selected patients with benign stenoses of the biliopancreatic ducts. 相似文献
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