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21.
We report a case of unilateral cataract with a posterior located central opacity greater than 3 mm in diameter, which resolved without surgical intervention in an otherwise healthy child. 相似文献
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ADAMTS4 and its proteolytic fragments differentially affect melanoma growth and angiogenesis in mice
Nithya Rao Zhiyuan Ke Hongrui Liu Chao‐Jin Ho Saran Kumar Wei Xiang Yizhun Zhu Ruowen Ge 《International journal of cancer. Journal international du cancer》2013,133(2):294-306
The metalloproteinase ADAMTS4 (ADAMTS, a disintegrin‐like and metalloproteinase with thrombospondin motif)/aggrecanase‐1 is highly expressed in cartilage and has been implicated in human arthritis. Although abundantly expressed in many types of cancer, its role in cancer remains unknown. In this work, we demonstrate for the first time that full‐length ADAMTS4 and its catalytically more active N‐terminal 53 kDa autocatalytic fragment both promote B16 melanoma growth and angiogenesis in mice. In contrast, overexpression of its catalytically inactive E362A mutant or truncated fragments containing only the C‐terminal ancillary domains suppresses melanoma growth and angiogenesis under similar conditions. Structure–function mapping revealed that the single thrombospondin‐type 1 repeat domain is essential and sufficient for the antitumorigenic activity displayed by the catalytically inactive ADAMTS4 isoforms. Suppression of tumor growth and angiogenesis in mice is accompanied by a significant increase in tumor cell apoptosis, whereas tumor cell proliferation is not affected. Importantly, we identified and demonstrated the presence of novel proteolytic fragments of ADAMTS4 containing essentially only the C‐terminal ancillary domains in cultured cells, and also in human cancer tissues, coexisting with full‐length and catalytically active N‐terminal fragments. The contrasting functions toward tumor growth in mice by the wild‐type proteinase and its catalytically inactive mutant correlate with their contrasting influences on angiogenesis signaling pathway molecules in B16 melanoma in mice. Our results suggest a complex role for ADAMTS4 in cancer with the functional balance of protumorigenic and antitumorigenic isoforms likely to act as an important parameter in determining the net influence of this metalloproteinase on tumor growth in vivo. 相似文献
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Mohammad Mozafar Khashayar Atqiaee Hamidreza Haghighatkhah Morteza Sanei Taheri Ali Tabatabaey Saran Lotfollahzadeh 《Lasers in medical science》2014,29(2):765-771
Endovenous laser therapy (EVLT) for greater saphenous vein (GSV) insufficiency is a relatively new method of treatment only recently made available in Iran. This is the first long-term randomized trial comparing EVLT with high ligation of saphenous vein (HLS) in the Iranian population. Sixty-five patients met the inclusion criteria and were divided into homogenous treatment groups of EVLT (n?=?30) or HLS (n?=?35). Clinical severity, etiology, anatomy, pathophysiology (CEAP) classification and Aberdeen Varicose Vein Symptom Severity Scores (AVSS) were used to determine disease severity and symptoms before and after the procedure in both groups. Outcome was measured by the rate of recurrence as shown in Doppler ultrasonography evaluation. Follow-up was conducted 1 week and 3, 6, 12, and 18 months after the intervention. The occlusion rate of GSV was similar in both groups (93.6 % for EVLT, 88.3 for HLS) at 18 months of follow-up. The median CEAP score showed a dramatic decrease in both groups after 1 week which was sustained for the rest of the study. The Aberdeen Varicose Vein Symptom Severity score was significantly lower in the EVLT group at 12 and 18 months of follow-up. There was no significant difference in patient satisfaction in both groups. Our findings show that EVLT may offer a better long-term relief of symptoms. This, alongside its better cosmetic outcome, and less invasive anesthesia requirements may make it the favorable choice for treatment of GSV insufficiency. 相似文献
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R K Saran K Bhandari V S Narain R C Ahuja V K Puri R Thakur S Dwivedi M Hasan 《International journal of cardiology》1990,28(2):209-213
We report the results of a randomized controlled trial of intravenous streptokinase in a subset of patients with unstable angina. Seventy-six patients were admitted with prolonged (more than 20 minutes) angina at rest of less than 3 weeks onset. Fifty-two patients continued to have more than 3 episodes of prolonged angina in 48 hours on medical therapy with metoprolol, isosorbide dinitrate, nifedipine and intravenous nitroglycerin. Forty-eight patients consented to enter the study and were randomized into two groups. The first group, of 24 patients, received 1.5 million units of streptokinase infusion and the second group, also of 24 patients, received a placebo. Pain relief within 48 hours was achieved in 19/24 (79.1%) patients after streptokinase infusion as compared to 9/24 (37.5%) of the controls (P less than 0.05). Approximately 90% (17/19) of patients responding to streptokinase therapy were relieved of chest pain within the first six hours as against none in the controls. The incidence of acute myocardial infarction within six months was 12.5% (3/24) in those receiving streptokinase and 25% (6/24) in the controls. Mortality at six months stood at 8.33% (2/24) in the treated patients and 16.6% (4/24) in the controls. Intravenous streptokinase thus appears to be of benefit in patients with angina at rest of recent onset which does not respond to conventional medical therapy. 相似文献
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Short-term (48 hours) versus long-term (7 days) antibiotic prophylaxis for permanent pacemaker implantation 总被引:5,自引:0,他引:5
Dwivedi SK Saran RK Khera P Tripathi N Kochar AK Narain VS Puri VK 《Indian heart journal》2001,53(6):740-742
BACKGROUND: Infection following permanent pacemaker implantation is a dreaded complication. Antibiotic prophylaxis for 1-10 days at the time of implant has been used in the past but there is no consensus regarding its duration. We carried out a prospective, randomized study of two durations of antibiotic prophylaxis to determine which one was more effective. METHODS AND RESULTS: One hundred and seventy-eight patients undergoing permanent pacemaker implantation for the first time were randomized to receive short duration (group A, n = 8 8) or longer duration (group B, n = 90) antibiotic prophylaxis for 2 days and 7 days, respectively. Patients in both groups received cloxacillin 2 g 2 hours prior to the procedure followed by ampicillin and cloxacillin (50 mg/kg/day in 4 divided doses) and gentamicin (3 mg/kg/day in 2 divided doses) for the respective duration. Patients were followed up for 1-17.3 months (9.3 +/- 1.8 months) in group A and 1-16.5 months (8.9 +/- 2 months) in group B. One patient in group B had an infection at the pacemaker site and two patients in each group had to undergo reimplantation due to pus in the pocket. There was no significant difference in the primary end-point in both groups. CONCLUSIONS: A short course (48 hours) of antibiotic prophylaxis following permanent pacemaker implantation is as effective as a longer course (7 days). 相似文献
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Raymond K. Hsu Charles E. McCulloch Michael Heung Rajiv Saran Vahakn B. Shahinian Meda E. Pavkov Nilka Ríos Burrows Neil R. Powe Chi-yuan Hsu 《Clinical journal of the American Society of Nephrology》2016,11(1):14-20