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1.
Radical neck dissection is a standard procedure carried out for the teatment of palpable nodes in the neck but if carried out electively in cases where there are no palpable nodes in the neck it is considered to be an overtreatment with its associated morbity. Lateral neck dissection was carried out on twenty patients who had T31 T4 lesion of the larynx and hypophar-vnx with NO neck. The dissection entails removal of Level II. III and IV nodes. Occult metastasis 80% and 85% respectively. The mean follow up was 13 monts. It appears from our study that elective lateral neck dissection is a promising and safe procedure and may be useful as an important prognostic tool in sampling the lymph nodes and predicting recurrences in the neck.  相似文献   
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OBJECTIVES: This study was designed to determine in a dog model of coronary thrombosis whether short-term eptifibatide (Ep) combined with low-dose plasminogen activator (rt-PA) inhibits platelet recruitment at sites of endothelial damage after normalization of platelet function. BACKGROUND: Ep plus reduced-dose rt-PA has not previously been shown to render a recanalized coronary artery resistant to platelet recruitment after normalization of platelet function. METHOD: Inhibition of platelet recruitment was studied by scanning electron microscopy (SEM) in a canine model of left anterior descending (LAD) thrombosis. In phase I treatment groups were: 1) Ep (n = 6); 2) Ep + rt-PA (n = 6); 3) rt-PA (n = 6); and 4) placebo (n = 4). Coronary blood flow was monitored and LAD segments excised for SEM after 90-min infusion of study drug. In phase II, dogs were randomized to Ep alone (n = 5) or to Ep + rt-PA (n = 5). Coronary blood flow was monitored during and 120 min after cessation of drug when platelet function had returned to normal and LAD segments were excised. RESULTS: All animals except placebo showed reflow. In phase I, SEM showed an absence of platelet aggregates with Ep alone and with Ep + rt-PA, but not with rt-PA alone. In phase II, SEM showed an intimal surface devoid of mural thrombus and platelet aggregates only in Ep + rt-PA treated arteries. Ep-alone treated arteries showed new platelet aggregates at sites of residual mural thrombus. CONCLUSIONS: Short-term infusion Ep plus low-dose rt-PA acutely neutralizes the ability of damaged endothelial surfaces to recruit new platelets by inhibiting platelet aggregation and eliminating residual mural thrombus.  相似文献   
3.
Finn AV  Saeed O  Virmani R 《Circulation research》2012,110(9):e64; author reply e65-e64; author reply e66
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4.
Production of carbon fibers (CF) using renewable precursors has gained importance particularly in the last decade to reduce the dependency on conventional petroleum-based precursors. However, pre-treatment of these renewable precursors is still similar to that of conventional ones. Little work is put into greener pre-treatments and their effects on the end products. This work focuses on the use of bio-cleaned lignin as a green precursor to produce CF by electrospinning. Bio-cleaned kraft lignin A (Bio-KLA) and uncleaned kraft lignin A (KLA) were used to explore the effect of bio-cleaning on the diameter and mechanical properties of lignin fibers and CF. The effect of electric field, lignin-to-poly(ethylene oxide) (PEO) ratio and PEO molecular weight (MW) were evaluated by 33 factorial design using Design of Experiment (DOE). The electrospinning process parameters were optimized to obtain a balance between high elastic modulus and small fiber diameter. The model predicted optimized conditions were 50 kV m−1 electric field, 95/5 lignin-to-PEO ratio and 1000 kDa MW of PEO. When compared to KLA, Bio-KLA CFs showed a 2.7-fold increase in elastic modulus, 2-fold increase in tensile strength and 30% decrease in fiber diameter under the same optimum conditions. The results clearly show that bio-cleaning improved the mechanical properties of lignin derived CF.

Waste lignin (KLA) and bio-cleaned lignin (Bio-KLA) precursors, used to produce parameter-optimized-electrospun carbon fibers showed improved mechanical properties for Bio-KLA.  相似文献   
5.
The two pivotal U.S. trials of drug-eluting stents do not establish the principle that these stents are superior to thin-strut bare-metal stents for preventing repeat revascularization in patients with diabetes. Neither study was adequately powered to make this determination. Moreover, both studies used thick-strut stents known to have high restenosis rates as controls. Low angiographic follow-up underestimates the true target lesion revascularization rate in the Polymer-Based Paclitaxel-Eluting Stent in Patients with Coronary Artery Disease (TAXUS-IV) trial because of the high incidence of silent ischemia in patients with diabetes. Optimal therapy for diabetic coronary disease should include a comprehensive approach directed toward metabolic normalization in addition to local stent-based therapy.  相似文献   
6.
A total of forty consecutive patients suffering from recurrent traumatic anterior shoulder instability underwent stabilisation with a glenoid based inferior capsular shift. The patients were followed up prospectively by an independent observer (JM) using the Constant-Murley score and objective evaluation of shoulder movement and strength with an isometric dynamometer. The mean follow-up period was 50 months (range, 2 to 6.8 years). Three patients (7.5%) suffered a repeat, high energy, traumatic dislocation following an early return to sports activities. "Cybex" testing documented a minimal average loss of external rotation movement (4.4 degrees) and strength (4.3%) with the arm in neutral, which was higher with the arm at 90 degrees of abduction (i.e., 13.7 degrees and 15.6%, respectively). The deficit in internal rotation strength was similarly lower in neutral position (2%), when compared to the deficit with the arm at 90 degrees of abduction (13.5%). There was no measurable loss of internal rotation motion. Our study supports the use of a glenoid based inferior capsular shift, as there is a low recurrence rate and minimal deficit in shoulder movement and strength.  相似文献   
7.
BACKGROUND: Live donor renal transplantation (LRT) now comprises more than 40% of all kidney transplants performed in the United States. Many patients on the cadaveric waiting list have a prospective live kidney donor. This study determines whether cadaveric donor renal transplantation (CRT) can demonstrate better outcomes than LRT. METHODS: From the United States Renal Data System registry, 31,909 adult recipients of a first-time kidney transplant from 1995 to 1998 were analyzed. Recipients were followed until December 31, 2000. RESULTS: CRT, more human leukocyte antigen (HLA) mismatches, increased donor age, cold ischemia time greater than 24 hr, African American recipient, and a history of diabetic nephropathy all increased the risk of graft failure, return to dialysis, and death. Nevertheless, in specific circumstances, CRT could provide better outcomes than LRT. For example, in recipients aged 18 to 59 years with a hypothetical live kidney donor aged 50 years and four HLA mismatches, the relative risk of graft loss with LRT is comparable or increased compared with CRT if the cadaveric kidney donor is much younger or with fewer HLA mismatches. On the other hand, for recipients aged 60 years or older, CRT never provides better outcomes than LRT. All analyses were adjusted for recipient race, gender, and history of diabetic nephropathy. There were no significant interactions among donor type, HLA mismatches, donor age, and cold ischemia time. CONCLUSIONS: The elderly recipient with an imminent LRT should never be offered CRT. A combination of recipient and donor factors can make CRT preferable to LRT in younger patients.  相似文献   
8.
Because much evidence implicates the dopamine transporter in the reinforcing effects of cocaine, development of potential medications for cocaine dependence has included the dopamine transporter as a target. The present overview covers progress in the drug development area regarding several classes of dopamine uptake inhibitors, with an emphasis on structure-activity relationships that enhance potency and selectivity at transporters for dopamine compared with those for serotonin or norepinephrine. The following categories of compounds are covered: tropane, benztropine, 1-[2-[bis(4-fluorophenyl)methoxy]ethyl]-4-(3-phenylpropyl)piperazine (GBR), methylphenidate, mazindol, and phencyclidine analogs. Activity at transporters as well as on behavior is highlighted.  相似文献   
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