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With use of 24-hour ambulatory electrocardiographic monitoring, the effect of 1 hour of cigarette smoking on cardiac rhythm in 73 patients with coronary heart disease was studied. Fifteen subjects had no arrhythmia; 37 subjects had fewer than 2 atrial or ventricular premature complexes (APCs or VPCs)/hour, with APCs possibly related to smoking in 2 and VPCs related to smoking in 1. Nineteen subjects had more than 2 VPCs/hour (range 4 to 368) and had 16 ± 29 VPCs/hour (± standard deviation) less during than before smoking (p <0.05), associated with an increase in heart rate of 4.6 ±6.8 beats/min (p <0.01). In none of the 9 subjects with unifocal VPCs did multiform beats develop during or after smoking, whereas 3 of 10 subjects with multiform VPCs had only unifocal beats during and immediately after smoking. In 1 of these 19 subjects, frequent APCs developed during smoking. One other subject had frequent APCs unaffected by smoking and another had sinoatrial block, which disappeared during smoking on 1 of 3 monitorings. In conclusion, no sustained or high-grade ventricular arrhythmia was provoked by smoking; although APCs may have been related to smoking in a few persons, the frequency and complexity of VPCs tended to be reduced in these subjects with coronary artery disease.  相似文献   
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OBJECTIVE--To determine the frequency of occurrence of mitral and aortic valvar regurgitation in rheumatic children in whom there was no evidence of carditis acutely or at an earlier attack. DESIGN--Colour flow Doppler imaging was used in a non-randomised study of sequentially admitted children who met the criteria for acute rheumatic fever without clinically evident carditis and patients in whom the disease was quiescent after a previous attack of rheumatic fever. Two separate control groups were used for comparison of the echocardiographic findings, and a group of patients with confirmed rheumatic carditis was included for comparison of acute phase and antistreptococcal reactants. SETTING--A general hospital with the only paediatric inpatient department in Qatar. PATIENTS--From November 1988 to October 1990, 11 children were studied during the acute rheumatic period. In seven additional children the disease was quiescent when they were studied 18 to 36 months after a documented episode of acute rheumatic fever in which there was no evidence of carditis. The control patients were all studied during the same period. MAIN OUTCOME MEASURE--Detection of mitral and aortic regurgitation in patients without clinical evidence of rheumatic carditis in the acute or quiescent stages of the disease. RESULTS--Mitral or mitral and aortic regurgitation was found in 10 of the 11 children studied in the acute rheumatic period. None had a murmur or other evidence of carditis. In all the cases studied the valvar insufficiency was mild. Four of the children studied late in the quiescent period had either aortic or mitral insufficiency by colour flow Doppler evaluation; two children who had previously had valvar insufficiency no longer showed this, and one child without positive findings in the acute phase remained without insufficiency. None of the non-rheumatic control subjects showed mitral or aortic regurgitation. CONCLUSIONS--Colour flow Doppler imaging is a useful method of identifying subclinical mitral and aortic valvar disease at all stages of rheumatic fever when carditis cannot be otherwise detected and is a valuable addition to current diagnostic criteria.  相似文献   
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The aim of this study was to evaluate the in vivo biodegradation and biocompatibility of three-dimensional (3D) scaffolds based on a hydroxyl-functionalized polyester (poly(hydroxymethylglycolide-co-ε-caprolactone), PHMGCL), which has enhanced hydrophilicity, increased degradation rate, and improved cell-material interactions as compared to its counterpart poly(ε-caprolactone), PCL. In this study, 3D scaffolds based on this polymer (PHMGCL, HMG:CL 8:92) were prepared by means of fiber deposition (melt-plotting). The biodegradation and tissue biocompatibility of PHMGCL and PCL scaffolds after subcutaneous implantation in Balb/c mice were investigated. At 4 and 12 weeks post implantation, the scaffolds were retrieved and evaluated for extent of degradation by measuring the residual weight of the scaffolds, thermal properties (DSC), and morphology (SEM) whereas the polymer was analyzed for both its composition ((1)H NMR) and molecular weight (GPC). The scaffolds with infiltrated tissues were harvested, fixed, stained and histologically analyzed. The in vitro enzymatic degradation of these scaffolds was also investigated in lipase solutions. It was shown that PHMGCL 3D-scaffolds lost more than 60% of their weight within 3 months of implantation while PCL scaffolds showed no weight loss in this time frame. The molecular weight (M(w)) of PHMGCL decreased from 46.9 kDa before implantation to 23.2 kDa after 3 months of implantation, while the molecular weight of PCL was unchanged in this period. (1)H NMR analysis showed that the degradation of PHMGCL was characterized by a loss of HMG units. In vitro enzymatic degradation showed that PHMGCL scaffolds were degraded within 50 h, while the degradation time for PCL scaffolds of similar structure was 72 h. A normal foreign body response to both scaffold types characterized by the presence of macrophages, lymphocytes, and fibrosis was observed with a more rapid onset in PHMGCL scaffolds. The extent of tissue-scaffold interactions as well as vascularization was shown to be higher for PHMGCL scaffolds compared to PCL ones. Therefore, the fast degradable PHMGCL which showed good biocompatibility is a promising biomaterial for tissue engineering applications.  相似文献   
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BACKGROUND/OBJECTIVE:

Several combination endoscopic therapies are currently in use. The present study aimed to compare argon plasma coagulation (APC) + adrenaline injection (AI) with hemoclips + AI for the treatment of high-risk bleeding peptic ulcers.

METHODS:

In a prospective randomized trial, 172 patients with major stigmata of peptic ulcer bleeding were randomly assigned to receive APC + AI (n=89) or hemoclips + AI (n=83). In the event of rebleeding, the initial modality was used again. Patients in whom treatment or retreatment was unsuccessful underwent emergency surgery. The primary end point of rebleeding rate and secondary end points of initial and definitive hemostasis need for surgery and mortality were compared between the two groups.

RESULTS:

The two groups were similar in all background variables. Definitive hemostasis was achieved in 85 of 89 (95.5%) of the APC + AI and 82 of 83 (98.8%) of the hemoclips + AI group (P=0.206). The mean volume of adrenaline injected in the two groups was equal (20.7 mL; P=0.996). There was no significant difference in terms of initial hemostasis (96.6% versus 98.8%; P=0.337), rate of rebleeding (11.2% versus 4.8%; P=0.124), need for surgery (4.5% versus 1.2%; P=0.266) and mortality (2.2% versus 1.2%; P=0.526). When compared for the combined end point of mortality plus rebleeding and the need for surgery, there was an advantage for the hemoclip group (6% versus 15.7%, P=0.042).

CONCLUSION:

Hemoclips + AI has no superiority over APC + AI in treating patients with high-risk bleeding peptic ulcers. Hemoclips + AI may be superior when a combination of all negative outcomes is considered.  相似文献   
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Retama raetam (RR) fruits are used in Saudi traditional medicine for the treatment of diabetes. Current study aimed at evaluating the potential and mechanisms of the antidiabetic activity of the RR methanolic extract in streptozotocin-induced diabetic rats. Oral LD50 of the extract was found to be 1995 mg/kg. The extract was administered once orally to STZ-diabetic rats at three dose levels; 100, 250 or 500 mg/kg/day for 4 consecutive weeks. RR extract at 250 or 500 mg/kg significantly lowered blood glucose levels at the 3rd and 1st week of treatment, respectively. Meanwhile, oral glucose tolerance test indicated that the same two doses significantly lowered glucose levels at 30 and 60 min after glucose challenge. Administration of RR extract at 500 mg/kg/day for 4 consecutive weeks significantly increased serum insulin level. In vitro studies indicated that the extract significantly inhibits glucose absorption by rat isolated intestine. The extract neither altered glucose uptake by rat isolated psoas muscle nor the activity of hepatic microsomal glucose-6-phosphatase. In conclusion, the methanolic extract of RR improves STZ-induced diabetes in rats. This can be attributed, at least partly, to stimulating pancreatic insulin release and reducing intestinal glucose absorption.  相似文献   
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Retinopathy of Prematurity (ROP) is one of the leading causes of bilateral blindness in childhood. Early detection and effective treatment can prevent blindness. Efficient and timely screening examination of the retina by an experienced ophthalmologist who deals with preterm neonates with ROP is the mainstay in the management of this disease. All neonatologists and pediatricians who care for these at-risk preterm neonates should also be aware of this timing. This practical guideline intends to provide guidance to ophthalmologists, neonatologists and allied health care professionals in Saudi Arabia on current indications for screening and management of retinopathy of prematurity to prevent or minimize subsequent complications. This practical guideline was led by the National Eye Health Program (NEHP) and Neonatology Services Improvement Program at Ministry of Health (MOH), furthermore it has been solicited and endorsed from both Saudi Ophthalmological Society (SOS) and Saudi Neonatology Society (SNS).  相似文献   
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