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31.
Alex  Neil 《JAMA》2004,291(24):3017
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Firearms in the home and child safety   总被引:3,自引:0,他引:3  
One hundred fifty families who were seen in the pediatric outpatient clinics at The University of Texas Medical Branch, Galveston, were surveyed to learn about firearm possession in the home and its hazards to children. Thirty-eight percent of these families kept at least one gun in their home. Fifty-five percent of this group reported that the gun was loaded at all times, and 10% reported that the gun was kept loaded, unlocked, and within the reach of a child. We identified demographic characteristics of at-risk families and considered national statistics for gun safety. It was concluded that household firearms pose a significant risk to children and that intervention by physicians could help reduce this public health problem.  相似文献   
34.
During a 4-year period, 136 patients undergoing 152 carotid endarterectomies consented to be randomized to primary or saphenous vein patch closure of the arteriotomy. At operation, before randomization, careful assessment of arterial dimensions and anatomy was made. Patients who had an internal carotid artery (ICA) diameter less than 5 mm, arteriotomy extending more than 3 cm beyond the origin of the ICA, or tortuous or kinked ICAs were not randomized; they received obligatory vein patch closure (necessary in 20% cases). All patients were followed up every 3 months for 1 year and every 6 months thereafter with duplex scanning, ocular pneumoplethysmography, and neurologic assessment. The incidence of atherosclerotic risk factors was equal in the groups and all except one of the patients were male. Perioperative morbidity was not significantly different among those having primary closure (n = 60), saphenous vein patch closure (n = 62), and obligatory vein patch closure (n = 30). Operative time among patients having primary closure (122 +/- 4 minutes) was significantly less (p less than 0.001) than among those having saphenous vein patch closure (150 +/- 3 minutes). Three perioperative strokes were evenly distributed among the groups (2% for all procedures); no deaths and no acute postoperative occlusions occurred. Recurrent disease occurred in 12.9% of patients having saphenous vein patch closure compared with its occurrence in 1.7% of those having primary closure (p less than 0.05). However, most recurrences were moderate stenoses (25% to 50% diameter reduction), all were smooth-surfaced, and none required a second operation. All except one of the recurrences among those patients with saphenous vein patch closure were in the bulb and the origin of the ICA; two had evidence of regression. This finding suggested that thrombus layering in the dilated part of the saphenous vein patch reconstruction was the cause. This study demonstrates that in men with carotid arteries of predetermined minimal dimensions undergoing carotid endarterectomy routine saphenous vein patch closure does not produce superior results, is associated with a higher incidence of early recurrence, and increases operative time. In selected patients with anatomic risk factors for recurrent disease or acute postoperative occlusion, saphenous vein patch closure is appropriate.  相似文献   
35.
The urinary tract undergoes profound physiologic and anatomic changes during pregnancy that facilitate the development of symptomatic urinary tract infections in women with bacteriuria. While the adverse effects of asymptomatic bacteriuria on maternal and fetal health continue to be debated, it is clear that asymptomatic bacteriuria is the major risk factor for developing symptomatic urinary tract infection and that symptomatic infections are associated with significant maternal and fetal risks. Because the majority of symptomatic urinary tract infections develop in women with bacteriuria earlier in pregnancy, treatment of bacteriuria is undertaken to prevent symptomatic infections. All women should be screened at the first antenatal visit, which is reliably and inexpensively done with a dipstick culture. Short-course therapy is as effective as prolonged therapy and should be followed with a repeat culture to document clearing of the bacteriuria. Failure to eliminate bacteriuria with repeated therapy or recurrence with the same organism is indicative of renal parenchymal infection or a structural abnormality. All women with persistent bacteriuria or recurrent infection should have follow-up cultures and a complete urologic evaluation after delivery.  相似文献   
36.
Performance of same-day upper and lower endoscopy has many potential advantages, as it may reduce costs, shorten hospital stay, and expedite patient care, but its feasibility, efficacy, and potential have not been carefully defined. We report here our experience with a group of 87 patients who underwent same-day upper and lower endoscopy (174 procedures) over a 2-yr period at a tertiary care VA Hospital, compared with an alternate-day upper and lower endoscopy group of 50 patients (100 procedures) over the same time period. Most patients were elderly males. Common indications for endoscopy were occult or overt gastrointestinal bleeding, previous or concomitant history of pertinent pathology (i.e., polyps, ulcers), abdominal pain, diarrhea, or other symptoms, abnormal radiological studies, and iron deficiency anemia. Both groups required similar amounts of intravenous sedation. There were no complications in either group. In both groups, common positive findings were inflammation (i.e., colitis, esophagitis), benign neoplasms, diverticulae, peptic ulcer, and cancer. In both groups, only 2-6% had negative upper and lower endoscopy, whereas either one procedure was negative in 25% and 18% of cases, respectively. We conclude that the practice of same-day inpatient upper and lower endoscopy is feasible, has excellent diagnostic yield, even in the elderly, and carries no increased risks. When indicated, the practice of same-day upper and lower endoscopy should be encouraged.  相似文献   
37.
Twenty-five symptoms, signs, and abnormal investigations were looked for in 20 patients with clinically-definite myotonic dystrophy. Weakness of facial muscles, neck flexors, and arm external rotators was found in all patients (sensitivity = 100%). Arm external rotation has not been reported as a frequently involved muscle in previous clinical studies on myotonic dystrophy. Careful examination of muscle strength may therefore predict which patients may or may not carry the abnormal gene for myotonic dystrophy.  相似文献   
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Hydrogen peroxide, a reactive oxygen intermediate produced by activated neutrophils, has been shown to inhibit the response of human T lymphocytes to mitogens and alloantigens. Since hydrogen peroxide is known to react with iron and to induce lipid peroxidation, we compared the effects of hydrogen peroxide and a lipid peroxidation product, malondialdehyde, on the response of human peripheral blood mononuclear cells to T-cell mitogens. Peripheral blood mononuclear cells pretreated with 1 mmol/L of malondialdehyde, washed, and resuspended in fresh medium exhibited no inhibition of phytohemagglutinin responsiveness. Peripheral blood mononuclear cells treated in the same manner but with 200 mumol/L of hydrogen peroxide were inhibited by more than 95%. The addition of ferric edetate did not alter the inhibitory effects of 50 to 100 mumol/L of hydrogen peroxide, nor did the addition of deferoxamine, an iron chelator. These studies suggest that exogenous lipid peroxidation does not affect lymphocyte activation but that hydrogen peroxide has a direct inhibitory effect. Although monocytes are necessary for T-cell mitogenic responses, the effect of hydrogen peroxide was found to be directed at T lymphocytes. Exposure of T cells to a single dose of 200 mumol/L of hydrogen peroxide resulted in more than 71% suppression of the proliferative response measured 48 hours later, but the effect was spontaneously reversed by 72 to 96 hours. Repeated exposure of the cells to hydrogen peroxide resulted in continued inhibition of the proliferative response. These findings suggest that hydrogen peroxide produced by inflammatory phagocytic cells might be capable of suppressing the immune response of nearby T lymphocytes.  相似文献   
40.
Abdominal magnetic resonance imaging findings were reviewed in 46 patients with Gaucher disease. All patients had hepatosplenomegaly at the time of initial imaging. Splenic nodules were present in 14 patients (30%) and varied in signal intensity. These nodules were isointense on T1-weighted and hypointense on T2-weighted images. Splenic infarcts were seen in 15 patients (33%), and four of these patients (9%) also had subcapsular fluid collections. Both nodules and infarcts were present in the spleen in four patients (9%). Pathologic correlation was performed with specimens from two patients who underwent partial splenectomy. Focal areas of abnormal signal intensity were noted in the liver in nine patients (20%). They were either stellate or segmental, and may represent fibrotic septa with ischemic changes associated with aggregates of Gaucher cells. No changes were noted in the kidneys or abdominal lymph nodes.  相似文献   
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