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81.
Lymph node mapping has become an integral part of the management of melanoma and breast cancer with regard to both staging and treatment. We report our technique for lymphatic mapping and intraoperative lymphoscintigraphy applied to a patient with penile melanoma. This technique may improve the sensitivity of identifying the sentinel lymph node in patients with malignant penile lesions.  相似文献   
82.
AIM: To provide a simple method for assessing centile change based on the British 1990 growth reference. STATISTICAL METHOD: The change in SD score over a period of time has SD square root of 2(1-r), where r is the correlation between the first and second SD score. This leads to an SD score for centile change. DATA: Annual height measurements from 2 to 9 years for 318 children from the French longitudinal growth study. RESULTS: The correlations between heights at different ages are higher for shorter measurement intervals and at older ages. The chance of a child's height centile falling one centile band width is correspondingly smaller for shorter measurement intervals and at older ages. An increase in height measurement error reduces the correlations and dramatically increases the chances of centile crossing. CONCLUSIONS: Quantitative height monitoring based on centile change is provided for whole year periods between 2 and 9 years of age. Effective monitoring requires the measurement error to be as small as possible.  相似文献   
83.
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible.  相似文献   
84.
Children with cystic fibrosis have variable degrees of exocrine pancreatic insufficiency which, if untreated, is the main cause of fat malabsorption. The impact of pancreatic enzyme supplementation on fat digestion was measured in 41 children with cystic fibrosis, 11 healthy controls, and five children with mucosal diseases by a non-invasive test of intraluminal lipolysis using 13carbon (13C) labelled mixed triglyceride (1,3-distearyl, 2[13C] octanoyl glycerol). The children with cystic fibrosis without pancreatic supplements had a median (range) 13C cumulative percentage dose recovered over six hours (cPDR) of 3.1% (0-31.7), the controls 31.0% (21.8-41.1), and the subjects with mucosal disease 27.8% (19.7-32.5). In 23 subjects with cystic fibrosis the usual dose of pancreatic enzyme supplements increased the cPDR to a median of 23.9% (0-45.6), and twice the usual dose of enteric coated microspheres increased the cPDR to 31.1% (11.1-47.8). There was no significant difference between the median cPDR of normal controls and children with mucosal disease, but there was a highly significant difference between these groups and children with untreated cystic fibrosis. Thirteen children with cystic fibrosis had no 13C recovery in their breath without enzymes and 10 showed marked increases with regular enzymes. In eight children doubling the dose of enzymes caused no or minimal improvement. The mixed triglyceride breath test offers a simple, non-invasive way of assessing the need for pancreatic enzyme supplementation in children with cystic fibrosis and could be used to optimise treatment.  相似文献   
85.
Skin cancer is the most common and the most preventable form of cancer. Nonmelanoma skin cancers are associated with cumulative exposure to ultraviolet radiation, while melanoma is associated with intense episodes of ultraviolet exposure resulting in sunburns. Numerous risk factors are associated with the development of skin cancer. These include exposure to ultraviolet radiation; phenotypic factors such as skin type, eye and hair color, tendency to burn and tan, and having freckles and moles; a personal or family history of skin cancer; and occupational sun exposure. Primary prevention behaviors include applying SPF 15+ sunscreen 30 minutes before exposure, reapplying SPF 15+ sunscreen every 11/2 to 2 hours or after swimming or sweating, dressing in protective clothing, using shade, limiting exposure during peak sun hours, and avoiding artificial sources of ultraviolet radiation such as tanning beds. Secondary prevention behaviors include screening and early detection in combination with education on the primary prevention behaviors. Interventions designed to increase sun protective behaviors have resulted in increased knowledge and attitudes, but limited behavior change. And while skin cancer screenings have shown promising results, few studies have a follow-up component. Future studies should focus on developing effective strategies for making sun protective behaviors routine and determining the effectiveness of skin cancer screening. To inform approaches to the prevention and control of skin cancer, this paper will summarize key primary and secondary preventive behaviors, highlight primary and secondary prevention programs, and identify key unanswered questions in the area of skin cancer prevention and control.  相似文献   
86.
OBJECTIVES: To study the efficacy of otoacoustic emissions (OAEs) as a screening test for hearing impairment in children with acute bacterial meningitis. Hearing tests were performed before discharge from the hospital in an attempt to improve coverage and avoid delays in the diagnosis of postmeningitic hearing loss. METHODS: Children with bacterial meningitis were recruited from 21 centers. In the 48 hours before discharge from the hospital, all patients underwent a thorough audiologic assessment consisting of transient evoked OAEs, auditory brainstem responses (ABRs), otoscopy, and tympanometry. Hearing loss was defined as ABR threshold >/=30 dB. The results of OAE screening were compared with the gold standard of ABR threshold. RESULTS: Of 124 children recruited, we were able to perform both OAEs and ABRs on 110 children. Seven (6.3%) of the 110 children had ABR threshold >/=30 dB; 2 had sensorineural hearing loss and 5 had conductive hearing loss. At follow-up, hearing loss persisted in both cases of sensorineural hearing loss and no new cases were identified. All 7 children with hearing loss failed the OAE screening test. Ninety-four children with normal hearing thresholds passed the test, and 9 failed. Thus, the screening test had a sensitivity of 1.00 (95% confidence interval, 0.59 to 1.00), a specificity of 0.91 (0.85 to 0.97), a positive predictive value of 0. 44 (0.20 to 0.70), and a negative predictive value of 1.00 (0.96 to 1.00). CONCLUSIONS: OAE screening in children recovering from meningitis was found to be feasible and effective. The test was highly sensitive and reasonably specific. Inpatient OAE screening should allow early diagnosis of postmeningitic hearing loss and prompt auditory rehabilitation.  相似文献   
87.
Esophageal cancer has been associated with tobacco smoking, and nitrosamines are possible causative agents for this cancer. The present study investigated the metabolism of the tobacco carcinogens N'- nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1- butanone (NNK), and N-nitrosodimethylamine (NDMA), as well as the presence of xenobiotic-metabolizing enzymes in human esophageal tissues from individuals in the United States and Huixian, Henan Province, China (a high-risk area for esophageal cancer). All esophageal microsomal samples activated NNN and the metabolic rate was 2-fold higher in the esophageal samples from China than the USA. All microsomal samples activated NDMA. However, most of the microsomal samples did not activate NNK. Troleandomycin (an inhibitor of cytochrome P450 3A) decreased the formation of NNN-derived keto acid by 20-26% in the esophageal microsomes. The activities for NADPH: cytochrome c reductase, ethoxycoumarin O-deethylase, NAD(P)H: quinone oxidoreductase and glutathione S-transferase were present in the esophageal samples. Coumarin 7-hydroxylase (a representative activity for P450 2A6) activity was not detected in the esophageal microsomal samples. The activities for nitrosamine metabolism and xenobiotic- metabolizing enzymes were decreased (by 30-50%) in the squamous cell carcinomas compared with their corresponding non-cancerous mucosa. The presence of activation and detoxification enzymes in the esophagus may play an important role in determining the susceptibility of the esophagus to the carcinogenic effect of nitrosamines. Our results suggest that P450s 3A4 and 2E1 are involved in the activation of NNN and NDMA, respectively, in the human esophagus.   相似文献   
88.
A 54-year-old man was treated with weekly 24-h infusion of high-dose 5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon cancer. At first, he tolerated the treatment well and no significant toxicity was identified. After a total of eight courses of treatment, a stable disease was observed, but mild shortness of breath was found on occasion. The patient had no previous history of cardiac disease and the heart performance assessed by left ventricular ejection fraction before treatment was normal. Unfortunately, acute pulmonary edema with lethal cardiogenic shock occurred during the ninth course of treatment, in spite of intensive medical treatment. The chest X-ray showed extreme cardiomegaly. Repeated assessment of his heart function by echocardiogram and ventricular ejection fraction revealed a very poor cardiac performance. Toxic cardiogenic shock during weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin is extremely rare. To the best of our knowledge, no case has been reported in the English literature. We report a case and the relevant literature about the incidence, clinical picture and possible pathophysiology on 5-fluorouracil-related cardioxicity is reviewed.   相似文献   
89.
Polygonum multiflorum stilbeneglycoside (PMS) is a water-soluble fraction of Polygonum multiflorum Thunb. , one of the most famous tonic traditional Chinese medicines, that has protective effects on the cardiovascular system. The purpose of the present study is to elucidate the effects of PMS on macrophage-derived foam cell functions and the reduction of severity of atherosclerosis in hypercholesterolemic New Zealand White (NZW) rabbits. NZW rabbits were fed for 12 weeks with a normal diet, a high cholesterol diet, or a high cholesterol diet associated with irrigation with different doses of PMS (25, 50, or 100 mg/kg). Treatment of NZW rabbits fed with high cholesterol diet with 100 mg/kg PMS attenuated the increase in plasma cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and plasma triglyceride. Treatment with 50 and 100 mg/kg PMS caused 43% and 60% decrease in atherosclerotic lesioned area ratio to total surface area, respectively. In U937 foam cells, PMS could decrease the high expression of intercellular adhesion molecule (ICAM)-1 protein and the vascular endothelial growth factor (VEGF) protein levels in the medium induced by oxidized lipoprotein when analyzed by flow cytometry. The results proved that PMS is a powerful agent against atherosclerosis and that PMS action could possibly be through the inhibition of the expression of ICAM-1 and VEGF in foam cells.  相似文献   
90.
Complications from improperly placed biliary stents are not uncommon. Free loose wires from the ends of an uncovered stent can irritate and damage adjacent mucosal surfaces. Effective management can be achieved via percutaneous placement of a second stent to alter the orientation of the original stent.  相似文献   
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