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61.
62.
TR Ekmekci† A Koslu† D Sakiz‡ 《Journal of the European Academy of Dermatology and Venereology》2005,19(3):355-356
Juvenile colloid milium is extremely rare, has its onset before puberty, may be inherited, may be caused by ultraviolet light, and is thought to result from the degeneration of keratinocytes. We report a 7-year-old girl with juvenile colloid milium. To the best of our knowledge this is the first reported case in Turkey. 相似文献
63.
64.
MT Britto JM Garrett MA Dugliss CW Daeschner CA Johnson MW Leigh JM Majure WH Schultz TR Konrad 《Pediatrics》1998,101(2):250-256
OBJECTIVE: To determine the prevalence and age of onset of common risky behaviors such as smoking and sexual activity in teens with cystic fibrosis and those with sickle cell disease and to compare their behaviors with those of adolescents in the general population. DESIGN: Survey. SETTING: All five major pediatric tertiary care centers in North Carolina (study participants with sickle cell disease or cystic fibrosis) and North Carolina public schools (comparison population). PARTICIPANTS: Three hundred twenty-one adolescents with cystic fibrosis or sickle cell disease aged 12 to 19 years (mean age, 15.6 years; 49% female). Demographically matched comparison teens for each group were selected from 2760 in-school adolescents (mean age, 16.0 years; 51% female). MAIN OUTCOMES MEASURES: Prevalence of tobacco and marijuana use, alcohol use, sexual intercourse, sexually transmitted diseases, seat belt use, weapon carrying, and age of onset of these behaviors. RESULTS: Chronically ill teens reported significantly less lifetime and current use of tobacco, marijuana, and alcohol; less sexual intercourse; less weapon carrying, less drunk driving, and more seat belt use than their peers. Nonetheless, 21% of the teens with cystic fibrosis and 30% of those with sickle cell disease had smoked; sexual intercourse was reported by 28% and 51%, respectively. Age of onset of these behaviors was frequently older for the chronically ill teens. CONCLUSION: Teens with cystic fibrosis or sickle cell disease took more potentially damaging health risks than might be expected, although the prevalence was lower than reported by their peers. Future longitudinal studies should examine the relationships between chronic illness, physical and psychosocial maturation, and risky behavior. Screening for psychosocial issues, including risky behaviors, should be incorporated into the routine health care of chronically ill teens. 相似文献
65.
TR Puoane GD Hughes J Uwimana Q Johnson WR Folk 《African journal of traditional, complementary, and alternative medicines》2012,9(4):495-502
The study explored the perceptions, knowledge and attitudes of patients, health workers and traditional healers about the use of traditional medicine and Anti Retroviral Therapy (ART). The study explored the perceptions, knowledge and attitudes of patients, health workers and traditional healers about the use of traditional medicine and Anti Retroviral Therapy (ART), using an exploratory qualitative design in two provinces of South Africa: an urban township health facility in the Western Cape, and a rural district hospital in KwaZulu-Natal (KZN) with antennal HIV rate of 32% and 28%''respectively. In-depth interviews were conducted with 14 participants: six HIV patients on ART and using Traditional Medicine(TM), two doctors, two nurses and four traditional healers. Two focus group discussions -one at each site - were held with community health workers who work with HIV-positive patients (Western Cape [5] and in KZN [4]). Patient said to have used Traditional Healing Practices (THP) before they were diagnosed with HIV, and some who have been diagnosed with HIV continue using TM in conjunction with ART and/or Cotrimoxazole prophylaxis. Patients preferred not to disclose THP to health professionals because of lack of support and understanding. Patients utilize THP because of family expectations, privacy and confidentiality, especially when they have not disclosed their HIV status. Healthcare professionals had strong negative opinions about THP, especially for HIV-positive patients. Traditional healers supported the patient''s rationale for THP use. This study revealed a need to better understand factors involved in patients'' choosing to use THP concurrently with ART. 相似文献
66.
Background
Upper gastrointestinal bleeding (UGIB) is a common emergency medical condition that may require hospitalization and resuscitation, and results in high patient morbidity. Upper gastrointestinal endoscopy is the preferred investigative procedure for UGIB because of its accuracy, low rate of complication, and its potential for therapeutic interventions.Objective
To determine the endoscopic findings in patients presenting with UGIB and its frequency among these patients according to gender and age in Lacor hospital, northern Uganda.Methods
The study was carried out at Lacor hospital, located at northern part of Uganda. The record of 224 patients who underwent endoscopy for upper gastrointestinal bleeding over a period of 5 years between January 2006 and December 2010 were retrospectively analyzed.Results
A total of 224 patients had endoscopy for UGIB which consisted of 113 (50.4%) males and 111 (49.6%) females, and the mean age was 42 years ± SD 15.88. The commonest cause of UGIB was esophagealvarices consisting of 40.6%, followed by esophagitis (14.7%), gastritis (12.6%) and peptic ulcer disease (duodenal and gastric ulcers) was 6.2%. The malignant conditions (gastric and esophageal cancers) contributed to 2.6%. Other less frequent causes of UGIB were hiatus hernia (1.8), duodenitis (0.9%), others-gastric polyp (0.4%). Normal endoscopic finding was 16.1% in patients who had UGIBConclusions
Esophageal varices are the commonest cause of upper gastrointestinal bleeding in this environment as compared to the west which is mainly peptic ulcer disease. 相似文献67.
大丁草中抗菌活性成分的研究Ⅳ 总被引:1,自引:0,他引:1
从秋季采收的菊科植物大丁草Gerbera anandria(L.)Sch Bip.全草中共分出十三种成分。本文报道其中三个新化合物的结构鉴定.它们分别是3,8-dihydroxy-4-methoxy-coumarin(ⅪⅩ),3,8-dihydroxy-4-methoxy-2-oxo-2 H-1-benzopyran-5-carboxylic acid(ⅩⅦ),和5,8-dihydroxy-7-(4-hydroxy-5-methyl-coumarin-3-)-coumarin(ⅩⅪ)。 相似文献
68.
Gelzleichter TR; Bermudez E; Mangum JB; Wong BA; Janszen DB; Moss OR; Everitt JI 《Toxicological sciences》1999,49(1):93-101
The present study was designed to determine whether pleural fiber burdens
or subchronic pleural fibroproliferative and inflammatory changes can help
explain the marked interspecies differences in pleural fibrosis and
mesothelioma that are observed following long-term inhalation of RCF-1
ceramic fibers by rats and hamsters. Fischer 344 rats and Syrian golden
hamsters were exposed to RCF-1 for 4 h per day, 5 days per week, for 12
consecutive weeks. Lung and pleural fiber burdens were characterized during
and after exposure. For all time points, approximately 67% of fibers
associated with lung tissues from both rats and hamsters were longer than 5
microns in length. In comparison, fibers longer than 5 microns recovered
from the pleural compartment, following a 12-week exposure and 12 weeks of
recovery, accounted for 13% (hamsters) and 4% (rats) of the distribution.
In the 12 weeks after the cessation of exposure, the number of fibers
longer than 5 microns in length remained constant in the hamster at
approximately 150 fibers per cm2 pleura. This was 2 to 3 times the
corresponding fiber surface density in the rat. Significant pulmonary and
pleural inflammation was detected at all time points and for both species.
DNA synthesis by pleural mesothelial cells was quantified by
bromodeoxyuridine uptake following 3 days of labeling. Labeling indices
were higher in hamsters than in rats, both for RCF-1-exposed and filtered
air-control animals and was highest for the parietal surface of the pleura.
Significantly greater collagen deposition was measured in the visceral
pleura of hamsters 12 weeks post-exposure but was not significantly
elevated in rats. These findings demonstrate that subchronic inhalation
exposure to RCF-1 induces pleural inflammation, mesothelial-cell turnover,
pleural fibrosis, and an accumulation of fibers with a length greater than
5 microns in the hamster. The accumulation of long fibers in the pleural
space may contribute to the pathology observed in the hamster following
chronic inhalation of RCF- 1, whereas the presence of short, thin fibers
may play a role in the acute-phase biological response seen in both
species.
相似文献
69.
Hong HL; Devereux TR; Melnick RL; Eldridge SR; Greenwell A; Haseman J; Boorman GA; Sills RC 《Carcinogenesis》1997,18(4):783-789
Isoprene is the 2-methyl analog of 1,3-butadiene, a genotoxic and
carcinogenic compound in rats and mice. Male B6C3F1 mice were exposed to 0,
2200 or 7000 ppm isoprene by inhalation (6 h/day; 5 days/week) for 26
weeks. Following a 26-week recovery period, an increased incidence of
Harderian gland (HG) neoplasms was observed at both concentrations. The
present study was designed to characterize genetic alterations in the K-ras
and H-ras protooncogenes in HG neoplasms. Mutations in K-ras and H-ras were
identified by single-strand conformational analysis and direct sequencing
of polymerase chain reaction (PCR) amplified DNA, isolated from
paraffin-embedded sections of HG neoplasms. A higher frequency of ras
mutations, in particular K- ras mutations, was detected in isoprene-induced
neoplasms than in 1,3- butadiene-induced or control HG neoplasms. All of
the isoprene-induced HG neoplasms exhibited activated K-ras (60%) or H-ras
(40%) mutations. In contrast, ras mutations were detected in 69% of HG
neoplasms from 1,3-butadiene exposed mice (14% K-ras and 55% H-ras) and in
56% of HG neoplasms obtained from control B6C3F1 mice (8% K-ras and 48%
H-ras). The predominant mutations in isoprene-induced HG neoplasms, but not
in previously or newly analysed 1,3-butadiene-induced HG neoplasms,
consisted of A-->T transversions (CAA-->CTA) at K-ras codon 61
(15/30) and C-->A transversions (CAA-->AAA) at H-ras codon 61 (8/30).
Two- thirds of the K-ras CTA mutations were detected in HG neoplasms from
the 2200 ppm exposure group while one-third was present in the 7000 ppm
group. Isoprene-induced HG neoplasms with K-ras or H-ras mutations had an
elevated proliferating cell nuclear antigen (PCNA) index, compared to
spontaneous HG neoplasms without ras mutations. The high frequency and
specificity of the ras mutation profile suggest that ras protooncogene
activation contributes to isoprene-induced HG tumorigenesis.
相似文献
70.
Metabolism of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) by human cytochrome P4501B1 总被引:1,自引:1,他引:1
Cytochrome P4501B1 (CYP1B1) is the most recently identified member of the
dioxin-inducible CYP1 family. CYP1B1 is constitutively expressed in most
human tissues, including colon and breast, and can activate numerous
chemically diverse carcinogens. We evaluated the metabolism of the dietary
heterocyclic amine carcinogen 2-amino-1-methyl-6-
phenylimidazo[4,5-b]pyridine (PhIP) by microsomes from yeast expressing the
human CYP1B1 protein. PhIP metabolites were analysed by HPLC with
fluorescence and absorbance detection. We found that human CYP1B1
metabolizes PhIP to three products: N2-OH-PhIP, a mutagenic activation
product; 4'-OH-PhIP, a detoxification product; and 2-OH-PhIP, the mutagenic
potential of which is unknown. Metabolite identity was confirmed by
co-elution with authentic standards and synchronous fluorescence
spectroscopy. The identity of the 2-OH-PhIP standard was additionally
confirmed by mass spectrometry. Kinetic studies of the formation of
N2-OH-PhIP, 4'-OH-PhIP and 2-OH-PhIP by CYP1B1 indicated apparent Km values
of 5.7 +/- 1.3, 2.2 +/- 0.5 and 1.3 +/- 0.2 microM, respectively. Apparent
turnover rates were 0.40 +/- 0.03, 0.93 +/- 0.02 and 0.04 +/- 0.00 nmol
product/min nmol P450, respectively. At saturating levels of substrate,
CYP1B1-mediated formation of the non- mutagenic metabolite 4'-OH-PhIP was
favored two-fold over that of the mutagenic metabolite, N2-OH-PhIP and
>10-fold over that of 2-OH-PhIP. The formation of N2-OH-PhIP, a potent
mutagen implicated in the etiology of human colon and breast cancer,
indicates that CYP1B1 may play an important role in PhIP-mediated
carcinogenesis.
相似文献