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排序方式: 共有1182条查询结果,搜索用时 9 毫秒
1.
Milos Jesenak MD PhD Peter Banovcin MD PhD Zuzana Rennerova MD PhD Lubica Jakusova MD PhD Zuzana Havlicekova MD PhD Vladimir Pohanka MD PhD MPH FCCP Maria Pia Villa MD PhD Roberto Ronchetti MD PhD 《International journal of dermatology》2009,48(9):941-946
Background The atopy patch test (APT) is no longer an experimental method; it is increasingly being used as a standard diagnostic tool for the characterization of patients with aeroallergen- and food-triggered disorders. Some technical aspects of this test still remain to be answered. We aimed to study the reproducibility of this test over time in the general child population.
Methods In a general population of 118 children, we investigated the reproducibility of duplicate APTs with four food allergens in their native form, which were repeated at set intervals from the first test: 7 days (group 1), 14 days (group 2), and 21 days (group 3).
Results We observed very poor reproducibility on both sides of the back in all three studied subgroups. The reproducibility rates and Cohen's κ values did not improve when we did not consider the side of the back. There were no differences in the prevalence of atopy between the subjects with reproducible and nonreproducible APT results. All three groups studied showed no difference in the prevalence rates of atopy. There was no relationship between APT and skin prick test positivity for the same allergen. Questionnaire-derived data about previous food-related reactions did not help in the evaluation of the doubtful nonreproducible APT results with food allergens.
Conclusions Our results show that the reproducibility of food APTs is poor and unsatisfactory over time, and there is an urgent need for the development of optimal, stable, and good-quality APT testing substances. 相似文献
Methods In a general population of 118 children, we investigated the reproducibility of duplicate APTs with four food allergens in their native form, which were repeated at set intervals from the first test: 7 days (group 1), 14 days (group 2), and 21 days (group 3).
Results We observed very poor reproducibility on both sides of the back in all three studied subgroups. The reproducibility rates and Cohen's κ values did not improve when we did not consider the side of the back. There were no differences in the prevalence of atopy between the subjects with reproducible and nonreproducible APT results. All three groups studied showed no difference in the prevalence rates of atopy. There was no relationship between APT and skin prick test positivity for the same allergen. Questionnaire-derived data about previous food-related reactions did not help in the evaluation of the doubtful nonreproducible APT results with food allergens.
Conclusions Our results show that the reproducibility of food APTs is poor and unsatisfactory over time, and there is an urgent need for the development of optimal, stable, and good-quality APT testing substances. 相似文献
2.
3.
Dara L. Hoffman James A. Owen Milos Chvapil 《Experimental and molecular pathology》1983,39(2):154-162
β-Aminopropionitrile as free base (BAPN) was applied onto the incised or intact skin of rats at the dose of 5, 20, 100, and 200 μl for 9 days, twice daily. Breaking strength of the skin wound or intact skin was significantly reduced at doses of 20 μl and higher; body weight growth was significantly retarded at the two highest dosages. It is concluded that at a given dose (20 μl) collagen polymerization (evaluated by reduced breaking strength and increased extractability of collagen) was specifically inhibited by BAPN. Furthermore, no evidence of topical or general toxic effects were observed, as reflected in histology, body weight growth, and behavior of the rats. Acute LD50 of BAPN base and fumarate, administered either ip or topically, was determined in mice. While BAPN base in ip administration shows LD50 of 1.15 g/kg, in cutaneous application it is more than 12.8 g/kg. It is suggested that topically applied BAPN base is percutaneously absorbed and affects collagen polymerization in the skin and adjacent tissues. 相似文献
4.
Efficacy and safety of imatinib mesylate in advanced gastrointestinal stromal tumors 总被引:1,自引:0,他引:1
5.
Welzl-Hinterkörner E Thölen H Stürmer J Opravil M Bernauer W 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,96(2):87-91
Background: Cystoid macular edema (CME) in AIDS patients with inactive cytomegalovirus (CMV) retinitis is an uncommon but potentially
sight-threatening complication. The pathogenesis of CME in these patients is unclear. This study tries to identify possible
risk factors by analyzing the charts of five patients.
Methods: Ten eyes of 5 patients that finally developed CME were followed for an average of 18 months. The initial retinal lesions,
their response to antiviral treatment, the development of CME, and the patients' immune status were prospectively monitored.
Results: CMV retinitis was diagnosed at a median CD4+ count of 3 cells/mm3 (range 0–11). All eyes responded to the initial systemic anti-viral treatment. At the onset of CME, CMV retinitis was controlled
by antiviral maintenance therapy in all patients [ganciclovir (n = 2), cidofovir (n = 2), foscarnet (n = 1)]. The median time between diagnosis of CMV retinitis and onset of CME was 11.5 months (range 5–24). Development of CME
was associated with significant visual loss: acuity ranged from 0.05 to 0.7 when CME was first noticed, compared to 0.8–1.25
at diagnosis of CMV retinitis. Duration of inflammation, size or zone of retinal necrosis did not favor the development of
CME, neither did the antiviral therapy. A weak correlation of CME development and immune status (expressed as increase of
CD4+ cells) was found. Due to systemic corticosteroids CME resolved.
Conclusions: CME is a new visual threat to AIDS-patients with CMV retinitis whose immune status improved under the latest combined antiretroviral
therapy. Therapy with oral corticosteroids may positively influence this condition.
相似文献
6.
Jaussi A Savcic M Delabays A Kappenberger L 《Echocardiography (Mount Kisco, N.Y.)》1996,13(3):281-286
Background: Exercise echocardiography (EE) is being used increasingly as an investigative technique now that dynamic images can be captured digitally. Its equivalent reliability with scintigraphic methods has been demonstrated in a hospital setting. This study analyzes its impact on daily practice. Materials and Methods: Standardized progressive stress was produced by supine bicycle ergometry. Echocardiographic images of complete cardiac cycles were obtained in standard apical and parasternal short-axis views before, during, and after maximum effort, and digitized for simultaneous analysis of synchronized images at rest and during exercise. Two hundred sixteen patients (175 men and 41 women; mean age 58 ± 10 years) were studied. Results: Image quality was suboptimal in 4 cases. In the remaining 212 cases, ischemia was detected in 91 cases, and the test was negative in 114 cases and doubtful in 7 cases. Control by selective coronary angiography, as indicated by the clinical situation, was performed in 52 cases. In this particular group, EE showed 87% sensitivity, which is significantly higher than the 59% recorded for conventional exercise testing (P > 0.0001). Conclusions: EE by bicycle ergometer in the supine position is a valid, noninvasive investigative technique that can be used in an outpatient situation (feasibility 95%) since it is readily available. Its value appears to be greatest in cases in which exercise ECG is not conclusive. A negative result enables the initial cardiologist to reassure the patient immediately, which has been demonstrated in the literature to have favorable prognostic value. 相似文献
7.
Allen L Seligson Brian K Campion Jason W Brown Ron C Terry Renata Kucerova Martina Bienova Marian Hajduch Milos Sovak 《Drug development research》2003,59(3):292-306
Nonsteroidal antiandrogens (AA) cannot be topically used for androgenetic alopecia (AGA) because of systemic resorption. A new class of androgen receptor (AR) suppressors designed for safe topical treatment of AGA was synthesized from (3‐amino‐2‐hydroxy‐2‐methyl‐N‐(4‐nitro‐3‐trifluoromethyl)phenyl) propanamide (BP‐34), to contain perfluoroalkyl moieties. The trifluoromethyl derivative (fluridil) at 10 μM decreased expression of the AR in LNCaP human cells by 95%, its serum half‐life was 6 h; it decomposes hydrolytically to BP‐34 and trifluoroacetic acid. Acute intraperitoneal maximum tolerated dose (MTD) of fluridil in mice is 270–300 mg/kg/d and the subacute MTD is 450 mg/kg/d. The oral LD50 in mice was 2,872 mg/kg in males, 2,232 mg/kg in females, and >2,500 mg/kg in rats. Fluridil solution in isopropanol was not cutaneously absorbed in rabbits, did not sensitize or show any phototoxic or photoallergic effects on guinea pig skin, and demonstrated no skin irritation potential in rabbits and humans. Fluridil solid induced only slight and reversible eye irritancy in rabbits and displayed no cytotoxicity to rabbit corneal fibroblasts in vitro. Fluridil demonstrated no significant mutagenicity potential by Ames method. In a double‐blind study, 43 males with AGA, Norwood grade II to Va, used topical 2% fluridil in isopropanol or the vehicle daily for 12 months. Anagens (growing hairs) increased in the fluridil group from 76% to 89%. All hematological and biochemistry values remained within normal range, including testosterone, which varied but seasonally. No fluridil or its decomposition product (BP‐34) was detected in serum. No adverse side effects were reported. Drug Dev. Res. 59:292–306, 2003. © 2003 Wiley‐Liss, Inc. 相似文献
8.
Antagonism of arachidonic acid is linked to the antitumorigenic effect of dietary eicosapentaenoic acid in Apc(Min/+) mice 总被引:1,自引:0,他引:1
The multiple intestinal neoplasia (Apc(Min/+)) mouse possesses a germline mutation at codon 850 of the adenomatous polyposis coli (Apc) gene resulting in the formation of a nonfunctional truncated gene product. Following a somatic mutation of the remaining wild-type allele, mice spontaneously develop approximately 40-50 tumors throughout the intestinal tract. This mouse model has been used to study intestinal tumorigenesis because this mutation is analogous to the inherited APC mutation in humans with familial adenomatous polyposis (FAP). These individuals characteristically develop numerous adenomas throughout their intestinal tracts. Only a few studies have evaluated the effects of dietary fatty acids on tumorigenesis in this animal model with varying results, and none have linked these effects to alterations in arachidonic acid (AA) metabolism. This study was designed to evaluate the antitumorigenic effect of dietary (n-3) polyunsaturated fatty acids (PUFA) in the Apc(Min/+) mouse model and to determine whether these effects are related to inhibition of AA metabolism. Male Apc(Min/+)mice were fed diets supplemented with eicosapentaenoic acid (EPA), AA or a combination of AA + EPA. Mean tumor number in the EPA group was 68% lower (P<0.05) compared with the control group, whereas AA supplementation did not significantly alter tumor load. The reduction in tumor load coincided with significant reductions in intestinal AA content and levels of prostaglandins. However, supplementing AA to the EPA diet (AA + EPA) abolished the antitumorigenic effect of EPA, increased tissue AA content fourfold and prostaglandin production two- to fourfold. These results indicate that AA is involved in tumorigenesis and suggest that EPA's ability to reduce tumor load in Apc(Min/+) mice is related to reductions in tissue AA content or its metabolism. 相似文献
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