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1.
MUAMMER SEYHAN BAAK KANDI COKUN HÜLYA SALAM HAMDI ÖZCAN YELDA KARINCAOLU 《Pediatrics international》2006,48(6):525-530
BACKGROUND: The present study was aimed to define the gender ratio, familial occurrence, age of onset, precipitating factors, clinical types, nail and joint involvement of psoriasis in childhood and adolescence in Turkey. METHODS: A total of 61 children with psoriasis under 18 years old were evaluated retrospectively, for age, gender, age of disease onset, family history, concomitant disease, the clinical type of psoriasis, clinical localization, nail and joint involvement and treatment modalities. RESULTS: Of the patients, 23 (37.70%) were boys and 38 (62.30%) were girls. Mean age was 9.28 +/- 4.02 years in girls and 11.18 +/- 3.85 years in boys (9.96 +/- 4.03 years in all children). Mean age at the onset of the disease was 6.81 +/- 4.11 years in girls and 7.03 +/- 4.28 years in boys (6.89 +/- 4.14 years in all patients). In 14 (23%) cases, a positive family history was detected. The most frequent probable triggering factors were upper respiratory tract infections (14.8%) and positive throat culture for A group ss-hemolytic streptococcus (21.3%). Frequency of emotional stress and psychiatric morbidity were 54% and 9.8%, respectively. The most frequent localizations at onset were trunk (44.3%), extremities (54.0%), and scalp (36.0%). Three children (4.9%) had a history of dissemination from psoriatic diaper rash. In total, 51 (83.6%) patients presented with psoriasis vulgaris, eight (13.1%) with generalized pustular psoriasis, and the remaining two (3.3%) with erythrodermic psoriasis. CONCLUSION: The incidence of psoriasis among dermatological patients in childhood and adolescence was 3.8%. The disease tends to appear earlier in girls than boys. The authors suggested that stress and upper respiratory infections are the most important triggering factors in childhood and adolescence psoriasis. 相似文献
2.
V Aerra M Kuduvalli AN Moloto AK Srinivasan AD Grayson BM Fabri AY Oo 《Journal of cardiothoracic surgery》2006,1(1):6-5
Background
Atrial fibrillation can occur in up to 40% of patients undergoing coronary surgery. 相似文献3.
Dipankar Nandi Helen Smith Sarah Owen Carole Joint John Stein Tipu Aziz 《Journal of clinical neuroscience》2002,9(5):557-561
Central post stroke pain is often difficult to manage satisfactorily with conventional treatment modalities for pain. In the last decade functional neurosurgery has offered hope with motor cortex stimulation achieving significant alleviation of pain in some patients. Unfortunately this has led to the neglect of chronic stimulation of deep grey matter as another modality of treating this condition. In this article we present our experience with motor cortex stimulation and that with deep grey matter stimulation in patients with post stroke pain. We argue that both modalities have a significant role and that what is required are better methods of identifying particular patients who are more likely to respond to one or the other. 相似文献
4.
Sumon Nandi Steven Maschke Peter J. Evans Jeffrey N. Lawton 《Hand (New York, N.Y.)》2009,4(4):368-379
Elbow motion is essential for upper extremity function to position the hand in space. Unfortunately, the elbow joint is prone
to stiffness following a multitude of traumatic and atraumatic etiologies. Elbow stiffness can be diagnosed with a complete
history and physical exam, supplemented with appropriate imaging studies. The stiff elbow is challenging to treat, and thus,
its prevention is of paramount importance. When this approach fails, non-operative followed by operative treatment modalities
should be pursued. Upon initial presentation in those who have minimal contractures of 6-month duration or less, static and
dynamic splinting, serial casting, continuous passive motion, occupational/physical therapy, and manipulation are non-operative
treatment modalities that may be attempted. A stiff elbow that is refractory to non-operative management can be treated surgically,
either arthroscopically or open, to eliminate soft tissue or bony blocks to motion. In the future, efforts to prevent and
treat elbow stiffness may target the basic science mechanisms involved. Our purpose was to review the etiologies, classification,
evaluation, prevention, operative, and non-operative treatment of the stiff elbow. 相似文献
5.
P. K. Nandi 《Archives of virology》1998,143(7):1251-1263
Summary. The human prion peptide PrP106–126 polymerizes in the presence of DNA both in its circular and linearized forms under solution
conditions where the peptide alone does not polymerize. The polymerization process has been monitored by the increase in the
fluorescence of anilino naphthalene sulfonic dye which detects the availability of the hydrophobic surface(s) in the aggregate
as a consequence of polymerization. The polymerization is a nucleation dependent phenomenon as is evidenced from an existence
of a lag period before the onset of the polymerization and a strong dependence of the polymerization on the prion peptide
concentrations. The reaction is dependent on the pH as seen from rapid polymerization at pH 5 compared to the reaction at
neutral pH where no polymerization is observed after a relatively long period of incubation. The polymer has been characterized
as amyloid by using new absorbing and emitting species resulting from the interaction of the polymer with the amyloid specific
fluorescent dye, Thioflavine S. This is probably the first demonstration that an endogenous macromolecule can influence the
polymerization of a prion peptide. We have previously shown that there is a conformational change in the nucleic acid as a
consequence of this interaction. This prion peptide is considered as a model to understand prion diseases as is evidenced
from its toxicity towards primary brain cells in culture. The peptide encompasses one of the important amyloidogenic regions
of the normal cellular prion protein. Demonstration of nucleic acid induced polymerization of the normal and scrapie prion
isoforms accompanying a change in the nucleic acid conformation can establish a possible role of nucleic acid in prion disease.
Received January 8, 1997 Accepted March 4, 1998 相似文献
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O6-Alkylguanine--DNA alkyltransferase (AGT) is a protein which removes the promutagenic O6-alkylguanine lesion induced in DNA by alkylating agents. Our results demonstrate that freshly isolated organoids from reduction mammoplasty specimens contain significant levels of AGT activity. AGT activity in breast epithelial cells shows interindividual variation. Constitutive levels of AGT activity remain unchanged during short-term serum-free culture of breast epithelial cells inside three-dimensional rat-tail collagen gel matrix. In the present study, we optimized conditions for depleting AGT activity in human breast epithelial cells cultured in three-dimensional collagen gel matrix using O6-methylguanine and O6-benzylguanine which are substrates for AGT. AGT activity was efficiently inactivated by exposure of cells to O6-methylguanine or O6-benzylguanine. Inactivation with O6-benzylguanine was more rapid, of greater magnitude and consistency and occurred at lower concentrations than with O6-methylguanine. Near-complete inactivation (> 99.5%) of AGT activity was reproducibly achieved with 50 microM O6-benzylguanine. In contrast, 500 microM O6-methylguanine was needed to obtain a maximal effect and this reduced AGT activity by only 53-93% of control. Within 30 min of adding the free base, 50 microM O6-benzylguanine depleted 95% of the levels of AGT compared to 30% inhibition with 500 microM O6-methylguanine. The profile for restoration of AGT activity was different following a 24 h incubation and subsequent removal of each of the guanine derivatives. AGT activity levels remained undetectable for at least 2 days after removal of 50 microM O6-benzylguanine from the medium and recovered to only 53% of control values after an additional 3 days. AGT activity levels remained undetectable for at least 2 days after removal of 50 microM O6-benzylguanine from the medium and recovered to only 53% of control values after an additional 3 days. In contrast, following removal of 500 microM O6-methylguanine, the activity was restored from its nadir of 16% of control values reaching pretreatment levels after 5 days. These results suggest that treatment with O6-benzylguanine may be used to modulate the incidence of transforming mutations in cultured human breast epithelial cells treated with chemical carcinogens which give rise to O6-alkylguanine adducts. 相似文献
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