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1.
Previous studies indicate that crude oil leads to increased pigmentation and erythema (sunburn) in response to sunlight in exposed individuals. However, no information is currently available concerning whether crude oil exposure might enhance the immunosuppressive effects of solar ultraviolet radiation (UVR) on the skin. In order to address this question, the back skin of shaved, female C3H/HeN mice was exposed to crude oil with or without subsequent treatment with medium-wavelength (UVB) (200 J/m2) or long-wavelength (UVA) (20,000 J/m2) UVR. Immune function was assessed in treated mice by measuring their ability to mount contact hypersensitivity responses to a hapten (2,4-dinitro-1-flyorobenzene, DNGFB) applied to the site of crude oil and UVR treatment as determined by ear swelling upon subsequent challenge. Since Langerhans cells represent an important component of immunity within the skin and because suppression of contact hypersensitivity following UVR treatment is often accompanied by disappearance of Langerhans cells from the epidermis, the impact of these agents on epidermal Langerhans cell density was also analyzed. This was accomplished by enumerating IA-positive cells within the epidermis of treated skin. In these studies, crude oil alone induced inhibition of contact hypersensitivity but had no effect on epidermal Langerhans cells. In contrast, combined treatment with crude oil and UVA led to suppression of contact hypersensitivity, which was accompanied by depletion of epidermal Langerhans cells. 相似文献
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F Moulin B Ameline Y Redor A Bey Boumerzag J Haut 《Journal fran?ais d'ophtalmologie》1992,15(8-9):463-468
To appreciate the current place of argon laser trabeculoplasty (ALT) in the therapeutic armamentarium of primary open-angle glaucoma (POAG), the first 211 photocoagulated phakic eyes were analysed. One hundred and fifty-nine eyes had a 5 year-follow-up and 147 eyes had a minimal 8 year-follow-up. These eyes came from an initial group of 151 patients: 76 women and 75 men with a mean age of 66 years. We decided, arbitrarily, to assess trabeculoplasty results according to three combined criteria of failure (insufficient or transient intraocular pressure drop (3 mmHg), progression in visual field loss and need for a filtrating surgery) and to various expected goals: prevent an increase of drugs with their subsequent side effects, taper a non tolerated medical treatment and, lastly, try to cease all medical treatment in non compliant patients. According to these criteria, during the first five years, the cumulative failure rate in the 159 eyes rose steadily from 19% (31 eyes) in the first year to 52% (82 eyes) in the fifth year. The initial mean intraocular pressure (27.22 mmHg) of 7 failures operated on during the first 2 months and that of all 27 operated on failures (24.41 mmHg) was higher than the initial mean intraocular pressure of the 77 successful cases (22.67 mmHg). In the 77 eyes still controlled at 5 years, the intraocular pressure drop was 6.57 mmHg.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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U Tirelli V Zagonel D Serraino J Thomas B Hoerni A Tangury U Ruhl P Bey N Tubiana W P Breed 《Journal of clinical oncology》1988,6(11):1708-1713
The results of a European Organization for Research and Treatment of Cancer (EORTC) retrospective study on non-Hodgkin's lymphoma (NHL) in elderly patients (greater than or equal to 70 years of age) seen in Europe in 1984 are reported. A precodified form was sent to 55 European institutes in order to evaluate the incidence of NHL in the elderly with regard to natural history, treatment-related toxicity, response, and survival. Thirteen institutes participated in the study. One hundred thirty-seven cases of NHL were observed in the elderly during 1984, making up 28% of the total number of NHL seen in those institutes. The median age was 77 years; 21% of the patients had favorable (low-grade) and 73% unfavorable (intermediate- and high-grade) histology, according to the Working Formulation. Stage at presentation was localized (I and II) in 60% and advanced in 37% of the patients. Most of the physicians used standard therapy regimens at reduced doses, from the beginning of the treatment. Sixty patients (44%) underwent a "conservative" treatment (one or two antineoplastic drugs or local field radiotherapy) and 77 (56%) an "aggressive" treatment (polychemotherapy regimens or extended field radiotherapy). Response was similar between the two treatment groups, but severe and lethal toxicity was significantly higher among patients treated with aggressive therapy. Prospective randomized studies are clearly needed to define the optimal treatment in elderly patients with advanced unfavorable NHL. 相似文献
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Dohle GR; Ramos L; Pieters MH; Braat DD; Weber RF 《Human reproduction (Oxford, England)》1998,13(3):620-623
Male genital tract obstructions may result from infections, previous
inguinal and scrotal surgery (vasectomy) and congenital bilateral absence
of the vas deferens (CBAVD). Microsurgery can sometimes be successful in
treating the obstruction. In other cases and in cases of failed surgical
intervention, the patient can be treated by microsurgical or percutaneous
epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction
(TESE) and intracytoplasmic sperm injection (ICSI). We present the results
of 39 ICSI procedures for obstructive azoospermia in 24 couples. The
aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD
in nine and genital infections in four. Sperm retrieval was accomplished
via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was
only applied when PESA failed to produce enough spermatozoa for
simultaneous ICSI. In six patients, the ICSI procedure was performed with
cryopreserved spermatozoa after an initial PESA procedure. Fertilization
occurred in 47% of the metaphase II oocytes; embryo transfer was performed
in 92% of procedures and resulted in a clinical pregnancy in 13/39
procedures. Ongoing pregnancy was achieved in 10/39 procedures. One
pregnancy was terminated early after prenatal investigation showed a
cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine
pregnancies resulted in the live birth of 10 children, without any
congenital abnormalities. Epididymal and testicular retrieved spermatozoa
were successfully used for ICSI to treat obstructive azoospermia, and
resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI
procedures, a success rate of 25.6% per treatment cycle and of 27.7% per
embryo transfer.
相似文献
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L1 knockout mice show dilated ventricles, vermis hypoplasia and impaired exploration patterns 总被引:8,自引:3,他引:8
Fransen E; D'Hooge R; Van Camp G; Verhoye M; Sijbers J; Reyniers E; Soriano P; Kamiguchi H; Willemsen R; Koekkoek SK; De Zeeuw CI; De Deyn PP; Van der Linden A; Lemmon V; Kooy RF; Willems PJ 《Human molecular genetics》1998,7(6):999-1009
L1 is a neural cell adhesion molecule mainly involved in axon guidance and
neuronal migration during brain development. Mutations in the human L1 gene
give rise to a complex clinical picture, with mental retardation,
neurologic abnormalities and a variable degree of hydrocephalus. Recently,
a transgenic mouse model with a targeted null mutation in the L1 gene was
generated. These knockout (KO) mice show hypoplasia of the corticospinal
tract. Here we have performed further studies of these KO mice including
magnetic resonance imaging of the brain, neuropathological analysis and
behavioral testing. The ventricular system was shown to be abnormal with
dilatation of the lateral ventricles and the 4th ventricle, and an altered
shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the
KO mice is hypoplastic. Their exploratory behavior is characterized by
stereotype peripheral circling reminiscent of that of rodents with induced
cerebellar lesions.
相似文献
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目的: 研究1,25-二羟维生素D3 对结肠癌细胞系Caco-2 细胞中报告基因表达的作用,并探讨在报告载体pGL2 序列中存在潜在的抑制性维生素D应答元件(VDRE)的可能性。方法: 采用磷酸钙沉淀法将报告载体转染入Caco-2 细胞。Caco-2细胞经不同浓度1,25-二羟维生素D3 处理后测定细胞裂解液中表达的荧光素酶活性。结果: 应用pGL2 报告载体时,当用pSG5-VDR表达载体共转染后,1,25-二羟维生素D3显著地抑制Caco-2 细胞荧光素酶的表达(P< 0.05);而未使用该表达载体共转染则无抑制作用(P> 0.05)。应用pGL3 报告载体时,不同浓度的1,25-二羟维生素D3 对pLG3转染后Caco-2 细胞表达的荧光素酶活性均无显著抑制作用(P> 0.05),该作用不依赖是否存在有pSG5-VDR表达载体共转染。结论:1,25-二羟维生素D3 对报告载体PGL2 荧光素酶表达具有抑制作用,而对pGL3 则否;类似人类PTH基因中的潜在抑制性VDRE存在于报告载体pGL2,在pGL3 中该VDRE业已改变。 相似文献