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101.
Anna B?ogowska Izabella Rzepka-Górska S?awomir Zó?towski 《Gynecological endocrinology》2005,20(5):270-273
OBJECTIVE: Constitutional delay of puberty (CDP) is the absence of secondary sexual features in otherwise healthy girls past the 13th year of life. The aim of the present work was to follow the development of estrogen-dependent sexual features, determine the concentrations of gonadotropins, estradiol and sex hormone-binding globulin (SHBG) in girls with CDP at menarche and compare the findings with normal controls. METHODS: We enrolled 11 girls with CDP and 40 controls. Primary, secondary and tertiary sexual features were studied at menarche +/- 3 months. The size of the ovaries and uterus was measured using transabdominal ultrasound. Maturation of breasts and pubic hair was staged according to Tanner. Concentrations of gonadotropins (follicle-stimulating hormone (FSH), luteinizing hormone) and estradiol were measured with immunoenzymatic methods. For measurement of SHBG, a radioimmunoassay was applied. RESULTS: Menarche in CDP girls usually appeared with Stage IV or V of breast development and Stage IV of pubic hair development according to Tanner. CDP girls demonstrated a significantly smaller volume of the uterine body at menarche compared with controls (p = 0.0004). Significantly lower levels of FSH (p = 0.0363) and estradiol (p = 0.0332), as well as a tendency towards lower levels of SHBG, were revealed in CDP girls at menarche. CONCLUSION: In CDP girls, menarche is accompanied by more mature tertiary sexual features, apparently resulting from longer exposure of estrogen-dependent tissues to the action of bioactive endogenous estrogens. The smaller volume of the uterine body in CDP girls at menarche may be attributed to decreased concentrations of FSH and estradiol, as well as to the possibility of decreased insulin-like growth factor-1 and increased neuropeptide Y levels. 相似文献
102.
Contractile and endothelium-dependent dilatory responses of cerebral arteries at various extracellular magnesium concentrations 总被引:3,自引:0,他引:3
M Faragó C Szabó E Dóra I Horváth A G Kovách 《Journal of cerebral blood flow and metabolism》1991,11(1):161-164
To clarify the effect of extracellular magnesium (Mg2+) on the vascular reactivity of feline isolated middle cerebral arteries, the effects of slight alterations in the Mg2+ concentration on the contractile and endothelium-dependent dilatory responses were investigated in vitro. The contractions, induced by 10(-8)-10(-5) M norepinephrine, were significantly potentiated at low Mg2+ (0.8 mM v. the normal, 1.2 mM). High (1.6 and 2.0 mM) Mg2+ exhibited an inhibitory effect on the contractile responses. No significant changes, however, in the EC50 values for norepinephrine were found. The endothelium-dependent relaxations induced by 10(-8)-10(-5) M acetylcholine were inhibited by high (1.6 and 2.0 mM) Mg2+. Lowering of the Mg2+ concentration to 0.8 mM or total withdrawal of this ion from the medium failed to alter the dilatory potency of acetylcholine. The changes in the dilatory responses also shifted the EC50 values for acetylcholine to the right. The present results show that the contractile responses of the cerebral arteries are extremely susceptible to the changes of Mg2+ concentrations. In response to contractile and endothelium-dependent dilatory agonists, Mg2+ probably affects both the calcium influx into the endothelial and smooth muscle cells as well as the binding of acetylcholine to its endothelial receptor. Since Mg2+ deficiency might facilitate the contractile but not the endothelium-dependent relaxant responses, the present study supports a role for Mg2+ deficiency in the development of the cerebral vasospasm. 相似文献
103.
G Rózsa 《Orvosi hetilap》1989,130(44):2377-2378
104.
António Travassos Susana Teixeira Pinto Ferreira Isaura Regadas Ana Sofia Travassos Florindo Esteves Esperancinha Isabel Prieto Grapa Pires Robert van Velze A Valido Maria do Céu Machado 《Ophthalmic surgery, lasers & imaging》2007,38(3):233-237
The anatomic response to intravitreal bevacizumab injection in three patients with aggressive, posterior retinopathy of prematurity is described. In all cases, the worse eye was treated with a single intravitreal injection of 0.75 mg of bevacizumab as monotherapy or complementary to laser therapy. In 24 hours, all injected eyes showed regression of the tunica vasculosa lentis and iris vessel engorgement and disappearance of iris rigidity. In addition, plus disease and retinal proliferation began to regress. None of the eyes required additional treatment. Follow-up of up to 10 months 相似文献
105.
A 47-year-old man, was referred for evaluation of asymptomatic splenomegaly in September 1981, and a diagnosis of hairy cell leukemia (HCL) at the initial clinical stage was made. The patient remained asymptomatic until May 1985, when splenectomy was performed because of anemia and splenomegaly. Bone marrow and liver biopsy specimens showed diffuse infiltration by abnormal tartase resistant acid phosphatase (TRAP) positive lymphocytes with typical aspect of hairy cells. Four months later, he developed fever of unknown origin and, at laparotomy, diffuse retroperitoneal lymph node enlargement and metastatic liver nodules were seen. Lymph node and liver biopsy specimens showed diffuse infiltration by abnormal large lymphocytes, which bore monoclonal surface immunoglobulin M and light chain kappa. Only six cases of non-Hodgkin's lymphoma associated with HCL have been published to date. This report describes an additional case of immunoblastic B-cell lymphoma, preceded 4 years earlier by the diagnosis of HCL. 相似文献
106.
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110.
The smoking control policies recommended by the World Health Organisation have achieved a slight decrease in smoking prevalence in developed countries, although associated mortality is still very high. The use of tobacco products other than cigarettes and even medicinal nicotine (known as nicotine replacement therapy [NRT]) has been proposed as a risk reduction strategy. Among the tobacco products with less individual risk than cigarettes would be any type of tobacco without smoke (smokeless) with a low content in nitrosamines and modified cigarettes; both forms included under the PREP (Potentially Reduced Exposure Products) concept. The idea would be to promote these products among patients who cannot quit smoking or wish to reduce their risk without giving up nicotine intake. The possible effects of risk reduction strategies, including PREP, on the decreased prevalence and morbidity and mortality are reviewed, and the possible implications that this measure could have in Spain are analysed. Tobacco control measures in Spain have only been made recently and are still insufficient. Therefore, the current priority in Spain is to develop control policies that have proven to be more than effective. The marketing and advertising of new tobacco products, even with reduced potential risk, seems more a serious threat than an opportunity for developing smoking control policies. 相似文献