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391.
CJM Lips EGWM Lentjes JWM Höppener RB van der Luijt FL Moll 《Hereditary cancer in clinical practice》2006,4(4):169-176
Paragangliomas are rare tumours of the autonomic nervous system and occur in sporadic and hereditary forms. They are usually benign and have a low mortality. However, they cause significant morbidity related to their mass effect. Genetic predisposition can occur within the familial tumour syndromes multiple endocrine neoplasia type 2 (MEN 2), von Hippel-Lindau (VHL) and neurofibromatosis type 1 (NF-1), or be due to mutations in genes specific to the development of paraganglioma only. Compared to sporadic forms, familial paragangliomas tend to present at a younger age and at multiple sites. Tumours should be diagnosed and resected as early as possible, as it has been shown that morbidity is related to tumour size. This article gives an overview of the current literature on the origin of the different forms of paragangliomas, DNA diagnosis, as well as biochemical and radiological screening guidelines. 相似文献
392.
393.
394.
Katherine S Ruth Purdey J Campbell Shelby Chew Ee Mun Lim Narelle Hadlow Bronwyn GA Stuckey Suzanne J Brown Bjarke Feenstra John Joseph Gabriela L Surdulescu Hou Feng Zheng J Brent Richards Anna Murray Tim D Spector Scott G Wilson John RB Perry 《European journal of human genetics : EJHG》2016,24(2):284-290
Genetic factors contribute strongly to sex hormone levels, yet knowledge of the regulatory mechanisms remains incomplete. Genome-wide association studies (GWAS) have identified only a small number of loci associated with sex hormone levels, with several reproductive hormones yet to be assessed. The aim of the study was to identify novel genetic variants contributing to the regulation of sex hormones. We performed GWAS using genotypes imputed from the 1000 Genomes reference panel. The study used genotype and phenotype data from a UK twin register. We included 2913 individuals (up to 294 males) from the Twins UK study, excluding individuals receiving hormone treatment. Phenotypes were standardised for age, sex, BMI, stage of menstrual cycle and menopausal status. We tested 7 879 351 autosomal SNPs for association with levels of dehydroepiandrosterone sulphate (DHEAS), oestradiol, free androgen index (FAI), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, progesterone, sex hormone-binding globulin and testosterone. Eight independent genetic variants reached genome-wide significance (P<5 × 10−8), with minor allele frequencies of 1.3–23.9%. Novel signals included variants for progesterone (P=7.68 × 10−12), oestradiol (P=1.63 × 10−8) and FAI (P=1.50 × 10−8). A genetic variant near the FSHB gene was identified which influenced both FSH (P=1.74 × 10−8) and LH (P=3.94 × 10−9) levels. A separate locus on chromosome 7 was associated with both DHEAS (P=1.82 × 10−14) and progesterone (P=6.09 × 10−14). This study highlights loci that are relevant to reproductive function and suggests overlap in the genetic basis of hormone regulation. 相似文献
395.
CRM Lammens EMA Bleiker S Verhoef FJ Hes MGEM Ausems D Majoor‐Krakauer RH Sijmons RB Van Der Luijt AMW Van Den Ouweland Tam Van Os N Hoogerbrugge EB Gómez García CJ Dommering CM Gundy NK Aaronson 《Clinical genetics》2010,77(5):483-491
Lammens CRM, Bleiker EMA, Verhoef S, Hes FJ, Ausems MGEM, Majoor‐Krakauer D, Sijmons RH, Luijt van der RB, Ouweland van den AMW, Van Os Tam, Hoogerbrugge N, Gomez‐Garcia EB, Dommering CJ, Gundy CM, Aaronson NK. Psychosocial impact of von Hippel–Lindau disease: levels and sources of distress. Von Hippel–Lindau disease (VHL) is a hereditary tumor susceptibility syndrome, characterized by an increased risk of developing multiple benign and malignant tumors at various sites and ages with limited preventive options. This study evaluates the prevalence of distress among VHL family members and factors associated significantly with such distress. Forty‐eight families with a VHL mutation were identified via the nine family cancer clinics in the Netherlands. In total, 171 family members (carriers, 50% at‐risk, non‐carriers) were approached, of whom 123 (72%) completed a self‐report questionnaire. Approximately 40% of the VHL family members reported clinically relevant levels of distress, approaching 50% among the carriers and, possibly even more striking, 36% among the non‐carriers. Having lost a first degree relative due to VHL during adolescence (OR 11.2; 95% CI 1.4–86.9) was related significantly to heightened levels of distress. Approximately, only one‐third of those who reported heightened levels of distress had received professional psychosocial support. A substantial percentage of family members experience clinically relevant levels of distress. We would recommend the introduction of a procedure for screening for distress in this vulnerable population. Special attention should be paid to those individuals who have lost a close relative due to VHL during adolescence. 相似文献
396.
C Evans N Peter M Gibson EPH Torrie RB Galland TR Magee 《Annals of the Royal College of Surgeons of England》2010,92(4):347-352
INTRODUCTION
Retrograde transpopliteal angioplasty (PA) is a potentially useful alternative technique for endovascular treatment of infra-inguinal arterial disease when antegrade transfemoral puncture (FA) is technically not possible or appropriate. This study aimed to investigate the outcomes of PA compared with FA during a 5-year period.PATIENTS AND METHODS
A retrospective study was performed to assess 88 PA and 275 FA performed between January 2003 and January 2008. Assessments of patients, indication for procedure, disease site, stenosis severity, procedure outcomes and time to further intervention were recorded.RESULTS
FA was used to treat more patients with critical ischaemia (42.2% vs 30.7%; P = 0.014)). PA was used to treat more proximal superficial femoral lesions (P < 0.001) and occlusive lesions (P = 0.001). Overall, 84.1% of PA and 82.5 % of FA were technically successful. There was no difference in local puncture site complication rates. Significantly more FA resulted in distal thrombus/embolism (8.4% vs 3.4%; P = 0.044). Further intervention was required in 27.3% of PA and 36.0% of FA. The time interval to re-intervention was not different between the groups.CONCLUSIONS
PA is safe with comparable success rates and long-term outcomes to an FA. PA is a useful alternative approach or treating occlusive, proximal disease. 相似文献397.
Wesely Edward Gnanaraj Johnson Marimuthu Antonisamy Mohanamathi RB Kavitha Marappampalyam Subramanian 《Asian Pacific Journal of Tropical Biomedicine》2012,2(1):1-5
Objective
To develop the reproducible in vitro propagation protocols for the medicinally important plants viz., Achyranthes aspera (A. aspera) L. and Achyranthes bidentata (A. bidentata) Blume using nodal segments as explants.Methods
Young shoots of A. aspera and A. bidentata were harvested and washed with running tap water and treated with 0.1% bavistin and rinsed twice with distilled water. Then the explants were surface sterilized with 0.1% (w/v) HgCl2 solutions for 1 min. After rinsing with sterile distilled water for 3–4 times, nodal segments were cut into smaller segments (1 cm) and used as the explants. The explants were placed horizontally as well as vertically on solid basal Murashige and Skoog (MS) medium supplemented with 3% sucrose, 0.6% (w/v) agar (Hi-Media, Mumbai) and different concentration and combination of 6-benzyl amino purine (BAP), kinetin (Kin), naphthalene acetic acid (NAA) and indole acetic acid (IAA) for direct regeneration.Results
Adventitious proliferation was obtained from A. aspera and A. bidentata nodal segments inoculated on MS basal medium with 3% sucrose and augmented with BAP and Kin with varied frequency. MS medium augmented with 3.0 mg/L of BAP showed the highest percentage (93.60±0.71) of shootlets formation for A. aspera and (94.70±0.53) percentages for A. bidentata. Maximum number of shoots/explants (10.60±0.36) for A. aspera and (9.50±0.56) for A. bidentata was observed in MS medium fortified with 5.0 mg/L of BAP. For A. aspera, maximum mean length (5.50±0.34) of shootlets was obtained in MS medium augmented with 3.0 mg/L of Kin and for A. bidentata (5.40±0.61) was observed in the very same concentration. The highest percentage, maximum number of rootlets/shootlet and mean length of rootlets were observed in 1/2 MS medium supplemented with 1.0 mg/L of IBA. Seventy percentages of plants were successfully established in polycups. Sixty eight percentages of plants were well established in the green house condition. Sixty five percentages of plants were established in the field.Conclusions
The results have shown that use of nodal buds is an alternative reproducible and dependable method for clonal propagation of A. aspera and A. bidentata. The high rate of direct shoot-root multiplication and their high rate of post-hardening survival indicate that this protocol can be easily adopted for commercial large scale cultivation. 相似文献398.
Lt Col Sourav Sen Sunil Sanghi ) Col K Shanmuganandan )RM Gupta ) Brig Ketoki Kapila AK Praharaj Col Satish Kumar RB Batra 《Medical Journal Armed Forces India》2011,67(1):15-20
Background: Studies in human immunodeficiency virus (HIV) infected adults have demonstrated association of total lymphocyte count (TLC) <1200/mm3 and subseqnent disease progression or mortality. The association of other surrogate makers such as haemoglobin (Hb), and erythrocyte sedimentation rate (ESR) with CD4 count and disease progression has also been suggested. This study was carried out to determine the relationship of CD4-positive T lymphocyte counts with TLC, Hb and ESR in HIV-infected individuals.Methods: The study population comprised of 215 antiretroviral treatment naive HIV-1 infected adults. The CD4 positive T cell counts, TLC, Hb and ESR of study participants were measured. Spearman's rank order correlation and Receiver Operating Characteristic were used for statistical analyses.Result: The sensitivity, specificity, positive and negative likelihood ratios for cut-off value of TLC <1200/mm3 for predicting CD4 counts <200 cells/mm3 and <350 cells/mm3 were 9.4%, 100%, not measurable and 1.1, and 6.1 %, 98.8 %, 5.13 and 0.95, respectively. The association of Hb (<10, 11, 12 g/dl and <10, 12, 14 g/dl for CD4 counts <200 cells/mm3 and <350 cells/mm3, respectively), and ESR (<10, 20 and 30 mm fall after 1 hour) with these two CD4 counts cut-off values were suboptimal.Conclusion: This study reveals the poor association of TLC, Hb, and ESR with CD4 counts in HIV infected adults, thus highlighting the need to review the utility of these surrogate markers, for predicting CD4 counts in people living with HIV/AIDS. 相似文献
399.
Corpus callosum and subcallosal-periventricular lesions in multiple sclerosis: detection with MR 总被引:1,自引:0,他引:1
Simon JH; Holtas SL; Schiffer RB; Rudick RA; Herndon RM; Kido DK; Utz R 《Radiology》1986,160(2):363-367
Examination with magnetic resonance imaging of 40 patients with confirmed diagnoses of multiple sclerosis showed that corpus callosum involvement is common. Thirty percent of the patients had focal callosal lesions similar to those described in the pathology literature. Long, inner callosal-subcallosal lesions were found in 55% of patients. These lesions had signal characteristics similar to those of noncallosal periventricular lesions. Diffuse moderate to severe atrophy of the corpus callosum was noted in 40% of patients, with one exception concurrent with inner callosal lesions. The nature of the inner callosal lesions is not known, since these lesions are not typically described in the literature. These lesions may represent demyelination or increased water content and may be the precursor to atrophy that progresses from the ependymal surface toward the outer fibers of the corpus callosum. 相似文献
400.
A pilot study of the human chorionic gonadotrophin test for ovarian hyperandrogenism 总被引:1,自引:4,他引:1
A controlled clinical study was designed to investigate the value of human
chorionic gonadotrophin (HCG) challenge as a test for functional ovarian
hyperandrogenism. Dexamethasone administration was followed by 5000 IU HCG
and blood samples for steroid hormone assay were obtained 0, 8, 16, and 24
h thereafter. Study subjects were normal women (n = 13); women with
functional ovarian hyperandrogenism, defined by androgen excess,
amenorrhoea and an increased 17-hydroxyprogesterone response to nafarelin
(n = 6); and normal men (n = 4). The responses of 17-hydroxyprogesterone,
androstenedione and testosterone to HCG in women with functional ovarian
hyperandrogenism were significantly greater than in normal women. However,
the 17-hydroxyprogesterone response to HCG in functional ovarian
hyperandrogenism was significantly lower after HCG than after nafarelin.
The oestradiol response was also significantly lower after HCG than
nafarelin, although oestradiol concentration more than doubled in normal
women as well as in women with functional ovarian hyperandrogenism. The
responses to HCG confirm that functional ovarian hyperandrogenism
abnormalities are luteinizing hormone (LH)-dependent. Therefore, the 17-
hydroxyprogesterone response to HCG could represent a useful test for the
diagnosis of ovarian hyperandrogenism. The lower 17- hydroxyprogesterone
response to HCG than to nafarelin in functional ovarian hyperandrogenism
suggests that a follicle-stimulating hormone (FSH)-responsive factor
modulates thecal 17-hydroxyprogesterone secretion. The oestradiol response
to HCG is consistent with HCG directly stimulating the oestradiol secretion
by thecal cells.
相似文献