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91.
Translocation breakpoints are clustered on both chromosome 8 and chromosome 21 in the t(8;21) of acute myeloid leukemia 总被引:3,自引:0,他引:3
The t(8;21)(q22;q22) is consistently associated with acute myeloid leukemia (AML) M2. Recent data have suggested that breakpoints on chromosome 21 are clustered within a single intron of a novel gene, AML1, just downstream of a region of homology to the runt gene of D melanogaster. In this report, we confirm rearrangement at the same location in at least 12 of 18 patients with t(8;21). Furthermore, we have isolated recombinant clones spanning the breakpoint regions on both the der(8) and the der(21) from one patient. By using a chromosome 8 probe derived from these clones, we show that t(8;21) breakpoints are also clustered on chromosome 8. 相似文献
92.
Corlien JH de Vries Margreet Wieringa-de Waard Patrick JE Bindels Willem M Ankum 《The British journal of general practice》2011,61(587):e340-e346
Background
Diagnostic ultrasonography is used by GPs in approximately 10% of patients of reproductive age with abnormal vaginal bleeding. Transvaginal sonography is recommended as a first-line diagnostic instrument for assessing uterine pathology.Aim
To assess if findings resulting from openaccess sonography were in agreement with the GPs’ working hypotheses and if these findings contributed to GPs’ management.Design and setting
Prospective observational cohort study of GPs working in the health district of the Academic Medical Center, Amsterdam and their patients consulting with abnormal vaginal bleeding.Method
Data on patients’ history, GPs’ primary working hypotheses, and intended management were recorded. After sonography, GPs recorded their actual management.Results
A total of 122 patients were included by 18 GPs from June 2003 to December 2004. Data from 89 patients were available for analysis. The GPs’ working hypotheses implied ‘no structural pathology’ in 65/89 patients, and ‘fibroids’ in 24/89 patients. Sonographic findings were confirmed in 50/65 patients where ‘no structural pathology’, and in 14/24 of those where ‘fibroids’ were expected. Initially, GPs had intended to refer nine patients to a gynaecologist. Actual management after sonographic assessment was watchful waiting or drug therapy in 57/89 patients. Eighty-nine per cent of these patients had normal sonographic findings. The actual referral rate rose to 27/89 patients. In 17 referred patients, sonographic findings were suggestive of intracavitary abnormalities.Conclusion
Open-access sonography contributed to more accurate diagnoses and improved GPs’ management of women with abnormal vaginal bleeding. 相似文献93.
Background
In November 2006, an email-based health promotion program for pregnant women was implemented nationally in the Netherlands. The program consisted of emails containing quizzes with pregnancy-related questions tailored to the number of weeks of pregnancy. Emails were sent out once every 4 weeks, up to a maximum of nine emails.Objectives
The aims of the study were (1) to assess the recruitment of participants and their representativeness of the Dutch population and (2) to study differences in recruitment, program use, and program appreciation among women with different levels of education.Methods
Data from 13,946 pregnant women who enrolled during the first year of the program were included. Upon registration, participants were asked how they found out about the program and subsequently received an email questionnaire to assess demographic, lifestyle, and Internet characteristics. Program use was tracked, and participants were classified into five user groups (inactive to very active). Program appreciation (low, intermediate, and high) was assessed twice with an email questionnaire that was sent after the woman had received her third and sixth quiz email. Information about pregnant women and their characteristics was obtained from Dutch registries to assess representativeness of the study population.Results
About 8% of the pregnant women in the Netherlands enrolled in the program. Immigrants were underrepresented, and women with a low level of education seemed to be slightly underrepresented. Most women knew about the program from a promotional email sent by the organization (32%), followed by the Internet (22%) and midwives (16%). Women with little education were more often inactive users of the program than were highly educated women (15% vs 11%, P < .001), whereas highly educated women were more often very active users compared with women with little education (25% vs 20%, P< .001). However, women with less education were more likely than women with more education to have a high appreciation of the program after receiving three quiz emails (52% vs 44%, P = .001).Conclusions
In this real-life setting, pregnant women can be reached through an email-based health promotion program. Selective engagement by education level remains a challenge. 相似文献94.
A-M Bisgaard M Kirchhoff JE Nielsen M Kibæk A Lund M Schwartz E Christensen 《Clinical genetics》2009,75(2):175-179
A deletion on one chromosome and a mutant allele on the other may cause an autosomal recessive disease. We report on two patients with mental retardation, dysmorphic features and low catalytic activity of arylsulfatase A. One patient had a pathogenic mutation in the arylsulfatase A gene ( ARSA ) and succumbed to metachromatic leukodystrophy (MLD). The other patient had a pseudoallele, which does not lead to MLD. The presenting clinical features and low arylsulfatase A activity were explained, in each patients, by a deletion of 22q13 and, thereby, of one allele of ARSA . 相似文献
95.
Background and purpose:
In vitro evidence suggests that metabolism of anandamide by cyclooxygenase-2 (COX-2) may be more important when the primary metabolic pathway [i.e. fatty acid amide hydrolase (FAAH)] is inhibited. Thus, the first aim of the present study was to assess the effects of COX-2 and/or FAAH inhibition, on the cardiovascular actions of anandamide. The second aim was to compare the effects of anandamide with those of the metabolically stable analogue (i.e. methanandamide) and investigate mechanisms involved in responses to the latter in conscious rats.Experimental approach:
Rats were chronically instrumented for recording blood pressure, heart rate and renal, mesenteric and hindquarters vascular conductances in the freely moving state.Key results:
Inhibition of FAAH with URB597 (cyclohexycarbamic acid 3′-carbamoyl-biphenyl-3-yl-ester) augmented the haemodynamic actions of anandamide, but there was no effect of COX-2 inhibition with parecoxib, either in the absence or the presence of URB597. Methanandamide caused CB1 receptor-mediated renal and mesenteric vasoconstriction and evoked β2-adrenoceptor-mediated hindquarters vasodilatation.Conclusions and implications:
No evidence for an involvement of COX-2 in the systemic cardiovascular actions of anandamide could be demonstrated. Vasoconstrictor actions of methanandamide were shown to involve CB1 receptors, whereas no involvement of CB1 receptors in such actions of anandamide has been shown. However, β2-adrenoceptor-mediated hindquarters vasodilatation, independent of CB1 receptors, observed here with methanandamide, has previously been seen with anandamide and differs from previous results with other synthetic cannabinoids for which the response was CB1 receptor-dependent. Thus, mechanisms underlying the cardiovascular actions of endocannabinoids and synthetic analogues appear to be agonist-specific. 相似文献96.
Lin PP Jaffe N Herzog CE Costelloe CM Deavers MT Kelly JS Patel SR Madewell JE Lewis VO Cannon CP Benjamin RS Yasko AW 《Cancer》2007,109(3):603-611
BACKGROUND: Local recurrence in Ewing sarcoma is associated with a poor prognosis. The purpose of the study was to determine the factors that predict local recurrence after surgical treatment of the primary tumor. METHODS: Between 1990 and 2001, 64 patients underwent surgical resection of Ewing sarcoma. Surgical margins were assessed histologically and radiologically. Response to preoperative chemotherapy was determined by detailed specimen mapping. Local recurrence-free survival (LRFS) was calculated by Kaplan-Meier analysis. Multivariate analysis was performed with the Cox proportional hazards model. RESULTS: A number of factors were found to be associated with local recurrence on univariate analysis. Patients with a good response to chemotherapy (> or = 90% tumor necrosis), had superior LRFS at 5 years (86% vs 51%, P = .015). Central site of disease was associated with an increased rate of recurrence. The LRFS at 5 years was 50% for the chest wall, 74% for pelvic/scapular, and 86% for extremity tumors (P = .083). Positive surgical margin was not a strong predictor of recurrence (P = .72). A critical analysis of minimal surgical margin based on preoperative magnetic resonance imaging (MRI) and computed tomography (CT) scans also failed to reveal an association between margin and local recurrence. In multivariate analysis, the 2 independent predictors of local recurrence were histological response to chemotherapy and central site of disease. CONCLUSION: Local recurrence after surgical resection is a complex phenomenon. An important predictive factor is the response to chemotherapy. In the current study, this seems to have the largest impact. Central site of disease may be a second independent predictive factor. 相似文献
97.
98.
99.
Stimulus generalization of fear responses: effects of auditory cortex lesions in a computational model and in rats 总被引:3,自引:2,他引:1
Armony JL; Servan-Schreiber D; Romanski LM; Cohen JD; LeDoux JE 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(2):157-165
The conditioning of fear responses to a simple acoustic stimulus (pure
tone) paired with footshock can be mediated by the transmission of auditory
information to the lateral nucleus of the amygdala from either the auditory
thalamus or the auditory cortex. We examined the processing capacity of the
thalamo-amygdala pathway by making lesions of the auditory cortex and
testing the extent to which conditioned fear responses generalized to tones
other than the one paired with footshock. Two studies were performed, one
in an anatomically constrained computational model of the fear conditioning
network and the other in rats. Stimulus generalization was unaffected in
both. These findings support the validity of the model as an approach to
studying the neural basis of conditioned fear learning, and in addition
suggest that the thalamo-amygdala pathway, possibly by the use of
population coding, is capable of performing at least crude stimulus
discriminations.
相似文献
100.