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1.
17α-Hydroxylase deficiency (17OHD) is a rare form of congenital adrenal hyperplasia caused by mutations in the CYP17A1 gene. This condition shows considerable clinical and biochemical variation. Molecular characterization of novel mutations in the CYP17A1 gene and detailed study of their structural, enzymatic, and clinical consequences are required to fully understand enzyme behavior. Here, we present the first molecular characterization of two novel mutations in CYP17A1 in a 15-year-old female Mexican mestizo 46,XY female with primary amenorrhea and lack of pubertal development and severe hypertension that manifested only after surgery. A complete clinical and biochemical evaluation was compatible with 17OHD. Structural anomalies in the CYP17A1 gene were discovered by direct automated sequencing, which revealed a novel compound heterozygous K110X/R362H mutation that leads to a complete lack of enzyme activity. Immunohistochemical analyses performed to determine protein expression and localization showed that cytochrome P450 17A1 was completely absent in the patient’s testicular tissue. Studies of novel mutations, such as those described here, provide important information that allows us to better understand the effect of a given mutation on enzyme function and to observe the impact of the mutation on clinical phenotype.  相似文献   
2.
Mixed gonadal dysgenesis (MGD) is a developmental anomaly in which most of the patients have a dysgenetic testis, a contralateral streak and a 45,X/46,XY karyotype. This entity involves an heterogeneous group of gonadal and phenotypic abnormalities with a wide clinical spectrum. The phenotype depends on the ratio of testicular tissue which induces virilization. Although the karyotype in these patients is 45,X/46,XY, no genotype-phenotype correlation has been found to date. Müllerian ducts persistence (MDP) in MGD is rare; however, four patients with both entities and different karyotypes have been described. Here we present the data on a newborn patient with an atypical MGD associated with MDP, two left testes, a gonadal streak on the right, and absence of Wolffian derivatives. PCR analysis identified all the Y-derived sequence tested in the father, while the patient had them all except the AZF b,c regions which were lost. FISH analysis of the paternal Y chromosome documented Yq paracentric inversion while the patient's karyotype was 45,X/46,X,idic(Yp). No mutations were observed in MIS/MISRII genes.  相似文献   
3.
Gonadoblastoma is an unusual mixed germ cell-sex cord-stromal tumor that has the potential for malignant transformation and 30% of all patients with gonadoblastoma develop germ cell tumors mainly dysgerminoma/seminoma. An additional 10% gives rise to other malignant germ cell neoplasms. This tumor affects a subset of patients with intersex disorders. The age at diagnosis is variable ranging from birth to the fourth decade, but around 94% of cases are diagnosed during the first three decades of life and there are few cases with gonadoblastoma diagnosed in infants. In this paper, we present the histological and molecular findings of four patients with gonadal dysgenesis who developed gonadoblastoma in the first 2 years of life and one case with bilateral dysgerminoma diagnosed at 15 years of age. The sex chromosomes of mosaic patients do not distribute homogenously in dysgenetic gonads; however, statistical analysis of FISH results revealed significant differences between the XY cell line in the gonadoblastoma compared with the dysgenetic testis. Our cases demonstrate that tumors could be present at a very early age, so the prophylactic removal of the gonads is advised.  相似文献   
4.
5.

Purpose

Ceramide is glycosylated to glucosylceramide or lactosylceramide, and this glycosylation is a novel multidrug-resistance (MDR) mechanism. In this work, a short-chain ceramide (C6), lactosylceramide (LacCer), and an inhibitor of ceramide glycosylation (d-threo-1-phenyl-2-decanoylamino-3-1-propanol, PDMP) were evaluated on the proliferation of cervical cancer cells. The participation of glucosylceramide synthase (GCS), P-glycoprotein (P-gp), and multidrug-resistance gene-1 (MDR-1) in the resistance to the antiproliferative effect induced by C6 was also evaluated.

Methods

Cell proliferation was determined by crystal violet staining. GCS and MDR-1 mRNA expression was evaluated by real-time RT-PCR assay. GCS and P-gp protein expressions, as well as Rhodamine 123 uptake, which is a functional test for P-gp efflux activity, were determined by flow cytometry.

Results

C6 inhibited proliferation of CaLo and CasKi cells with an IC50 of 2.5 μM; however, 50 % proliferation of ViBo cells was inhibited with 10 μM. LacCer increased the proliferation of all cells. When cells were treated with PDMP plus C6, no additional effect on antiproliferation induced by C6 was observed in CaLo and CasKi cells; however, proliferation diminished in comparison with C6 alone in ViBo cells. C6 increased GCS and MDR-1 expression in all cells, as well as P-gp expression in CasKi cells.

Conclusions

Cells that have more capacity to glycosylate ceramide and express a higher level of GCS, MDR-1, and P-gp, are more resistant to the antiproliferative effect induced by C6.  相似文献   
6.
Bioassay-guided fractionation of an EtOAc/MeOH extract of Adenaria floribunda young leaves using MCF-7, H-460, and SF-268 cancer cell lines yielded four new active compounds named adenaflorins A-D (1-4). Their chemical structures were determined by spectroscopic means. Adenaflorin A (1) was the most cytotoxic.  相似文献   
7.
Three new compounds, 2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4-oxo-4H-chromen-3-yl-4,6-bis-O-beta-D-(3,4,5-trihydroxybenzoyl)glucopyranoside (1), 5,7-dihydroxy-2-(4-hydroxyphenyl)-4-oxo-4H-chromen-3-yl-5-O-alpha-L-(3,4,5-trihydroxybenzoyl)arabinofuranoside (2), and 2-hydroxy-4-O-alpha-L-(3,5,7-trihydroxy-4-oxo-4H-chromen-2-yl)phenylarabinofuranoside (3), were isolated from the young leaves of Triplaris cumingiana, together with two known compounds, quercetin 3-O-alpha-L-(5"-O-galloyl)arabinofuranoside (4) and quercetin 3-O-beta-D-(6"-O-galloyl)glucopyranoside (5). The structures of 1-3 were established by spectroscopic methods. Compounds 1-5 were evaluated for their cytotoxic activities against the MCF-7, H-460, and SF-268 human cancer cell lines.  相似文献   
8.
We developed the Quality of Contraceptive Counseling (QCC) Scale to improve measurement of client experiences with providers in the era of rights‐based service delivery. We generated scale items drawing on the previously published QCC Framework and qualitative research on women's preferences for counseling in Mexico, and refined them through cognitive interviews (n = 29) in two Mexican states. The item pool was reduced from 35 to 22 items after pilot testing using exit interviews in San Luis Potosí (n = 257). Exploratory Factor Analysis revealed three underlying dimensions (Information Exchange, Interpersonal Relationship, Disrespect and Abuse); this dimensionality was reproduced in Mexico City (n = 242) using Confirmatory Factor Analysis. Item Response Theory analyses confirmed acceptable item properties in both states, and correlation analyses established convergent, predictive, and divergent validity. The QCC Scale and subscales fill a gap in measurement tools for ensuring high quality of care and fulfillment of human rights in contraceptive services, and should be evaluated and adapted in other contexts.  相似文献   
9.
BackgroundEpstein-Barr virus (EBV) is a member of the Herpesviridae family and is associated with Hodgkin lymphoma (HL). Isolates of EBV are classified according to sequence variation in the latency genes such as Epstein-Barr virus nuclear antigen (EBNA). EBNA2 contains the most divergent locus and is classified into type 1 and type 2 or EBNA2A and EBNA2B, respectively. We compared the frequency of EBV and the distribution of EBNA genotypes in Mexican children and adults with HL.Patients and MethodsLymph node biopsy specimens from children and adults with HL were embedded in paraffin. EBV was identified by LMP1 amplification and Epstein-Barr–encoded RNA EBER by in situ hybridization (ISH) and genotyped as EBNA2A or EBNA2B using nested polymerase chain reaction (PCR) and specific primers for the detection of subtype.ResultsSixty-six samples were obtained from 3 hospitals—42 (63%) from children and 24 (37%) from adults with HL. Thirty-two of the 42 samples (76.1%) were positive for EBV in children and 16 of 24 (66.6%) samples were positive in adults (P = .41). In both children and adults, EBV was found more frequently in male patients. Thirty-four of 48 cases could be typed (70.8%). EBNA2A was found in 7/21 (33.3%) children and in 4/13 (30.8%) adults (P = 1.0), and EBNA2B was found in 10/21 (47.6%) children and in 9/13 (69.2%) adults (P = .22). A mix of subtypes was found in 4/21 (19%) children.ConclusionEBV was found frequently in both children and adults with HL. EBNA2B was the most frequent subtype, and a high frequency of mixed subtypes was found in children.  相似文献   
10.
Gonadoblastoma (GB) is an in situ tumor consisting of a heterogeneous population of mature and immature germ cells, other cells resembling immature Sertoli/granulosa cells, and Leydig/lutein-like cells, may also be present. GB almost exclusively affects a subset of patients with intersex disorders and in 30% of them overgrowth of the germinal component of the tumor is observed and the lesion is term dysgerminoma/seminoma. Several pathways have been proposed to explain the malignant process, and abnormal OCT3/4 expression is the most robust risk factor for malignant transformation. Some authors have suggested that OCT3/4 and beta-catenin might both be involved in the same oncogenic pathway, as both genes are master regulators of cell differentiation and, overexpression of either gene may result in cancer development. The mechanism by which beta-catenin participates in GB transformation is not completely clear and exploration of the E-cadherin pathway did not conclusively show that this pathway participated in the molecular pathogenesis of GB. Here we analyze seven patients with mixed gonadal dysgenesis and GB, in an effort to elucidate the participation of beta-catenin and E-cadherin, as well as OCT3/4, in the oncogenic pathways involved in the transformation of GB into seminoma/dysgerminoma. We conclude that the proliferation of immature germ cells in GB may be due to an interaction between OCT3/4 and accumulated beta-catenin in the nuclei of the immature germ cells.  相似文献   
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