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排序方式: 共有3193条查询结果,搜索用时 9 毫秒
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2.
Carrier diagnosis of Duchenne muscular dystrophy using restriction fragment length polymorphisms 总被引:6,自引:0,他引:6
Molecular probes that are tightly linked to and flank the Duchenne muscular dystrophy (DMD) locus, have been used to characterize DMD mutations and diagnose female carriers. Deletions within the Xp21 region were identified for 8 of 71 families studied. Using both DNA and CK studies, accurate (96 to 98%) carrier or noncarrier diagnoses were made for 51 of 75 females at risk in 24 families with a single affected male. DNA studies resulted in an alteration of predicted risk in 40% of the cases. Recombinant diagnostic methods are useful for carrier detection in families with one or more affected males. 相似文献
3.
Jing‐Long Huang Liang‐Shiou Ou Ching‐Hsiung Tsao Li‐Chen Chen Ming‐Ling Kuo 《Pediatric allergy and immunology》2002,13(6):426-433
T lymphocytes play a fundamental role in the initiation and regulation of chronic inflammatory responses in patients with asthma. CD69 is an early marker of T‐cell activation. The levels of intercellular adhesion molecule‐1 (ICAM‐1, CD54) and L ‐selectin have been reported to increase in patients with allergic diseases and asthma. The present study was therefore undertaken to investigate the expression of CD69, CD54, and L ‐selectin by T lymphocytes of children with asthma, before and after immunotherapy. Eighteen children newly diagnosed with asthma, 11 good and nine poor responders to immunotherapy, and 16 normal subjects, were enrolled in this study. The percentages of CD69+, CD54+, and CD62L+ cells in T lymphocytes were measured by using flow cytometry. The levels of CD69, CD54, and CD62L in serum and culture supernatants were determined by using enzyme‐linked immunosorbent assay (ELISA). The expression of CD69 and CD54 on CD3+ T lymphocytes was significantly higher in children with asthma than in control patients. All the patient groups expressed (spontaneously and following stimulation with phorbol myristate acetate and ionomycin together with mite‐extract proteins) greater amounts of CD69 and CD54 than did control subjects. With long‐term immunotherapy, the percentages of CD69+ and CD54+ T lymphocytes were significantly lower in patients with a good response to immunotherapy. Our results also showed significantly lower serum L ‐selectin levels following immunotherapy. In conclusion, successful immunotherapy resulted in decreased expression and production of CD69 and CD54. These results may explain, in part, the clinical efficacy of immunotherapy. 相似文献
4.
Activated neutrophils aggravate endothelial dysfunction after reperfusion of the ischemic feline myocardium. 总被引:3,自引:0,他引:3
Endothelial dysfunction, as evidenced by decreased stimulated release of endothelium-derived relaxing factor (EDRF), occurs after reperfusion of the ischemic myocardium. To better understand this endothelial dysfunction, isolated cat hearts were perfused under constant flow by the Langendorff procedure with Krebs-Henseleit solution devoid of blood cells. Following global ischemia (90 minutes) and reperfusion (20 minutes), coronary vasorelaxation to the endothelium-dependent vasodilator acetylcholine (ACh) was 70 +/- 3% of initial values (p less than 0.01) compared with 90 +/- 4% in nonischemic control perfused hearts. No decrement occurred in response to the endothelium-independent vasodilator nitroglycerin (NTG). Coronary artery rings isolated from the ischemic left circumflex coronary artery showed a similar degree of endothelial dysfunction to ACh, with normal relaxation in response to NaNO2. Autologous cat neutrophils (100 million cells), activated with 100 nmol/L f-met-leu-phe infused into the heart directly before and throughout reperfusion, resulted in a further decrement in ACh-induced vasodilation, to 55 +/- 5% of initial response, with no effect on NTG-induced vasodilation. Similar results were obtained with coronary artery rings isolated from perfused cat hearts and exposed to neutrophils. This neutrophil-enhanced endothelial dysfunction was inhibited by human superoxide dismutase as well as by an antibody to the adherence glycoprotein complex CD-18 (i.e., MAbR 15.7). Therefore endothelial dysfunction occurs initially upon reperfusion of the previously ischemic heart and is aggravated by superoxide radicals produced by activated neutrophils. 相似文献
5.
Monoclonal antibody K1 reacts with epithelial mesothelioma but not with lung adenocarcinoma. 总被引:8,自引:0,他引:8
K Chang L H Pai H Pass H W Pogrebniak M S Tsao I Pastan M C Willingham 《The American journal of surgical pathology》1992,16(3):259-268
Immunoperoxidase histochemical staining of cryostat sections from human tumor tissues revealed that a murine monoclonal antibody (MAb), K1, can distinguish epithelial mesotheliomas from lung adenocarcinomas. All of 15 epithelial-type mesotheliomas and all four mixed type mesothelioma samples, but none of 23 lung adenocarcinomas with different degrees of histologic differentiation demonstrated reactivity with antibody K1. Of the cell populations in each mesothelioma tested, 80% to 100% showed strong and homogeneous staining with MAb K1. Immunofluorescence analysis of live cultured cells from an epithelioid mesothelioma (H-meso) and several lung carcinoma cell lines as well as a pleural effusion of a patient with mesothelioma also showed selective reactivity of K1 with the mesothelioma cells. These data indicate that K1 can be useful as a mesothelial cell marker for the differential pathological diagnosis of the epithelial form of mesothelioma; K1 may also be useful in the study of the pathogenesis, immunodiagnosis, and immunotherapy of epithelial-type and mixed-type human malignant mesothelioma. 相似文献
6.
目的:对临床确诊糖尿病患同时测定血清葡萄糖(Glu)及糖化血清蛋白(GSP)的含量,观察二的关系,以及糖化血清蛋白水平对于评价近期(2—3周)糖尿病患血糖在体内变化的临床意义进行了观察。方法:血清葡萄糖、糖化血清蛋白测定均采用酶法测定。结果:178例糖尿病患Glu、GSP均正常3l例占17.4%;Glu、GSP均增高107例占60.1%;Glu正常、GSP增高15例占8.43%;Glu增高、GSP正常25例占14%。结论:糖化血清蛋白的含量不受即时血糖的影响,二的变化不成比例性,对评价糖尿病患2~3周病情的控制是一项灵敏可靠的指标,尤其对于住院病人的治疗与监控有一定的意义。 相似文献
7.
In vitro metabolic study of temsirolimus: preparation, isolation, and identification of the metabolites. 总被引:1,自引:0,他引:1
The in vitro metabolism of temsirolimus, (rapamycin-42-[2,2-bis-(hydroxymethyl)]-propionate), an antineoplastic agent, was studied using human liver microsomes as well as recombinant human cytochrome P450s, namely CYP3A4, 1A2, 2A6, 2C8, 2C9, 2C19, and 2E1. Fifteen metabolites were detected by liquid chromatography (LC)-tandem mass spectrometry (MS/MS or MS/MS/MS). CYP3A4 was identified as the main enzyme responsible for the metabolism of the compound. Incubation of temsirolimus with recombinant CYP3A4 produced most of the metabolites detected from incubation with human liver microsomes, which was used for large-scale preparation of the metabolites. By silica gel chromatography followed by semipreparative reverse-phase high-performance liquid chromatography, individual metabolites were separated and purified for structural elucidation and bioactivity studies. The minor metabolites (peaks 1-7) were identified as hydroxylated or desmethylated macrolide ring-opened temsirolimus derivatives by both positive and negative mass spectrometry (MS) and MS/MS spectroscopic methods. Because these compounds were unstable and only present in trace amounts, no further investigations were conducted. Six major metabolites were identified as 36-hydroxyl temsirolimus (M8), 35-hydroxyl temsirolimus (M9), 11-hydroxyl temsirolimus with an opened hemiketal ring (M10 and M11), N- oxide temsirolimus (M12), and 32-O-desmethyl temsirolimus (M13) using combined LC-MS, MS/MS, MS/MS/MS, and NMR techniques. Compared with the parent compound, these metabolites showed dramatically decreased activity against LNCaP cellular proliferation. 相似文献
8.
Meng-Luen Lee Hsiao-Neng Chen Ming Chen Lon-Yen Tsao Bao-Tyan Wang Mei-Hui Lee Ing-Sh Chiu 《台湾医志》2006,105(4):284-289
BACKGROUND: Chromosome 22q11.2 deletion is frequently associated with conotruncal malformations and aortic arch anomalies. This study investigated the association of chromosome 22q11.2 deletion with clinical manifestations in four pediatric patients with persistent fifth aortic arch. METHODS: Four patients with persistent fifth aortic arch treated between July 1997 and June 2004 were included in this retrospective study. There were two girls and two boys, aged 2 days to 11.3 years, with persistent fifth aortic arch and cardiac conotruncal malformations. Chart recordings, plain chest films, two-dimensional and Doppler echocardiograms, cardiac catheterization with angiograms, surgical findings, and cytogenetic study were analyzed. RESULTS: Clinically, all four patients had the cardinal phenotypic features of 22q11.2 deletion syndrome, including cardiovascular malformations (conotruncal malformations and aortic arch anomalies), abnormal facies, thymic hypoplasia, canopy anomaly of the palate (high-arched palate, rather than cleft palate), and hypocalcemia (or hypoparathyroidism). All four patients were confirmed to have chromosome 22q11.2 deletion. CONCLUSION: Congenital conotruncal malformations, including tetralogy of Fallot with pulmonary atresia or stenosis, and aortic arch anomalies including a persistent fifth aortic arch or a right aortic arch, should lead to suspicion of chromosome 22q11.2 deletion when manifested together with any one of the other four cardinal phenotypic features. 相似文献
9.
10.
Accelerating cardiac cine 3D imaging using k-t BLAST. 总被引:1,自引:0,他引:1
Sebastian Kozerke Jeffrey Tsao Reza Razavi Peter Boesiger 《Magnetic resonance in medicine》2004,52(1):19-26
By exploiting spatiotemporal correlations in cardiac acquisitions using k-t BLAST, gated cine 3D acquisitions of the heart were accelerated by a net factor of 4.3, making single breathhold acquisitions possible. Sparse sampling of k-t space along a sheared grid pattern was implemented into a cine 3D SSFP sequence. The acquisition of low-resolution training data, which was required to resolve aliasing in the k-t BLAST method, was either interleaved into the sampling process or obtained in a separate prescan to allow for shorter breathhold durations in patients with heart disease. Volumetric datasets covering the heart with 20 slices at a spatial resolution of 2 x 2 x 5 mm3 were recorded with 20 cardiac phases in a total breathhold duration of 25-27 sec, or 18 sec if partial Fourier sampling was additionally employed. The feasibility of the method was demonstrated on healthy volunteers and on patients. The comparison of endocardial area derived from single slices of the 3D dataset with values extracted from separate single-slice acquisitions showed no significant differences. By shortening the acquisition substantially, k-t BLAST may greatly facilitate volumetric imaging of the heart for evaluation of regional wall motion and the assessment of ventricular volume and ejection fraction. 相似文献