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排序方式: 共有2597条查询结果,搜索用时 15 毫秒
41.
Alternative splicing of exon 14 determines nuclear or cytoplasmic localisation of fmr1 protein isoforms 总被引:6,自引:9,他引:6
Impaired expression of the FMR1 gene is responsible for the fragile X
mental retardation syndrome. The FMR1 gene encodes a cytoplasmic protein
with RNA-binding properties. Its complex alternative splicing leads to
several isoforms, whose abundance and specific functions in the cell are
not known. We have cloned in expression vectors, cDNAs corresponding to
several isoforms. Western blot comparison of the pattern of endogenous FMR1
proteins with these transfected isoforms allowed the tentative
identification of the major endogenous isoform as ISO 7 and of a minor band
as an isoform lacking exon 14 sequences (ISO 6 or ISO 12), while some other
isoforms (ISO 4, ISO 5) were not expressed at detectable levels.
Surprisingly, in immunofluorescence studies, the transfected splice
variants that exclude exon 14 sequences (and have alternate C-terminal
regions) were shown to be nuclear. Such differential localisation was
however not seen in subcellular fractionation studies. Analysis of various
deletion mutants suggests the presence of a cytoplasmic retention domain
encoded in exon 14 and of a nuclear association domain encoded within the
first eight exons that appear however to lack a typical nuclear
localisation signal.
相似文献
42.
43.
Needle biopsy of renal allografts: comparison of two techniques 总被引:2,自引:0,他引:2
Bogan ML; Kopecky KK; Kraft JL; Holladay AO; Filo RS; Leapman SB; Thomalla JV 《Radiology》1990,174(1):273-275
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications. 相似文献
44.
0 引言 胰腺多房性潴留性囊肿极为罕见,我科收治1例,报道如下.1 病例报告 患者,男,29岁,因发现右上腹包块11d入院,缘于11d前无明显诱因感右上腹痛,仅局限于右上腹部,无肩背部放散痛,伴间歇性发热,体温最高达38.3℃,经抗炎,对症治疗无效.并逐渐可触及右上腹有一肿块,在当地医院行穿刺检查为脓血性液体.镜检发现炎性细胞,B超示:胆囊窝下方及右肾内侧及腹腔动脉,下腔静脉外前方可见异常区,大小约9.1cm×6.6cm×7.6cm,边界清楚,形态不规则,内呈蜂窝状,可见多个大小不等的液性暗区,CT示:右上腹部上腔静脉前方6.0cm×9.0cm肿块和周围组织粘… 相似文献
45.
玻璃体切除术治疗外伤性眼内炎62例 总被引:3,自引:1,他引:2
0 引言 外伤性眼内炎是眼外伤的常见并发症 ,对视力及眼球威协极大 .由于病原体随致伤物直接进入眼内 ,在眼内和玻璃体繁殖 ,产生剧烈炎症反应 ,对眼内组织造成严重破坏 .如不及时而有效的控制 ,终使视力丧失 ,眼球萎缩 .近年随着现代玻璃体手术的发展 ,外伤性眼内炎的治愈率明显提高 .现将我科收治的 6 2例报告如下 .1 对象和方法1 .1 对象 1 996 - 0 6 / 1 998- 0 6我院连续收治 6 2例外伤性眼内炎 ,其中男 5 0例 ,女 1 2例 ,年龄 2~ 45岁 ,平均 1 6 .5岁 .1 4岁以下儿童 38例 ,占 6 1 .3% .以致伤原因分类 :角膜穿通伤30例 ,巩膜穿… 相似文献
46.
A young boy presented with an uncommon finding of impaction of upper right central incisor and transposition of canine and lateral incisor on the same side. Esthetic management of his cosmetic problem which included fixed appliance therapy followed by light cure restorations is discussed.KEY WORDS: Impaction, Transposition 相似文献
47.
为探讨体外循环(CPB)导致心脏植物神经系统(CAS)损伤的机理,了解温血心停跳液能否防止CPB后心率变异性(HRV)的降低,采用对照方法观察了温血心停跳液与冷晶体心停跳液对狗HRV的影响。结果显示:CPB后温血心停跳液组(WB组)和冷晶体心停跳液组(CC组)的全频谱(TP)、低频(LF)和高频(HF)均较术前明显降低(P<0.05),而且CC组比WB组降低更明显(P<0.05),但LF/HF在组内及组间均无明显变化(P>0.05)。CPB后24小时平均心率(MHR)明显增加(P<0.05),且CC组高于WB组(P<0.05)。本研究表明:采用温血心停跳液或冷晶体心停跳液的CPB不会干扰CAS平衡,但均能使HRV降低,温血心停跳液不能防止HRV损害。 相似文献
48.
Pedraza Gutiérrez S Coll Masfarré S Castaño Duque CH Suescún M Rovira Cañellas A 《Neuroradiology》1999,41(12):910-914
We report two cases of hyperacute spinal subdural haematoma secondary to lumbar spinal anaesthesia, identified with MRI.
Prompt diagnosis of this infrequent, potentially serious complication of spinal anaesthesia is essential, as early surgical
evacuation may be needed. Suggestive MRI findings in this early phase include diffuse occupation filling of the spinal canal
with poor delineation of the spinal cord on T1-weighted images, and a poorly-defined high-signal lesion with a low-signal
rim on T2-weighted images.
Received: 10 November 1998 Accepted: 6 April 1999 相似文献
49.
Olafsson S Berstad A Bang CJ Nysaeter G Coll P Tefera S Hatlebakk JG Hausken T Olafsson T 《Alimentary pharmacology & therapeutics》1999,13(5):651-659
BACKGROUND: We have consistently achieved about 90% eradication of H. pylori with liquid bismuth, metronidazole and oxytetracycline. AIM: To test eradication and adverse events of ranitidine bismuth citrate (RBC) when given with metronidazole and either oxytetracycline or spiramycin. METHODS: One hundred and eighty-three patients were randomized to one of four 10-day regimens: RBC400OM: RBC 400 mg b.d., oxytetracycline 500 mg q.d.s.; RBC400SM: RBC 400 mg b.d., spiramycin 1 g q.d.s.; RBC200OM: RBC 200 mg q.d.s., oxytetracycline 500 mg q.d.s.; RBC200SM: RBC 200 mg q.d.s., spiramycin 1 g q.d.s. Additionally, all patients received metronidazole 400 mg q.d.s. A 14C-urea breath test was performed at 8 weeks. RESULTS: Intention-to-treat eradication rates were 94%, 91%, 94% and 89% with RBC400OM, RBC400SM, RBC200OM and RBC200SM, respectively (P = 0.81). Eradication was significantly higher in ulcer patients (97%) than in those with diagnoses other than ulcer (86%) (P = 0.009). There was a strong tendency to better eradication among those who had never smoked (100%) compared with ex-smokers (93%) and smokers (89%) (P = 0.06). Fifty-three per cent experienced at least one moderate or severe adverse event, and women had more adverse events than men (P = 0.0002). CONCLUSIONS: All four regimens had comparable efficacy and adverse events. Eradication was significantly better in ulcer patients but there was a trend to better eradication in those who smoked less, used less alcohol and exercised more. Adverse events were frequent, perhaps because of the large dose of metronidazole used, but few patients stopped treatment. 相似文献
50.
The palpation and enucleation of occult insulinomas (less than 15 mm) can be a difficult surgical problem even with good arteriographic localization. In the authors' limited experience, confirmation of arteriographic findings by pancreatic venous sampling provided little additional localizing information. However, if arteriography is negative or equivocal, venous sampling can indicate the segment of pancreas to be "blindly" resected if the adenoma is not palpable. Venous sampling may be misleading in polyendocrine syndromes because of the frequency of multiple adenomas and variable hormone production. 相似文献