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排序方式: 共有543条查询结果,搜索用时 343 毫秒
161.
Nechiporuk T; Huynh DP; Figueroa K; Sahba S; Nechiporuk A; Pulst SM 《Human molecular genetics》1998,7(8):1301-1309
Spinocerebellar ataxia type 2 (SCA2) is caused by expansion of a CAG
trinucleotide repeat located in the coding region of the human SCA2 gene.
Sequence analysis revealed that SCA2 is a novel gene of unknown function.
In order to provide insights into the molecular mechanisms of pathogenesis
of SCA2 and to identify conserved domains, we isolated and characterized
the mouse homolog of the SCA2 gene. Sequence and amino acid analysis
revealed 89% identity at the nucleotide and 91% identity at the amino acid
level. However, there was no extended polyglutamine tract in the mouse SCA2
cDNA, suggesting that the normal function of SCA2 is not dependent on this
domain. Northern blot analysis of different mouse tissues indicated that
the mouse SCA2 gene was expressed in most tissues, but at varying levels.
Alternative splicing seen in human SCA2 was conserved in the mouse. By
northern blot analysis, SCA2 was expressed during embryogenesis as early as
day 8 of gestation (E8). Immunohistochemical staining using
affinity-purified antibodies demonstrated that ataxin 2 was expressed in
the cytoplasm of Purkinje cells as well as in other neurons of the CNS.
相似文献
162.
Initiation of periovulatory events in gonadotrophin-stimulated macaques with varying doses of recombinant human chorionic gonadotrophin 总被引:2,自引:3,他引:2
Zelinski-Wooten MB; Hutchison JS; Trinchard-Lugan I; Hess DL; Wolf DP; Stouffer RL 《Human reproduction (Oxford, England)》1997,12(9):1877-1885
During in-vitro fertilization (IVF) cycles, a large bolus of human
chorionic gonadotrophin (HCG) is used to induce periovulatory events, but
the efficacy of lower doses is undefined. Following follicular stimulation
in rhesus monkeys, oocyte nuclear maturation, IVF, granulosa cell
luteinization and corpus luteum function were compared after injection of
100, 300 or 1000 IU recombinant HCG or 1000 IU urinary HCG. Bioactive HCG
rose to peak concentrations within 2 h that were proportional to the dose
administered (100 < 300 < 1000 IU, recombinant HCG = urinary HCG).
The duration of surge values (>100 ng/ml) was also dose-dependent (0 h,
100 IU; 24 h, 300 IU; >48 h, 1000 IU, recombinant and urinary HCG).
While the proportions of oocytes resuming meiosis and undergoing IVF were
similar among groups, fewer animals yielded fertilizable oocytes following
100 and 300 IU (five of nine) compared to 1000 IU recombinant and urinary
HCG (nine of 10). Peak values of serum progesterone in the luteal phase
were similar, but declined 2 days earlier after 100 and 300 IU relative to
1000 IU recombinant and urinary HCG. Thus, 3-10 fold lower doses of HCG
elicit low amplitude surges of short duration that induce periovulatory
events such as re-initiation of oocyte meiosis and granulosa cell
luteinization. However, oocyte fertilization and luteal function may
optimally require surges of higher amplitude and longer duration similar to
those produced by standard doses of 1000 IU recombinant or urinary HCG.
相似文献
163.
Expression of angiotensin AT(1) and AT(2) receptors in adult rat cardiomyocytes after myocardial infarction. A single-cell reverse transcriptase-polymerase chain reaction study 下载免费PDF全文
Busche S Gallinat S Bohle RM Reinecke A Seebeck J Franke F Fink L Zhu M Sumners C Unger T 《The American journal of pathology》2000,157(2):605-611
164.
Close mapping of the focal non-epidermolytic palmoplantar keratoderma (PPK) locus associated with oesophageal cancer (TOC) 总被引:1,自引:1,他引:1
Kelsell DP; Risk JM; Leigh IM; Stevens HP; Ellis A; Hennies HC; Reis A; Weissenbach J; Bishop DT; Spurr NK; Field JK 《Human molecular genetics》1996,5(6):857-860
Focal non-epidermolytic palmoplantar keratoderma (PPK or palmoplantar
ectodermal dysplasia type III) is associated with oesophageal cancer in
three families: two large pedigrees located in Liverpool, UK and in the
midwestern American states and one smaller family from Germany. In these
families, the PPK is inherited as autosomal dominant and has a late onset,
usually manifesting between 7 and 8 years of age. The disease is
characterised by thickening of the pressure areas of the soles, but is not
restricted to the feet and also presents with oral leukokeratosis and
follicular hyperkeratosis. The disease locus [previously termed the
"tylosis oesophageal cancer gene' (TOC) locus] has been mapped to
17q23-qter by linkage analysis. This region is located telomeric to the
keratin 16 gene, in which mutations have been identified in focal PPK
families who show no increased cancer risk. We describe the close mapping
of this locus to the interval between AFMb054zf9 and D17S1603 using
haplotype analysis of additional Genethon markers in the region and show
that although the American family is unlikely to be related to either of
the other two, the UK and German pedigrees may share a common descent. This
work provides a basis for positional cloning and candidate gene analysis in
order to identify a gene that may be involved in familial oesophageal
cancer.
相似文献
165.
Cuendet GS; Loten EG; Cameron DP; Renold AE; Marliss EB 《The American journal of physiology》1975,228(1):276-283
166.
167.
168.
Acoustic neuromas: Gd-DTPA enhancement in MR imaging 总被引:1,自引:0,他引:1
Magnetic resonance (MR) imaging examinations were performed in ten patients with 12 acoustic neuromas before and after intravenous administration of 0.1 mmol/kg body weight gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA). The degree of enhancement was greatest with the inversion recovery sequence 1,500/500/44 (repetition time [TR]/inversion time/echo delay time [TE]), followed by spin-echo (SE) 544/44 (TR/TE) sequences, then by SE 1,500/44 and SE 1,500/80 sequences. After enhancement there was a 50% reduction for measured T1 values, 33% for T2, and no significant change for proton density. There were no toxic effects on patients. Enhanced CT scans failed to demonstrate lesions in six of 12 cases. Air-CT technique improved sensitivity in four of five cases. Enhanced MR imaging added significant clinical information in two small intracanalicular tumors and in one recurrent tumor. 相似文献
169.
170.
Abdominal computed tomography (CT) scans of 55 patients who had ingested Gastrografin (meglumine diatrizoate and diatrizoate sodium) diluted to 2% with tap water and flavored with a commercial fruit juice base were reviewed. Twenty patients (36%) demonstrated intraluminal precipitation of Gastrografin shown by focal areas of markedly increased attenuation within the gastric lumen or trapped within gastric folds. Beam-hardening artifact produced by precipitation was observed, which limited the diagnostic value of some examinations. In vitro CT scans of the same Gastrografin solution titrated with hydrochloric acid or sodium hydroxide showed that by raising the pH of the solution, precipitation was virtually eliminated. Fifty-one CT scans of the abdomen using a buffered Gastrografin solution demonstrated precipitation in only five patients. Properly buffered dilute oral Gastrografin solutions should significantly decrease the prevalence of precipitation during abdominal CT examinations. 相似文献