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排序方式: 共有370条查询结果,搜索用时 15 毫秒
11.
Hamza Shaili Elmehdi Salmani Mustapha Beraich M'hamed Taibi Mustapha Rouchdi Hamid Ez-Zahraouy Najem Hassanain Ahmed Mzerd 《RSC advances》2021,11(59):37019
The inorganic stannous-based perovskite oxide SrSnO3 has been utilized in various optoelectronic applications. Facilitating the synthesis process and engineering its properties, however, are still considered challenging due to several aspects. This paper reports on a thorough investigation of the influence of rare-earth (praseodymium) doping on the microstructural and optoelectronic properties of pure and Pr-doped SrSnO3 perovskite oxide thin films synthesized by a two-step simple chemical solution deposition route. Structural analysis indicated the high quality of the obtained phase and the alteration generated from the insertion of impurities. Surface scanning illustrated the formation of homogenous and crack-free SrSnO3 thin films with a nanorod morphology, with an augmentation in size as the dopant ratios increased. Optical properties analysis showed an enhancement in the samples optical absorption with wide-range bandgap tuning. First-principles calculations revealed the exchange interactions between the 3d–4f states and their impact on the electronic properties of the pristine material. Hall-effect measurements revealed an immense decrement in the resistivity of the films upon increment of doping ratios, passing from 7.3 × 10−2 Ω cm for the undoped sample to 4.8 × 10−2 Ω cm for 7% Pr content, while a reverse trend was observed on the carrier mobility, rising from 2.5 to 7.6 cm2 V−1 s−1 for 7% Pr content. The results emphasized the efficiency of the simple synthesis route to produce high-quality samples. The current findings will contribute to paving the way towards expanding the utilization of simple and cost-effective chemical solution deposition methods for the fast and large area growth of stannous-based perovskite oxides for optoelectronic applications.Unraveling the optical, electronic and electrical properties of high-quality nanorod morphology spray-coated Pr-doped SrSnO3 perovskite oxide thin films. 相似文献
12.
Increased frequency of congenital chromosomal aberrations in female partners of couples undergoing intracytoplasmic sperm injection 总被引:3,自引:7,他引:3
van der Ven K; Peschka B; Montag M; Lange R; Schwanitz G; van der Ven HH 《Human reproduction (Oxford, England)》1998,13(1):48-54
We evaluated the frequency of congenital chromosomal aberrations in a
sample of 305 couples included in an intracytoplasmic sperm injection
(ICSI) programme. Twenty individuals (3.3%) with congenital chromosomal
abnormalities could be identified. The following types of abnormalities
were observed: reciprocal translocations (n = 7), Robertsonian
translocations (n = 3), inversions (n = 3), other structural aberrations (n
= 4) and sex chromosome aberrations (n = 3). The rate of chromosomally
abnormal males (10/305, 3.3%) lay within the expected range for patients
with reduced semen quality. Surprisingly, 50% (10/20) of all abnormal
karyotypes were contributed by the female partner of ICSI patients. These
data confirm the higher incidence of chromosomal aberrations in infertile
populations as compared with the baseline population risk. Additionally,
the data imply that in some cases of male factor infertility a hidden
female chromosomal factor may be present, which cannot be identified by
standard clinical evaluation. In conclusion, we recommend chromosomal
analysis in both partners of couples undergoing ICSI treatment.
相似文献
13.
LEE JS IM HH JUNG Y JUNG IS JANG JY CHUN YK CHO YD KIM JO CHO JY KIM YS SHIM CS & KIM BS 《Neurogastroenterology and motility》2006,18(6):493-494
Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future. 相似文献
14.
汉语失语症患者动词功能损伤的神经语言学分析 总被引:2,自引:0,他引:2
目的:分析汉语失语症患者动词功能的损伤和临床病灶部位。方法:于2000-02/04在江苏省徐州市第一、二、三、四医院、解放军第九十七医院等大型医院入住的神经内科患者中选择6位典型的汉语失语症患者作为测查对象。采用北京医科大学汉语失语症成套测验检查法,同时参考波士顿诊断性失语检查法、西方失语症成套测验,并结合头颅CT的检查结果判断失语类型。根据本实验的目的,设计听觉路径和视觉路径两种测试方法。听觉路径通过语音来测试患者的动词功能知识(配价知识);视觉路径则是通过画面来测试患者的动词功能知识。最后,根据被试对测试的正确结果进行统计分析。结果:患者6例均进入结果分析。6例失语症患者的单宾语动词(二价动词)听觉路径成绩为:①字词层级,患者1的正确率为10%,患者2为55%,患者3为75%,患者4为60%,患者5为80%,患者6为35%。②语句层级,患者1的正确率为5%,患者2为40%,患者3为60%,患者4为55%,患者5为65%,患者6为30%。③篇章层级,患者1的正确率为5%,患者2为30%,患者3为50%,患者4为50%,患者5为60%,患者6为25%。6例失语症患者的二价动词视觉路径成绩为:①字词层级,患者1的正确率为15%,患者2为55%,患者3为80%,患者4为65%,患者5为85%,患者6为75%。②语句层级,患者1的正确率为10%,患者2为45%,患者3为65%,患者4为60%,患者5为75%,患者6为65%。③篇章层级,患者1的正确率为5%,患者2为35%,患者3为55%,患者4为50%,患者5为65%,患者6为60%。结论:汉语失语症患者的动词功能中受损伤程度最小的是该动词的基本价位,大脑对任何动词的各种论元结构变换都有极强的适应能力;左额下回后部对动词配价加工起主要作用,还涉及左额下回后部的周围区域和其他较远的相关区域。 相似文献
15.
生物制剂可用于治疗各种疾病,包括肿瘤、风湿、胃肠道疾病、皮肤科疾病、呼吸道疾病、激素缺乏症和感染。尽管近来批准了很多生物制品,但有关其药物间相互作用临床研究还不多。单克隆抗体是最主要的一类治疗性生物制品,本文介绍评价其药物间相互作用的风险评估策略,指出了评估中的关键因素,并建议将相互作用风险评估作为治疗性生物制品综合药物开发的一部分。 相似文献
16.
不同补锌方法对儿童免疫功能的影响 总被引:2,自引:0,他引:2
研究不同补锌方法(补锌,补充微量营养素,补充锌加微量营养素)改善缺锌儿童免疫功能的作用,结果显示:实验10wk后,三个实验组缺锌儿童血清锌浓度明显升高,同时淋巴细胞刺激指数明显高于对照组,流式细胞仪检测细胞周期显示对照组G0/G1期细胞增多,而实验组S+G0/G1期细胞增多,细胞处于增殖活化状态。三组中又以锌+微量营养素作用效果最好。表明:锌和微量营养素单独使用均增强缺锌儿童的免疫功能,但锌和微量 相似文献
17.
Kung FT; Chen WJ; Chou HH; Ko SF; Chang SY 《Human reproduction (Oxford, England)》1997,12(8):1649-1653
We report a rare case of early-stage endometrial adenocarcinoma in a 22
year old nullipara with polycystic ovaries undergoing conservative
treatment. Pretreatment evaluation including tumour grade, depth of
myometrial invasion, tumour size, hormone receptor status and flow
cytometric analysis indicated a favourable prognosis. The patient underwent
repeat endometrial curettage and a 6 month period of therapy with megestrol
acetate and tamoxifen. A combination contraceptive pill was then prescribed
to ensure withdrawal of the menstrual cycle thereafter. Now, 1 year after
the last curettage, there is no evidence of disease. During the treatment
period, hysteroscopy allowed for a more precise approach in panoramically
examining the tumour nest in the endometrial cavity, and the subsequent
endometrial response to hormone therapy. Laparoscopy using bulldog clamps
applied to the isthmic portion of the Fallopian tubes prevented i.p. spread
of endometrial tissue from retrograde regurgitation during hysteroscopy.
Laparoscopic ovarian electrocautery resulted in the reduction of abnormal
hypervascularization on the surface of polycystic ovaries postoperatively
but caused a peri-ovarian adhesion complication. It is interesting that
this case posed a unique opportunity to demonstrate the tumour regression
under the assistance of laparoscopy and hysteroscopy.
相似文献
18.
Identification of a gene disrupted by a microdeletion in a patient with X-linked retinitis pigmentosa (XLRP) 总被引:2,自引:2,他引:2
Roepman R; Bauer D; Rosenberg T; van Duijnhoven G; van de Vosse E; Platzer M; Rosenthal A; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(6):827-833
The gene for the most frequent from of X-linked retinitis pigmentosa
(XLRP), RP3, has been assigned by genetic and physical mapping to a segment
of less than 1000 kbp, which is flanked by the marker DXS1110 and the
ornithine transcarbamylase (OTC) gene. In search of microdeletions, we have
screened the DNA of 30 unrelated patients with XLRP by employing a
representative set of YAC-derived DNA fragments that were generated by
restriction enzyme digestion and PCR amplification. In one of these
patients, a 6.4 kbp microdeletion was detected which was not present in the
DNA of 444 male controls. A cosmid contig spanning the deletion was
constructed and used to isolate cDNAs from retina-specific libraries. Exons
corresponding to these expressed sequences as well as other putative exons
were identified by sequencing more than 30 kbp of the critical region. So
far, no point mutations in these putative exon sequences have been
identified.
相似文献
19.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献
20.
Tang RB Wang HY Lu HY Xiong J Li HH Qiu XH Liu HQ 《第二军医大学学报》2005,26(8):880-880
There have been extensive observations that RNA containing repetitive elements accumulates in transformed cells and tumor tissues. In the present study, we first obtained result consistent with previous observations by in situ hybridization. 相似文献