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11.

Objective

To screen mutations in FERM domain-containing protein 7 (FRMD7) gene in two Chinese families with X-linked idiopathic congenital nystagmus (XLICN).

Methods

Common ophthalmic data and peripheral blood of two Chinese XLICN families (families A and B) were collected after informed consent. Genomic DNA was prepared from the peripheral blood of members of the two families and from 100 normal controls. Mutations in the FRMD7 gene were determined by directly sequencing polymerase chain reaction (PCR) products.

Results

We identified a novel mutation c.980_983delATTA compound with c.986C>A mutation in the 11th exon of FRMD7 in family B, and a previously reported splicing mutation c.782G>C (p.R261G) in family A. The mutations were detected in patients and female carriers, while they were absent in other relatives or in the 100 normal controls.

Conclusions

Our results expand the spectrum of FRMD7 mutations in association with XLICN, and further confirm that the mutations of FRMD7 are the underlying molecular mechanism for XLICN.  相似文献   
12.
三要素法的适用对象   总被引:1,自引:0,他引:1  
指出三要素适用对象是电容电压或电感电流,而一些献对此有所误解。  相似文献   
13.
疏筋壮骨功提高人体机能的医学观察   总被引:1,自引:0,他引:1  
对28例练习疏筋壮骨功者3个月前后的部分指标进行了测定,论证了提高人体有关系统机能的方法及原因,为指导人们更好地练功提供了参考依据。  相似文献   
14.
Biochemical and biological properties of glycoconjugates are strongly determined by the specific structure of its glycan parts. Glycosylation, the covalent attachment of sugars to proteins and lipids, is very complex and highly-coordinated process involving > 250 gene products. Deficiency of glycosylation enzymes or transporters results in impaired glycosylation, and consequently pathological modulation of many physiological processes. Inborn defects of glycosylation enzymes, caused by the specific mutations, lead to the development of rare, but severe diseases - congenital disorders of glycosylation (CDGs). Up today, there are more than 45 known CDGs. Their clinical manifestations range from very mild to extremely severe (even lethal) and unfortunately, only three of them can be effectively treated nowadays. CDG symptoms highly vary, though some are common for several CDG types but also for other unrelated diseases, especially neurological ones, leaving the possibility that many CDGs cases are under- or misdiagnosed. Glycan analysis of serum transferrin (by isoelectric focusing or more sophisticated methods, such as HPLC (high-performance liquid chromatography) or MALDI (matrix-assisted laser desorption/ionization)) or serum N-glycans (by MS), enzyme activity assays and DNA sequence analysis are the most frequently used methods for CDG screening and identification, since no specific tests are available yet. In this review we summarize the current knowledge on the clinical, biochemical and genetic characteristic of distinct CDGs, as well as existing diagnostic and therapeutic procedures, aiming to contribute to the awareness on the existence of these rare diseases and encourage the efforts to elucidate its genetic background, improve diagnostics and develop new strategies for their treatment.  相似文献   
15.
介绍了符号时间序列方法,通过五组份排放分析仪瞬态检测性能对比实验,获得瞬态排放间接检测手段,控制汽油机节气门不同的开闭速度,得到不同的瞬态工况,利用Shannon熵、单缸Shannon熵和实际排放状况,确定汽油机台架实验的瞬态检测工况。  相似文献   
16.
Hermetic packaging is often an essential requirement to enable proper functionality throughout the device's lifetime and ensure the optimal performance of a micro electronic mechanical system (MEMS) device. Solid-liquid interdiffusion (SLID) bonding is a novel and attractive way to encapsulate MEMS devices at a wafer level. SLID bonding utilizes a low-melting-point metal to reduce the bonding process temperature; and metallic seal rings take out less of the valuable surface area and have a lower gas permeability compared to polymer or glass- based sealing materials. In addition, ductile metals can adopt mechanical and thermo-mechanical stresses during their service lifetime, which improves their reliability. In this study, the principles of Au-Sn and Cu-Sn SLID bonding are presented, which are meant to be used for wafer-level hermetic sealing of MEMS resonators. Seal rings in 15.24 cm silicon wafers were bonded at a width of 60 gin, electroplated, and used with Au-Sn and Cu-Sn layer structures. The wafer bonding temperature varied between 300 ℃ and 350 ℃, and the bonding force was 3.5 kN under the ambient pressure, that is, it was less than 0.1 Pa. A shear test was used to compare the mechanical properties of the interconnections between both material systems, in addition, important factors pertaining to bond ring design are discussed according to their effects on the failure mechanisms. The results show that the design ofmetal structures can significantly affect the reliability of bond rings.  相似文献   
17.
Objective: To study the clinical therapy and prognosis in children with transient congenital hypothyroidism (CH).Methods: Fifty-seven children with CH diagnosed after neonatal screening were treated with low-dosage levothyroxine (L-T4).Follow-up evaluation included the determination of TT3, TT4 and TSH serum levels and the assessment of thyroid gland morphology, bone age, growth development and development quotients (DQ). A full check-up was performed at age 2, when the affected children first discontinued the L-T4 treatment for 1 month, and one year later. Development quotients were compared (16.25±3.87) μg/d. Mean duration of therapy was (28.09±9.56) months. No significant difference was found between study group and control group in the DQ test (average score (106.58± 14.40) vs (102.4±8.6), P>0.05) and 96.49% of the CH children achieved a test score above 85. Bone age, 99mTc scans and ultrasonographic findings were all normal, and evaluation of physical development was normal too, as were the serum levels of TT3, TT4 and TSH after one year of follow-up. Conclusion: A L-T4 dosage of and physical development at age 2. So it is possible for CH children to stop taking medicine if their laboratory findings and physical development are all normal after regular treatment and 2~3 years of follow-up.  相似文献   
18.
端粒是由染色体末端的DN A重复序列组成的,其上有蛋白结合。可保护染色体免受伤害,与细胞周期过程中DN A末端片断的流失、细胞凋亡有关。端粒酶由hTERC和hTERT组成,可以维持端粒的稳定。造血干细胞有一定的端粒酶活性,目前已研究出多种因素影响其表达。端粒酶相关基因修饰干细胞可以达到建立永生化细胞系等目的,亦有很好的应用前景。最近,在研究端粒酶在人类造血系统的作用时,人们把目光集中到一种罕见的遗传病DCK上。治疗这种疾病可能需要进一步的研究来揭示hTERT的内在基因和外来因素的两种调节之间的关系。  相似文献   
19.
使用短时傅立叶变换方法处理电网暂态谐波的测量数据,并对测量系统进行了仿真测试.仿真测试结果表明,各谐波幅度的测量值与理论值相差小于5‰.  相似文献   
20.
In conjunction with thyroxine, bilirubin may play an important role for regulation of hsCRP level and a consequent pro-inflammatory condition in hypothyroidism. In present study we evaluated the dependence of hsCRP changes on total bilirubin (BT) and fT4 level in thirty overt (OH) and thirty subclinical hypothyroidism (SH). Serum BT, hsCRP, thyroxine and TSH were measured in both groups and compared with forty control subjects. Serum values of TSH, hsCRP showed raised (P < 0.001 for both) values with lower levels for fT4 and BT (P < 0.001 and 0.03 respectively) in hypothyroid patients compared to the controls. ANOVA showed significant increments in TSH and hsCRP values with decreases in fT4 among the control, SH and OH groups respectively (P < 0.001). BT values showed decrease in OH group only in comparison to controls (P = 0.04). Regression analysis revealed that hsCRP was negatively dependent on fT4 (β = −0.35, P = 0.002) and serum bilirubin (β = −0.40 and P < 0.001 respectively). Univariate general linear model analysis showed this dependence persisted even when carried out distinctly in SH and OH groups separately (P < 0.001). TSH did not show any significant predictive value on the hsCRP level in either of these two tests. From these analyses we suggest that serum hsCRP is closely integrated to a lowered synthesis of bilirubin and fT4 in hypothyroid patients. Furthermore, this causal relationship is not only limited to overt but also extends to the SH.  相似文献   
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