全文获取类型
收费全文 | 527篇 |
免费 | 11篇 |
国内免费 | 1篇 |
出版年
2022年 | 4篇 |
2021年 | 6篇 |
2020年 | 7篇 |
2019年 | 4篇 |
2017年 | 8篇 |
2016年 | 15篇 |
2015年 | 10篇 |
2014年 | 14篇 |
2013年 | 16篇 |
2012年 | 16篇 |
2011年 | 16篇 |
2010年 | 19篇 |
2009年 | 19篇 |
2008年 | 23篇 |
2007年 | 22篇 |
2006年 | 17篇 |
2005年 | 18篇 |
2004年 | 20篇 |
2003年 | 17篇 |
2002年 | 15篇 |
2001年 | 16篇 |
2000年 | 19篇 |
1999年 | 12篇 |
1992年 | 4篇 |
1991年 | 11篇 |
1990年 | 13篇 |
1989年 | 14篇 |
1988年 | 18篇 |
1987年 | 14篇 |
1986年 | 12篇 |
1985年 | 11篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 4篇 |
1976年 | 2篇 |
1975年 | 5篇 |
1974年 | 11篇 |
1973年 | 7篇 |
1972年 | 9篇 |
1971年 | 10篇 |
1970年 | 4篇 |
1969年 | 7篇 |
1968年 | 7篇 |
1967年 | 4篇 |
1966年 | 4篇 |
排序方式: 共有539条查询结果,搜索用时 125 毫秒
161.
Bakharev N. N. Balachenkov I. M. Chernyshev F. V. Chugunov I. N. Dyachenko V. V. Gusev V. K. Iliasova M. V. Khilkevitch E. M. Khromov N. A. Kiselev E. O. Konovalov A. N. Kurskiev G. S. Minaev V. B. Melnik A. D. Miroshnikov I. V. Novokhatsky A. N. Patrov M. I. Petrov Yu. V. Sakharov N. V. Shchegolev P. B. Shevelev A. E. Skrekel O. M. Telnova A. Yu. Tokarev V. A. Tolstyakov S. Yu. Tukhmeneva E. A. Varfolomeev V. I. Voronin A. V. 《Plasma Physics Reports》2020,46(7):675-682
Plasma Physics Reports - Globus-M2—a new 1-Tesla spherical tokamak—was recently launched. The main features and research directions of this machine in scope of fusion–fission... 相似文献
162.
Tal Burt Savita Dhillon Pooja Sharma Danish Khan Deepa MV Sazid Alam Sarika Jain Bhavana Alapati Sanjay Mittal Padam Singh 《PloS one》2013,8(7)
Background
A public that is an informed partner in clinical research is important for ethical, methodological, and operational reasons. There are indications that the public is unaware or misinformed, and not sufficiently engaged in clinical research but studies on the topic are lacking. PARTAKE – Public Awareness of Research for Therapeutic Advancements through Knowledge and Empowerment is a program aimed at increasing public awareness and partnership in clinical research. The PARTAKE Survey is a component of the program.Objective
To study public knowledge and perceptions of clinical research.Methods
A 40-item questionnaire combining multiple-choice and open-ended questions was administered to 175 English- or Hindi-speaking individuals in 8 public locations representing various socioeconomic strata in New Delhi, India.Results
Interviewees were 18–84 old (mean: 39.6, SD±16.6), 23.6% female, 68.6% employed, 7.3% illiterate, 26.3% had heard of research, 2.9% had participated and 58.9% expressed willingness to participate in clinical research. The following perceptions were reported (% true/% false/% not aware): ‘research benefits society’ (94.1%/3.5%/2.3%), ‘the government protects against unethical clinical research’ (56.7%/26.3%/16.9%), ‘research hospitals provide better care’ (67.2%/8.7%/23.9%), ‘confidentiality is adequately protected’ (54.1%/12.3%/33.5%), ‘participation in research is voluntary’ (85.3%/5.8%/8.7%); ‘participants treated like ‘guinea pigs’’ (20.7%/53.2%/26.0%), and ‘compensation for participation is adequate’ (24.7%/12.9%/62.3%).Conclusions
Results suggest the Indian public is aware of some key features of clinical research (e.g., purpose, value, voluntary nature of participation), and supports clinical research in general but is unaware of other key features (e.g., compensation, confidentiality, protection of human participants) and exhibits some distrust in the conduct and reporting of clinical trials. Larger, cross-cultural surveys are required to inform educational programs addressing these issues. 相似文献163.
164.
Anedchenko EA Kiseleva NP Dmitriev AA Kiselev FL Zabarovskiĭ ER Senchenko VN 《Molekuliarnaia biologiia》2007,41(1):86-95
In this work for the first time copy number and expression changes of the tumor suppressor gene RBSP3 (3p21.3) were investigated. The study was performed on HPV-positive squamous cervical carcinoma (SCC) using real-time PCR. Deletions were detected in 42% of cases (19 of 45 studied biopsies). Frequency of deletions was significantly higher in SCC samples with metastases (64%) than in tumors without metastases (32%, P < 0.05). In a few cases amplification of RBSP3 was also found. Altogether copy number changes of RBSP3 were detected in 51% of cases (23 of 45). Expression of RBSP3 was decreased in 64% of SCC samples (21 of 33). Again decreased expression of RBSP3 was detected significantly more frequently (83%) in tumors with metastases compared with SCC without metastases (52%, P < 0.05). In several cases however increased expression was observed. Altogether changes in expression of RBSP3 were detected in 79% (26 of 33) of SCC biopsies. Comparison of copy number and expression changes showed that in 23% of SCC cases decreased expression of RBSP3 was detected in samples with deletions and in 36% cases such decrease was not associated with copy number changes. Rarely more complicated SCC cases were found. For example in some tumors increased expression of RBSP3 was detected in samples with deletions or without changes in copy number. Results of the study suggested that RBSP3 is involved in the progression of SCC and complex mechanisms for inactivation of RBSP3. We also hypothesize that these data indicate that RBSP3 in addition to dephosphorylation of pRb has other functions important for malignant transformation because pRb is almost absent in HPV-positive SCC. 相似文献
165.
Kiselev AV Il'ina PL Egorova AA Baranov AN Gur'ianov IA Baianova NV Tarasenko II Lesina EA Vlasov GP Baranov VS 《Genetika》2007,43(6):725-733
Asymmetrical lysine dendrimers are promising as vectors for delivering gene expression constructs into mammalian cells. The condensing, protective, and transfection properties were studied for pentaspherical lysine dendrimer D5 and its analog D5C10, modified with capric acid residues at the outer sphere; in addition, the transfection activity was assayed for complexes DNA-dendrimer-endosomolytic peptide JTS-1. Fatty acid residues incorporated in lysine dendrimers proved to improve their ability to bind DNA, to protect DNA from nuclease degradation, and to ensure its transfer into the nucleus. Peptide JTS-1 introduced in DNA-dendrimer complexes significantly increased their transfection activity. The potentiating effect of JTS-1 was especially high with the DNA-D5C10 complex. An excess of JTS-1 changed the structure of the complexes and reduced their transfection activity. It was assumed that dendrimers D5 and D5C10 are promising vectors for delivering DNA to eukaryotic cells and provide a basis for constructing more refined nonvirus module carriers. 相似文献
166.
Magnetic resonance imaging (MRI) was carried out in 24 patients with thoracic osteochondrosis. The obtained MR images showed the high efficiency of this radiodiagnostic technique in solving the tasks of visualizing a degenerative-dystrophic lesion of the vertebral column. MRI allows one to solve a broad spectrum of specific problems facing a radiodiagnostician and a neurosurgeon on examining a patient with thoracic osteochondrosis. This study permits an objective assessment of the stage of herniation and the degree of spinal cord compression, determination of treatment policy, planning of a surgical intervention, assessment of the results of surgical treatment, timely detection of possible complications, and visualization of recurrent hernia. 相似文献
167.
168.
169.
170.