全文获取类型
收费全文 | 5686篇 |
免费 | 420篇 |
国内免费 | 85篇 |
专业分类
耳鼻咽喉 | 74篇 |
儿科学 | 202篇 |
妇产科学 | 82篇 |
基础医学 | 952篇 |
口腔科学 | 81篇 |
临床医学 | 552篇 |
内科学 | 1187篇 |
皮肤病学 | 120篇 |
神经病学 | 553篇 |
特种医学 | 332篇 |
外科学 | 725篇 |
综合类 | 54篇 |
现状与发展 | 2篇 |
预防医学 | 274篇 |
眼科学 | 111篇 |
药学 | 441篇 |
中国医学 | 44篇 |
肿瘤学 | 405篇 |
出版年
2023年 | 51篇 |
2022年 | 153篇 |
2021年 | 256篇 |
2020年 | 122篇 |
2019年 | 175篇 |
2018年 | 165篇 |
2017年 | 135篇 |
2016年 | 177篇 |
2015年 | 243篇 |
2014年 | 298篇 |
2013年 | 338篇 |
2012年 | 483篇 |
2011年 | 463篇 |
2010年 | 256篇 |
2009年 | 206篇 |
2008年 | 318篇 |
2007年 | 302篇 |
2006年 | 301篇 |
2005年 | 208篇 |
2004年 | 219篇 |
2003年 | 142篇 |
2002年 | 154篇 |
2001年 | 110篇 |
2000年 | 100篇 |
1999年 | 82篇 |
1998年 | 47篇 |
1997年 | 35篇 |
1996年 | 30篇 |
1995年 | 35篇 |
1994年 | 28篇 |
1993年 | 21篇 |
1992年 | 39篇 |
1991年 | 43篇 |
1990年 | 47篇 |
1989年 | 50篇 |
1988年 | 19篇 |
1987年 | 32篇 |
1986年 | 33篇 |
1985年 | 31篇 |
1984年 | 23篇 |
1983年 | 19篇 |
1979年 | 19篇 |
1976年 | 11篇 |
1973年 | 11篇 |
1972年 | 15篇 |
1971年 | 18篇 |
1970年 | 14篇 |
1969年 | 13篇 |
1968年 | 10篇 |
1966年 | 12篇 |
排序方式: 共有6191条查询结果,搜索用时 15 毫秒
141.
A novel technique using three‐dimensionally documented biopsy mapping allows precise re‐visiting of prostate cancer foci with serial surveillance of cell cycle progression gene panel
下载免费PDF全文
![点击此处可从《The Prostate》网站下载免费的PDF全文](/ch/ext_images/free.gif)
142.
143.
144.
Soo-Jung So Heon-Jeong Lee Seung-Gul Kang Chul-Hyun Cho Ho-Kyoung Yoon Leen Kim 《Psychiatry investigation》2015,12(2):183-189
ObjectiveTo investigate the personality characteristics of patients with upper airway resistance syndrome (UARS) and those of patients with obstructive sleep apnea syndrome (OSAS).MethodsEighty-eight patients with UARS and 365 patients with OSAS participated. All patients had a diagnostic full-night attended polysomnography (PSG) and completed the Athens Insomnia Scale (AIS), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Symptom Checklist-90-Revision (SCL-90-R) and Eysenck Personality Questionnaire (EPQ).ResultsThe UARS group scored significantly higher than the OSAS group on the ESS, AIS, and PSQI (p<0.001). The scores of all SCL-90-R subscales in the UARS group were significantly higher than those in the OSA group (all p<0.001, except for somatization, p=0.016). Patients with UARS scored lower on EPQ-E (extroversion/introversion) (p=0.006) and EPQ-L (lie) (p<0.001) than those with OSA. UARS patients also showed higher scores on EPQ-P (psychoticism) (p=0.002) and EPQ-N (neuroticism) (p<0.001) than OSAS patients.ConclusionOur results suggest that patients with UARS have worse subjective sleep quality than OSAS patients in spite of their better PSG findings. UARS patients tend to have more neurotic and sensitive personalities than patients with OSAS, which may be a cause of the clinical features of UARS. 相似文献
145.
Plasminogen activation in synovial tissues: differences between normal, osteoarthritis, and rheumatoid arthritis joints 总被引:12,自引:3,他引:12
下载免费PDF全文
![点击此处可从《Annals of the rheumatic diseases》网站下载免费的PDF全文](/ch/ext_images/free.gif)
OBJECTIVE—To analyse the functional activity of the plasminogen activators urokinase (uPA) and tissue type plasminogen activator (tPA) in human synovial membrane, and to compare the pattern of expression between normal, osteoarthritic, and rheumatoid synovium. The molecular mechanisms underlying differences in PA activities between normal and pathological synovial tissues have been further examined.
METHODS—Synovial membranes from seven normal (N) subjects, 14 osteoarthritis (OA), and 10 rheumatoid arthritis (RA) patients were analysed for plasminogen activator activity by conventional zymography and in situ zymography on tissue sections. The tissue distribution of uPA, tPA, uPA receptor (uPAR), and plasminogen activator inhibitor type-1 (PAI-1) was studied by immunohistochemistry. uPA, tPA, uPAR, and PAI-1 mRNA values and mRNA distribution were assessed by northern blot and in situ hybridisations respectively.
RESULTS—All normal and most OA synovial tissues expressed predominantly tPA catalysed proteolytic activity mainly associated to the synovial vasculature. In some OA, tPA activity was expressed together with variable amounts of uPA mediated activity. By contrast, most RA synovial tissues exhibited considerably increased uPA activity over the proliferative lining areas, while tPA activity was reduced when compared with N and OA synovial tissues. This increase in uPA activity was associated with increased levels of uPA antigen and its corresponding mRNA, which were localised over the synovial proliferative lining areas. In addition, in RA tissues, expression of the specific uPA receptor (uPAR) and of the plasminogen activator inhibitor-type 1 (PAI-1) were also increased.
CONCLUSION—Taken together, these results show an alteration of the PA/plasmin system in RA synovial tissues, resulting in increased uPA catalytic activity that may play a part in tissue destruction in RA.
相似文献
METHODS—Synovial membranes from seven normal (N) subjects, 14 osteoarthritis (OA), and 10 rheumatoid arthritis (RA) patients were analysed for plasminogen activator activity by conventional zymography and in situ zymography on tissue sections. The tissue distribution of uPA, tPA, uPA receptor (uPAR), and plasminogen activator inhibitor type-1 (PAI-1) was studied by immunohistochemistry. uPA, tPA, uPAR, and PAI-1 mRNA values and mRNA distribution were assessed by northern blot and in situ hybridisations respectively.
RESULTS—All normal and most OA synovial tissues expressed predominantly tPA catalysed proteolytic activity mainly associated to the synovial vasculature. In some OA, tPA activity was expressed together with variable amounts of uPA mediated activity. By contrast, most RA synovial tissues exhibited considerably increased uPA activity over the proliferative lining areas, while tPA activity was reduced when compared with N and OA synovial tissues. This increase in uPA activity was associated with increased levels of uPA antigen and its corresponding mRNA, which were localised over the synovial proliferative lining areas. In addition, in RA tissues, expression of the specific uPA receptor (uPAR) and of the plasminogen activator inhibitor-type 1 (PAI-1) were also increased.
CONCLUSION—Taken together, these results show an alteration of the PA/plasmin system in RA synovial tissues, resulting in increased uPA catalytic activity that may play a part in tissue destruction in RA.
相似文献
146.
Bokun Kim Takehiko Tsujimoto Rina So Xiaoguang Zhao Shun Suzuki Taeho Kim Kiyoji Tanaka 《Journal of Physical Therapy Science》2015,27(12):3787-3791
To prevent or remedy musculoskeletal conditions, the relationship between obesity and the
characteristics of muscle mass and strength need to be clarified. [Subjects and Methods] A
total of 259 Japanese males aged 30–64 years were classified into 4 groups according to
the Japanese obesity criteria. Body composition was evaluated, and handgrip strength and
knee extensor strength were measured for the upper and lower extremities, respectively.
Physical performance was evaluated with a jump test. [Results] Obesity was positively
correlated with skeletal muscle mass index, percentage of whole-body fat, and leg muscle
strength and negatively correlated with the percentage of muscle mass index, body
weight-normalized handgrip strength, and knee extensor strength, and the jump test
results. [Conclusion] Weight loss may be a better approach than increasing muscle mass and
strength to improve musculoskeletal conditions in obese adult males.Key words: Obesity, Muscle mass, Muscle strength 相似文献
147.
[Purpose] This study compared the muscle activities of the neck and upper-limb muscles
between able-bodied individuals and persons with paraplegia during wheelchair propulsion
on the ground. [Subjects and Methods] The muscle activities of the neck and upper-limb
muscles of 8 normal individuals and 8 individuals with paraplegia were analyzed during
wheelchair propulsion. The activities of the latissimus dorsi, pectoralis major,
anterior/posterior deltoids, triceps brachii, extensor carpi radialis, and
sternocleidomastoid muscles were assessed. [Results] The paraplegic group showed
significantly higher sternocleidomastoid activity than the normal group. Latissimus dorsi
activity was also higher in the paraplegia group than in the normal group, but the
difference was not significant. There were no significant differences in the other muscle
activities between groups. [Conclusion] Paraplegic patients tend to use the
sternocleidomastoid and latissimus dorsi muscles with greater degrees of activity.
Therefore, physiotherapists should not overlook the treatment of these muscles for
paraplegic patients who are long-term wheelchair users.Key words: Wheelchair propulsion, Muscle activities, Upper-limb muscle 相似文献
148.
Eva Y.F. Pang Shirley S.M. Fong Mimi M.Y. Tse Eric W.C. Tam Shamay SM Ng Billy C.L. So 《Journal of Physical Therapy Science》2015,27(6):1839-1845
[Purpose] This study investigated the intra-rater, inter-rater and test-retest
reliability of the sideways step test (SST), its correlation with other indicators of
stroke-specific impairment, and the cut-off count best discriminating subjects with stroke
from their healthy counterparts. [Subjects and Methods] Forty-three subjects with chronic
stroke and 41 healthy subjects older than 50 years participated in this study. The SST was
administered along with the Fugl-Meyer motor assessment for the lower extremities
(FMA-LE), the five-times sit to stand (5TSTS) test, the Berg Balance Scale (BBS), the
movement velocity (MVL) by the limits of stability (LOS) test, the ten-metre walk (10mW)
test, the timed “Up and Go” (TUG) test and the Activities-specific Balance Confidence
(ABC) scale. [Results] The SST showed good to excellent intra-rater, inter-rater and
test-retest reliability. The SST counts correlated with 5TSTS times, 10mW times, TUG
times, and the FMA-LE and BBS scores. SST counts of 11 for the paretic leg and 14 for the
non-paretic leg were found to distinguish the healthy adults from subjects with stroke.
[Conclusion] The sideways step test is a reliable clinical test, which correlates with the
functional strength, gait speed, and functional balance of people with chronic stroke.Key words: Balance, Stroke, Rehabilitation 相似文献
149.
Iwata M Imamura H Stambouli E Ikeda C Tamakoshi M Nagata K Makyio H Hankamer B Barber J Yoshida M Yokoyama K Iwata S 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(1):59-64
The vacuole-type ATPases (V-ATPases) exist in various intracellular compartments of eukaryotic cells to regulate physiological processes by controlling the acidic environment. The crystal structure of the subunit C of Thermus thermophilus V-ATPase, homologous to eukaryotic subunit d of V-ATPases, has been determined at 1.95-A resolution and located into the holoenzyme complex structure obtained by single particle analysis as suggested by the results of subunit cross-linking experiments. The result shows that V-ATPase is substantially longer than the related F-type ATPase, due to the insertion of subunit C between the V(1) (soluble) and the V(o) (membrane bound) domains. Subunit C, attached to the V(o) domain, seems to have a socket like function in attaching the central-stalk subunits of the V(1) domain. This architecture seems essential for the reversible association/dissociation of the V(1) and the V(o) domains, unique for V-ATPase activity regulation. 相似文献
150.
Isolation and expression of the gene for a major surface protein of Giardia lamblia. 总被引:22,自引:3,他引:22
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
F D Gillin P Hagblom J Harwood S B Aley D S Reiner M McCaffery M So D G Guiney 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(12):4463-4467
To study the interactions between the parasitic protozoan Giardia lamblia and its environment, we have cloned the gene that encodes the two major surface-labeled trophozoite protein species. Sequence analysis of this gene reveals a single open reading frame specifying a hydrophilic, cysteine-rich (11.8%) protein of 72.5-kDa molecular mass with an amino-terminal signal peptide and a postulated hydrophobic membrane-spanning anchor region near the carboxyl terminus. Most of the cysteine residues (58 of 84) are in the motif Cys-Xaa-Xaa-Cys, which is dispersed 29 times throughout the sequence. Antibodies against the recombinant protein react with the entire surface of live trophozoites, including flagella and adhesive disc. These antibodies inhibit trophozoite attachment, prevent growth, and immunoprecipitate the major approximately 66- and 85-kDa proteins from surface-labeled live trophozoites. The recombinant Escherichia coli also expresses polypeptides of approximately 66- and 85-kDa molecular mass, which are not fusion proteins. This suggests that the processing and/or conformational changes that lead to production of these two peptide species in E. coli reflect those that occur in Giardia. The abundance of cysteine residues suggests that the native proteins on the parasite surface may contain numerous disulfide bonds, which would promote resistance to intestinal fluid proteases and to the detergent activity of bile salts and would help to explain the survival of Giardia in the human small intestine. 相似文献