全文获取类型
收费全文 | 6058篇 |
免费 | 428篇 |
国内免费 | 99篇 |
专业分类
耳鼻咽喉 | 72篇 |
儿科学 | 199篇 |
妇产科学 | 85篇 |
基础医学 | 977篇 |
口腔科学 | 85篇 |
临床医学 | 587篇 |
内科学 | 1253篇 |
皮肤病学 | 128篇 |
神经病学 | 568篇 |
特种医学 | 465篇 |
外科学 | 735篇 |
综合类 | 86篇 |
现状与发展 | 2篇 |
预防医学 | 290篇 |
眼科学 | 122篇 |
药学 | 465篇 |
中国医学 | 45篇 |
肿瘤学 | 421篇 |
出版年
2023年 | 52篇 |
2022年 | 154篇 |
2021年 | 258篇 |
2020年 | 124篇 |
2019年 | 179篇 |
2018年 | 170篇 |
2017年 | 139篇 |
2016年 | 179篇 |
2015年 | 245篇 |
2014年 | 301篇 |
2013年 | 345篇 |
2012年 | 486篇 |
2011年 | 465篇 |
2010年 | 263篇 |
2009年 | 219篇 |
2008年 | 327篇 |
2007年 | 309篇 |
2006年 | 313篇 |
2005年 | 217篇 |
2004年 | 222篇 |
2003年 | 149篇 |
2002年 | 162篇 |
2001年 | 117篇 |
2000年 | 106篇 |
1999年 | 94篇 |
1998年 | 66篇 |
1997年 | 67篇 |
1996年 | 49篇 |
1995年 | 46篇 |
1994年 | 46篇 |
1993年 | 36篇 |
1992年 | 42篇 |
1991年 | 54篇 |
1990年 | 51篇 |
1989年 | 73篇 |
1988年 | 34篇 |
1987年 | 47篇 |
1986年 | 42篇 |
1985年 | 42篇 |
1984年 | 28篇 |
1983年 | 29篇 |
1982年 | 16篇 |
1981年 | 17篇 |
1980年 | 13篇 |
1979年 | 22篇 |
1976年 | 13篇 |
1972年 | 15篇 |
1971年 | 18篇 |
1970年 | 14篇 |
1969年 | 13篇 |
排序方式: 共有6585条查询结果,搜索用时 15 毫秒
101.
[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
102.
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
103.
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
104.
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
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
105.
Park YJ Lee YJ Kim SH Joung DS Kim BJ So I Park do J Cho BY 《Molecular and cellular endocrinology》2008,285(1-2):19-25
Ghrelin regulates cell proliferation through the growth hormone secretagogue receptor (GHS-R). We confirmed the expression of GHS-R in FRTL-5 thyroid cells and investigated the effects of ghrelin in thyrocytes using FRTL-5 cells. Ghrelin increased intracellular calcium levels but not intracellular cyclic AMP levels. Ghrelin activated Erk within 2min, then activated Akt and STAT3. Erk phosphorylation was inhibited by the calcium inhibitor cyclopiazonic acid (CPA). Ghrelin alone did not stimulate FRTL-5 cell proliferation but enhanced the effects of thyroid stimulating hormone (TSH). Pretreatment with TSH potentiates the growth effects of ghrelin in thyroid cells, and p66Shc, a growth factor receptor adaptor protein, might mediate these synergistic effects. Ghrelin phosphorylated TSH-induced p66Shc, which was inhibited by CPA. Ghrelin did not affect the proliferation of ARO cells, which showed no increased expression of p66Shc after TSH treatment. Thus, ghrelin-induced intracellular calcium signaling enhanced the TSH-induced proliferation of thyrocytes, possibly mediated by the p66Shc pathway. 相似文献
106.
Sorin V. Fedeles Jae-Seon So Amol Shrikhande Seung Hun Lee Anna-Rachel Gallagher Christina E. Barkauskas Stefan Somlo Ann-Hwee Lee 《The Journal of clinical investigation》2015,125(5):1955-1967
The HSP40 cochaperone SEC63 is associated with the SEC61 translocon complex in the ER. Mutations in the gene encoding SEC63 cause polycystic liver disease in humans; however, it is not clear how altered SEC63 influences disease manifestations. In mice, loss of SEC63 induces cyst formation both in liver and kidney as the result of reduced polycystin-1 (PC1). Here we report that inactivation of SEC63 induces an unfolded protein response (UPR) pathway that is protective against cyst formation. Specifically, using murine genetic models, we determined that SEC63 deficiency selectively activates the IRE1α-XBP1 branch of UPR and that SEC63 exists in a complex with PC1. Concomitant inactivation of both SEC63 and XBP1 exacerbated the polycystic kidney phenotype in mice by markedly suppressing cleavage at the G protein–coupled receptor proteolysis site (GPS) in PC1. Enforced expression of spliced XBP1 (XBP1s) enhanced GPS cleavage of PC1 in SEC63-deficient cells, and XBP1 overexpression in vivo ameliorated cystic disease in a murine model with reduced PC1 function that is unrelated to SEC63 inactivation. Collectively, the findings show that SEC63 function regulates IRE1α/XBP1 activation, SEC63 and XBP1 are required for GPS cleavage and maturation of PC1, and activation of XBP1 can protect against polycystic disease in the setting of impaired biogenesis of PC1. 相似文献
107.
108.
109.
110.
Junya Yamamoto Daigo Nakazawa Saori Nishio Yasunobu Ishikawa Minoru Makita Yoshihiro Kusunoki So Nagai Yuichiro Fujieda Masahiko Takahata Kanji Yamada Tsuyoshi Yamamura Akihiko Yotsukura Masanobu Saito Masaru Shimazaki Tatsuya Atsumi 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2020,24(2):146-153
Adynamic bone disease in HD patients is characterized by skeletal resistance to parathyroid hormone (PTH) or suppression of PTH release, leading to a downregulated bone turnover and bone fracture. Hence, we examined the efficacy of weekly teriparatide for HD patients with low PTH indicating adynamic bone disease without a history of parathyroidectomy. Fifteen HD patients with low PTH were recruited in this prospective observational study. Of them, 10 received teriparatide for 12 months and five nontreated patients were enrolled as control. Primary outcomes were defined as the changes in bone mineral density and bone turnover markers. Bone mineral density at the lumbar spine increased by 3.7% and 2.5% at 6 and 12 months, respectively, and bone formation markers increased, while bone resorption markers did not change in the teriparatide group. At 12 months after teriparatide administration, endogenous PTH was secreted followed by the recovery of low bone turnover. 40% of patients in the teriparatide group dropped out due to adverse events and the most common adverse event was transient hypotension. This study suggests that weekly teriparatide for HD patients with low PTH in the absence of parathyroidectomy accelerates bone formation and bone turnover, leading to increased trabecular bone mass and secretion of endogenous PTH. 相似文献