全文获取类型
收费全文 | 355篇 |
免费 | 48篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 11篇 |
妇产科学 | 11篇 |
基础医学 | 60篇 |
口腔科学 | 10篇 |
临床医学 | 48篇 |
内科学 | 79篇 |
皮肤病学 | 2篇 |
神经病学 | 21篇 |
特种医学 | 2篇 |
外科学 | 58篇 |
综合类 | 7篇 |
预防医学 | 19篇 |
眼科学 | 32篇 |
药学 | 24篇 |
中国医学 | 3篇 |
肿瘤学 | 19篇 |
出版年
2023年 | 2篇 |
2022年 | 15篇 |
2021年 | 31篇 |
2020年 | 8篇 |
2019年 | 22篇 |
2018年 | 26篇 |
2017年 | 16篇 |
2016年 | 21篇 |
2015年 | 15篇 |
2014年 | 20篇 |
2013年 | 21篇 |
2012年 | 41篇 |
2011年 | 50篇 |
2010年 | 8篇 |
2009年 | 14篇 |
2008年 | 27篇 |
2007年 | 13篇 |
2006年 | 14篇 |
2005年 | 10篇 |
2004年 | 5篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 4篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1987年 | 1篇 |
1979年 | 1篇 |
1972年 | 2篇 |
1970年 | 1篇 |
排序方式: 共有409条查询结果,搜索用时 15 毫秒
1.
2.
NH4+ secretion in inner medullary collecting duct in potassium deprivation: Role of colonic H+-K+-ATPase. BACKGROUND: In K+ deprivation (KD), gastric (g) H+-K+-ATPase (HKA) is suppressed, whereas colonic (c) HKA is induced in the terminal inner medullary collecting duct (IMCD). We hypothesized that in KD, cHKA is induced and can mediate the secretion of NH4+. METHODS: Rats were sacrificed after 2, 3, 6, or 14 days on regular (NML) or K+-free (KD) diet. mRNA expression of HKA isoforms in terminal inner medulla was examined and correlated with NH4+ secretion in perfused IMCD in vitro. RESULTS: Urinary NH4+ excretion increased after K+-free diet for six days. In terminal inner medulla, cHKA expression was strongly induced, whereas gHKA expression was decreased. NH4+ secretion increased by 62% in KD (JtNH4+ 0.57 vs. 0.92 pmol/min/mm tubule length, P < 0.001). Ouabain (1 mM) in perfusate inhibited NH4+ secretion in KD by 45% (P < 0.002) but not in NML. At luminal pH 7.7, which inhibits NH3 diffusion, NH4+ secretion in IMCD was 140% higher in KD (0.36 vs. 0.15, P < 0.03) and was sensitive to ouabain. ROMK-1 mRNA expression was induced in parallel with cHKA in inner medulla. CONCLUSIONS: These data suggest that in KD, cHKA replaces gHKA and mediates enhanced secretion of NH4+ (and H+) into the lumen facilitated by K+ recycling through ROMK-1. 相似文献
3.
BACKGROUND: Studies have shown that glucocorticoids enhance HCO3- reabsorption in proximal tubules. Functional and molecular studies indicate that HCO3- reabsorption in proximal tubules is mediated via luminal H(+)-ATPase and Na+/H+ exchanger (NHE-3), and basolateral Na+:HCO3- cotransporter (NBC) acting in series. The purpose of these experiments was to examine the effect of adrenal steroids on NBC-1 and NHE-3 expression and activity in rat renal proximal tubules. METHODS: Rats were injected subcutaneously with dexamethasone (100 mu/day) or deoxycorticosterone acetate (30 mg/kg), potent glucocorticoid, or mineralocorticoid analogues, respectively. Animals were sacrificed after two or four days, and NBC-1 and NHE-3 mRNA expression and activities were measured in cortex and proximal tubules. RESULTS: Northern hybridizations indicated that cortical NBC-1 mRNA expression increased by approximately 92% in rats treated with dexamethasone for four days (N = 6, P < 0.03) but not two days. NHE-3 mRNA expression remained unchanged. NBC and NHE-3 activities were measured as the Na-dependent pHi recovery from an acid load in the presence or absence of HCO3-, respectively, and appropriate inhibitors in proximal tubule suspensions loaded with BCECF. NBC activity increased by approximately 80% in rats treated with dexamethasone for four days (P < 0.01, N = 5) but not two days. NHE-3 activity increased by 34 and 42% in rats treated with dexamethasone for two and four days, respectively (P < 0.05 and P < 0.02 for each group vs. control). Treatment with deoxycorticosterone acetate did not alter NBC-1 expression. CONCLUSION: Glucocorticoids at pharmacologic concentrations enhance the mRNA expression and functional activity of renal proximal tubule NBC-1. Enhanced NBC and NHE-3 activities could result in increased HCO3- reabsorption in proximal tubule and could contribute to the maintenance of metabolic alkalosis in pathophysiologic states associated with increased glucocorticoid production. 相似文献
4.
Seyed Ali Tabatabaei Mohammad Soleimani Bahram Bohrani Ali Banafsheafshan Shahin Faghihi Houshang Faghihi 《国际眼科》2019,12(3):523-525
Letter to the Editor 相似文献
5.
MicroRNAs (miRs) are potential therapeutic targets in glioblastoma multiforme (GBM), but the difficulties associated with their delivery to tumor target cells have hampered their widespread use. Mesenchymal stem cells (MSCs) can migrate to the sites of cancers, including GBM and exert anti-tumor effects. In this study, it is shown that Wharton’s jelly-MSCs (WJ-MSCs) have the ability to deliver exogenous miRs to GBM cells and the functional impact of this delivery is characterized. It is found that the labeled miR-124, as an example for miR of interest, can be successfully delivered with WJ-MSCs to U87 GBM cells via dependent or exosome-independent processes. It is demonstrated that the delivered exogenous miR-124 significantly decreases the luciferase activity of the target gene CDK6. In addition, the delivered miR-124 enhances the chemosensitivity of GBM cells to temozolomide and decreases the migration of GBM cells. These results suggest that the use of exogenous miRNA delivery with the derived exosomes from WJ-MSCs may provide a novel approach for miRNA replacement therapy in GBM cancers. 相似文献
6.
7.
8.
9.
Soleimani A Salarifar M Kasaian SE Sadeghian S Nejatian M Abbasi A 《Asian cardiovascular & thoracic annals》2008,16(3):202-207
To evaluate the effects of a cardiac rehabilitation program on heart rate recovery after percutaneous transluminal coronary angioplasty, a historical cohort study was performed on 436 patients of whom 285 were grouped on completion of 5, 10, or 24 training sessions. All 3 groups showed significant improvements in heart rate recovery, peak heart rate during treadmill testing, and end-training heart rate, from baseline to follow-up. Heart rate recovery on follow-up correlated significantly with the number of completed exercise sessions. The number of sessions, baseline ejection fraction, and age were independent predictors of mean post-training heart rate recovery. The cardiac rehabilitation program had a significant effect on peak heart rate and heart rate recovery, regardless of the underlying characteristics of the patients. 相似文献
10.
Mojtaba Jafari Hossein Rafiei Asra Nassehi Farzaneh Soleimani Mansuor Arab Mohammad Reza Noormohammadi 《Indian Journal of Palliative Care》2015,21(2):192-197