首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   141篇
  免费   8篇
  2022年   1篇
  2021年   1篇
  2019年   1篇
  2017年   5篇
  2016年   3篇
  2015年   3篇
  2014年   2篇
  2013年   6篇
  2012年   6篇
  2011年   6篇
  2010年   5篇
  2009年   3篇
  2008年   6篇
  2007年   3篇
  2006年   8篇
  2005年   3篇
  2004年   8篇
  2003年   5篇
  2002年   9篇
  2001年   7篇
  2000年   8篇
  1999年   1篇
  1998年   1篇
  1997年   1篇
  1994年   2篇
  1993年   1篇
  1992年   2篇
  1991年   2篇
  1990年   2篇
  1989年   2篇
  1988年   5篇
  1987年   3篇
  1985年   4篇
  1984年   1篇
  1983年   1篇
  1980年   1篇
  1979年   4篇
  1975年   1篇
  1966年   2篇
  1965年   1篇
  1964年   2篇
  1963年   5篇
  1961年   4篇
  1959年   2篇
排序方式: 共有149条查询结果,搜索用时 31 毫秒
121.
Sleep and Biological Rhythms - This study examined the long-term effects of a brief behavioral intervention for sleep improvement. The program was designed as a complete self-help approach by...  相似文献   
122.
Sleep and Biological Rhythms - This study examined the relation between the bedtime of 4-month-old infants and their daily weight gain, using health check-up data and a questionnaire. The infants,...  相似文献   
123.
Three partial S-RNase genes, MSRN-1, MSRN-2, and MSRN-3, in the Japanese apricot (Prunus mume Sieb. et Zucc.) were isolated from the three cultivars Nankou, Gyokuei, and Kairyouuchidaume, respectively. The structural characteristics revealed that S-RNase genes from the Japanese apricot were in the T2/SRNase-type S-RNase family with five conserved regions (C1, C2, C3, RC4, and C5) and one variable region (RHV) as reported in the other rosaceous plants. In the phylogenetic tree of T2/S SRNase-type RNases, three S-RNase genes of the Japanese apricot did not form a species-specific subgroup but the Prunus subfamily did. At least seven S-allelic genes were present in the Japanese apricot, and S-genotypes of six representative cultivars, including Nankou, Gyokuei, Kairyouuchidaume, Baigou, Kagajizou, and Oushuku were first established in this study as S 1 S 7, S 2 S 6, S 3 S 4, S 3 S 6, S 3 S 6 and S 1 S 5, respectively. An extended elucidation of the S-genotype would contribute to a more efficient breeding program of the Japanese apricot. Received: 5 September 2000 / Revision accepted: 22 December 2000  相似文献   
124.
We studied the expression pattern of Na, K-ATPase beta 1 subunit in human normal stomachs and in gastric adenocarcinomas by using anti-Na, K-ATPase beta 1 subunit-specific monoclonal antibody. Tissue samples were processed in formalin solution or in a cold acetic acid-ethanol solution, routinely processed, embedded in paraffin, and an immunoperoxidase method for Na, K-ATPase beta 1 subunit was performed. After antigen retrieval using a steamer in citrate buffer (pH 6.0), tissue sections initially fixed in cold acetic acid-ethanol showed intense immunoreactivity with the antibody at the lateral or basolateral cytoplasmic membrane of normal gastric epithelial cells, at the cytoplasmic membrane of gastric carcinoma cells according to the level of differentiation, and at the cytoplasmic membrane and in the cytoplasm of Schwann cells and neurons in the mesenteric plexus of the gastric wall. Acetic acid-ethanol and paraffin embedding is a useful method for the investigation of the immunohistochemical localization of Na, K-ATPase in normal and diseased tissues.  相似文献   
125.
126.
The synthesis and structure-activity relationships of 6-carboxy-2-isopropylamino-5,7-diarylcyclopenteno[1,2-b]pyridine class of ET(A) receptor selective antagonists were described. These derivatives were prepared from the optically active key intermediates (3, 4, 10, and 13). Optimization of the substituent at the 2-position of the bottom 4-methoxyphenyl ring of the lead compound 1 led to identification of 2-hydroxy-1-methylethoxy (2g and h), hydroxyalkyl (2i, m, and p), 3-methoxy-2-methylpropyl (2t and u), N-acetyl-N-methylaminomethyl (2v), and 2-(dimethylcarbamoyl)propyl (2w) derivatives that showed greater than 1000-fold selectivity for the ET(A) receptor over the ET(B) receptor with excellent binding affinity (IC(50)<0.10 nM). Further screening of these compounds by assessing the plasma exposures at 1 h, 4 h, and 8 h after oral administration (3 or 10 mg/kg) in rats led to identification of the hydroxymethyl (2i) and 3-methoxy-2-methylpropyl (2u) derivatives exhibiting good oral bioavailability in rats.  相似文献   
127.
128.
Activation of cardiac STAT3 by IL-6 cytokine family contributes to cardioprotection. Previously, we demonstrated that IL-11, an IL-6 cytokine family, has the therapeutic potential to prevent adverse cardiac remodeling after myocardial infarction; however, it remains to be elucidated whether IL-11 exhibits postconditioning effects. To address the possibility that IL-11 treatment improves clinical outcome of recanalization therapy against acute myocardial infarction, we examined its postconditioning effects on ischemia/reperfusion (I/R) injury. C57BL/6 mice were exposed to ischemia (30 min) and reperfusion (24 h), and IL-11 was intravenously administered at the start of reperfusion. I/R injury mediated the activation of STAT3, which was enhanced by IL-11 administration. IL-11 treatment reduced I/R injury, analyzed by triphenyl tetrazolium chloride staining [PBS, 46.7 ± 14.4%; IL-11 (20 μg/kg), 28.6 ± 7.5% in the ratio of infarct to risk area]. Moreover, echocardiographic and hemodynamic analyses clarified that IL-11 treatment preserved cardiac function after I/R. Terminal deoxynucleotide transferase-mediated dUTP nick-end labeling staining revealed that IL-11 reduced the frequency of apoptotic cardiomyocytes after I/R. Interestingly, IL-11 reduced superoxide production assessed by in situ dihydroethidium fluorescence analysis, accompanied by the increased expression of metallothionein 1 and 2, reactive oxygen species (ROS) scavengers. Importantly, with the use of cardiac-specific STAT3 conditional knockout (STAT3 CKO) mice, it was revealed that cardiac-specific ablation of STAT3 abrogated IL-11-mediated attenuation of I/R injury. Finally, IL-11 failed to suppress the ROS production after I/R in STAT3 CKO mice. IL-11 administration exhibits the postconditioning effects through cardiac STAT3 activation, suggesting that IL-11 has the clinical therapeutic potential to prevent I/R injury in heart.  相似文献   
129.
Narita  Ayu  Nakahama  Naoyuki  Izuno  Ayako  Hayama  Kayo  Komaki  Yoshiteru  Tanaka  Takefumi  Murata  Jin  Isagi  Yuji 《Conservation Genetics》2021,22(5):717-727

Crepidiastrum grandicollum is a critically endangered insular endemic herb found only on two oceanic islands of the Bonin Islands in Japan, namely Chichijima Island and Anijima Island. It is explicitly threatened by herbivory pressure from introduced animals. In 2009, a conservation program for C. grandicollum was begun to ensure its future persistence. To provide further information for conservation planning, we investigated the genetic diversity of C. grandicollum using 13 novel microsatellite markers in 55 individuals from four wild populations and an ex situ living collection. Two closely related woody species were also included for interspecific comparison: seven individuals of Crepidiastrum ameristophyllum and 13 of Crepidiastrum linguifolium. The 13 markers were applicable to all three species and identified 129 alleles in total. We found a clear genetic differentiation between C. grandicollum from Anijima Island and Chichijima Island. Crepidiastrum grandicollum also had low expected heterozygosity and allelic richness in populations compared to the two closely related species. Reconstructed divergence history suggested that differentiation between the islands had occurred several thousand generations ago. We suggest separate conservation units for C. grandicollum on Anijima Island and Chichijima Island given the clear (and putatively historical) genetic differentiation, which may result in speciation in the future.

  相似文献   
130.
Highly pathogenic avian influenza (HPAI) viruses of the H5N1 subtype often cause severe pneumonia and multiple organ failure in humans, with reported case fatality rates of more than 60%. To develop a clinical antibody therapy, we generated a human-mouse chimeric monoclonal antibody (MAb) ch61 that showed strong neutralizing activity against H5N1 HPAI viruses isolated from humans and evaluated its protective potential in mouse and nonhuman primate models of H5N1 HPAI virus infections. Passive immunization with MAb ch61 one day before or after challenge with a lethal dose of the virus completely protected mice, and partial protection was achieved when mice were treated 3 days after the challenge. In a cynomolgus macaque model, reduced viral loads and partial protection against lethal infection were observed in macaques treated with MAb ch61 intravenously one and three days after challenge. Protective effects were also noted in macaques under immunosuppression. Though mutant viruses escaping from neutralization by MAb ch61 were recovered from macaques treated with this MAb alone, combined treatment with MAb ch61 and peramivir reduced the emergence of escape mutants. Our results indicate that antibody therapy might be beneficial in reducing viral loads and delaying disease progression during H5N1 HPAI virus infection in clinical cases and combined treatment with other antiviral compounds should improve the protective effects of antibody therapy against H5N1 HPAI virus infection.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号