全文获取类型
收费全文 | 159篇 |
免费 | 8篇 |
国内免费 | 7篇 |
专业分类
儿科学 | 12篇 |
妇产科学 | 2篇 |
基础医学 | 10篇 |
口腔科学 | 2篇 |
临床医学 | 26篇 |
内科学 | 46篇 |
皮肤病学 | 1篇 |
神经病学 | 2篇 |
特种医学 | 52篇 |
外科学 | 5篇 |
综合类 | 3篇 |
预防医学 | 7篇 |
药学 | 4篇 |
肿瘤学 | 2篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 3篇 |
2014年 | 1篇 |
2013年 | 5篇 |
2011年 | 1篇 |
2010年 | 3篇 |
2009年 | 8篇 |
2008年 | 1篇 |
2007年 | 8篇 |
2006年 | 5篇 |
2005年 | 1篇 |
2004年 | 3篇 |
2003年 | 3篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 9篇 |
1997年 | 4篇 |
1996年 | 8篇 |
1995年 | 4篇 |
1994年 | 15篇 |
1993年 | 11篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 7篇 |
1988年 | 9篇 |
1987年 | 11篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 7篇 |
1980年 | 4篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1975年 | 3篇 |
排序方式: 共有174条查询结果,搜索用时 0 毫秒
61.
62.
63.
64.
Myelomonocytic antigen positive multiple myeloma 总被引:6,自引:0,他引:6
In a four year span, between 1983 and 1987, 215 bone marrow and cell culture samples from 125 myeloma patients were immunotyped and coexpression of myelomonocytic and plasma cell antigens occurred in 16 (13%). We employed both immunohistochemical and flow cytometry methods including coplots and double labelling. Three types of myeloma cases were found: (1) those with isolated myeloid antigen coexpression, usually Leu M1 or esterase (BE, CE) positive (11 cases); (2) those with multiple myeloid antigens (Leu M1, M3, M5, MY7, BE, CE) (four cases); and (3) one case beginning as 1 and ending as 2. Isolated myeloid antigen expression was generally associated with typical features of myeloma with survival close to the anticipated median (33 months), while multiple myeloid antigen expression was associated with more aggressive disease and shorter survival duration (median survival 16 months). The latter subgroup also had other poor prognostic factors including high labelling index and common acute lymphoblastic leukemia antigen (CALLA) positivity. Other features found overall were frequent abnormal karyotypes (seven of 12 abnormal) and coexpressed IgA (eight of 16); all IgA+ cases also coexpressed Leu M1. We conclude that there is an unusual and unexpected predilection for coexpression of myelomonocytic antigens in myeloma cells. The reasons are not immediately obvious. Whether the coexpression indicates that myeloma cells truly have latent multilineage potential or just aberrantly coexpress other hematopoietic antigens as a manifestation of malignancy remains to be explained. However, a cell line established from the bone marrow of one patient is a valuable scientific tool allowing detailed analysis of these questions. 相似文献
65.
Routine fetal genitourinary tract screening 总被引:7,自引:0,他引:7
Arger PH; Coleman BG; Mintz MC; Snyder HP; Camardese T; Arenson RL; Gabbe SG; Aquino L 《Radiology》1985,156(2):485-489
To evaluate routine fetal genitourinary tract obstetrical ultrasound screening, and to determine what size renal pelvis is indicative of significant renal disease, we reviewed 4,832 examinations, which had been performed over 2 years, of 3,530 consecutive obstetrical patients. Any fetus that had a renal pelvis greater than 5 mm or a definable cystic area was identified for follow-up. The fetuses of 39 patients (1.1%) who underwent 112 examinations fulfilled these criteria and constitute the basis of this report. A variety of examination criteria were recorded and analyzed in relationship to the follow-up, which ranged from 2-3 days to 21 months. The fetuses of the 39 patients were grouped into three categories: those with renal pelves between 5 and 9 mm in size; those with renal pelves larger than 10 mm; and those with cystic abnormalities. Those with renal pelves larger than 10 mm had either an obstructing lesion or exceptional extrarenal pelves. The clinical and pathologic aspects of these three groups are detailed, discussed, and analyzed. Criteria for significant fetal renal hydronephrosis and aspects of a loculated appearance are given. 相似文献
66.
Erythroid and nonerythroid spectrins 总被引:8,自引:0,他引:8
Recent developments have contributed important information to understanding the role of spectrins in the RBC membrane skeleton and nonerythroid cells. Many questions can now be framed, informed by structural knowledge of various spectrin subunit types and alternatively spliced variants, that previously could not have been addressed. Their solution in the coming years will likely lead to further advances with direct relevance to biology and medicine. 相似文献
67.
JM Danger MC Tonon BG Jenks S. Saint-Pierre JC Martel A. Fasolo B. Breton R. Quirion G. Pelletier and H. Vaudry 《Fundamental & clinical pharmacology》1990,4(3):307-340
Neuropeptide Y (NPY) is a 36-amino acid peptide first isolated and characterized from porcine brain extracts. A number of immunocytochemical investigations have been conducted to determine the localization of NPY-containing neurons in various animal species including both vertebrates and invertebrates. These studies have established the widespread distribution of NPY in the brain and in sympathetic neurons. In the rat brain, a high density of immunoreactive cell bodies and fibers is observed in the cortex, caudate putamen and hippocampus. In the diencephalon, NPY-containing perikarya are mainly located in the arcuate nucleus of the hypothalamus; numerous fibers innervate the paraventricular and suprachiasmatic nuclei of the hypothalamus, as well as the paraventricular nucleus of the thalamus and the periaqueductal gray. At the electron microscope level, using the pre- and post-embedding immunoperoxidase techniques, NPY-like immunoreactivity has been observed in neuronal cell body dendrites and axonal processes. In nerve terminals of the hypothalamus, the product of the immunoreaction is associated with large dense core vesicles. In lower vertebrates, including amphibians and fish, neurons originating from the diencephalic (or telencephalic) region innervate the intermediate lobe of the pituitary where a dense network of immunoreactive fibers has been detected. At the ultrastructural level, positive endings have been observed in direct contact with pituitary melanotrophs of frog and dogfish. These anatomical data suggest that NPY can act both as a neurotransmitter (or neuromodulator) and as a hypophysiotropic neurohormone. In the rat a few NPY-containing fibers are found in the internal zone of the median eminence and high concentrations of NPY-like immunoreactivity are detected in the hypothalamo-hypophyseal portal blood, suggesting that NPY may affect anterior pituitary hormone secretion. Intrajugular injection of NPY causes a marked inhibition of LH release but does not significantly affect other pituitary hormones. Passive immunoneutralization of endogenous NPY by specific NPY antibodies induces stimulation of LH release in female rats, suggesting that NPY could affect LH secretion at the pituitary level. However, NPY has no effect on LH release from cultured pituitary cells or hemipituitaries. In addition, autoradiographic studies show that sites for 125I-labeled Bolton-Hunter NPY or 125I-labeled PYY (2 specific ligands of NPY receptors) are not present in the adenohypophysis, while moderate concentrations of these binding sites are found in the neural lobe of the pituitary. It thus appears that the inhibitory effect of NPY on LH secretion must be mediated at the hypothalamic level.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
68.
Renal allografts: prospective analysis of Doppler sonography 总被引:2,自引:0,他引:2
Allen KS; Jorkasky DK; Arger PH; Velchik MG; Grumbach K; Coleman BG; Mintz MC; Betsch SE; Perloff LJ 《Radiology》1988,169(2):371-376
Fifty-six consecutively transplanted renal allografts were prospectively evaluated with serial Doppler sonographic examinations. Thirty-eight episodes of transplant rejection in 32 patients (63% proved pathologically) and 24 episodes of acute tubular necrosis (ATN) in 24 patients were encountered. The Doppler spectral waveform was characterized by means of the pulsatility index (PI), systolic/diastolic ratio (SDR), diastolic/systolic ratio (SDR), diastolic/systolic ratio (DSR), and resistive index (RI). Accuracy was optimized with use of top normal values as follows: PI = 1.8, SDR = 4.0, DSR = 0.25, RI = 0.75. There were no significant differences in the indices for those patients undergoing rejection versus those with ATN. The sensitivity for predicting transplant rejection was adversely affected by the history of either ATN or a previous rejection episode in the same allograft. Comparison with concurrent radionuclide examinations revealed similar sensitivities for rejection with scintigraphy and sonography. Differentiation of ATN from rejection was more reliable with scintigraphy than with sonography. 相似文献
69.
70.
许旺细胞增殖和分化过程中的信号通路 总被引:2,自引:0,他引:2
目的:探讨许旺细胞增殖和分化过程中细胞内各种信号通路及其关联性。资料来源:应用计算机检索Medline 1994-01/2006-12和Embase 1994-01/2006-12期间的有关许旺细胞增殖和分化相关的信号通路的文献,检索词“Schwann cell;proliferation;differentiation;signal transduction”,并限定文章语言种类为英文。资料选择:选取与许旺细胞增殖和分化相关的有关信号通路的文献,进行初审,删除与信号通路不相关的研究,然后查找余下的文献全文。质量评价主要考察资料的真实性,调查设计是否严密,实施过程是否严格,统计学处理是否合理。资料提炼:共检索54篇与许旺细胞增殖和分化相关的有关信号通路的文献研究,纳入30篇文章。14篇有关许旺细胞增殖,12篇许旺细胞分化,4篇是其他的相关信号通路。资料综合:许旺细胞的分化和基因表达是通过各种细胞外信号来调控的,多种信号通路相互联系。来自于受体酪氨酸激酶,丝裂原活化蛋白激酶,磷酯酰肌醇-3激酶通路的信号在许旺细胞增殖和分化过程中都有很重要的作用,它们之间的平衡决定了细胞最后的功能。而细胞内膜受体G蛋白偶联的环磷腺苷浓度促进了细胞的各种功能,也参与调节了其他信号通路。结论:许旺细胞增殖和分化过程是多种信号通路相互联系完成的,阐明不同信号通路之间的关系以及它们的交互作用对于揭示许旺细胞的生物学功能有重要的意义。 相似文献