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   810篇
  免费   46篇
  国内免费   2篇
耳鼻咽喉   6篇
儿科学   16篇
妇产科学   5篇
基础医学   160篇
口腔科学   9篇
临床医学   32篇
内科学   158篇
皮肤病学   10篇
神经病学   76篇
特种医学   24篇
外科学   214篇
综合类   3篇
预防医学   20篇
眼科学   27篇
药学   39篇
肿瘤学   59篇
  2021年   7篇
  2019年   6篇
  2018年   11篇
  2017年   13篇
  2016年   14篇
  2015年   9篇
  2014年   14篇
  2013年   18篇
  2012年   31篇
  2011年   25篇
  2010年   26篇
  2008年   30篇
  2007年   33篇
  2006年   27篇
  2005年   31篇
  2004年   31篇
  2003年   31篇
  2002年   38篇
  2001年   20篇
  2000年   30篇
  1999年   26篇
  1998年   14篇
  1997年   9篇
  1996年   11篇
  1995年   9篇
  1994年   9篇
  1993年   7篇
  1992年   29篇
  1991年   21篇
  1990年   35篇
  1989年   27篇
  1988年   17篇
  1987年   14篇
  1986年   10篇
  1985年   22篇
  1984年   11篇
  1983年   8篇
  1982年   9篇
  1979年   18篇
  1977年   6篇
  1976年   7篇
  1975年   6篇
  1974年   8篇
  1973年   5篇
  1972年   6篇
  1971年   7篇
  1970年   6篇
  1969年   6篇
  1968年   5篇
  1967年   9篇
排序方式: 共有858条查询结果,搜索用时 31 毫秒
61.
A 68-year-old man without familial history developed ataxic gait and sensory disturbance in the lower extremities. At the age of 74, neurological examination revealed marked cerebellar ataxia of all limbs, dysarthria, sensory disturbance of glove and stocking type in the extremities, and slight neurogenic muscular atrophy. There were no mental deterioration and dysautonomia. He died of pneumonia at the age of 74. Neuropathological findings. The cerebellum was decreased in size. Microscopically, there were severe disappearance of Purkinje cells in the cerebellar vermis and hemispheres. The molecular layer, granular cell layer, and cerebellar white matter were preserved. Neurons of the inferior olivary nuclei were also spared. In the spinal cord, there was myelin pallor in the posterior column predominant in Goll's fascicule and moderate atrophy of neurons in the anterior horn. Degeneration of the posterior roots was greater than that of the anterior roots. No abnormal findings were found in the extrapyramidal system, cranial nerves, and cerebrum. We compared this case clinicopathologically with other diseases with cortical cerebellar atrophy; alcoholic cerebellar degeneration, phenytoin intoxication, neuroleptic malignant syndrome, and subacute paraneoplastic cerebellar degeneration. In conclusion, idiopathic late cerebellar cortical atrophy (LCCA) was different clinicopathologically from the other diseases. Especially, LCCA showed the characteristic topography of Purkinje cells loss sparing the molecular and granule cell layers.  相似文献   
62.
The action of ubenimex on aminopeptidase (APase) activity was studied in intact spleen cells and peritoneal macrophages from mice. Ubenimex strongly inhibited hydrolyzing activities against arginine-beta-naphtylamide (Arg-NA), Lys-NA and Pro-NA in both cells. Inhibition of hydrolysis of Leu-NA, Met-NA and Ala-NA was relatively small or not observed. When both cells were incubated in HANKS' solution, hydrolyzing activities against Arg-NA, Lys-NA and Pro-NA were released to the medium, while Leu-NA and Met-NA-hydrolyzing activities were mostly bound. In addition, the Leu-NA-hydrolyzing activity in the spleen cells was kinetically studied. The Arg-NA and Leu-NA-hydrolyzing activities in four fractions prepared from the homogenate of spleen cells were also studied kinetically. From these studies it was suggested that ubenimex inhibits aminopeptidase B and a Pro-NA-hydrolyzing enzyme more effectively than Leu-APase in intact spleen cells and peritoneal macrophages from mice.  相似文献   
63.
Chromosomes of bone marrow cells obtained from nine patients with myelodysplastic syndrome (MDS) were assessed after in vitro co-culture (48 hours culture) with recombinant human granulocyte colony-stimulating factor (rhG-CSF), recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF), or recombinant human erythropoietin. Three of the nine MDS cases showed no cytogenetic abnormalities with or without any recombinant human hematopoietic growth factors; one MDS patient with a t(3;4) did not show any change in the proportion of cells with this cytogenetic change. The remaining five cases exhibited changes in the frequency of subclones after the treatment. An increasing number of metaphase cells with less complex chromosome abnormalities was observed in two of the five cases by treatment with rhG-CSF; one of them also showed an increasing number of cells with normal karyotypes. After rhGM-CSF treatment, cells with nonclonal hyperdiploid abnormalities appeared in one MDS patient. After erythropoietin treatment, an increasing number of cells with a prototypic change was observed in one MDS patient, whereas one patient showed an increasing number of cells with an additional chromosome abnormality. These observations indicate that hematopoietic growth factors possibly modify the constitution of marrow cells with multiple chromosome abnormalities and the degree is different in each MDS patient. Furthermore, a chromosome analysis using an in vitro culture system with human recombinant hematopoietic growth factors may be able to detect metaphase cells with additional chromosome abnormalities in some MDS patients.  相似文献   
64.
Zusammenfassung Die histologische Untersuchung der Medulla oblongata eines an Tetanie plötzlich verstorbenen, 6 Monate alten Kindes zeigt ein Ödem der Meningen, das auf die Vaguswurzel übergreift und hier ein Infiltrat und leichte Nekrosen provoziert. Dabei sind schwere Veränderungen der Zellen des dorsalen Kerns und der Substantia gelatinosa des Vagus aufgetreten. Das entzündliche Ödem ist wegen der Mitbeteiligung mesodermaler Elemente, besonders der Leukocyten als akut aufzufassen, vielleicht haben wir in ihm die Ursache des plötzlichen Todes zu erblicken.Mit 2 Textabbildungen.  相似文献   
65.
Neutrophils play an important role in intestinal inflammation by interacting with intestinal epithelial cells. In this study, we evaluated neutrophil adhesion to intestinal epithelial cells using intestinal epithelial cell line HT29 stimulated with tumor necrosis factor alpha (TNF-alpha) and histamine for a short time (30 min). The TNF-alpha and histamine stimulation markedly increased neutrophil adhesion. The increased adhesion was inhibited by anti-CD11b and anti-CD18 monoclonal antibodies (mAbs), but not by anti-CD11a and anti-CD54 (ICAM-1) mAbs. It is interesting that flow cytometric analysis revealed that ICAM-1 expression on HT29 cells was not changed by TNF-alpha and histamine stimulation. Moreover, the increased adhesion was inhibited by proteinase K treatment but not cycloheximide treatment of HT29 cells. Together these observations suggest that short exposure of HT29 cells to TNF-alpha and histamine induces CD11b/CD18 (Mac-1)-dependent but CD11a/CD18 (LFA-1)-independent neutrophil adhesion to intestinal epithelial cells, and ICAM-1 is not likely to be involved in the interactions. Furthermore, epithelial cell ligand(s) for neutrophils is likely protein molecule(s) that is expressed on the cell by stimulation independent protein synthesis. However, it is also possible that neutrophil activating factor(s), which stimulates neutrophils to bind with epithelial ligands via Mac-1, is expressed by epithelial cells during stimulation.  相似文献   
66.
67.
Spinocerebellar ataxia type 2 (SCA2) is an inherited neurodegenerative disorder characterized clinically by cerebellar ataxia, slow eye movement, hyporeflexia, involuntary movement, dementia and sensory disturbance and neuropathologically by neuronal loss, mainly in the cerebellar cortex involving all three layers, the pontine nucleus, the inferior olivary nucleus, anterior horn, substantia nigra and thalamus. For making one's diagnosis, it is necessary to give careful consideration to two factors, (age at onset, disease duration). A distinctive neuropathological feature is having both simple atrophy (without degeneration) and numerical atrophy. SCA2 is associated with an expanded CAG repeat that encodes polyglutamine of a gene and a larger number of the repeat is associated with earlier onset and more severe symptoms and more severe neuronal degenerations.  相似文献   
68.
We report a case of glomerulonephritis with monoclonal immunoglobulin (Ig) A deposits as a form of monoclonal gammopathy of renal significance (MGRS) caused by monoclonal immunoglobulins without blood disorders in a 41‐year‐old woman. She developed lower leg oedema and was hospitalized because of nephrotic syndrome. Serum and urine were negative for M protein, and the free light chain κ/λ ratio was within the normal range. Renal histopathological findings included mesangial proliferation, endocapillary cell proliferation, and a double‐contour appearance of the capillary walls. Immunofluorescent staining indicated IgA and C3 deposits on the mesangium and capillary walls. Only λ chain and IgA1 deposits were noted. Fine granular sub‐endothelial deposits with no specific structure were observed under electron microscopy. The patient was diagnosed with IgA–proliferative glomerulonephritis with monoclonal immunoglobulin deposits (IgA‐PGNMID). The patient had decreased urine protein and sediment erythrocytes after she underwent two rounds of steroid pulse therapy and oral steroid therapy, but proteinuria and haematuria still remained. Four months later, the patient was administered 50 mg/day cyclosporine (CsA), and proteinuria and haematuria dramatically decreased. Only a few case reports have been published on IgA‐PGNMID. This case is rare in that the patient achieved successful treatment using a combination of steroids and CsA.  相似文献   
69.
Objectives: With the development of PCI techniques, the indications for stents have been expanding as well. On the other hand, we often encounter the situations where deploying a stent/stents by the conventional method is technically challenging. We report a novel stent delivery system using a newly developed 4Fr. straight catheter with Mother‐and‐Child method. Methods and results: We collected the data on coronary angioplasty in which we experienced the difficulty to deliver coronary stents and used 4Fr. KIWAMI ST01. The case number amounts to 32 cases over a six‐month period from October 2009 through March 2010;76:919‐–923. The angioplasty was performed for lesions in the RCA in 9 patients (28%), lesions in the LAD in 15 patients (47%), lesions in the LCX in 5 patients (16%), lesions in the saphenous vein grafts in 2 patients (6%), and lesions in the internal thoracic artery (LITA) grafts in 1 patient (3%). And the reasons for the difficult stent delivery by the conventional methods were as follows: severe calcification in 12 patients (37%), intense tortuosity in 7 patients (22%), poor backup support for guide catheter in 8 patients (25%), and trapping of the stent proximal to the target lesion in 5 patients (16%). The dislodgment of stent did not happened in all cases. Conclusions: KIWAMI® ST01 stent delivery system is feasible, safer, and effective in cases where stent delivery is difficult by the conventional method. © 2010 Wiley‐Liss, Inc.  相似文献   
70.
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