全文获取类型
收费全文 | 11506篇 |
免费 | 580篇 |
国内免费 | 74篇 |
专业分类
耳鼻咽喉 | 142篇 |
儿科学 | 187篇 |
妇产科学 | 140篇 |
基础医学 | 1359篇 |
口腔科学 | 433篇 |
临床医学 | 779篇 |
内科学 | 3173篇 |
皮肤病学 | 97篇 |
神经病学 | 727篇 |
特种医学 | 303篇 |
外科学 | 2044篇 |
综合类 | 70篇 |
一般理论 | 1篇 |
预防医学 | 289篇 |
眼科学 | 276篇 |
药学 | 942篇 |
中国医学 | 25篇 |
肿瘤学 | 1173篇 |
出版年
2023年 | 125篇 |
2022年 | 229篇 |
2021年 | 417篇 |
2020年 | 204篇 |
2019年 | 243篇 |
2018年 | 298篇 |
2017年 | 223篇 |
2016年 | 261篇 |
2015年 | 233篇 |
2014年 | 289篇 |
2013年 | 382篇 |
2012年 | 636篇 |
2011年 | 657篇 |
2010年 | 338篇 |
2009年 | 255篇 |
2008年 | 463篇 |
2007年 | 531篇 |
2006年 | 464篇 |
2005年 | 476篇 |
2004年 | 433篇 |
2003年 | 410篇 |
2002年 | 442篇 |
2001年 | 264篇 |
2000年 | 291篇 |
1999年 | 282篇 |
1998年 | 118篇 |
1997年 | 97篇 |
1996年 | 98篇 |
1995年 | 106篇 |
1994年 | 77篇 |
1993年 | 67篇 |
1992年 | 241篇 |
1991年 | 193篇 |
1990年 | 185篇 |
1989年 | 217篇 |
1988年 | 179篇 |
1987年 | 173篇 |
1986年 | 171篇 |
1985年 | 159篇 |
1984年 | 121篇 |
1983年 | 109篇 |
1982年 | 70篇 |
1981年 | 53篇 |
1979年 | 80篇 |
1978年 | 68篇 |
1977年 | 60篇 |
1976年 | 68篇 |
1974年 | 73篇 |
1972年 | 54篇 |
1969年 | 66篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
G Saigo R Ryo Y Nakaya N Yamaguchi R Ryo K Saigo K Ueda 《Rinsho byori. The Japanese journal of clinical pathology》1986,34(12):1417-1421
82.
Shinichiro Ushigome Toshifumi Takakuwa Masayuki Takagi Hirotaka Koizumi Masamichi Morikubo 《Pathology international》1986,36(7):963-971
Cases of proliferative myositis and fasciitis were studied immunohisto-chemically and ultra structurally for further understanding of the nature of ganglion cell-like giant cells. Blood coagulation factor XIIIa, fibronectin, myoglobin, myosin, CPK MM, and alpha-1-antichymotrypsin were detected in three cases of proliferative myositis and two cases of proliferative fasciitis by the avid in-biotin-peroxidase complex method. Factor XIIIa (a fibrin-stabilizing factor) and flbronectin were strongly positive in the giant cells, but not in striated muscle fibers. A small quantity of myosin was demonstrated in the giant cells, but myoglobin and CPK MM were never demonstrated in these cells. No alpha-1-antichymotrypsin was demonstrated in the giant cells. One case of proliferative myositis showed ultrastructural features suggestive of fibroblast rather than muscle cell or histiocytic origin. Strongly positive factor XIIIa in the giant cells is suggestive of the fact that they are active fibroblasts. 相似文献
83.
The alar plate of the prosencephalon differentiates into a tectum-like structure when transplanted into the mesencephalon around the 10-somite stage. Here, we report on the projection pattern of the retinal ganglion cells to the transplants. Optic nerve fibers were labeled with horseradish peroxidase (HRP) and 3H-proline, and the innervation of the optic nerve fibers to the chimeric tectum was analyzed by HRP histochemistry on whole-mounted specimens, by autoradiography and by electron microscopy on embryonic day 16. In the chimeric tectum, the transplant was distinguished from the host by difference in nuclear structure between the quail and the chick cells. It was shown that the transplant had the laminar pattern of the optic tectum when the transplant was integrated into the host mesencephalon. The whole-mount HRP histochemistry showed that the optic nerve fibers extend to the transplants. Autoradiography showed that the distribution pattern of silver grains was similar in both the host and the transplant. These results may indicate that the optic nerve fibers turn to the transplant and terminate on the transplant. Electron microscopy further confirmed that optic nerve fibers ended by making synaptic contacts with the dendrites in the transplant region of the tectum. These results indicate that the transplant with the laminar pattern of the optic tectum is a true tectum receiving input from the eye. 相似文献
84.
85.
Herpes simplex virus type 1 restriction fragment polymorphism determined using southern hybridization 总被引:2,自引:0,他引:2
Summary Regions of herpes simplex virus type 1 (HSV-1) DNA with variation in the size of restriction endonuclease fragments were identified by comparison of theBam HI,KpnI orSalI restriction endonuclease digestion patterns among 15 HSV-1 isolates after hybridization with specific32P-labeled cloned HSV-1 DNA fragments. Of the types of restriction fragment polymorphism identified, one was a strain with a distinctly different restriction fragment than the prototype (loss or gain of restriction sites). Another type, the specific fragment varied only in size among strains. Thirteen distinct variations were identified. Ten were mapped to the unique sequence of the L component; two to the inverted repeat of the L component and one to the inverted repeat of the S component. The presence of a common ancestor from which some isolates of HSV-1 might derive was deduced from an analysis of the distribution of the thirteen variations among the 15 HSV-1 isolates.With 8 FiguresOn leave from the Chemo-Sero-Therapeutic Institute, Kumamoto, Japan. 相似文献
86.
Thalamo-parietal fibers originating from the ventroanterior-ventrolateral (VA-VL) complex in the cat were labeled with Phaseolus vulgaris leucoagglutinin (PHA-L) and examined by light and electron microscopy. PHA-L (2.5% aqueous solution) was injected iontophoretically through micropipets with anodal current pulses into the VA-VL complex. PHA-L-labeled terminals were distributed in the lateral and the suprasylvian gyri in the superficial and deep cortical layers. In layer I, horizontal varicose fibers and terminals were conspicuous in the upper one-third and were widely distributed. In the deeper cortical layers (layers III-V), varicose fibers and terminals were detected in moderate numbers. Electron microscopic examination revealed that the labeled terminals formed asymmetrical synapses on the dendritic spines of spiny neurons. These morphological findings appeared to be consistent with our previous intracellular recordings in this cortex. 相似文献
87.
The cells from 5 cases of non-lymphocytic leukemia were investigated by immunoelectron microscopy using an anti-granulocyte antibody, clone 1G10 (New England Nuclear), to clarify the nature of immature leukemic cells. Reaction products on the surface of the leukemic cells were composed of two layers, an inner translucent and an outer dense granular zone. Although non-leukemic cells of the granulocytic series in various stages of maturation between promyelocytes and neutrophils were all positive for the antigen-antibody reaction, non-neoplastic monocytes and lymphocytes were all negative. Using this method, it was possible to diagnose the undifferentiated leukemic cells that were negative for myeloperoxidase. Furthermore, the results of our present study suggest the possibility that the antibody 1G10 may be useful for distinguishing granulocytic cells from cells of monocytic lineage. 相似文献
88.
T Kato M Takeya K Takagi K Takahashi 《Laboratory investigation; a journal of technical methods and pathology》1990,62(5):635-645
Malignant fibrous histiocytoma was produced in rats by injection of 9,10-dimethyl-1,2-benzanthracene into their knee joints. The original tumors consisted mainly of fibroblast-like cells and histiocyte-like cells, often intermixed with bizarre giant cells, and they frequently showed the storiform-pleomorphic pattern. By immunohistochemistry, anti-rat macrophage monoclonal antibodies, TRPM-3, RM-1, and Ki-M2R, and anti-rat leukocyte common antigen reacted to the histiocyte-like cells but not to the fibroblast-like cells. By the single cell cloning method, we established six tumor cell lines, none of which reacted with the anti-rat macrophage monoclonal antibodies, possessed any Fc receptors, or conducted immune phagocytosis and Latex particle phagocytosis. The ultrastructure of the cloned tumor cells resembled that of long-term cultured dermal fibroblasts. Collagen production by the tumor cells was demonstrated immunohistochemically with a monoclonal antibody for type I collagen. Inoculation of the cloned tumor cells into rats produced tumors with the histology of malignant fibrous histiocytoma and induced prominent macrophage infiltration. In the rat tumors produced by the inoculation of [3H]thymidine labeled cells, no reactivity of tumor cells with the anti-rat macrophage monoclonal antibodies was observed. Transplantation of the cultured rat tumor cells into nude mice produced tumors similar in histology to the original rat malignant fibrous histiocytoma. Tumor cells in nude mice induced marked macrophage infiltration as detected by immunohistochemistry with the anti-mouse macrophage monoclonal antibody F4/80. No differentiation of tumor cells into macrophages was detected, since no cells were stained with biotinylated anti-rat macrophage monoclonal antibody TRPM-3. By the flash labeling method with [3H]thymidine, infiltrating macrophages in the nude mouse tumors were proved to derive from the bone marrow of the host animals. These results indicate a possible experimental reproduction of malignant fibrous histiocytoma by proliferation of malignant fibroblasts or their related cells in combination with macrophage infiltration. 相似文献
89.
T. Tsuji P. Shrestha K. Yamada H. Takagi F. Shinozaki K. Sasaki K. Maeda M. Mori 《Virchows Archiv : an international journal of pathology》1992,420(5):377-383
Summary Proliferating cell nuclear antigen (PCNA) is a nuclear protein synthesized in the late G1 and S phase of the cell cycle and immunohistochemical detection of the protein represents a useful marker for the proliferating fraction of cells in tissue specimens. A series of malignant and pre-malignant lesions of the oral cavity and skin were evaluated by the streptavidin biotin immunoperoxidase method for detection of this protein. Monoclonal anti-PCNA antibody (PC 10) labelled proliferating cells in all cases with varying intensity of nuclear staining. In squamous cell carcinoma (n=48), PCNA positivity correlated with the differentiation and atypia of the tumour cells; however, in poorly differentiated tumours, the relationship between PCNA expression and proliferation was lost. Basal cell carcinoma showed an increased growth fraction in tiny epithelial nests (mean 43.8, SD 6.0,n=20) than in neoplastic basal cells (mean 30.1, SD 6.9,n=8). The growth fractions were significantly higher in the pre-malignant lesions (leukoplakia, mean 22.3, SD 7.7,n=14; Bowen's disease, mean 45.2, SD 11.7,n=12; senile keratosis, mean 41.2, SD 7.0,n=12) than in the normal mucosa (mean 9.8, SD 4.9,n=10), suggesting that cellular growth fractions correlate with the degree of dysplasia in pre-malignant lesions. 相似文献
90.
S Nakamura N Takagi K Kitoh T Koshikawa K Hayashi K Yamamoto H Suzuki A Oyama R Ueda T Suchi 《Acta pathologica japonica》1992,42(2):141-149
A case of angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) which showed widespread involvement of the gastrointestinal tract is reported. A lymph node biopsy specimen showed the characteristic histological features of AILD. During the progression of the illness, lymphomatous lesions developed in the gastrointestinal tract, complicated by cytomegalovirus infection. A double immunoenzymatic study using a combination of Ki-67 antibody and antibodies against surface antigens demonstrated that CD3+, CD4+, and/or T-cell receptor (TCR) beta+ cells were predominant (67-68%) among the population of proliferating Ki-67% cells, rather than CD8+ or CD22+ cells. Clonal rearrangement of the TCR beta chain gene was also detected. These findings provide further evidence for the neoplastic nature of lesions of this type, and the diagnosis of peripheral T-cell lymphoma. 相似文献