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61.
62.
Lateral association of sphingolipids and cholesterol is considered to form membrane microdomains such as “lipid rafts” obtainable as a detergent-resistant membrane microdomain (DRM) fraction after solubilization with a non-ionic detergent and density gradient centrifugation. Since not only sphinogolipids and cholesterol, but also functional lipids such as phosphatidylinositol 4,5-bisphosphate (PIP2) are reported to be localized in DRM prepared from several cultured cells, this domain is considered to be a platform mediating lipid-signaling. Although PIP2 is considered to have pivotal roles in the nervous system, little information is available on the localization of PIP2 in the DRM within the synaptic plasma membrane (SPM) obtained from matured rat brains. In this study, in order to know the localization of PIP2 in SPM-derived DRM, we measured the amount of PIP2 in SPM and SPM-derived DRM, by the thin-layer chromatography blotting method, using a GST-fusion protein of the pleckstrin-homology domain of phospholipase Cδ1 as a PIP2 binding probe. About 10% of the PIP2 in SPM was recovered in DRM. In contrast, over 40% recovery was observed for the membrane cholesterol and sphingomyelin, and about 30% recovery was observed for phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine in the DRM were detected using the thin-layer chromatography method. Since the recovery of proteins in DRM was about 10%, the result indicates that there occurs no enrichment of PIP2 in DRM prepared from SPM. 相似文献
63.
64.
Yuichi Takeoka Shao-Yuan Chen Richard L. Boyd Koichi Tsuneyama Nobuhisa Taguchi Shinji Morita Hisashi Yago Seishi Suehiro Aftab A. Ansari Leonard D. Shultz M. Eric Gershwin 《Clinical & developmental immunology》1997,5(2):79-89
It is widely accepted that the thymic microenvironment regulates normal thymopoiesis
through a highly coordinated and complex series of cellular and cytokine interactions. A direct
corollary of this is that abnormalities within the microenvironment could be of etiologic
significance in T-cell-based diseases. Our laboratory has developed a large panel of
monoclonal antibodies (mAbs) that react specifically with epithelial or nonepithelial
markers in the thymus. We have taken advantage of these reagents to characterize the
thymic microenvironment of several genetic strains of mice, including BALB/cJ,
C57BL/6J, NZB/BlnJ, SM/J, NOD/Ltz, NOD/Ltz-scid/sz, C57BL/6J-Hcph
me/Hcph me, and
ALY/NscJcl-aly/aly mice, and littermate control animals. We report herein that control
mice, including strains of several backgrounds, have a very consistent phenotypic profile
with this panel of monoclonal antibodies, including reactivity with thymic epithelial cells
in the cortex, the medulla and the corticomedullary junction, and the extracellular matrix.
In contrast, the disease-prone strains studied have unique, abnormal staining of thymic cortex
and medulla at both the structural and cellular levels. These phenotypic data suggest
that abnormalities in interactions between developing thymocytes and stromal cells characterize
disease-prone mice. 相似文献
65.
A histological evaluation for guided bone regeneration induced by a collagenous membrane 总被引:5,自引:0,他引:5
Taguchi Y Amizuka N Nakadate M Ohnishi H Fujii N Oda K Nomura S Maeda T 《Biomaterials》2005,26(31):6158-6166
This study was designed to evaluate the histological changes during ossification and cellular events including osteogenic differentiation responding to collagenous bioresorbable membranes utilized for GBR. Standardized artificial bony defects were prepared at rat maxillae, and covered with a collagenous bioresorbable membrane. These animals were sacrificed at 1, 2, 3 and 4 weeks after the GBR-operation. The paraffin sections were subject to tartrate resistant acid phosphatase (TRAP) enzyme histochemistry and immunohistochemistry for alkaline phosphatase (ALP), osteopontin (OP) and osteocalcin (OC). In the first week of the experimental group, woven bone with ALP-positive osteoblasts occupied the lower half of the cavity. The collagenous membrane included numerous ALP-negative cells and OP-immunoreactive extracellular matrices. At 2 weeks, the ALP-, OP- and OC-immunoreactivity came to be recognizable in the region of collagenous membrane. Since ALP-negative soft tissue separated the collagenous membrane and the new bone originating from the cavity bottom, the collagenous membrane appeared to induce osteogenesis in situ. At 3 weeks, numerous collagen fibers of the membrane were embedded in the adjacent bone matrix. At 4 weeks, the membrane-associated and the cavity-derived bones had completely integrated, showing the same height of the periosteal ridge as the surrounding alveolar bones. The collagen fibers of a GBR-membrane appear to participate in osteogenic differentiation. 相似文献
66.
Immunohistochemical analysis of MCT1, MCT2 and MCT4 expression in rat plantaris muscle 总被引:3,自引:1,他引:3
Takeshi Hashimoto Shinya Masuda Sadayoshi Taguchi George A. Brooks 《The Journal of physiology》2005,567(1):121-129
All three forms of recombinant low voltage-activated T-type Ca2 + channels (Cav 3.1, Cav 3.2 and Cav 3.3) exhibit a small, though clearly evident, window T-type Ca2 + current ( I Twindow ) which is also present in native channels from different neuronal types. In thalamocortical (TC) and nucleus reticularis thalami (NRT) neurones, and possibly in neocortical cells, an I Twindow -mediated bistability is the key cellular mechanism underlying the expression of the slow (< 1 Hz) sleep oscillation, one of the fundamental EEG rhythms of non-REM sleep. As the I Twindow -mediated bistability may also represent one of the cellular mechanisms underlying the expression of high frequency burst firing in awake conditions, I Twindow is of critical importance in neuronal population dynamics associated with different behavioural states. 相似文献
67.
Doi A Okano M Akagi H Nishizaki K Taguchi T Murakami T Ohtsuka A 《Anatomical science international / Japanese Association of Anatomists》2003,78(1):62-67
The musk shrew, Suncus murinus, is one of the primitive mammals and has a pair of palatine tonsils. In the present study,
we investigated the blood microvascular architecture of the tonsil in this animal by scanning electron microscopy of corrosion
casts. The paranodular arterioles entered the lymph nodule to form a coarse capillary plexus within the nodule. Some of the
arterioles reached the dome region to give rise to a fine meshwork of dome subepithelial capillaries. This dome subepithelial
capillary network did not show any hairpin or switch-back patterns, as seen in human and rabbit tonsils. Both of the nodular
and dome capillaries were drained into the postcapillary venules in the periphery of the nodular or the paranodular region.
On the surface of these cast venules, oval-shaped indentations were seen corresponding to the luminal surface of the high
endothelial venules. These venules were collected into the large vein at the bottom of the tonsil. The blood vascular architecture
of the musk shrew tonsil is basically the same as those of other mucosa-associated lymphoid tissues in mammals. 相似文献
68.
Takeshita M Okamura S Oshiro Y Imayama S Okamoto S Matsuki Y Nakashima Y Okamura T Shiratsuchi M Hayashi T Kikuchi M 《Human pathology》2004,35(2):231-239
CD56 is an important marker for prospecting clinicopathologic features of cytotoxic T-cell and natural killer (NK)/T-cell lymphomas. We examined 22 cases of subcutaneous panniculitis-like lymphoma and classified these into CD56-positive and CD56-negative groups. The 11 CD56-negative cases were mainly in the younger age group and had systemic subcutaneous nodules without ulceration. They exhibited subcutaneous invasion by medium-sized lymphoma cells, scattered erythrophagocytosis, patchy necrosis, and little tumor invasion in the superficial dermis. Their lymphoma cells had characteristics of CD3 epsilon-, CD8-, TcR beta F1-, T-cell intracellular antigen (TIA)1-, and granenzyme B-positive cytotoxic T cells and were negative for apoptosis-promoting proteins CD95 (Fas), Bax, CPP32 (caspase 3), and p53 (DO7). Ten patients were alive despite clinical signs of hemophagocytic syndrome and relapses in 7 cases. The 11 CD56-positive cases had systemic ulcerative skin tumors composed of pleomorphic lymphoma cells with massive necrosis and little erythrophagocytosis involving the subcutis and also often the whole dermis. Their tumor cells were positive for CD3 epsilon, TIA1, granenzyme B, CD95, CD95L (Fas ligand), Bax, and CPP32. Three cases were of the TcR beta F1-positive phenotype, 1 was of the TcR gamma/delta-positive T-cell phenotype, and 6 were of the TcR beta F1- and TcR gamma/delta-negative NK/T-cell phenotype. Six cases were p53 (DO7) positive. Seven cases had complications of liver dysfunction and cytopenia, and 8 died of disease. One CD56-negative case and 3 CD56-positive cases had nuclear signals of Epstein-Barr virus-encoded RNA in their lymphoma cells. The 2 groups had significantly (P <0.01) different prognoses by Kaplan-Meier and log-rank methods. Patients with CD56-negative and CD56-positive groups had statistically different clinicopathologic, immunohistologic, and functional findings and prognoses. 相似文献
69.
Summary After intranasal inoculation of suckling rats mouse hepatitis virus multiplied mostly in the nasal epithelium; though there were no symptoms, antibodies were produced. Antibodies were also demonstrated in adult rats. These findings suggest that the rat may be a natural host for the virus.With 2 Figures 相似文献
70.
Yoshiteru Sakamoto Dr Takehiko Watanabe Hideyuki Hayashi Yoshitaka Taguchi Hiroshi Wada 《Inflammation research》1985,17(1):32-37
The effect of about one hundred compounds on the activity of histidine decarboxylase partially purified from whole bodies of fetal rats was determined. Most of them at their 10 mM concentration had little effect on the enzyme activity; but 12 compounds inhibited the enzyme to a greater extent than 30%. Among these, except for -methylhistidine that has been known to be a strong and specific inhibitor, DOPA, homocysteine, cysteine, methionine and urocanic acid were the best inhibitors; -phenyllactic acid, phenylpyruvic acid and carnosine were less strong inhibitors; valine, oxaloacetic acid andN
-methylimidazole acetic acid were weak inhibitors. Histamine had no inhibitory action. Thus, the substrate binding site of histidine decarboxylase is very rigid and specific forl-histidine. 相似文献