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31.
Intracytoplasmic lumina (ICL) in human oviduct epithelium were investigated with transmission electron microscopy. ICL were found in 43 out of 60 cases examined. They were ultra-structurally characterized by microvilli lining the lumina, periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) staining-positive finely granular material in the lumina, and secretory vesicles in the cytoplasm surrounding the lumina. Although ICL were observed at various heights within the epithelium, they were mainly seen in basally located cells that did not face the oviduct lumen. Various stages of formation and development of ICL were observed in the basally located epithelial cells with secretory activities. Primary ICL were originated in the cytoplasm where the secretory granules were aggregated with smooth-surfaced tubular vesicles. Electron microscopic observations after PA-TCH-SP staining revealed that ICL were formed by fusion of the secretory granules with the tubular vesicles. ICL were enlarged into round profiles by further fusion of secretory granules and tubular vesicles, and subsequently opened to the oviduct lumen, or fused to each other to develop into large extracellular cysts within the epithelium. 相似文献
32.
Peter Reimer Sanjay Saini Ken K. Kwong Mark S. Cohen Ralph Weissleder Thomas J. Brady 《Journal of magnetic resonance imaging : JMRI》1994,4(3):331-335
To develop guidelines for clinical magnetic resonance imaging of the liver, the authors undertook an animal study to investigate the effect of dose and pulse sequence on liver signal intensity in gadopentetate dimeglumine—enhanced echo-planar imaging. Serial imaging of the liver was performed in anesthetized rats after intravenous administration of five different doses (0.01, 0.05, 0.1, 0.2, and 0.5 mmol/kg) of contrast agent, with six different pulse sequences. The results show that gadopentetate dimeglumine—enhanced echo-planar images obtained during the perfusion phase can yield either positive (due to increased T1 relaxation rates) or negative (due to susceptibility-induced increased T2 relaxation rates) liver enhancement depending on choice of pulse sequence and dose. At the current clinically recommended dose of 0.1 mmol/kg, maximal liver signal enhancement was seen with a T1-weighted inversion-recovery sequence, while maximal liver signal diminution was seen with a T2*-weighted gradient-echo sequence. The authors conclude that gadopentetate dimeglumine—enhanced echo-planar imaging can provide T1, T2, and T2* contrast that may be exploited for both lesion detection and lesion characterization. 相似文献
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Masayuki Imamura Yutaka Shimada Yuhji Kanda Manabu Fukumoto Ken Yanagibashi Tokiharu Miyahara Takayoshi Tobe 《Surgery today》1992,22(5):409-415
In order to decrease the perioperative complications by preoperative cisplatin chemotherapy, the preoperative single administration of cisplatin (30 mg/m2) was performed weekly from one to six times in 36 consecutive patients with esophageal cancer classified as higher than Stage II. The survival curve of 17 patients in Stage III was significantly better (P<0.05) than that of patients who had been treated without preoperative cisplatin treatment. In 3 of the 12 patients who had locally invasive cancer, either the main tumors or the metastatic lymph nodes, which had invaded the trachea or the left main bronchus, sufficiently receded, so that a curative esophagectomy became possible; 2 of them have survived over 33 months while 1 died of pneumonia 33 months after surgery. The number of perioperative complications was minimal, and thus, we consider that the postoperative use of cisplatin and fluorouracil is indicated in patients in whom a histological response is noted in the resected specimens.This work was partially supported by Grant No. 02454315 from the Japanese Ministry of Education 相似文献
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We describe a case of elastosis perforans serpiginosa with additional findings of degenerative skin changes. A 20-year-old man with hepatolenticular degeneration, under prolonged treatment with D-penicillamine, presented with a circular or serpiginous arrangement of nuchal papules. Histopathologically, transepidermal channels were accompanied by granulomatous reactions, with several giant cells engulfing elastic fibers. In addition to these findings of a typical elastosis perforans serpiginosa, we observed scar-like skin changes inside the circular arrangement of the papules. At the scar-like tissue, we found electron-microscopical evidence of randomly aggregated thin collagen fibers with no tendency toward systemic combined bundle formation, which is a characteristic feature of normal collagen fiber formation. Pseudoxanthoma-elasticum-like changes were observed on his neck. On his axillae and groin, slight skin thickening and wrinkling were detected. The diagnosis of elastosis perforans serpiginosa does not represent all of the manifestations or the pathological background described above. The skin manifestations described here represent not only an elastosis but also a total degenerative dermatosis with over-healed collagenosis. Thus, those dermatoses should be summarized as one entity, penicillamine-induced degenerative dermatosis. After considering the pathogenic background and clinical similarities, we further propose to simplify the penicillamine-induced skin manifestations to three categories: acute sensitivity reactions, bullous dermatoses, and degenerative dermatoses. 相似文献
39.
Expression of cell-matrix molecules and integrin receptors in human liver grafts during chronic rejection 总被引:1,自引:0,他引:1
Ken Hoshino Bjorn Nashan Gustav Steinhoff Rudolf Pichlmayr K. Hoshino 《Transplant international》1994,7(S1):637-640
Abstract The inflammatory response of immune cells to target cells and cell-matrix molecules is regulated by several receptor-ligand molecules. As fibrosis develops in ongoing chronic rejection after liver transplantation, it is of interest to analyze patterns of integrin receptors and cell-matrix molecules in order to study the relation between immune cells and the stromal and parenchymal cells. In the present study, we demonstrated the expression of these molecules in chronic rejected human liver grafts using immunohistochemical techniques. The results showed a differential expression and induction of integrin receptors and cell-matrix molecules on resident liver cells, especially on sinusoids, reflecting a state of chronic inflammation and a specific interaction between integrin receptors and cell-matrix molecules. The patterns of induced integrin receptors on graft-infiltrating cells was closely related to the local production of cell-matrix molecules and reflected the final sequence of a stepwise progress of the inflammatory reaction. 相似文献
40.
A human monoclonal antibody (MCA), CLN-IgG, showed cytotoxic effect in vitro against the cervical carcinoma cell line, ME-180, by antibody dependent cell-mediated cytotoxicity (ADCC). To determine which fractions of cells in peripheral blood lymphocyte (PBL) mediate ADCC, PBL were separated with nylon wool column and sheep red blood cells (SRBC). Both adherent cells (monocyte) and non-T, non-B cells showed cytotoxicity by ADCC. Human non-T, non-B cells showed higher cytotoxic activity against ME-180 cells than monocytes. Furthermore murine effector cells were less effective in ADCC than human effector cells with human MCA. 相似文献