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51.
Keratinocyte intercellular adhesion molecule (ICAM)-I expression is induced by interferon (IFN)-gamma. It has been previously reported that IFN-beta suppresses IFN-gamma-induced ICAM-I expression in A431 cells, a human squamous cell carcinoma cell line. In this study, the suppression mechanisms were investigated at the post second messenger level. Both 12-O-tetradecanoylphorbol-13-acetate (TPA) and calcium ionophore (A23187) induce ICAM-I expression in A431 cells. ICAM-I expression induced by either was not suppressed with cotreatment with IFN-beta. Furthermore, IFN-beta did not inhibit the translocation of protein kinase C (PKC) by TPA. It appears that the pathways involved in ICAM-I expression induced by activation of PKC or increased in intracellular Ca++ are not affected by IFN-beta. 相似文献
52.
53.
Opioid supplements are often required in total intravenous anesthesia (TIVA). Most ϰ-opiate receptors are found in the spinal
cord, wherea μ-opiate receptors are widespread throughout the brain and spinal cord. Buprenorphine has a strong μ-action with
a minute ϰ-action, while eptazocine stimulates ϰ-receptors only. From these, epidural eptazocine is expected to exert strong
spinal analgesia by ϰ-stimulation without μ-action, which produces circulatory and respiratory depression. Therefore, the
clinical effects of epidural opioids on circulation, respiration, and analgesia were compared. Continuous epidural administration
of eptazocine or buprenorphine was combined with TIVA in patients scheduled for elective abdominal surgery. Epidural opioid
administration was continued throughout and for 72h after anesthesia. A significant analgesic effect (P<0.01) of epidural eptazocine without circulatory and respiratory depression was observed. With epidural buprenorphine, circulatory
and respiratory depression during and immediately after anesthesia were significant (P<0.05). These results suggest that medullary μ-stimulation by an epidural opioid induces circulatory (hypervagotonicity and
hypervagosensitivity) and respiratory depression, while ϰ-stimulation produces only minimal effects on circulatory and respiratory
systems. 相似文献
54.
Microsurgical and magnetic resonance imaging anatomy of the cerebello-medullary fissure and its application during fourth ventricle surgery. 总被引:3,自引:0,他引:3
The cerebellomedullary fissure, the only entrance or exit to the fourth ventricle, is surrounded rostrally by the cerebellar tonsils and the biventral lobules and caudally by the medulla oblongata, the tela choroidea, and the lateral recesses. This fissure is an important route in operations on the fourth ventricle. We studied the microsurgical and magnetic resonance imaging (MRI) anatomy of the fissure by using autopsied normal cerebellum. MRI revealed that the fissure is visible as a slit and is indicated by the enhanced choroid plexus and the flocculus. Oriented by the anatomical information thus obtained, we have surgically treated nine patients with a tumor either in or around the fourth ventricle. Preoperative MRI clearly demonstrated the tumors in relation to the cerebellomedullary fissure. It revealed the precise anatomical location and extension of the tumor, not only its inferior extension but also its lateral one. The MRI findings and microsurgical anatomy of the cerebellomedullary fissure were quite useful for the removal of the tumors in the fourth ventricle. 相似文献
55.
56.
Hyperthermo-chemo-radiotherapy as a definitive treatment for patients with early esophageal carcinoma. 总被引:1,自引:0,他引:1
H Matsuda S Tsutsui M Morita K Baba K Kitamura H Kuwano K Sugimachi 《American journal of clinical oncology》1992,15(6):509-514
Ten patients with early stage esophageal carcinoma were treated with hyperthermo-chemo-radiotherapy (HCR) without surgery. The reasons for the inoperability of these patients included medically inoperable unresectable cancers, advanced age, and/or refusal to undergo surgery. The diagnosis of early esophageal carcinoma was determined by esophagograms, endoscopy, and ultrasonography. Squamous cell carcinoma was histopathologically confirmed in each case. Each patient underwent four to nine sessions of hyperthermic treatment combined with external irradiation and chemotherapy using bleomycin; eight of these patients received additional radiation, and two terminated treatment after the HCR therapy. The tumors in all patients showed either a complete response (CR) or a partial response (PR) after HCR therapy; in two patients viable cancer cells remained, but later disappeared after additional radiation. Five patients experienced no local recurrence for 12 to 70 months and are now alive and doing well, three died of other medical conditions without any evidence of esophageal cancer, and two died of recurrent esophageal cancer 20 to 27 months after initial admission. All ten patients tolerated the HCR well without any systemic side effects. However, in two patients, esophageal erosion was recognized endoscopically. HCR therapy therefore deserves serious consideration when treating patients with small malignant lesions of the esophagus who, for various reasons, are unable to undergo surgery. 相似文献
57.
Masato YASUI Hiroyuki TANAKA Toshiyuki ITO Yoshiki SEINO 《Nephrology (Carlton, Vic.)》1997,3(5):339-346
Summary: Transforming growth factor-α (TGF-α) and epidermal growth factor (EGF) are structurally related mitogenic polypeptides. They share the same receptor; EGF receptor. the EGF receptor is widely expressed in human fetal tissues including the kidney, but little is known about the role of TGF-α/EGF/EGF receptor system in human fetal kidney. the expression of TGF-α, EGF and their common receptor was investigated immunohistochemically in the human fetal kidneys. In the cortex, immunoreactivity for TGF-α was found in the differentiating proximal tubules. In contrast, immunoreactivity for EGF was present in the thick ascending limbs of the Henle's loop (TAL) and medullary collecting duct cells (CD). Immunoreactivity for their common receptor was present mainly in the TAL and medullary CD. These data support the assumption that the system of TGF-α, EGF and its receptor has an important role in the proliferation and differentiation of the TAL and medullary CD. the different localization of TGF-α and its receptor may indicate that TGF-α acts through a paracrine mechanism. the co-localization of EGF and its receptor in the TAL and medullary CD suggests that EGF may act as an autocrine growth factor. 相似文献
58.
Songji Zhao Yuji Kuge Takafumi Mochizuki Toshiyuki Takahashi Kunihiro Nakada Masayuki Sato Toshiki Takei Nagara Tamaki 《Journal of nuclear medicine》2005,46(4):675-682
The biologic mechanisms involved in the intratumoral heterogeneous distribution of 18F-FDG have not been fully investigated. To clarify factors inducing heterogeneous 18F-FDG distribution, we determined the intratumoral distribution of 18F-FDG by autoradiography (ARG) and compared it with the regional expression levels of glucose transporters Glut-1 and Glut-3 and hexokinase-II (HK-II) in a rat model of malignant tumor. METHODS: Rats were inoculated with allogenic hepatoma cells (KDH-8) into the left calf muscle (n = 7). Tumor tissues were excised 1 h after the intravenous injection of 18F-FDG and sectioned to obtain 2 adjacent slices for ARG and histochemical studies. The regions of interest (ROIs) were placed on ARG images to cover mainly the central (CT) and peripheral (PT) regions of viable tumor tissues and necrotic/apoptotic (NA) regions. The radioactivity in each ROI was analyzed quantitatively using a computerized imaging analysis system. The expression levels of Glut-1, Glut-3, and HK-II were determined by immunostaining and semiquantitative evaluation. The hypoxia-inducible factor 1 (HIF-1) was also immunostained. RESULTS: ARG images showed that intratumoral 18F-FDG distribution was heterogeneous. The accumulation of 18F-FDG in the CT region was the highest, which was 1.6 and 2.3 times higher than those in the PT and NA regions, respectively (P < 0.001). The expression levels of Glut-1, Glut-3, and HK-II were markedly higher in the CT region (P < 0.001) compared with those in the PT region. The intratumoral distribution of 18F-FDG significantly correlated with the expression levels of Glut-1, Glut-3, and HK-II (r = 0.923, P < 0.001 for Glut-1; r = 0.829, P < 0.001 for Glut-3; and r = 0.764, P < 0.01 for HK-II). The positive staining of HIF-1 was observed in the CT region. CONCLUSION: These results demonstrate that intratumoral 18F-FDG distribution corresponds well to the expression levels of Glut-1, Glut-3, and HK-II. The elevated expression levels of Glut-1, Glut-3, and HK-II, induced by hypoxia (HIF-1), may be contributing factors to the higher 18F-FDG accumulation in the CT region. 相似文献
59.
Takeuchi Hirofumi Yamamoto Hiromitsu Niwa Toshiyuki Hino Tomoaki Kawashima Yoshiaki 《Pharmaceutical research》1996,13(6):896-901
Purpose. The mucoadhesiveness of polymer-coated liposomes was evaluated to develop a novel drug carrier system for oral administration of poorly absorbed drugs such as peptide drugs.
Methods. Multilamellar liposomes consisting of dipalmitoylphosphatidylcholine (DPPC) and dicetyl phosphate (DCP) (DPPC:DCP = 8:2 in molar ratio) were coated with chitosan (CS), polyvinyl alcohol having a long alkyl chain (PVA-R) and poly (acrylic acid) bearing a cholesteryl group. The adhesiveness of the resultant polymer-coated liposomes to the rat intestine was measured in vitro by a particle counting method with a Coulter counter. The CS-coated liposomes containing insulin were administered to normal rats and the blood glucose level was monitored.
Results. The existence of polymer layers on the surface of liposomes was confirmed by measuring the zeta potential of liposomes. The CS-coated liposomes showed the highest mucoadhesiveness and the degree of adhesion was dependent on the amount of CS on the surface of the liposomes. The blood glucose level of rats was found to be significantly decreased after administration of the CS-coated liposomes containing insulin. The lowered glucose level was maintained for more than 12h after administration of the liposomal insulin, which suggested mucoadhesion of the CS-coated liposomes in the intestinal tract of the rats. 相似文献
60.
Shohachi Suzuki Satoshi Nakamura Hideki Ishida Takanori Sakaguchi Atsushi Serizawa Hiroyuki Konno Shozo Baba Hiroyuki Muro Isao Kosugi Eisaku Gu 《Surgery today》1996,26(8):635-639
Hepatic angiomyolipoma is a rare tumor composed of spindle-shaped and epithelioid smooth muscle cells, adipose tissue, and proliferating blood vessels. We report the first documented case of this tumor developing in a patient with ulcerative colitis. A solitary tumor (7.5×7.5×7cm) was detected in the left lateral segment of the liver and a left hepatic lobectomy was performed. The diagnosis of angiomyolipoma was confirmed by a pathological examination. We also review the literature on previously reported cases of hepatic angiomyolipoma. 相似文献