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31.
Influence of acetylcholine on neuronal activity of monkey amygdala during bar press feeding behavior
L zl L n rd Yutaka Oomura Yasuhiko Nakano Shuji Aou Hitoo Nishino 《Brain research》1989,500(1-2):359-368
Single neuron activity in the monkey amygdala was investigated during cue signalled conditioned bar press feeding behavior and the effects of electrophoretically applied acetylcholine (ACh) and atropine were analyzed. ACh increased the firing rate of one third of the neurons tested; these excitatory responses were inhibited by the muscarinic receptor antagonist atropine. No characteristic location of ACh-sensitive neurons was found, cells were diffusely distributed throughout the amygdala. Activity of ACh-sensitive neurons did not correlate with any particular event during the bar press feeding task. However, continuous application of ACh at low current intensity during the task significantly enhanced the task-related excitatory firing patterns, or markedly attenuated the inhibitory responses. Continuous application of atropine elicited or enhanced inhibitory response patterns. These results suggest that the cholinergic system of the monkey amygdala facilitates neuronal excitation but attenuates inhibition related to various phases of feeding behavior, such as to cue recognition, food aquisition and rewarding process. 相似文献
32.
33.
Regeneration of defects in articular cartilage in rat knee joints by CCN2 (connective tissue growth factor). 总被引:7,自引:0,他引:7
Takashi Nishida Satoshi Kubota Shunji Kojima Takuo Kuboki Kyouji Nakao Toshihiro Kushibiki Yasuhiko Tabata Masaharu Takigawa 《Journal of bone and mineral research》2004,19(8):1308-1319
CTGF/CCN2, a hypertrophic chondrocyte-specific gene product, possessed the ability to repair damaged articular cartilage in two animal models, which were experimental osteoarthritis and full-thickness defects of articular cartilage. These findings suggest that CTGF/CCN2 may be useful in regeneration of articular cartilage. INTRODUCTION: Connective tissue growth factor (CTGF)/CCN2 is a unique growth factor that stimulates the proliferation and differentiation, but not hypertrophy, of articular chondrocytes in vitro. The objective of this study was to investigate the therapeutic use of CTGF/CCN2. MATERIALS AND METHODS: The effects of recombinant CTGF/CCN2 (rCTGF/CCN2) on repair of damaged cartilage were evaluated by using both the monoiodoacetic acid (MIA)-induced experimental rat osteoarthritis (OA) model and full-thickness defects of rat articular cartilage in vivo. RESULTS: In the MIA-induced OA model, quantitative real-time RT-PCR assays showed a significant increase in the level of CTGF/CCN2 mRNA, and immunohistochemical analysis and in situ hybridization revealed that the clustered chondrocytes, in which clustering indicates an attempt to repair the damaged cartilage, produced CTGF/CCN2. Therefore, CTGF/CCN2 was suspected to play critical roles in cartilage repair. In fact, a single injection of rCTGF/CCN2 incorporated in gelatin hydrogel (rCTGF/CCN2-hydrogel) into the joint cavity of MIA-induced OA model rats repaired their articular cartilage to the extent that it became histologically similar to normal articular cartilage. Next, to examine the effect of rCTGF/CCN2 on the repair of articular cartilage, we created defects (2 mm in diameter) on the surface of articular cartilage in situ and implanted rCTGF/CCN2-hydrogel or PBS-hydrogel therein with collagen sponge. In the group implanted with rCTGF/CCN2-hydrogel collagen, new cartilage filled the defect 4 weeks postoperatively. In contrast, only soft tissue repair occurred when the PBS-hydrogel collagen was implanted. Consistent with these in vivo effects, rCTGF/CCN2 enhanced type II collagen and aggrecan mRNA expression in mouse bone marrow-derived stromal cells and induced chondrogenesis in vitro. CONCLUSION: These findings suggest the utility of CTGF/CCN2 in the regeneration of articular cartilage. 相似文献
34.
Tatsuya Okimoto Hiroshi Yahata Yasuhiko Fukuda Keisuke Hayamizu Kiyohiko Dohi 《Transplant international》1994,7(S1):629-633
Abstract A study was conducted to elucidate the mechanism of donor-pecific Mixed Lymphocyte Reaction (MLR and Cell Mediated Lymphotoxicity (CML) unresponsiveness in a renal transplant recipient with a long-term well-functioning kidney. The peripheral blood lymphocytes (PBL) of the recipient, who had not shown rejection since his transplantation 5 years previously, and those of his mother (donor), his father and two healthy third parties were examined. MLR, CML, semimicro MLR in a double chamber, interleukin-2 (IL-2) synthesis assay and limiting dilution assay were performed. This recipient showed donor-pecific MLR and CML unresponsiveness. IL-2 assay showed that the PBL of the recipient produced less IL-2 against the donor than against the father and the third parties. The addition of exogenous recombinant IL-2 (rIL-2; Takeda Co.) to the priming MLR caused a recovery of CML against the donor. A limiting dilution assay indicated that cytotoxic T cell precursor (CTLp) frequencies against the donor and father did not differ. The suppressor assay in a double chamber indicated that the PBL of the recipient stimulated by the donor PBL had a non-pecific suppressive effect on MLR, CML and IL-2 synthesis of the PBL across the Major Histocompatibility Complex (MHC) barrier. This suppressive effect was abolished by OKT3 or OKT8 monoclonal antibody and complement. Thus, the recipient had donor-pecific suppressor T cells that produced a humoral non-pecific suppressive factor only when stimulated by the donor PBL, and this factor suppressed PLR and CML by inhibiting IL-2 synthesis of the PBL. 相似文献
35.
H. Sone Y. Okuda M. Mizutani Y. Kawakami C. Bannai K. Yamashita 《Postgraduate medical journal》1995,71(840):613-616
The effects of nilvadipine on the peripheral circulation in the lower extremities using a duplex system of two-dimensional colour and pulse Doppler ultrasonography were studied in 32 patients with type 2 diabetes mellitus and mild essential hypertension. The patients (19 men and 13 women) were randomly divided into treatment and control groups. The anatomical cross-sectional area and blood flow index of the dorsal pedis artery were determined by colour and pulse Doppler ultrasonography before and 60 min after administration of 4 mg nilvadipine or placebo. Pulse rate and blood pressure were measured simultaneously. There were no significant changes in pulse rate or blood pressure after administration of either drug. Both cross-sectional areas (from 4.3 +/- 0.4 to 5.2 +/- 0.5 mm2, p < 0.05) and blood flow index (from 40.3 +/- 4.3 to 58.8 +/- 9.0, p < 0.05) were significantly increased in the treatment group, whereas there were no significant changes in either measurement in the control group. The findings showed that a single administration of nilvadipine increases blood flow in the dorsal pedis arteries of diabetic patients. 相似文献
36.
H Masuda S Kawakami H Nagamatsu K Nagahama T Yamada T Negishi 《Hinyokika kiyo. Acta urologica Japonica》1992,38(7):821-824
The identification and diagnosis of thyroid metastases from renal cell carcinoma are rare in living patients in spite of more frequent incidence during autopsy. We reported two cases of thyroid metastases from renal cell carcinoma. In both cases, histological examination revealed metastasis from renal cell carcinoma and negative immunohistological stain for thyroglobulin ruled out primary thyroid carcinoma. 相似文献
37.
Takuya Onizuka M.D. Noriyoshi Sumiya M.D. Ryosuke Aoyama M.D. Yasuhiko Fukuya M.D. Takao Jinnai M.D. 《Aesthetic plastic surgery》1990,14(1):207-213
The results of repairing cleft lip by aesthetic plastic surgery are now excellent. However, the cleft lipnose deformity is still very difficult to repair with the present techniques. A technique that can repair the cleft lip-nose deformity with good results is presented. The technique is divided into three parts: Part I consists of nasal repair of the primary cleft lip. Part II is nasal reconstruction as a secondary operation with or without lip repair. For example, nasal reconstruction may be secondary to repair of deformities of the sill, rim, limen nasi, septum, or nasal bones. Part III is an aesthetic nasal operation such as rhinoplasty, mentoplasty, or zygomaplasty. 相似文献
38.
Mitsuru Masaki Tadashi Kuroda Naoki Hosen Hisao Hirota Kazuo Terai Yuichi Oshima Yoshikazu Nakaoka Shoko Sugiyama Ryusuke Kimura Satoshi Yoshihara Manabu Kawakami Norishige Iizuka Yasuhiko Tomita Hiroyasu Ogawa Ichiro Kawase Keiko Yamauchi-Takihara 《Journal of the American Society of Echocardiography》2004,17(4):397-398
A 57-year-old man with a history of renal cell carcinoma presented with presyncope. He underwent nephrectomy years earlier followed by HLA-matched allogeneic peripheral-blood stem-cell transplantation. Echocardiographic investigation revealed a solitary right ventricle mass without contiguous vena caval or right atrial involvement. The mass was pathologically confirmed to be metastatic carcinoma in the right ventricular cavity. This case highlights the need to consider an underlying neoplastic syndrome in patients presenting isolated right ventricle mass by echocardiography. 相似文献
39.
Pharmacologic preconditioning effects: Prostaglandin E1 induces heat-shock proteins immediately after ischemia/reperfusion of the mouse liver 总被引:1,自引:0,他引:1
Ken-ichi Matsuo M.D. Shinji Togo M.D. Ph.D. Hitoshi Sekido M.D. Ph.D. Tomoyuki Morita M.D. Ph.D. Masako Kamiyama Ph.D. Daisuke Morioka M.D. Ph.D. Toru Kubota M.D. Ph.D. Yasuhiko Miura M.D. Ph.D. Kuniya Tanaka M.D. Ph.D. Takashi Ishikawa M.D. Ph.D. Yasushi Ichikawa M.D. Ph.D. Itaru Endo M.D. Ph.D. Hitoshi Goto M.D. Ph.D. Hiroyuki Nitanda M.D. Ph.D. Yasushi Okazaki M.D. Ph.D. Yoshihide Hayashizaki M.D. Ph.D. Hiroshi Shimada M.D. Ph.D. 《Journal of gastrointestinal surgery》2005,9(6):758-768
Prostaglandin E1 (PGE1) has several potential therapeutic effects, including cytoprotection, vasodilation, and inhibition of platelet aggregation. This study investigates the protective action of PGE1 against hepatic ischemia/reperfusion injury in vivo using a complementary DNA microarray. PGE1 or saline was continuously administered intravenously to mice in which the left lobe of the liver was made ischemic for 30 minutes and then reperfused. Livers were harvested 0, 10, and 30 minutes postreperfusion. Messenger RNA was extracted, and the samples were labeled with two different fluorescent dyes and hybridized to the RIKEN set of 18,816 full-length enriched mouse complementary DNA microarrays. Serum alanine aminotransferase and aspartate aminotransferase levels at 180 minutes postreperfusion were significantly lower in the PGE1-treated group than in the saline-treated group. The cDNA microarray analysis revealed that the genes encoding heat-shock protein (HSP) 70, glucose-regulated protein 78, HSP86, and glutathione S-transferase were upregulated at the end of the ischemic period (0 minutes postreperfusion) in the PGE1 group. Our results suggested that PGE1 induces HSPs immediately after ischemia reperfusion. HSPs might therefore play an important role in the protective effects of PGE1 against ischemia/reperfusion injury of the liver. 相似文献
40.
A rare case of primary linitis plastica carcinoma of the colon seen in a 44 year old Japanese man is described herein. The patient had a complete obstruction of the descending colon and was treated with a loop colostomy followed shortly afterward by a left hemicolectomy. At the time of the second operation, the entire thickness of the colonic wall was found to be infiltrated by cancer cells, however, the other intraabdominal organs were free of cancerous involvement. The histopathological diagnosis made at this time was primary linitis plastica carcinoma of the descending colon. Nine months later, the patient developed an intestinal obstruction and relaparotomy revealed diffuse peritoneal dissemination. Two years after the first operation, upper GI films and a gastrofiberscopic examination revealed gastric involvement. The patient died 28 months after his initial operation, and autopsy revealed widespread metastases in the peritoneal surface, paraaortic lymph nodes, small intestine, remaining colon and stomach. 相似文献