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121.
122.
A new pseudo-peptide of Arg-Gly-Asp (RGD) with inhibitory effect on tumor metastasis and enzymatic degradation of extracellular matrix 总被引:2,自引:0,他引:2
Hideki Fujii Naoyuki Nishikawa Hiroyuki Komazawa Makoto Suzuki Masayoshi Kojima Isamu Itoh Aya Obata Koichi Ayukawa Ichiro Azuma Ikuo Saiki 《Clinical & experimental metastasis》1998,16(1):94-104
A series of pseudo-peptide analogs of the Arg-Gly-Asp (RGD) sequence of fibronectin have been synthe-sized, and their anti-metastatic effects in mice and inhibitory effects on tumor cell invasion in vitro have been examined. The partially modified retro pseudo-peptide of RGD, Rrev-COCH2CO-D (FC-63), was more effective in inhibiting tumor metastasis than the original RGDS peptide. Replacement of the malonyl moiety of FC-63 with a carboxyethylene linkage (Rrev-COCH2CH2-D, FC-303 ) achieved more potent inhibition of lung metastasis of melanoma cells than FC-63. Among the analogs, FC-336, a p-xylylendiamine derivative having two FC-303 moieties, showed the most potent inhibitory effect on experimental lung metastasis produced by i.v. co-injection with B16-BL6 melanoma or colon 26 M3.1 cells in a dose-dependent manner. Multiple administrations of FC-336 after tumor inoculation also showed efficient therapeutic potency against spontaneous lung metastasis of B16-BL6 melanoma in mice. Furthermore, FC-336 effectively inhibited the invasion, migration and adhesion of tumor cells in vitro, but its inhibitory effects were not more than those of RGDS peptide. Zymography analysis revealed that FC-336 inhibited the degradation of gelatin substrate by matrix metalloproteinases (MMPs) produced by tumor cells, while the RGDS peptide did not affect the enzymatic degradation. These findings indicate that the pseudo-peptides of the RGD sequence, possessing the inhibitory property of the degradation by MMPs differently from original RGD-containing peptides, may be advantageous and useful in preventing tumor metastasis. © Rapid Science 1998 相似文献
123.
Kuwanons N and O, two new flavonoid derivatives with a fused dihydrochalcone partial moiety, and four known flavonoid derivatives, morusin, kuwanons G, H, and K, were isolated from the ethyl acetate extract of the root bark of MORUS LHOU (SER.) Koidz. The structures of kuwanons N and O were shown to be 1 and 2, respectively, on the basis of spectral data. They are regarded biogenetically as Diels-Alder adducts of a chalcone and a dehydroprenyl flavonoid. 相似文献
124.
Yuki Ohya Masayoshi Tasaki Shintaro Hayashida Nobuhiro Katayama Toru Tsuchida Kazumi Kuriwaki Mitsuharu Ueda Yukihiro Inomata 《Transplantation proceedings》2021,53(4):1313-1316
BackgroundCarpal tunnel syndrome is the most common compression syndrome of the peripheral nerve. Transthyretin amyloidosis and dialysis-related β2-microglobulin amyloidosis are known causes of carpal tunnel syndrome.Case ReportA Japanese woman showed carpal tunnel syndrome 16 years after a domino liver transplantation (DLT) from the donor with hereditary transthyretin amyloidosis. DLT indication was congenital extrahepatic portosystemic shunt, and the patient had been put on maintenance hemodialysis because of chronic kidney disease 6 years before DLT. Moreover, the amyloid precursor protein of the patient was histologically confirmed not to be β2-microglobulin, but transthyretin.ConclusionsThe existence of amyloid was speculated when the patient who underwent DLT from hereditary transthyretin amyloidosis showed carpal tunnel syndrome. Additionally, elucidating the amyloid precursor protein when the patient has another cause of amyloidosis is necessary. 相似文献
125.
126.
Four new isoprenylated xanthones, cudraxanthone H,I,J, and K were isolated from the ethanol extract of the root bark of CUDRANIA TRICUSPIDATA (Carr.) Bur. (Moraceae), collected in China. The structures of cudraxanthones H,I,J, and K were shown to be 1- 4, respectively, on the basis of chemical and spectral evidence. 相似文献
127.
Three new isoprenylated xanthones, cudraxanthones E, F, and G along with a known xanthone, 6-deoxyisojacareubin, were isolated from the ethanol extract of the root bark of CUDRANIA TRICUSPIDATA (Moraceae), collected in China. The structures of cudraxanthones E, F, and G were shown to be 1-3, respectively, on the basis of spectral evidence. 相似文献
128.
Reiichiro Kondo Yasuko Iwakiri Masayoshi Kage Hirohisa Yano 《Pathology international》2023,73(9):381-393
Liver is the largest solid organ in the abdominal cavity, with sinusoid occupying about half of its volume. Under liver disease, hemodynamics in the liver tissue dynamically change, resulting in injury to liver sinusoidal endothelial cells (LSECs). We discuss the injury of LSECs in liver diseases in this article. Generally, in noninflamed tissues, vascular endothelial cells maintain quiescence of circulating leukocytes, and unnecessary blood clotting is inhibited by multiple antithrombotic factors produced by the endothelial cells. In the setting of inflammation, injured endothelial cells lose these functions, defined as inflammatory endotheliopathy. In chronic hepatitis C, inflammatory endotheliopathy in LSECs contributes to platelet accumulation in the liver tissue, and the improvement of thrombocytopenia by splenectomy is attenuated in cases with severe hepatic inflammation. In COVID-19, LSEC endotheliopathy induced by interleukin (IL)-6 trans-signaling promotes neutrophil accumulation and platelet microthrombosis in the liver sinusoids, resulting in liver injury. IL-6 trans-signaling promotes the expression of intercellular adhesion molecule-1, chemokine (C-X-C motif) ligand (CXCL1), and CXCL2, which are the neutrophil chemotactic mediators, and P-selectin, E-selectin, and von Willebrand factor, which are involved in platelet adhesion to endothelial cells, in LSECs. Restoring LSECs function is important for ameliorating liver injury. Prevention of endotheliopathy is a potential therapeutic strategy in liver disease. 相似文献
129.
Yoshida M Abe O Uchino J Kikuchi K Abe R Enomoto K Tominaga T Fukami A Sakai K Koyama H Sugimachi K Nomura Y Hattori T Ogawa N 《Breast cancer (Tokyo, Japan)》1997,4(2):103-113
A multi-center, randomized controlled collaborative study was conducted in 310 institutions located throughout Japan for 3 years and 9 months from February 1985 until October 1988 to evaluate the efficacy of post-operative adjuvant therapy for patients who had previously undergone curative surgery for treatment of Stage IIIa breast cancer. Patients with estrogen receptor-positive [ER( + )] breast cancer were treated with two types of regimens, ie, cyclophosphamide + adriamycin + fluorouracil (CAF; 2 cycles) + Futraful (FT) or CAF (2 cycles) + FT + tamoxifen (TAM), and the clinical benefit of additional use of TAM was evaluated. Of the 509 ER( + ) patients registered for the trial, 473 patients (92.9%) were eligible for evaluation. The 5-year survival rate was 77.2% for the CAF + FT group and 74.6% for the CAF + FT+TAM group, and the 5-year disease-free survival rate was 56.7% for the CAF+FT group and 59.2% for the CAF + FT + TAM group. Neither the survival rate nor the disease-free survival rate differed significantly between the groups. Analyses by factor revealed that the 5-year disease-free rate for lymph node-negative patients in the CAF + FT + TAM group was significantly higher than that for the corresponding patients in the CAF + FT group. No differences were noted in the incidence of adverse reactions between the two treatment groups, other than an increase in LDH (the frequency of which was higher in the CAF + FT+TAM group than in the CAF + FT group). Patients with estrogen receptor-negative [ER( -)] breast cancer were treated with two types of regimens, ie, CAF + FT or CAF + FT + adriamycin (ADR), and the clinical benefit of the combined use of intermittent doses of ADR was evaluated. Of the 514 ER(-) patients registered in the trial, 478 (93.0%) were eligible for evaluation. The 5-year survival rate was 64.9% for the CAF + FT group and 63.0% for the CAF + FT + ADR group, and the 5-year disease-free survival rate was 59.2% for both CAF + FT and CAF + FT + ADR groups. Neither the survival rate nor the disease-free survival rate differed significantly between the groups. There were no significant differences between these groups in analyses by nodal or menopausal status. The incidences of adverse reactions including anorexia, nausea/vomiting and alopecia were higher in the CAF + FT+ADR group than in the CAF + FT group. 相似文献
130.
Omoto M Imai T Seki K Nomura R Otahara Y 《Environmental health and preventive medicine》1997,2(3):105-116
Based on the fact that chemical products such as binding agents are produced by mixing three kinds of phosphates with different
ratios, we mixed metaphosphate, polyphosphate and pyrophosphate. Each was made to Na-phosphate, K-phosphate, and Ca-phosphate
and each was mixed with commercial feeds so that the content of P would be approximately 0.1, 0.15, 0.3, 0.4, 0.6 and 1.0%.
The prepared pellets were given to ICR, CF # 1 and AKR strains of mice at 29 days of age for 680 days and observations were
made through this experimental period at different stages. The observations were also carried out on the mice administered
with the experimental feeds for 1.5 months from 9 to 10.5 months of age. The observations were compared with those of the
control group at all times. As a result, plasma 1 α, 25 (OH)2 D3 and P levels were always significantly higher in the phosphate administered groups relative to the control. Urine P and Fe
increased while urine Ca decreased in the phosphate-treated groups.
The effect of phosphates on the bones was studied taking soft X-ray pictures of hind legs and applying microdensitometry to
them. Through these observations we recognized thinning of the cortex of bones, reduction of marrow trabecules and development
of osteophyte. Histological observations disclosed that changes in knee joint tissues were apparent; that is, a decrease in
or an irregular loss of the number of cells in superficial, intermediate, and radial strata of the joint cartilage, proliferation
of subchondral bone, and the development of osteophytes were noted. As for muscles, diameters of musclar fibers became smaller;
in particular, type II fibers showed greater shrinkage. Regarding kidneys, swelling and atrophy of glomerular capillaries,
proliferation of mesangial cells, nephroselerosis, swelling, thinning, and loss of tubular epithelium, interstitial tissue
inflammation, development of cylindruria, and deposition of calcium were observed. All these changes seem to be a particularly
advanced aspect of the changes which are more pronounced with increasing dose and age.
These changes were found even in the group administered with the feed containing 0.1% phosphorus, and, these changes were
dependent on the concentration level of P. It was observed that administration to older subjects for a short term (1.5 months)
produced effects stronger than those to younger subjects administered for a long term (10.5 months).
The effects of condensed Ca-phosphate on bones were similar to those of condensed Na- and K-phosphates, and, hence, it was
supposed that these effects were caused by phosphate radicals.
An erratum to this article is available at . 相似文献