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971.
It has been shown that Wallerian degeneration, an anterograde degeneration of transected axons, is markedly delayed in a mutant mouse called slow Wallerian degeneration (Wld(S)). These mice also show resistance to axonal degeneration caused by microtubule depolymerizing drugs, suggesting that axonal microtubules are stabilized. Here, we have focused on tubulin acetylation, a post-translational modification associated with microtubule stability. We found that the basal level of microtubule acetylation was increased in cultured cerebellar granule cells from Wld(S) mice. Nicotinamide but not 3-aminobenzamide, an inhibitor for poly(ADP)ribose polymerase, enhanced tubulin acetylation and resistance to axonal degeneration in cultured cerebellar granule cells from wild-type (WT) mice, suggesting that mammalian Sir2-related protein (SIRT) 2, a nicotinamide adenine dinucleotide (NAD)--dependent tubulin deacetylase, could modulate resistance to axonal degeneration. Indeed, the levels of NAD and SIRT2 were decreased in the cytoplasm from Wld(S) granule cells. Moreover, SIRT2 overexpression abrogated microtubule hyperacetylation and resistance to axonal degeneration in these cells. Conversely, SIRT2 knockdown by using a lentiviral vector expressing small interfering RNA, enhanced microtubule acetylation and resistance to axonal degeneration in WT granule cells. Taken together, these results suggest that SIRT2-mediated tubulin deacetylation is involved in both microtubule hyperacetylation and resistance to axonal degeneration in Wld(S) granule cells. 相似文献
972.
Matsubayashi Hidehiko; Sugi Toshitaka; Arai Tadashi; Shida Masako; Kondo Akane; Suzuki Takahiro; Izumi Shun-ichiro; McIntyre John A. 《Human reproduction (Oxford, England)》2007,22(11):3043-3044
Sir, We have read the paper of Buckingham et al. (2006) with considerableinterest because we have recently published a related study(Matsubayashi et al., 2006). Buckingham et al. (2006) reportedthat antiphospholipid antibodies (aPLs) do not appear selectivelyconcentrated in follicular fluids and, when present, do notadversely affect the reproductive outcome 相似文献
973.
Cancer screening with PET: advantages and limitations 总被引:1,自引:0,他引:1
Kawada S Suzuki Y Hinohara S Koide S Ono Y Ashikaga H 《Rinsho byori. The Japanese journal of clinical pathology》2007,55(7):656-667
Warburg first reported that tumours are characterized by abnormally increased glucose metabolism accompanied by increase production of lactate. This is a basic principle underlying cancer detection by the glucose analogue 18-F-fluoro-2-deoxy-D-glucose (FDG). FDG positron emission tomography (PET) is currently used widely to examine virtually any part of the body in order to detect tumours, e.g., lung, breast, colorectal, pancreatic and head and neck cancers, malignant lymphoma and malignant melanoma. The advantage of whole-body FDG-PET in comparison with the other imaging modalities is that it allows the entire body to be surveyed seamlessly within a reasonably short period. Furthermore, the staging of most cancers can be determined. The characteristics of whole-body FDG-PET seem to satisfy the requirements for cancer screening. PET used simultaneously with conventional tests can prevent the overlooking of cancer, reduce false-positive results and assist in the interpretation of CT and MRI images. Thus, PET can play a supportive role when used with conventional screening tests. In 1994, PET was applied to cancer screening for the first time at our Imaging Center at Lake Yamanaka in Japan. Within 12 years after starting, a total of 10,292 asymptomatic individuals (6,227 men and 4,065 women; mean age, 52.2 and 52.9 years) participated in 29,090 screening sessions. As a result, malignant tumours were demonstrated in 355 of the 10,292 participants (2.61%). PET findings were true-positive in 175 of the 355 cancers (49.3%). 相似文献
974.
Suzuki T Matsuzaki T Hagiwara H Aoki T Takata K 《ACTA HISTOCHEMICA ET CYTOCHEMICA》2007,40(5):131-137
Tremendous progress in recent computer-controlled systems for fluorescence and laser-confocal microscopy has provided us with powerful tools to visualize and analyze molecular events in the cells. Various fluorescent staining and labeling techniques have also been developed to be used with these powerful instruments. Fluorescent proteins such as green fluorescent protein (GFP) allow us to directly label particular proteins of interest in living cells. This technique has been extended over a large area of cell biology, and a variety of fluorescent protein-derived techniques have been developed to visualize the functions and conditions of the molecules within living cells. In this review, we summarize the techniques for fluorescent staining and labeling for recent fluorescence microscopy. 相似文献
975.
976.
977.
Shimamura M Huang YY Okamoto N Suzuki N Yasuoka J Morita K Nishiyama A Amano Y Mishina T 《European journal of immunology》2007,37(7):1836-1844
We have demonstrated that analogues of alpha-mannosyl ceramide (alpha-ManCer) consisting of a series of immunosuppressive 2-aminoalcohol derivatives in place of sphingosine promote a greater immune response from mouse invariant Valpha19-Jalpha26 (AV19-AJ33) TCR-bearing NKT (Valpha19 NKT) cells than alpha-ManCer itself. To further characterize the immune responses of Valpha19 NKT cells to the alpha-ManCer analogues, cytokine production by the cells was examined in detail. We found that certain alpha-ManCer derivatives individually induced either Th1- or Th2-dominant cytokine production in culture. The Th1- or Th2-biased immune responses of Valpha19 NKT cells were dependent on MHC class I-like MR1, since they were induced by coculture with the MR1 transfectants previously loaded with the glycolipids and were inhibited in the presence of anti-MR1 antiserum. Presumably, the recognition of the alpha-mannosyl residue of the alpha-ManCer analogues by the invariant TCR is individually modulated, depending on the altered interaction with the groove of the antigen-presenting MR1. Priming of the Valpha19 invariant TCR-transgenic mice in vivo with these glycolipid derivatives resulted in the induction of the Th1- or Th2-biased immune responses. Thus, these alpha-ManCer derivatives are likely to be useful in immunotherapy for either Th1 or Th2 excess autoimmune diseases, modulating the function of Valpha19 NKT cells. 相似文献
978.
Ishida-Okawara A Nagi-Miura N Oharaseki T Takahashi K Okumura A Tachikawa H Kashiwamura S Okamura H Ohno N Okada H Ward PA Suzuki K 《Experimental and molecular pathology》2007,82(2):220-226
We have established a mouse model which shows the symptoms of coronary arteritis after consecutive injections of CAWS, which is released from Candida albicans. In this study, we examined neutrophil activation in the initial period after CAWS injection intraperitoneally. During 10 min to 16 h after the injection, blood profiles and neutrophil functions were determined. At the same time, levels of inflammatory cytokines and chemokines in plasma were measured. Furthermore, level of ICAM-1 as a marker of lesion in arterial endothelial cells was measured. Counts of the peripheral leukocytes increased immediately after CAWS injection, especially involving neutrophil. In vitro sensitivity of neutrophils to stimuli was enhanced. Moreover, proinflammatory cytokines (IL-1beta, IL-12 and IL-6) increased in plasma initially followed by an increase in IL-10, G-CSF, MIP-2 and soluble ICAM-1. Locally, ICAM-1 message in arterial walls was significantly increased 16 h after CAWS injection. A decrease in C3 levels was observed in plasma, suggesting complement activation and consumption. In summary, neutrophil activation occurred after CAWS injection, followed by complement activation, and production of proinflammatory cytokines chemokines and G-CSF which may be involved in development of coronary arteritis. 相似文献
979.
Endocrine disrupting chemicals, 4‐nonylphenol,bisphenol A and butyl benzyl phthalate,impair metabolism of estradiol in male and female rats as assessed by levels of 15α‐hydroxyestrogens and catechol estrogens in urine 下载免费PDF全文
Madoka Nakagomi Emako Suzuki Yoshiaki Saito Tetsuji Nagao 《Journal of applied toxicology : JAT》2018,38(5):688-695
Bisphenol A (BPA), 4‐nonylphenol (NP) and butyl benzyl phthalate (BBP), termed endocrine‐disrupting chemicals, are known to mimic estrogen activity. The effects of these chemicals on 17β‐estradiol (E2) metabolism in vivo in rats were examined. Male and female rats were given NP (250 mg kg–1 day–1), BPA (250 μg kg–1 day–1) or BBP (500 mg kg–1 day–1) by gavage for 14 days, followed by a single intraperitoneal injection of E2 (5 mg kg–1) on the final day. The urinary excretion over 72 hours of 2‐hydroxyestrone 1‐N‐acetylcysteine thioether, 2‐hydroxyestrone 4‐N‐acetylcysteine thioether, 4‐hydroxyestrone 2‐N‐acetylcysteine thioether, 2‐hydroxy‐17β‐estradiol (2‐OHE2), 2‐hydroxyestrone (2‐OHE1), 4‐hydroxy‐17β‐estradiol, 4‐hydroxyestrone, 15α‐hydroxyestriol (E4), 15α‐hydroxy‐17β‐estradiol and 15α‐hydroxyestrone was measured. Increases in urinary excretion of 2‐OHE1 and decreases in E4 were observed in males treated with NP or BBP. Decreases in urinary excretion of 2‐OHE2 and E4 were observed in males treated with BPA. Decreases in urinary excretion of 2‐OHE1 and 2‐OHE2 were observed in females treated with BBP. Normalized liver and weights were increased in both sexes treated with NP or BBP. Histologic observations revealed marked changes in the distal tubules and collecting ducts in the kidneys of rats exposed to NP and BBP, and hypertrophy in the hepatocytes of the centrilobular zone of the liver. No BPA‐related effects on organ weight and on liver or kidney histopathology were found. These results suggest that the 14 day oral dosing of NP and BBP disrupted E2 metabolism, resulting from marked morphological and functional alterations in the liver and kidneys. In addition, BPA could induce metabolic and endocrine disruption. 相似文献
980.
Hiroyuki Shimada Hyuma Makizako Takehiko Doi Hyuntae Park Kota Tsutsumimoto Joe Verghese Takao Suzuki 《Journal of the American Medical Directors Association》2018,19(7):584-591