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31.
A new algorithmic-based digital filter processing system for real-time continuous blood pressure (BP) measurement and analysis in freely-moving conscious rats has been developed. Real-time recognition of BP waveforms, real-time noise rejection and determination of representative waveform indexes (WIs) at indicated time points using digital filters and Smirnov's rejection test were realized with this system. Digital filters were applied for two different purposes: waveform segmentation and smoothing the calculations of representative WIs. Smirnov's rejection test was used for real-time noise rejection and yielded an accurate rejection rate of 99.99%. The result was that the digital filter processing and Smirnov's rejection test realized accurate real-time BP measurement and analysis in freely-moving conscious rats using a personal computer. 相似文献
32.
Yoshioka S Fujiwara H Higuchi T Yamada S Maeda M Fujii S 《Molecular human reproduction》2003,9(6):311-319
Melanoma cell adhesion molecule (MCAM) was originally reported to be involved in the invasion and progression of melanoma. It was also shown to be responsible for the attachment of cells to endothelial cells. In this study, we demonstrated by immunohistochemistry that immunoreactive MCAM was not expressed on granulosa cells in the pre-ovulatory follicle, but it was clearly detected in large luteal cells in corpora lutea from the mid-luteal phase of the menstrual cycle. Northern blotting analysis confirmed the expression of MCAM mRNA in corpus luteum. MCAM was weakly detected by immunocytochemical staining in human luteinizing granulosa cells isolated from patients undergoing IVF treatment. Its expression was found to be increased during time in culture of these cells. Flow cytometry and Northern blot analysis revealed that MCAM expression on luteinizing granulosa cells was enhanced when the cells were cultured for 5 days in the presence of hCG (1 IU/ml) or cytokines such as interleukin-1alpha (10 ng/ml) and tumour necrosis factor-alpha (10 ng/ml). No significant difference of MCAM expression was observed between the cultures under normoxic (20% oxygen) and hypoxic (1% oxygen) conditions. These results indicate that luteinizing granulosa cells express MCAM and that MCAM expression is regulated by LH/hCG and cytokines during luteinization. Since MCAM has been reported to mediate cellular interaction with endothelial cells, this molecule may play a role in neovascularization during corpus luteum formation in the human ovary. 相似文献
33.
Konno A Hoshino Y Terashima S Motoki R Kawaguchi T 《Clinical & experimental metastasis》2002,19(1):61-70
Carbohydrate expression of cancer cells is closely related to the metastatic nature of colorectal cancer. In the present study we investigated the relevance of carbohydrate expression profiles of colorectal cancer cells in the primary lesion to metastatic distribution patterns as well as prognosis in 134 cases. Carbohydrate expression was estimated by histochemistry with 17 kinds of lectins and 3 kinds of Lewis-related monoclonal antibodies (MAbs), and correlations between the staining and clinicopathological parameters were examined. The results showed that lymphatic invasion, lymph node metastasis, and peritoneal metastasis correlated with staining with lectins that bind galactose/N-acetylgalactosamine residues (Gal/GalNAc) such as Maclura pomifera (MPA), Arachis hypogaea (PNA), Helix pomatia (HPA), and Vicia villosa (VVA). In contrast, hepatic metastasis correlated with staining with Anguilla anguilla lectin (AAA), anti-LewisX (LEX-2), anti-sialyl Lewisa (NS19-9), and anti-sialyl-dimeric LewisX (FH-6) MAbs, all of which bind preferentially to fucosylated carbohydrate chains. The five-year survival rate of patients was related to the staining of cancers with MPA, HPA, FH-6 or NS19-9, and MPA- and FH-6 staining were independent prognostic factors. We conclude that carbohydrate expression profiles of cancer cells are relevant to the route of tumor cell dissemination, metastatic pattern as well as prognosis of colorectal cancer. 相似文献
34.
Sehata S Maejima T Watanabe M Ogata S Makino T Tanaka K Manabe S Takaoka M 《Toxicologic pathology》2002,30(3):328-338
The carcinogenic potential of chloroform was evaluated in a short-term carcinogenicity testing system using CB6F1 rasH2-Tg (rasH2-Tg) mice. Chloroform was administered to rasH2-Tg males at doses of 28, 90, or 140 mg/kg and rasH2-Tg females at 24, 90, or 240 mg/kg by oral gavage for 26 weeks. Wild-type (non-Tg) male and female mice received doses of 140 mg/kg and 240 mg/kg, respectively. N-methyl-N-nitrosourea was administered to rasH2-Tg mice by single intraperitoneal injection (75 mg/kg) as a positive control. In both the rasH2-Tg and non-Tg mice, there was no significant increase in the incidence of neoplastic lesions by chloroform treatment. The incidence of hepatocellular foci in the rasH2- and non-Tg females receiving 240 mg/kg was increased. Forestomach tumors and malignant tumors occurred in most of the rasH2-mice in the positive control group. Swelling or vacuolation of hepatocytes, a toxic change induced by chloroform, occurred in both the rasH2-Tg and non-Tg mice. It is concluded that chloroform, a putative human noncarcinogen, did not show evidence of carcinogenic potential in the present study using rasH2-Tg mice. This study suggests that the rasH2-Tg mouse model may not be appropriate for detecting nongenotoxic carcinogens. However, the sensitivity of rasH2-Tg mice to nongenotoxic carcinogens should be assessed with consideration of the results from the other ILSI-HESI project studies. 相似文献
35.
Masuda S Sakagami T Hirota S 《Shinrigaku kenkyu : The Japanese journal of psychology》2002,73(1):34-41
Ellsberg's two-color problem, known as an example of ambiguity aversion, has generated a great deal of interest among many researchers. However, an unsettled question remains regarding the conditions that lead to heightened or diminished ambiguity aversion. We conducted a series of experiments, which required participants to choose between a clear and vague bet. Results showed that participants did not always prefer the clear bet, and the ratios of those who indicated ambiguity aversion varied depending on the types of ambiguity. Furthermore, ambiguity aversion consistently decreased when participants were allowed to choose the ambiguity task they would perform. These results were interpreted in terms of the pattern of second order probability distributions and illusion of control. 相似文献
36.
Seiko Iwata Yukiko Shibata Jun-ichi Kawada Shinya Hara Yukihiro Nishiyama Tsuneo Morishima Masaru Ihira Tetsushi Yoshikawa Yoshizo Asano Hiroshi Kimura 《Journal of clinical virology》2006,37(2):128-133
BACKGROUND: The loop-mediated isothermal amplification (LAMP) method is a novel technique for the amplification of specific DNA sequences. OBJECTIVES: To establish the LAMP method for amplifying Epstein-Barr virus (EBV) DNA and to examine its reliability for the detection of EBV DNA in clinical specimens. STUDY DESIGN: Sera from 108 patients, who were initially suspected of primary EBV infection, were tested by the EBV LAMP method, and the results were compared with those of the real-time PCR assay. Serological examination was regarded as the standard diagnostic method. RESULTS: To diagnose primary EBV infection, the sensitivity of LAMP was 86.4% and the specificity was 100%. The sensitivity of the real-time PCR assay was 84.1% and the specificity was 98.4%. Longitudinal analysis showed that the detection rate of EBV DNA in serum by the LAMP method decreased with time in accordance with the decrease of the EBV load. EBV DNA could not be detected in serum 40 days after onset of symptoms. CONCLUSIONS: These results indicate that the sensitivity and specificity of the LAMP method are comparable to those of real-time PCR and that detecting EBV DNA in serum by this method is potentially useful for diagnosing primary EBV infection. 相似文献
37.
Yamashita H Noguchi Y Noguchi S Yamashita H Uchino S Watanabe S Ogawa T Murakami T 《Endocrine pathology》2005,16(1):41-48
Risk factors for distant metastasis were studied in 82 patients with follicular thyroid carcinoma (FTC). Metastases to either
the lung or bone existing at the time of presentation were confirmed by I-131 radio-iodine uptake in 10 patients. FTC with
an insular component was found in eight patients. Univariate analysis of 14 possible risk factors showed 7 to be statistically
significant: insular component, poorly differentiated carcinoma, trabecular component, serum thyroglobulin level before surgery,
patient age at the time of presentation, solid component, and vascular invasion (ranked by p values). After further analysis of the interrelation of the factors and of the logistic regression curves, we concluded that
presence of an insular component and patient age were the only independent risk factors. Distant metastasis was not detected
in any of the 27 patients ≤49 yr old. Among the 55 older patients (≥50 yr old), 5 of the 49 (10%) without an insular component
and 5 of the 6 (83%) with an insular component had distant metastasis. The remaining older patient with an insular component
but without distant metastasis showed a gradual increase in thyroglobulin levels after total thyroidectomy. 相似文献
38.
Fukumoto S Tamaki Y Shirafuji H Harakawa S Suzuki H Xuan X 《Clinical and diagnostic laboratory immunology》2005,12(4):557-559
This is a report of a vaccine trial directed against Babesia gibsoni infection in dogs with the use of the recombinant antigen P50. Dogs immunized with P50 showed partial protection manifested as a significantly low level of parasitemia. The results indicated that P50 is a primary vaccine candidate molecule against canine B. gibsoni infection. 相似文献
39.
Immunohistochemical analysis of MCT1, MCT2 and MCT4 expression in rat plantaris muscle 总被引:3,自引:1,他引:3
Takeshi Hashimoto Shinya Masuda Sadayoshi Taguchi George A. Brooks 《The Journal of physiology》2005,567(1):121-129
All three forms of recombinant low voltage-activated T-type Ca2 + channels (Cav 3.1, Cav 3.2 and Cav 3.3) exhibit a small, though clearly evident, window T-type Ca2 + current ( I Twindow ) which is also present in native channels from different neuronal types. In thalamocortical (TC) and nucleus reticularis thalami (NRT) neurones, and possibly in neocortical cells, an I Twindow -mediated bistability is the key cellular mechanism underlying the expression of the slow (< 1 Hz) sleep oscillation, one of the fundamental EEG rhythms of non-REM sleep. As the I Twindow -mediated bistability may also represent one of the cellular mechanisms underlying the expression of high frequency burst firing in awake conditions, I Twindow is of critical importance in neuronal population dynamics associated with different behavioural states. 相似文献
40.