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1.
Buket Bakan Fatih Oltulu Yeliz Y?ld?r?m Altu? Yava?o?lu Sinan Akg?l Nefise ülkü Karabay Yava?o?lu 《Arhiv za higijenu rada i toksikologiju》2023,74(3):207
The aim of this safety study in mice was to determine in vivo toxicity and biodistribution potential of a single and multiple doses of L-glutamic acid-g-p(HEMA) polymeric nanoparticles as a drug delivery system. The single dose did not cause any lethal effect, and its acute oral LD50 was >2.000 mg/kg body weight (bw). Multiple doses (25, 50, or 100 mg/kg bw) given over 28 days resulted in no significant differences in body and relative organ weights compared to control. These results are supported by biochemical and histological findings. Moreover, nanoparticle exposure did not result in statistically significant differences in micronucleus counts in bone marrow cells compared to control. Nanoparticle distribution was time-dependent, and they reached the organs and even bone marrow by hour 6, as established by ex vivo imaging with the IVIS® spectrum imaging system. In conclusion, L-glutamic acid-g-p(HEMA) polymeric nanoparticles appear biocompatible and have a potential use as a drug delivery system.KEY WORDS: biocompatibility, blood biochemistry, genotoxicity, histology, in vivo toxicity, micronucleus test, polymers 相似文献
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Hashem T. Al-Salman Abdulmonem A. Al-Hussien Ibrahim H. Al-Ahmed 《Neurosciences (Riyadh, Saudi Arabia)》2021,26(1):89
Sprengel deformity is a congenital anomaly arising mainly in the shoulder girdle, associated with elevation of dysplastic scapula. skeletal anomalies, mainly Klippel-Feil syndrome, hemivertebrae, and omovertebral bone may be present along Sprengel anomaly. The omovertebral bone is an abnormal bone that originates from the superomedial edge of the scapula with different insertion points along the posterior cervical spine, seen in about third of the patients with Sprengel anomaly. While cosmetic to functional impairment is a common presentation to the omovertebral bone, cervical myelopathy is a rare presentation. Here, we described our experience, management and follow up of 13-year-old boy presented with cervical myelopathy secondary to the omovertebral bone.Sprengel deformity is a complex anomaly of the shoulder girdle, associated with elevation of dysplastic scapula.1-4 Clinically, it is associated with disfigurement and limitation of shoulder movement. Other skeletal anomalies – mainly, Klippel–Feil syndrome, hemivertebrae, and omovertebral bone may be present.4 The omovertebral bone is an abnormal bone that originates from the superomedial edge of the scapula with different insertion points along the posterior cervical spine, seen in about a third of patients with Sprengel anomaly.2,5 The clinical presentation ranges from cosmetic to functional impairment, while cervical myelopathy is a rare presentation related to omovertebral bone. The management and follow up is less described in the literature contributed to its rare occurance.6 Here, the author described a 13-year- old boy diagnosed with Sprengel deformity presented with myelopathic manifestation, where cervical magnetic resonance imaging (MRI) showed signal cord changes secondary to compression by intraspinal extension of the omovertebral bone. The patient underwent uneventful resection of the abnormal bone, and spinal cord decompression. 相似文献
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肿瘤内微生物群(组)已被证实广泛存在于各类肿瘤内,对肿瘤微环境的形成、调控肿瘤生长均发挥着重要作用,并直接影响药物干预肿瘤的疗效。随着新一代基因测序技术的广泛应用,针对肿瘤内微生物功能和分类的研究日益增温。诸多研究表明不同肿瘤内微生物种属分布不同,且不同种微生物所发挥的促/抑瘤机制不同。针对肿瘤内微生物的编辑技术亦取得了许多成果,有望成为检测与治疗肿瘤的新手段。本文旨在对近年来肿瘤内微生物群(组)相关研究进展加以综述,并展望其应用前景。 相似文献
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J. Funk N. Biber M. Schneider E. Hauser S. Enzenmüller C. F?rtsch H. Barth H. Schmidt 《Infection and immunity》2015,83(6):2338-2349
In this study, the cytotoxicity of the recently described subtilase variant SubAB2-2 of Shiga toxin-producing Escherichia coli was determined and compared to the plasmid-encoded SubAB1 and the chromosome-encoded SubAB2-1 variant. The genes for the respective enzymatic active (A) subunits and binding (B) subunits of the subtilase toxins were amplified and cloned. The recombinant toxin subunits were expressed and purified. Their cytotoxicity on Vero cells was measured for the single A and B subunits, as well as for mixtures of both, to analyze whether hybrids with toxic activity can be identified. The results demonstrated that all three SubAB variants are toxic for Vero cells. However, the values for the 50% cytotoxic dose (CD50) differ for the individual variants. Highest cytotoxicity was shown for SubAB1. Moreover, hybrids of subunits from different subtilase toxins can be obtained which cause substantial cytotoxicity to Vero cells after mixing the A and B subunits prior to application to the cells, which is characteristic for binary toxins. Furthermore, higher concentrations of the enzymatic subunit SubA1 exhibited cytotoxic effects in the absence of the respective B1 subunit. A more detailed investigation in the human HeLa cell line revealed that SubA1 alone induced apoptosis, while the B1 subunit alone did not induce cell death. 相似文献
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Hashem Sezavar Ali-Akbar Saboor-Yaraghi Eisa Salehi 《Immunological investigations》2015,44(2):189-198
Background: The aim of present study is evaluation of vitamin A supplementation efficacy on IFN-? and T-bet gene expression in atherosclerotic patients.Methods: Thirty-one patients and 15 healthy controls participated in this study. Healthy control and patients in Vitamin A group received 25?000?IU retinyl palmitate daily for 4 months. Control patients also received 1 pearl of placebo per day up to 4 months. Gene expression levels were assessed by real-time PCR using SYBR green detection method.Results: IFN-γ gene expression in fresh cells of patients taking vitamin A declined slightly (0.85-fold, p?=?0.068), whereas the expression of this gene was increased in patients taking placebo, and in healthy control subjects 1.2-fold (p?=?0.267) and 1.7-fold (p?=?0.580), respectively. There were no significant difference (p?=?0.159) between 3 groups in terms of IFN-γ gene expression in cells stimulated with PHA. In order to determine whether PHA stimulation of PBMCs in vitro had an effect on T-bet expression, we measured the difference between the 3 groups of studied. The results showed significant differences between the groups (p?=?0.046). IFN-γ gene expression in cells activated with ox-LDL in healthy control subjects and patients taking vitamin A, was reduced 0.43 (p?=?0.0001) and 0.41 (p?=?0.001) respectively, but in placebo patients was increased 2.2-fold (p?=?0.959).Conclusion: Considering role of vitamin A on suppression of Th1 cells in atherosclerotic patients, it can be concluded that vitamin A supplementation may be advantageous for these patients. 相似文献
10.
After 4 years of early benefit assessment (EBA) in Germany, it is becoming evident that the Federal Joint Committee (FJC) frequently considers well-established clinical endpoints as not being relevant to patients. Focusing on assessments of oncology medicines, we analysed the FJC’s view on primary endpoints and compared it with the approach used by regulatory authorities. Mortality data were accepted by both stakeholders. Whereas regulatory authorities accepted primary morbidity endpoints such as progression-free survival and response rates, the FJC mostly excluded these from its assessments. Health-related quality of life (HRQoL) data have been poorly reflected in the approval process; for EBAs, those data have rarely impacted on benefit ratings. We argue that agreement between regulatory authorities and the FJC is required regarding primary study endpoints that are relevant to patients, and that clarification of acceptable endpoints by the FJC, especially in the morbidity domain, has to be provided. Moreover, in order to fully acknowledge the benefit of a new medicinal product, mortality, morbidity and HRQoL should be weighted differentially, according to the condition. 相似文献