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A 5' nuclease TaqMan PCR was developed for the quantitative detection of the periodontopathic bacteria Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. The relative numbers of bacteria were measured by the comparative threshold cycle method. This simplified method is a way of obtaining the relative quantities of these organisms from specimens and of monitoring the effect of therapy.  相似文献   
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Camostat mesilate (CM), an oral protease inhibitor, has been used clinically for the treatment of chronic pancreatitis in Japan. However, the mechanism by which it operates has not been fully understood. Our aim was to evaluate the therapeutic efficacy of CM in the experimental pancreatic fibrosis model induced by dibutyltin dichloride (DBTC), and we also determined the effect of CM on isolated monocytes and panceatic stellate cells (PSCs). In vivo, chronic pancreatitis was induced in male Lewis rats by single administration of 7 mg/kg DBTC and a special diet containing 1 mg/g CM was fed to the DBTC+CM-treated group from day 7, while the DBTC-treated group rats were fed a standard diet. At days 0, 7, 14 and 28, the severity of pancreatitis and fibrosis was examined histologically and enzymologically in both groups. In vitro, monocytes were isolated from the spleen of a Lewis rat, and activated with lipopolysaccharide stimulation. Thereafter, the effect of CM on monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-alpha (TNF-alpha) production from monocytes was examined. Subsequently, cultured rat PSCs were exposed to CM and tested to see whether their proliferation, MCP-1 production and procollagen alpha1 messenger RNA expression was influenced by CM. In vivo, the oral administration of CM inhibited inflammation, cytokines expression and fibrosis in the pancreas. The in vitro study revealed that CM inhibited both MCP-1 and TNF-alpha production from monocytes, and proliferation and MCP-1 production from PSCs. However, procollagen alpha1 expression in PSCs was not influenced by CM. These results suggest that CM attenuated DBTC-induced rat pancreatic fibrosis via inhibition of monocytes and PSCs activity.  相似文献   
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Medaka fish (Oryzias latipes) were exposed to various doses of X-rays or fast neutrons, and the frequency of micronucleated cells (MNCs) was measured in gills sampled at 12- or 24-hr intervals from 12 to 96 hr after exposure. The resulting time course of MNC frequency was biphasic, with a clear peak 24 hr after exposure, irrespective of the kind of radiation applied and the dose used. The half-life of MNCs induced in the gill tissues by the two exposures fluctuated around 28 hr, with no significant dose-dependent trend for either X-ray- or neutron-exposed fish. As assayed 24 hr after exposure, the MNC frequency increased linearly over the control level with increasing doses of both X-rays and fast neutrons. The relative biological effectiveness (RBE) of fast neutrons to X-rays for MNC induction was estimated to be 4.3 +/- 0.6. This value is close to the RBE value of 5.1 +/- 0.3 reported for fast neutron induction of somatic crossing-over mutations in Drosophila melanogaster that arise from recombination repair of DNA double-strand breaks. These results and other data support our conclusion that the medaka gill cell micronucleus assay is a reliable short-term test for detecting potential inducers of DNA double-strand breaks.  相似文献   
5.
Genomic subtractive hybridization was used to design Prevotella nigrescens-specific primers and TaqMan probes. Based on this technique, a TaqMan real-time PCR assay was developed for quantifying four oral black-pigmented Prevotella species. The combination of real-time PCR and genomic subtractive hybridization is useful for preparing species-specific primer-probe sets for closely related species.  相似文献   
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卵巢癌腹膜后淋巴结转移的特点及其临床意义   总被引:1,自引:0,他引:1  
目的:研究卵巢上皮性癌淋巴结转移的解剖学和生物学特点及临床合理治疗。方法:40例Ⅰ期卵巢癌根据清除淋巴结与否分成A、B两组;40例Ⅲ-Ⅳ卵巢癌清除淋巴结20例为C组、不清除淋巴结20例为D组,C、D两组减瘤术后残余癌灶均2cm。化疗方法,药物及其剂量基本相同。结果:A组3例腹主动脉旁淋巴结转移者合并盆腔淋巴结转移2例,单纯盆腔淋巴结转移1者,共4例淋巴结转移,转移率20%。A、B两组5年生存率各为95%与80%。C组腹主动脉旁淋巴结转移10例中合并盆腔淋巴结转移9例,单独盆腔淋巴结转移2例,转移率为60%(12/20)。C、D两组5年生存率各为55%与15%。5年生存率A、B两组差异有显著意义(P〈0.05),C、D两组差异有极显著意义(P〈0.001)。结论:卵巢癌淋巴结转移率,随期别而升高,腹主动脉旁与盆腔淋巴结转移率几乎相等,但腹主动脉旁淋巴结转移是主要路线。恰当清除淋巴结可以提高生存率。  相似文献   
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The calpains, a family of calcium-dependent cysteine proteinases, and calpastatin, their endogenous inhibitor protein, are involved in the proteolysis of amyloid precursor protein, which is thought to be abnormal in patients with Alzheimer's disease (AD). Specific inhibitors of calpains attenuate amyloid beta peptide-induced neuronal death. We hypothesized that some AD patients have functionally deficient mutation(s) of the CAST gene encoding calpastatin, and we screened 40 Japanese patients with AD for mutations in the coding region of CAST. Nine polymorphisms, -82A/G, IVS7-96A/G, 669A/G, 1223C/G (Ser408Cys), IVS20-10C/T, IVS21-65G/A, IVS22+31T/C, IVS24+38Ins/DelA, and IVS25-32A/G, were identified. The 669A allele causes skipping of exon 11, leading to the loss of 13 residues. Comparisons between 101 patients and 90 controls revealed no significant association between CAST polymorphisms and risk for AD, indicating that genomic variations of CAST are not likely to be substantially involved in the etiology of AD.  相似文献   
9.
Background/Objective: The feces sign has been reported as a possible predictive factor for non-operative treatment of small bowel obstruction. However, its relationship with prognosis of non-emergency adhesive small bowel obstruction remains unclear. This study aimed to clarify the relationship between the feces sign and prognosis of non-emergency adhesive small bowel obstruction.MethodsNinety-two patients with non-emergency adhesive small bowel obstruction with the transitional zone visible on computed tomography were included. Patients were categorized into two groups: feces sign positive (n = 40) and negative (n = 52). Clinical features and prognosis were compared between the two groups. Cox proportional hazards regression models incorporating the feces sign were used to analyze odds of diet resumption and discharge.ResultsPatients with feces sign were younger (p = 0.015), had a higher body mass index (p = 0.027), and a lower white blood cell count (p = 0.019) on admission. More patients with feces sign were successfully treated with fasting and/or nasogastric tube placement (p < 0.001), and no patient with feces sign suffered from recurrent obstruction after diet resumption. Kaplan–Meier analysis showed that patients with feces sign took less time for diet resumption (p = 0.007) and discharge (p = 0.004) than those without it. Using Cox proportional hazards regression model, the feces sign was reported as an independent predictor of diet resumption (odds ratio 1.685, p = 0.018) and discharge (odds ratio 1.861, p = 0.007).ConclusionsThe feces sign is associated with improved odds for diet resumption and discharge.  相似文献   
10.
针对髋臼前后柱置钉通道多截面调控规划法的不足,该研究提出了基于大密度点云数据、相关理论、软件内置功能及自编程序的规划方法,实现了对置钉通道总长的全局优化,同时进行了基于7截面、11截面调控规划法以及点云数据的前柱最大内接圆柱体虚拟置钉实验,分析了实验结果及形成机理,验证了基于点云数据规划法的全局优化效果,但对多截面调控规划法的调控有效性表示还存有疑问,此外,还对基于点云数据的髋臼置钉通道规划方法应用的相关原理和操作技巧作了简略介绍。  相似文献   
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