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1.
Radiodermatitis is one of the commonest side effects of radiotherapy. They are usually assessed by semi‐quantitative clinical scores, which are not validated and may be subject to inter‐observer variability. A few previous studies suggested that high‐frequency ultrasonography (HF‐USG) is useful in the assessment of the acute phase of radiation dermatitis in breast cancer patients. (a) To monitor skin changes by HF‐USG during the course of radiotherapy due to head and neck cancers, and (b) to determine whether there is any connection between skin sonograms and the skin scoring criteria. This prospective, observational study includes patients diagnosed with head and neck cancers, treated with radiotherapy or concomitant chemoradiation. The final analysis includes six patients. In every patient, the HF‐USG as well as dermatological assessment (target lesion score—TLS and CACE v. 4.0) were performed 4×: before, in the middle, day after, and 3 months after radiotherapy. There were significant differences between non‐irradiated skin thickness and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P < .0001), as well as between irradiated, unchanged skin thickness (TLS grade 0) and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P = .0002). There was no significant difference between non‐irradiated and irradiated, unchanged skin thickness (TLS grade 0; P = .9318). In four patients, we demonstrated subepidermal low echogenic band (SLEB). HF‐USG can be useful tool to noninvasive and objective assessment of skin changes during radiotherapy.  相似文献   
2.
Variation in opinions of medical experts is a problem for both the legal and medical profession. This is particularly relevant in breast imaging. BreastScreen Queensland and New South Wales have developed a review protocol to assess ‘reasonableness’ of radiological opinions. It is hoped that the protocol will be acceptable to the courts and will result in a fair outcome for all parties involved in a medico-legal dispute.  相似文献   
3.
The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells.  相似文献   
4.
大肠重复癌MMR、p53、Bax、PCNA表达及微卫星不稳定性研究   总被引:3,自引:0,他引:3  
目的探讨微卫星不稳定性 (MSI)在大肠重复癌与单发癌中的变化规律 ,及MMR、p5 3、Bax、PCNA表达与MSI的关系。 方法采用免疫组化、PCR SSLP法对 38例大肠重复癌患者的 5 1处癌灶及 35例单发大肠癌分别进行MMR、p5 3、Bax、PCNA表达的检测和 5个微卫星位点MSI检测。结果重复癌组复制错误阳性率为 5 3% (2 7/ 5 1) ,单发癌组为 17% (6 / 35 ) ,差异有显著性意义 (χ2 =11 2 5 ,P <0 0 1)。重复癌组中 ,RER 与MMR表达缺失有密切的相关性 ;RER 与 p5 3表达呈负相关 ;RER 组PCNA标记指数显著低于RER-组 ;RER 与低分化、近端大肠癌密切相关。结论MSI在大肠重复癌的发生上起着重要作用 ,MSI可作为预测大肠重复癌发生的重要标志。  相似文献   
5.
In ongoing reviews of 339 patients with surgically treated primary squamous cell carcinoma, there were 19 (5.6%) with concurrent gastric cancer and 11 (3.2%) with head and neck cancer. The incidences of intra-esophageal multiple occurrence of esophageal cancer are 27.3% and 26.3% in those with associated head and neck cancer and gastric cancer, respectively, and higher than 7.1% in those without such a concurrent cancer. There was no difference in the clinicopathological characteristics of those with concurrent head and neck and gastric cancers, except for the higher incidence of metachronous occurrence in the former. These findings suggest that, in cases of esophageal cancer associated with concurrent head and neck cancer and gastric cancer, intraesophageal multiplicity of the esophageal carcinoma is frequent and that preoperative serial evaluations is most important to design treatment and estimate the prognosis.  相似文献   
6.
目的探讨定量测定肝癌患者血清12种肿瘤标志物的临床意义。方法用蛋白芯片技术定量测定42例正常人、46例肝癌、41例肝炎和23例肝硬化患者血清12种肿瘤标志物的变化并对检测效果进行评价。结果42例正常人CA-199(KU/L)、NSE(g/L)、CEA(g/L)、CA-242(KU/L)、Ferritin(g/L)、β-HCG(g/L)、AFP(g/L)、f-PSA(g/L)、PSA(g/L)、CA-125(KU/L)、HGH(g/L)和CA-153(KU/L)的含量分别为12.42±10.62、2.22±1.43、1.28±1.20、5.72±5.73、91.17±79.43、0.64±0.34、2.96±3.93、0.13±0.11、0.61±1.40、5.46±9.65、1.61±2.40、9.83±9.51;46例肝癌患者血清12种肿瘤标志物含量依次为:35.09±39.50、2.83±4.13、2.98±8.72、8.47±23.42、157.50±129.77、0.72±0.72、87.58±63.27、0.15±0.19、0.58±1.88、56.34±102.02、3.63±4.57、15.65±51.09;41例肝炎患者其含量依次为:76.23±96.57、4.12±4.94、2.06±3.92、4.68±6.99、298.76±326.82、1.00±0.74、63.16±91.76、0.11±0.006、0.27±0.94、18.57±36.60、3.63±4.00、6.13±6.86;23例肝硬化患者其含量依次为:49.85±75.60、5.47±14.97、1.71±1.77、12.44±34.55、278.32±326.82、0.70±0.54、52.89±98.28、0.22±0.21、2.24±4.36、111.50±191.99、2.15±0.99、10.51±15.79。该蛋白芯片测定的敏感性为50.0%,特异性为64.2%,阳性预测值为37.7%,阴性预测值为74.7%。结论采用蛋白芯片技术同时测定患者血清多种肿瘤标志物,对普查肿瘤和临床疗效观察有较好应用价值。  相似文献   
7.
长期生存癌症患者的述情障碍   总被引:8,自引:1,他引:8  
目的:探讨长期生存癌症患者的述情障碍及其相关因素,方法:采用多伦多述情障碍量表及症状自评量表,对36例长期生存癌存患者测评,并与45例正常人进行对照比较,结果:(1)癌症组与对照组在SCL-90评价中无显著性差异(P>0.05)。(2)癌症组TAS总分值明显高于对照组,其中以Ⅱ、Ⅲ、Ⅳ因子尤为明显(P<0.05-0.01)。(3)Ⅰ因子与躯体化、焦虑、恐怖焦虑及精神病症呈显著性正相关(P<0.05)。Ⅲ因子与强迫性,人际关系敏感,敌意及精神病症呈显著性负相关(P<0.05)。Ⅳ因子与偏执化呈显著性负相关(P<0.05)。结论:长期生存癌症患者虽然SCL-90测评可正常,但存在较明显的述情障碍。  相似文献   
8.
Heritability and molecular genetic studies of endometriosis   总被引:22,自引:0,他引:22  
Endometriosis is a common disease defined as the growth of endometrial tissue outside the uterine cavity that often results in a vast array of gynaecological problems including dyspareunia, dysmenorrhoea, pelvic pain and infertility. Despite the increasing evidence that supports a genetic component to this common gynaecological condition, the basic aetiology and pathogenesis of endometriosis remain unknown. It is likely that endometriosis is a common polygenic/multifactorial disease caused by an interaction between multiple genes as well as the environment. Such conditions do not have a clear Mendelian pattern of inheritance. Recent molecular cytogenetic studies on endometriotic tissue and an established endometriosis-derived cell line provide novel evidence that acquired chromosome-specific alterations may be involved in endometriosis, possibly reflecting clonal expansion of chromosomally abnormal cells. Molecular DNA studies examining the role of loss of heterozygosity in endometriotic lesions has identified candidate tumour suppressor gene loci, including 5q, 6q, 9p, 11q and 22q, that may play a role in the malignant transformation of endometriotic implants to endometrioid ovarian cancers. Evidence of mutations in the tumour suppressor PTEN gene in the endometrioid subtype of epithelial ovarian cancer further suggests that somatic genetic alterations represent early events in the transformation of benign endometriotic cells. Genetic factors are also likely to influence individual susceptibility to endometriosis. There is now evidence that heritable allelic differences in drug-metabolizing enzymes play an important role in the development of endometriosis. Further studies are warranted to identify major susceptibility gene(s) and the mechanism involved in endometriosis to assist in the development of better methods for early detection, diagnosis and prevention.  相似文献   
9.
Despite magnesium (Mg2+) representing the second most abundant cation in the cell, its role in cellular physiology and pathology is far from being elucidated. Mg2+ homeostasis is regulated by Mg2+ transporters including Mitochondrial RNA Splicing Protein 2 (MRS2), Transient Receptor Potential Cation Channel Subfamily M, Member 6/7 (TRPM6/7), Magnesium Transporter 1 (MAGT1), Solute Carrier Family 41 Member 1 (SCL41A1), and Cyclin and CBS Domain Divalent Metal Cation Transport Mediator (CNNM) proteins. Recent data show that Mg2+ transporters may regulate several cancer cell hallmarks. In this review, we describe the expression of Mg2+ transporters in digestive cancers, the most common and deadliest malignancies worldwide. Moreover, Mg2+ transporters’ expression, correlation and impact on patient overall and disease-free survival is analyzed using Genotype Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) datasets. Finally, we discuss the role of these Mg2+ transporters in the regulation of cancer cell fates and oncogenic signaling pathways.  相似文献   
10.
Radical neck dissection is a standard procedure carried out for the teatment of palpable nodes in the neck but if carried out electively in cases where there are no palpable nodes in the neck it is considered to be an overtreatment with its associated morbity. Lateral neck dissection was carried out on twenty patients who had T31 T4 lesion of the larynx and hypophar-vnx with NO neck. The dissection entails removal of Level II. III and IV nodes. Occult metastasis 80% and 85% respectively. The mean follow up was 13 monts. It appears from our study that elective lateral neck dissection is a promising and safe procedure and may be useful as an important prognostic tool in sampling the lymph nodes and predicting recurrences in the neck.  相似文献   
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