首页 | 官方网站   微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   205984篇
  免费   28651篇
  国内免费   7100篇
医药卫生   241735篇
  2024年   484篇
  2023年   4283篇
  2022年   7018篇
  2021年   11292篇
  2020年   10579篇
  2019年   9549篇
  2018年   9186篇
  2017年   9604篇
  2016年   10331篇
  2015年   11968篇
  2014年   17148篇
  2013年   16896篇
  2012年   13641篇
  2011年   13791篇
  2010年   10013篇
  2009年   10215篇
  2008年   10515篇
  2007年   9868篇
  2006年   8700篇
  2005年   7101篇
  2004年   5922篇
  2003年   4911篇
  2002年   4160篇
  2001年   3836篇
  2000年   3178篇
  1999年   2680篇
  1998年   2234篇
  1997年   1986篇
  1996年   1601篇
  1995年   1491篇
  1994年   1219篇
  1993年   935篇
  1992年   804篇
  1991年   740篇
  1990年   541篇
  1989年   496篇
  1988年   417篇
  1987年   366篇
  1986年   280篇
  1985年   361篇
  1984年   297篇
  1983年   197篇
  1982年   205篇
  1981年   188篇
  1980年   168篇
  1979年   108篇
  1978年   70篇
  1977年   57篇
  1976年   51篇
  1975年   31篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
101.
HER2-positive (HER2+) breast cancer (BC) is a heterogenous and multifaceted disease, with interesting therapeutic implications. First, all intrinsic molecular subtypes can be identified in HER2+ tumors, with the HER2-enriched being the most frequent. Such subtypes do not differ much from their counterparts in HER2-negative disease, apart for the high expression of genes in/near the HER2 amplicon on chromosome 17. Intrinsic subtyping, along with the quantification of ERBB2 mRNA levels, is associated with higher rates of pathologic complete response across neoadjuvant trials of dual HER2 blockade and might help select patients for de-escalation and escalation treatment strategies. Secondly, HER2+ tumors have a broad range of DNA alterations. ERBB2 mutations and alterations in the PI3K/Akt/mTOR pathway are among the most frequent and might predict benefit from potent pan-HER, PI3K and mTOR inhibitors. Moreover, HER2+ tumors are usually infiltrated by lymphocytes. These tumor infiltrating-lymphocytes (TILs) predict response to neoadjuvant anti-HER2-based treatment and exert a prognostic role. PD-L1, detected in ∼42 % of HER2+ BC, might also be useful to define patients responding to novel anti-PD1/PD-L1 immunotherapies. New multiparametric clinicopathologic and genomic tools accounting for this complexity, such as HER2DX, are under development to define more tailored treatment approaches. Finally, HER2-targeted antibody-drug conjugates (ADC) such as trastuzumab deruxtecan might be active in tumors with low expression of HER2. Overall, there is a need to molecularly characterize and develop novel targeted therapies for HER2+ disease.  相似文献   
102.
103.
ObjectiveThis study used a prospective cohort study to observe the effect of triple-negative breast cancer on the 2-year disease-free survival rate with or without “TCM formula”.MethodsFrom November 1 st, 2016, the first patient was enrolled in the cohort study. A total of 356 patients were enrolled on January 30, 2019. Among them, 154 cases were followed up for 2 years. During the follow-up, there were 6 cases of shedding, so 6 cases were affected. A total of 148 cases were included in the analysis, including 73 in the exposed group and 75 in the non-exposed group. The exposed group was given “TCM formula” on the basis of standardized treatment, and the non-exposed group was treated with simple triple-negative breast cancer. The two groups visited each of the three months. The interview included safety examination (hematology and imaging). The endpoint was the difference in 2-year invasive disease-free survival between the exposed and non-exposed groups and the safety of the “TCM formula”.ResultsThere were 6 cases of shedding during the experiment and the shedding rate was 3.9 %. The 2-year rate of invasive disease-free survival in the exposed team was 88.7 % and the non-exposed group was 82.5 %. Logistic multivariate regression analysis predicted that “TCM formula” could reduce the disease-related recurrence and metastasis rate by 11 % (OR = 0.89, 95 % CI 0.37−0.956, P<0.05). Through K–M survival analysis, TNBC patients with age ≤35 years and regional lymph node stage N1 may be the benefit group of “TCM formula”(P<0.05). During the study, the incidence of total adverse events was 8.2 % in the exposed group, mainly manifested as stomach discomfort, diarrhea, and hepatocyte damage.Conclusion1. In the exposed group, the two-year rate of invasive disease-free survival increased by 6.2 % compared with the non-exposed group(P>0.05). 2. According to K–M survival analysis, TNBC patients with age ≤35 years and regional lymph node metastasis to N1 may be potential beneficiaries of “TCM formula”. 3. “TCM Formula” is safe and tolerable to most patients.  相似文献   
104.
The serrated pathway (SP) can be viewed as two parallel, but partially overlapping, arrays of colorectal precursor lesions, and their respective endpoint carcinomas, that are distinct from those of the conventional adenoma–carcinoma sequence (APC‐pathway). In this review we focus at the outset on the clinical impact, pathological features, molecular genetics and biological behaviours of the various SP cancers. Then we summarize the clinicopathological features, classification and molecular profiles of the two main precursor lesions that anchor the respective pathways: (i) sessile serrated adenoma/polyp (SSA/P), also called sessile serrated lesion (SSL), and (ii) traditional serrated adenoma (TSA). Activating mutations of the RAS–RAF–MAPK pathway initiate and sustain the lesions of the SP, and CpG island methylation of the promoter regions of tumour suppressor and DNA repair genes play the major role in their neoplastic progression. The SP includes microsatellite stable (MSS) carcinomas that are among the most biologically aggressive colorectal carcinomas (CRC), and also accounts for the great preponderance of sporadic hypermutated, mismatch repair (MMR)‐deficient or microsatellite instable (MSI) CRC. The identification, removal and appropriate classification of at‐risk SP precursors and surveillance of individuals who harbour these lesions present a challenge and opportunity for CRC prevention and mortality reduction.  相似文献   
105.
丝氨酸生物合成途径活性的上调是许多癌症明显的共同特征。该途径的第一种限速酶3-磷酸甘油酸脱氢酶(PHGDH)在黑色素瘤、乳腺癌和肾癌等癌组织中高表达,对肿瘤细胞增殖、转移、侵袭有着重要作用。糖酵解中间产物3-磷酸甘油酸在PHGDH作用下,氧化为磷酸羟基丙酮酸并最终合成丝氨酸。丝氨酸转化为甘氨酸,然后在核苷酸、s-腺苷甲硫氨酸(SAM)和还原型谷胱甘肽(GSH)的合成中起着重要的作用。PHGDH 有望成为肿瘤治疗的新靶点。  相似文献   
106.
《Urologic oncology》2015,33(5):217-225
Although both surgery and radiation are potential curative options for men with clinically localized prostate cancer, a significant proportion of men with high-risk and locally advanced disease will demonstrate biochemical and potentially clinical progression of their disease. Neoadjuvant systemic therapy before radical prostatectomy (RP) is a logical strategy to improve treatment outcomes for men with clinically localized high-risk prostate cancer. Furthermore, delivery of chemotherapy and other systemic agents before RP affords an opportunity to explore the efficacy of these agents with pathologic end points.Neoadjuvant chemotherapy, primarily with docetaxel (with or without androgen deprivation therapy), has demonstrated feasibility and safety in men undergoing RP, but no study to date has established the efficacy of neoadjuvant chemotherapy or neoadjuvant chemohormonal therapies. Other novel agents, such as those targeting the vascular endothelial growth factor receptor, epidermal growth factor receptor, platelet-derived growth factor receptor, clusterin, and immunomodulatory therapeutics, are currently under investigation.  相似文献   
107.
The objectives of this study were to evaluate survival in 141 patients with stage II–IV oral squamous cell carcinoma (OSCC) treated with preoperative intra-arterial chemotherapy with docetaxel, cisplatin, and peplomycin combined with intravenous chemotherapy using 5-fluorouracil (IADCPIVF) via the superficial temporal artery, and to clarify the prognostic factors. The study population included 59 patients with stage II OSCC, 34 with stage III, and 48 with stage IV. After IADCPIVF, 139 patients underwent surgery; minimally invasive surgeries (MIS) including excisional biopsy were performed on 96 patients with a remarkably good response to IADCPIVF. The primary tumour response rate was 99.3% (complete response rate 56.7%, good partial response rate 17.0%, fair partial response rate 25.5%). Additionally, there were no serious adverse events associated with IADCPIVF. The 5-year overall survival rate was 74.6% (stage II 83.6%, stage III 72.7%, stage IV 64.8%). In the multivariate analysis of survival, T classification and clinical tumour response were significant prognostic factors. Eight (8.3%) of the patients who received MIS had primary recurrence and six were salvaged. In conclusion, IADCPIVF is safe and efficacious for treating OSCC, and MIS could reduce the extent of primary tumour resection in the case of a remarkably good response.  相似文献   
108.
Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them.  相似文献   
109.
目的 对促甲状腺素(TSH) 抑制治疗期间的分化型甲状腺癌(DTC)患者进行膳食调查,为对患者进行个性化膳食指导及营养干预研究提供参考依据。方法 从湖南省肿瘤医院甲状腺内科的门诊患者中收集行TSH抑制治疗的DTC患者,根据抑制治疗副作用危险分层标准,收集低、中、高危患者各200例,共600例患者作为研究对象。对所有入选病例进行膳食调查:一年食物摄入频率和3天24小时回顾法膳食调查。结果 TSH抑制治疗的DTC患者整体人群膳食摄入不足且膳食结构不合理;整体人群畜肉类摄入过多,鱼类及水产品、蛋、奶、豆、蔬菜、水果则摄入过少;整体人群脂类、碳水化合物、维生素E摄入量基本达到要求;蛋白质、膳食纤维、钙、铁、锌、硒、维生素A、维生素B1、维生素B2、维生素C、烟酸摄入明显不足;碘摄入基本符合要求;低、中、高危组膳食摄入不足率分别是21.0%、8.0%、11.5%;中危组畜肉类摄入最多,碘摄入有0.5%的患者超标;高危组牛奶摄入最少。结论 TSH抑制治疗的DTC患者膳食结构不合理及多种营养素摄入不足,在临床工作中应加强对整体人群的营养教育及针对性的干预,以降低TSH抑制治疗对心血管系统及影响骨代谢的风险。  相似文献   
110.
目的:研究全麻复合硬膜外在高龄患者腹腔镜直肠癌根治术中的应用效果。方法:选择60岁以上择期行腹腔镜直肠癌根治术患者60例,随机分为G组和GA组,每组各30例。G组患者为单纯全麻组,GA组患者为硬膜外复合全麻组。GA组患者在诱导前取L1~2硬膜外穿刺置管,予0.5%罗哌卡因5 ml,术中每小时追加5~7 ml。两组患者诱导方法相同:即,咪哒唑仑0.04 mg/kg、舒芬太尼0.3~0.4μg/kg、顺阿曲库铵0.15~0.20 mg/kg、依托咪酯0.2~0.3 mg/kg。监测并记录患者血压(BP),心率(HR),心电图(ECG),术中全麻药用量及术后患者苏醒情况。结果:GA组患者气腹后、拔管前BP、HR明显低于G组(P<0.05),且全麻药用量明显低于G组(P<0.05)。结论:全麻复合硬膜外应用于老年腹腔镜直肠癌手术较单纯全麻用药量减少,术中循环更加稳定,是腹腔镜直肠癌根治术比较安全可行的麻醉方法。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号