首页 | 本学科首页   官方微博 | 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   259747篇
  免费   24797篇
  国内免费   12408篇
耳鼻咽喉   3712篇
儿科学   4594篇
妇产科学   3465篇
基础医学   42581篇
口腔科学   6888篇
临床医学   21201篇
内科学   37293篇
皮肤病学   5227篇
神经病学   10933篇
特种医学   7604篇
外国民族医学   223篇
外科学   26264篇
综合类   42055篇
现状与发展   70篇
预防医学   8161篇
眼科学   4261篇
药学   18680篇
  44篇
中国医学   6508篇
肿瘤学   47188篇
  2024年   499篇
  2023年   3609篇
  2022年   6651篇
  2021年   9258篇
  2020年   8260篇
  2019年   7961篇
  2018年   8123篇
  2017年   8849篇
  2016年   9458篇
  2015年   10715篇
  2014年   15720篇
  2013年   16235篇
  2012年   14819篇
  2011年   16637篇
  2010年   13696篇
  2009年   13109篇
  2008年   13754篇
  2007年   14320篇
  2006年   13192篇
  2005年   11983篇
  2004年   10264篇
  2003年   8936篇
  2002年   7485篇
  2001年   6760篇
  2000年   5620篇
  1999年   4905篇
  1998年   4565篇
  1997年   4120篇
  1996年   3703篇
  1995年   3198篇
  1994年   2886篇
  1993年   2332篇
  1992年   1942篇
  1991年   1763篇
  1990年   1478篇
  1989年   1282篇
  1988年   1206篇
  1987年   963篇
  1986年   875篇
  1985年   1142篇
  1984年   963篇
  1983年   679篇
  1982年   715篇
  1981年   592篇
  1980年   501篇
  1979年   382篇
  1978年   269篇
  1977年   200篇
  1976年   161篇
  1975年   51篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Patients undergoing sentinel node biopsy (SLNB) for early oral squamous cell carcinoma (OSCC) who harbour occult metastases (pN+ve) may be at greater risk of mortality due to prolonged overall treatment times than those identified as pN+ve on elective neck dissection (ELND). A retrospective comparative survival analysis was therefore undertaken to test this hypothesis. Patients were identified from the South Glasgow multidisciplinary team (MDT) database. Group 1 comprised 38 patients identified as pN+ve, or who were false negative, on sentinel lymph node biopsy (SLNB). Group 2 comprised 146 patients staged pN+ve on ELND. The groups were compared with the Kaplan Meier method and Cox proportional hazards model. In addition, a matched-pair analysis was performed. A unique and specifically designed algorithm was deployed to optimise the pairings. No difference in disease-specific or overall survival was found between the groups. Patients undergoing SLNB as the initial neck staging modality in early OSCC and are identified as pN+ve do not appear to be at a survival disadvantage compared with those staged with ELND.  相似文献   
12.
13.
目的 运用CT区分脾脏血管性病变与淋巴瘤。方法 回顾性分析20例经手术、穿刺病理学检查证实的脾脏病变的发病年龄、性别、脾脏指数、病变大小、数目、有无液化、钙化、强化幅度、强化方式等特征,并进行统计学分析。结果 20例脾脏病变中,11例血管性病变(6例海绵状血管瘤,3例窦岸细胞血管瘤,2例硬化性血管瘤样结节性转化),9例淋巴瘤;两组间发病年龄、病变大小、数目、有无液化、钙化等差异无统计学意义;两组间脾脏指数、动脉期强化幅度差异具有统计学意义(P<0.05)。5例海绵状血管瘤呈不均匀性强化,1例呈渐进性填充式强化,2例窦岸细胞血管瘤呈“雀斑征”,1例硬化性血管瘤样结节性转化呈“辐轮征”;9例淋巴瘤实质部分均呈均匀、轻中度强化。结论 脾脏血管性病变与淋巴瘤CT表现不同,CT有助于明确诊断。  相似文献   
14.
Lessons Learned
  • The overall safety profiles of ipilimumab 3 mg/kg and 10 mg/kg administered every 3 weeks, were consistent between Chinese patients with solid tumors in the current study and patients from previous U.S. ipilimumab monotherapy studies. No new safety signals were identified.
  • The mean systemic exposures to ipilimumab (assessed by first dose area under the curve during the dosing interval and maximum serum concentration) were numerically lower in the Chinese patient population than in U.S. patients for both 3 mg/kg and 10 mg/kg doses; however, the range of serum concentrations in the Chinese and U.S. populations overlapped (3 mg/kg and 10 mg/kg), suggesting that ipilimumab pharmacokinetics was ethnically insensitive in this study.
BackgroundThis phase I, open‐label study assessed ipilimumab safety, tolerability, pharmacokinetics (PK), immunogenicity, and antitumor activity in Chinese patients with unresectable, metastatic, recurrent malignant melanoma (MM) or nasopharyngeal carcinoma (NPC).MethodsOf 39 patients enrolled, 25 received ipilimumab (11 patients received 3 mg/kg, and 14 patients received 10 mg/kg). Reasons for not receiving treatment were withdrawal of consent (3 patients), no longer meeting the criteria (10 patients), and one recorded as “other.” During the induction phase, patients received ipilimumab (3 mg/kg, i.v.), on day 1 of a 3‐week cycle, to a maximum of four doses or progressive disease (PD). During the maintenance phase at week 24, patients received ipilimumab (3 mg/kg, i.v.) on day 1 of a 12‐week cycle, to a maximum of 3 years or PD. Considering the co‐primary safety and PK endpoints, the successive dosing required nine patients with two or fewer dose‐limiting toxicities during the 42‐day observation period to proceed with a new cohort of nine patients at 10 mg/kg.ResultsIpilimumab safety and PK profiles were similar in Chinese and predominantly White populations. Ipilimumab was well tolerated. Most adverse events (AEs) were grades 1–2 and experienced by 11 patients treated with 3 mg/kg and 14 patients treated with 10 mg/kg. There were no new safety concerns. Incidence of anti‐ipilimumab antibodies was low (1 of 10 in the 3 mg/kg patients and 2 of 13 in the 10 mg/kg patients) and without safety implications. In the 3 mg/kg group, 8 of 11 patients had PD. In the 10 mg/kg group (all NPC, 0 MM patients), 11 of 14 patients had PD. Three patients had stable disease (one at 3 mg/kg and two at 10 mg/kg).ConclusionIpilimumab was well tolerated in Chinese patients, showing similar safety and PK to previous studies in predominantly White populations.  相似文献   
15.
ObjectivesMap regional lymph node metastases for lateralized oral cavity squamous cell carcinoma (OCSCC) and evaluate factors associated with regional metastases and recurrence.Materials and methodsRetrospective cohort study of 715 patients with lateralized OCSCC surgically treated in 1997–2011. Analysis was performed using log-rank, Kaplan-Meier, and multivariable logistic and Cox regression.ResultsRegional metastases were identified in ipsilateral levels IIA (24%), IB (18%), III (13%), V (9%), IV (7%), IA (2%) and IIB (1%) and the contralateral neck (3%). Lymphovascular invasion (LVI) (Hazard Ratio [HR] 2.2, 95% Confidence Interval [CI] 1.2–3.9) and T category (T3 vs. T1: HR 4.1, 95% CI 1.9–9.3; T4 vs. T1: HR 2.3, 95% CI 1.2–4.3) were associated with regional metastases. Most (71%) isolated regional metastatic recurrences were in undissected levels of the neck, including 58% in levels IV and V. Tumors of the hard palate (HR 4.3, 95% CI 1.2–16.1), upper alveolus (HR 3.2, 95% CI 1.0–4.7) or with LVI (HR 2.0, 95% CI 1.0–3.9) were associated with isolated regional recurrence. For upper alveolar/hard palate tumors, depth of invasion (DOI) ≥4 mm (P = .003) and LVI (P = .04) were associated with regional metastases.ConclusionsFor lateralized OCSCC, elective neck dissection of level IIB or the contralateral neck may rarely be needed, but additional surgical or radiation treatment of levels IV and V may be considered based on patient risk factors, including T category 3–4 or LVI. For upper alveolar/hard palate tumors, DOI ≥4 mm is an appropriate threshold for elective neck dissection.  相似文献   
16.
《Vaccine》2022,40(32):4296-4300
Advanced computational methodologies suggested SARS-CoV-2, nonstructural proteins ORF1AB, ORF3a, as the source of immunodominant peptides for T cell presentation. T cell immunity is long-lasting and compatible with COVID-19 pathology. Based on the supporting clinical data, nonstructural SARS-CoV-2 protein vaccines could provide global immunity against COVID-19.  相似文献   
17.
PurposeTo investigate the safety and efficacy of an aqueous polyethylene glycol-based liquid embolic agent, Embrace Hydrogel Embolic System (HES), in the treatment of benign and malignant hypervascular tumors.Materials and MethodsA prospective, single-arm, multicenter study included 8 patients, 5 males and 3 females, with a median age of 58.5 years (30–85 years), who underwent embolization in 8 tumors between October 2019 and May 2020. Technical success was defined as successful delivery of HES to the index vessel, with disappearance of >90% of the targeted vascular enhancement or, for portal vein embolization, occlusion of the portal branches to the liver segments for future resection. The volume of HES administered, ease of use (5 point Likert scale), administration time, and adverse events (AEs) were recorded. Evaluation was performed at 7, 30, and 90 days via clinical assessment and blood testing, and follow-up imaging was performed at 30 days.ResultsEight patients were enrolled, and 10 embolizations were performed in 8 lesions. Tumors included hepatocellular carcinoma (n = 4), renal angiomyolipoma (n = 3), and intrahepatic cholangiocarcinoma (n = 1). Technical success was 100%, and the average ease of use was 3.3 ± 1.0 SD. The HES delivery time was 1–28 minutes (median, 16.5 minutes), and the HES volume injected was 0.4–4.0 mL (median, 1.3 mL). All patients reached 30-day follow-up with imaging, and 6 patients reached 90-day follow-up. There were 3 serious AEs in 2 patients that were unrelated to the embolic agent.ConclusionHES resulted in a 100% embolization technical success rate. The product ease of use was acceptable, and no target vessel recanalization was noted on follow-up imaging at 30 days.  相似文献   
18.
19.
目的 探讨溶质载体蛋白(SLC)及其受体趋化因子受体7(CCR7)与I期非小细胞肺癌(NSCLC)淋巴结微转移的相关性。方法 选取2019年1月~2020年3月于我院就诊的I期NSCLC患者127例为研究对象,按照淋巴结微转移情况分为对照组92例和转移组35例,所有患者入院后均通过根治术切除病灶,通过免疫组化方式检测病灶中SLC7A11及CCR7含量,并收集患者临床资料、实验室检查资料及影像学检查资料。通过Logistic回归分析评价SLC7A11及CCR7与淋巴结微转移之间的关系。最后通过建立ROC曲线分析两者及其联合检测对NSCLC患者微淋巴结转移的预测价值。结果 两组患者SLC7A11及CCR7表达水平存在显著差异(P<0.05)。转移组患者病灶直径、支气管受累及TLG显著高于对照组(P<0.05)。病灶直径(OR=49.254,95%CI=11.062~507.604)是影响NSCLC淋巴结微转移的独立危险因素(P<0.05)。SLC7A11(OR=8.622)及CCR7(OR=8.709)表达水平是影响NSCLC淋巴结微转移的独立因素(P<0.05)。SLC7A11、CCR7及联合诊断对NSCLC淋巴结微转移具有较好的检测价值(均P<0.05)。联合检测特异度显著高于 SLC7A11及CCR7单独检测(2=7.292,15.125;均P<0.01)。结论 SLC家族的中SLC7A11及其受体CCR7与NSCLC患者微淋巴结转移显著相关。  相似文献   
20.
ObjectiveTo systematically evaluate the clinicopathological and prognostic value of extra-hepatic bile duct resection (EHBDR) in the surgical management of patients with gallbladder carcinoma (GBC), especially in non-jaundiced patients.MethodsPubMed, EMBASE and the Cochrane Library were searched up to March 1st 2021 for comparative studies between bile duct resected and non-resected groups. RevMan5.3 and Stata 13.0 software were used for the statistical analyses.ResultsEHBDR did not correlate with a better overall survival (OS) (P = 0.17) or disease-free survival (P = 0.27). No survival benefit was also observed in patients with T2N1 (P = 0.4), T3N0 (P = 0.14) disease and node-positive patients (P = 0.75), rather, EHBDR was even harmful for patients with T2N0 (P = 0.01) and node-negative disease (P = 0.02). Significantly higher incidences of recurrent disease (P = 0.0007), postoperative complications (P < 0.00001) and positive margins (P = 0.02) were detected in the bile duct-resected group. The duration of postoperative hospital stay between the two groups was comparable (P = 0.58). Selection bias was also detected in our analysis that a significantly higher proportion of advanced lesions with T3-4 or III-IV disease was observed in the bile duct-resected group (P < 0.00001). EHBDR only contributed to a greater lymph yield (P = 0.01).ConclusionEHBDR has no survival advantage for patients with GBC, especially for those with non-jaundiced disease. Considering the unfairness of comparing OS between jaundiced patients receiving EHBDR with non-jaundiced patients without EHBDR, we could only conclude that routine EHBDR in non-jaundiced patients is not recommended and future well-designed studies with more specific subgroup analyses are required for further validation.  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