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1.
Neoadjuvant programmed cell death protein 1 (PD-1) blockade exhibits promising efficacy in patients with mismatch repair deficient (dMMR) colorectal cancer (CRC). However, discrepancies between radiological and histological findings have been reported in the PICC phase II trial (NCT 03926338). Therefore, we strived to discern radiological features associated with pathological complete response (pCR) based on computed tomography (CT) images. Data were obtained from the PICC trial that included 36 tumors from 34 locally advanced dMMR CRC patients, who received neoadjuvant PD-1 blockade for 3 months. Among the 36 tumors, 28 (77.8%) tumors achieved pCR. There were no statistically significant differences in tumor longitudinal diameter, the percentage change in tumor longitudinal diameter from baseline, primary tumor sidedness, clinical stage, extramural venous invasion status, intratumoral calcification, peritumoral fat infiltration, intestinal fistula and tumor necrosis between the pCR and non-pCR tumors. Otherwise, tumors with pCR had smaller posttreatment tumor maximum thickness (median: 10 mm vs 13 mm, P = .004) and higher percentage decrease in tumor maximum thickness from baseline (52.9% vs 21.6%, P = .005) compared to non-pCR tumors. Additionally, a higher proportion of the absence of vascular sign (P = .003, odds ratio [OR] = 25.870 [95% CI, 1.357-493.110]), nodular sign (P < .001, OR = 189.000 [95% CI, 10.464-3413.803]) and extramural enhancement sign (P = .003, OR = 21.667 [2.848-164.830]) was observed in tumors with pCR. In conclusion, these CT-defined radiological features may have the potential to serve as valuable tools for clinicians in identifying patients who have achieved pCR after neoadjuvant PD-1 blockade, particularly in individuals who are willing to adopt a watch-and-wait strategy.  相似文献   
2.
《Immunity》2022,55(9):1725-1731.e4
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4.
Geneticists have, for years, understood the nature of genome‐wide association studies using common genomic variants. Recently, however, focus has shifted to the analysis of rare variants. This presents potential problems for researchers, as rare variants do not always behave in the same way common variants do, sometimes rendering decades of solid intuition moot. In this paper, we present examples of the differences between common and rare variants. We show why one must be significantly more careful about the origin of rare variants, and how failing to do so can lead to highly inflated type I error. We then explain how to best avoid such concerns with careful understanding and study design. Additionally, we demonstrate that a seemingly low error rate in next‐generation sequencing can dramatically impact the false‐positive rate for rare variants. This is due to the fact that rare variants are, by definition, seen infrequently, making it hard to distinguish between errors and real variants. Compounding this problem is the fact that the proportion of errors is likely to get worse, not better, with increasing sample size. One cannot simply scale their way up in order to solve this problem. Understanding these potential pitfalls is a key step in successfully identifying true associations between rare variants and diseases.  相似文献   
5.
目的探讨喉癌患者血小板表面血小板膜糖蛋白Ⅱb/Ⅲa纤维蛋白原受体(PAC-1)、血小板P-选择素(CD62P)阳性表达率以及与患者临床病理特征和复发的关系。方法选取2014年1月~2015年12月间在我院耳鼻喉科手术治疗的116例喉癌患者,随访≥2年,并选取同期在我院体检的健康人群60例为对照组,采用流式细胞仪检测法检测外周血PAC-1和CD62P阳性率,并分析与临床病理特征、复发的关系。结果喉癌患者PAC-1和CD62P阳性表达率分别为(17.82±1.76)%和(22.87±3.13)%,明显高于健康人群(P<0.05);而且在喉癌患者PAC-1表达和CD62P表达呈正相关性(r=0.238,P<0.05)。T3-T4分期或N2-N3分期患者PAC-1和CD62P阳性表达率高于T1-T2分期或N0-N1分期患者(P<0.05)。另外远处转移组PAC-1和CD62P阳性表达率高于未发生转移组(P<0.05);随访期间有24例患者复发,复发率为20.69%。复发喉癌患者PAC-1、CD62P阳性表达率分别为(17.02±0.85)%和(21.84±1.17)%,明显高于未复发的喉癌患者(P<0.05)。经Logistics回归分析,PAC-1和CD62P是喉癌患者复发的独立危险因素(P<0.05)。结论PAC-1和CD62P阳性表达率与喉癌患者T分期、淋巴结转移和远处转移密切相关,同时可作为喉癌局部复发、区域淋巴结转移、远处转移的预测指标。  相似文献   
6.
目的研究双重排粪造影方式应用在结肠功能性便秘诊断当中的效果。方法文章所选择的调查对象来自2017年10月-2018年12月,均为在此期间本院收治的60例经临床病理诊断确诊为结肠功能性便秘患者,分析双重排粪造影方式和排粪造影的符合性。结果采用双重排粪造影方式诊断结肠功能性便秘59例得到确诊,占98.33%,和排粪造影相比,差异有统计学意义(P<0.05)。结论通过双重排粪造影方式进行结肠功能性便秘诊断,可以有效的提升诊断的效率,对于具体症型的确认也具有重要意义。  相似文献   
7.
目的:探讨睾丸旁促结缔组织增生性小圆细胞肿瘤的临床、病理特征、诊断及治疗。方法:回顾分析1例睾丸旁促结缔组织增生性小圆细胞肿瘤的诊治及随访资料,并复习相关文献。患者,男,27岁,因阴囊内无痛性肿块4个月就诊。体检于左侧阴囊内可扪及囊性肿块,同侧睾丸不能扪及。行左侧睾丸根治性切除术,术后辅以化疗。结果:术中见左侧睾丸旁多发结节状隆起肿块,质偏硬;术后病理检查肿瘤细胞呈巢状或梁索状结构并埋没在增生的纤维结缔组织中;免疫组化显示瘤细胞具有上皮源性、间质性和神经源性等多向分化的特点。术后已随访3年无瘤生存,预后良好。结论:促结缔组织增生性小圆细胞肿瘤有特异的临床病理特征,好发于年轻男性,手术切除肿瘤联合化疗是治疗的主要方法,睾丸旁促结缔组织增生性小圆细胞肿瘤比腹腔型预后相对好。  相似文献   
8.
There is no report of patients in whom pathological laughter, a rare condition characterized by uncontrollable episodes of laughter usually triggered by unrelated stimuli, was ever closely associated with a loss of consciousness overtly linked with the onset of such uncontrollable laughter, also referred to as a gelastic syncope. A 53-year-old man presented with a 4-month history of syncope following intense and uncoordinated laughter. Physical and neurological examination was normal and the patient had no other typical cerebellar signs. We found a mass in the cerebellar vermis abutting the floor of the fourth ventricle, which upon histological examination after surgery proved to be an ependymoma. We emphasize that pathological laughter and gelastic syncope could represent unique and sole features of a cerebellar disorder.  相似文献   
9.
Pathologic laughter and crying in ALS: a search for their origin   总被引:3,自引:0,他引:3  
Spells of laughter and crying are well known in patients with amyotrophic lateral sclerosis (ALS). Since ALS occurs mostly in older age groups, this brings up the possibility that aging changes in the brain could play a causative role in the origin of such spells. To rule out or at least reduce the complicating factor of aging, a study was made of the incidence of pathologic laughter and crying in patients whose motor neuron disease had started before the age of 45 years. The data were collected from 73 such individuals, all with confirmed ALS. All told, 36 had experienced episodes of pathologic laughter and/or crying. Of these, 20 had bouts of both laughter and crying. 9 bouts of crying alone and 7 spells of laughter alone. Nearly all with such emotional spells had developed bulbar involvement with the illness. The youngest patient with spells was 31 when his illness began and 35 when he started to have bouts of crying.  相似文献   
10.
对60例病毒性肝炎患者进行肝穿刺活检,结果发现,临床与病理诊断的符合率为46.6%,其中,急性肝炎的诊断符合率最低(23.8%),慢性迁延型肝炎(慢迁肝)为44.8%;HBsAg阳性首次发病的患者中,急性乙型肝炎仅为11.2%(2/18);临床诊断的慢性活动型肝炎(慢活肝)仅为病理检出的25.7%(9/35);肝炎患者中脾肿大,凝血酶元时间延长、A/G值<1.2、抗HBcIgM阳性可作为慢活肝与慢迁肝鉴别的重要指标。这些对提高病毒性肝炎临床分型诊断的准确率及指导临床治疗有意义。  相似文献   
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