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31.
Recent event-related potential (ERP) studies revealed the selective processing of affective pictures. The present study explored whether the same phenomenon can be observed when pictures are presented only briefly. Toward this end, pleasant, neutral, and unpleasant pictures from the International Affective Pictures Series were presented for 120 ms while event related potentials were measured by dense sensor arrays. As observed for longer picture presentations, brief affective pictures were selectively processed. Specifically, pleasant and unpleasant pictures were associated with an early endogenous negative shift over temporo-occipital sensors compared to neutral images. In addition, affective pictures elicited enlarged late positive potentials over centro-parietal sensor sites relative to neutral images. These data suggest that a quick glimpse of emotionally relevant stimuli appears sufficient to tune the brain for selective perceptual processing.  相似文献   
32.
To evaluate the association of HLA types with Turkish patients with Graves' disease, HLA typing, clinical findings, and thyroid antibodies were correlated. The HLA types, clinical findings (ophthalmopathy and age at onset), and thyroid stimulating hormone (TSH) receptor (TRAb) and antithyroid microsomal antibodies (MAb) were analyzed. Seventy Turkish patients with Graves' disease and 306 control subjects were assessed. Serological HLA typing was performed in HLA A, B, C, DR, and DQ loci. There was a significantly increased prevalence of HLA B8, B49, DR3, DR4, and DR10 in Graves' disease. The association of Graves' disease with HLA DR3 was found to be less strong than previously described. The HLA DR4 antigen may contribute to the predisposition of Graves' disease in Turkey. The results suggest that HLA B7, B13, DR7, DQw2, and DQw3 may confer a protective effect for Graves' disease in Turkey. Patients carrying HLA B12, B18, and B44 haplotypes had a tendency to develop the disease at a later age. The difference from the other studies may be the result of the selection of the controls; in part, of the variability in serological typing reagents; and, also, of the rather weak HLA associations with the disease.This study was presented in part at the Annual Meeting of the National Endocrinology and Diabetes Association, Bursa, Turkey, May 25–28, 1992.  相似文献   
33.
Noradrenergic projections from the dorsomedial medulla reach the shell of the nucleus accumbens (NAcc), a structure implicated in both reward and feeding behavior. Despite this relationship, the effect of food reward on accumbens norepinephrine (NE) remains uninvestigated. In the course of assessing dopamine (DA) in the NAcc during sucrose ingestion [0.03, 0.1, and 0.3 M; Am. J. Physiol., Regul. Integr. Comp. Physiol., 286 (2004) R31], we also analyzed NE in the microdialysis samples from 14 ad-libitum-fed male rats. In contrast to DA, which increased with sucrose concentration (+20-47%) during sham feeding, in the same animals, NE levels were reduced (approximately -20%), regardless of sucrose concentration. These results demonstrate a novel relationship between accumbens DA and NE during orosensory stimulation with a preferred nutrient.  相似文献   
34.
Primary gall-bladder carcinoma producing granulocyte-colony stimulating factor (GCSF) is extremely rare. Only four cases, histologically investigated, have been reported to date in the English literature. We report a case of a 48-year-old female with primary gall-bladder carcinoma, associating with leukocytosis (15 700/mm3) and a high level of serum GCSF (54.0 pg/mL). The tumor was, histologically, a poorly differentiated adenocarcinoma with marked interspersed neutrophils invading into the primary tumor itself and the right lobe of the liver. Tumor cells distinctly showed positive immunoreaction in the cytoplasm with anti-GCSF antibody, and in the nucleus for anti-p53 antibody. After surgery, the leukocytosis and serum level of GCSF began to decrease. These findings confirmed the present case of GCSF-producing gall-bladder carcinoma, exhibiting leukocytosis. A total of five cases, including our case, reported as a GCSF-producing gall-bladder carcinoma were clinicopathologically reviewed.  相似文献   
35.
时间分辨荧光免疫分析方法学评价   总被引:19,自引:0,他引:19  
秦卫仕  田蓉 《免疫学杂志》2002,18(5):397-399,405
目的:通过内质控的定量分析,对时间分辨荧光分析的方法学进行客观评价。方法:以促甲状腺激素检测为例,对系统探测灵敏度 ,低、中、高持控血清的批内和批间精密度,批间稳定性参数Slope、ED20、ED50、ED80等4项指标,系统探测的准确度(回收试验),系统探测的有效性(平行试验),受试者工作特性曲线(receiver operator characteristic,ROC)等进行定量测定和描述。结果;TSH的最小测定值为0.002μU/mL.低、中、高3种质控样品批内和批间变异系数均小于5%,批间稳定性参数各变异系数均小于5%,与统计学要求相一致,且符合标准曲线质控参数的重现性。回收试验满足临床要求,符合检验统计结果。理论值与实测值间作回归分析,相关系数r=0.999。ROC显示,甲亢诊断的最佳阈值为0.3μU/mL,甲低诊断的最佳阈值为5.0μU/mL。甲亢敏感度为89.3%,特异度为93.3%,准确度为90.1%,阳性似然比为13.4,甲低敏感度为83.8%,特异率为90.9%,准确度为86.4%,阳性似然比为9.2。结论:时间分辨荧光免疫分析方法是一种效果好、准确度高、灵敏度高、特异性强、测试精度良好的自动化免疫分析方法。  相似文献   
36.
目的探讨大学生网络交往动机,为有效引导大学生认识和参与网络交往,同时为社会、学校、家长制定相应干预措施提供一定的心理依据。方法采用自编的大学生网络交往动机量表和Wrightsman编制的人性哲学量表—独立性分量表,对646名大学生的网络交往动机的差异进行研究。结果电大学生的网络交往动机更倾向于"交往/寻求帮助",而普通全日制高校学生更倾向于"消遣/娱乐";男生更倾向于"交往/寻求帮助"、"消遣/娱乐"、"好奇/追求时尚"、"网络优越感";理科学生更倾向于"交往/寻求帮助"、"网络优越感"、"消遣/娱乐"、"好奇/追求时尚";高年级大学生更倾向于"消遣/娱乐"、"好奇/追求时尚";独立性高的大学生网络交往的动机更倾向于"交往/寻求帮助"、"网络优越感"。结论大学生的网络交往动机因学校、专业、年级、性别、独立性人格特征不同而存在不同程度的差异。  相似文献   
37.
Lateralized rewarding brain stimulation affects forepaw preference in rats   总被引:1,自引:0,他引:1  
Rats trained to reach for food pellets into a narrow tubular feeder consistently prefer to perform this stereotype instrumental movement with either the left or right forepaw. In 16 rats with established handedness electrodes were implanted into both lateral hypothalami. The animals were rewarded by intracranial self stimulation (ICSS, 300 msec, 50 Hz, 20-60 microA) for reaching into a modified feeder for a plastic ball operandum, the movement of which between the bottom and entrance of the feeder was monitored by mechanical contacts. The rats readily continued to reach when ICSS was delivered immediately after the photoelectrically detected reach or after the displacement of the operandum. Most rats learned in a single session to modify the movement when ICSS delivery was made contingent upon holding the operandum between the bottom and entrance of the feeder for 256 or 512 msec. The efficiency of reaching (ratio of successful reaches to all reaches) decreased with increasing holding time; only a few animals were able to master a 1024 msec delay. Reaching was supported by ICSS of either lateral hypothalamus. Whereas in 8 rats the strongly expressed forepaw preference was not changed by lateralized ICSS, in 8 latently ambidextrous animals stimulation of the lateral hypothalamus ipsilateral to the preferred forepaw increased reaching with the normally non-preferred forepaw from 15% to 60%. Stimulation of the lateral hypothalamus contralateral to the preferred forepaw did not change the preference. The preference shift was equally well expressed in simple and difficult versions of the task. It is concluded that lateralization of motivational influences can be reflected in the asymmetry of the neural mechanisms processing the lateralized sensory signals and/or elaborating the lateralized motor output.  相似文献   
38.
The current study was designed to clarify the psychological functions most closely associated with frontal brain asymmetry. Electroencephalography (EEG) was recorded from 60 participants while they performed a delayed reaction time (RT) task that included manipulations of incentive, expectancy, and response. Significant alpha asymmetry effects were reflected in topographic differences across anterior EEG sites. Variations in monetary incentives resulted in parametric changes in anterior frontal alpha asymmetry. Manipulations of outcome expectancies were related to mid-frontal EEG changes that differed for men and women. Varied response requirements were related to central asymmetry patterns. Taken together, the findings suggest that regionally specific patterns of frontal asymmetry are functionally related to particular aspects of approach-withdrawal tendencies involved in the temporal guidance and regulation of goal-directed behavior.  相似文献   
39.
A number of anti-H-2 alloantisera containing antibody reactive with I region gene products (Ia) of the major histocompatibility complex cross-react with determinants expressed by human peripheral blood B lymphocytes. Such data have led to the conclusion that Ia and DR antigens share cross-reacting determinants. We have attempted to generate mouse primed T lymphocyte populations specific for defined I region gene product determinants which concomitantly recognize DR determinants on human peripheral blood leukocytes in primed lymphocyte typing (PLT) analysis. Mouse PLT cells were generated in primary MLC using strain combinations identical to those in which positive mouse/human cross-reacting antisera have been obtained. The resulting PLT cells exhibited strong, yet specific, secondary MLC responses against mouse cells expressing the Ia determinants used as the primary stimulus. In contrast, when examined on panels of human peripheral blood leukocytes, no reactivity was detected. This lack of cross-reactivity suggests that mouse T cells primed toward Ia determinants do not regularly recognize cross-reacting determinants of DR or D-associated antigens expressed on human PBLs. Consequently, mPLT cells are not a useful reagent in defining HLA-D region polymorphism.  相似文献   
40.
Normal men were infused for 4 hr with ACTH/MSH 4–10 or a control solution. Behavioral testing after the infusion indicated that subjects who received ACTH/MSH 4–10 were less anxious and had better visual memory than control subjects but the predominant effect of the heptapeptide was to increase visual attention. It was specualted that ACTH/MSH 4–10 may be uniquely coded for attentional functioning.  相似文献   
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