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Natural killer (NK)-like T cells are major histocompatibility complex- unrestricted cytotoxic T cells that are surface CD3-positive, express NK-cell antigens, and rearrange their T-cell receptor. Most neoplasms arising from this T-cell subpopulation have been a chronic lymphoproliferative disease referred to as T-large granular lymphocyte (LGL) leukemia. Only 10 NK-like T-cell lymphomas have been described in detail previously; this study presents the clinicopathologic features of six others and distinguishes these lymphomas from T-LGL leukemia. All patients presented with B-symptoms and often had marked hepatosplenomegaly without significant peripheral lymphadenopathy. Four of the six patients were immunosuppressed. All had CD3, CD8, CD56- positive tumors, presumably of hepatosplenic (n = 3), intestinal (n = 1), pulmonary (n = 1), or nodal (n = 1) origin. Three patients had lymphomatous bone marrow infiltrates, and four had peripheral blood involvement by neoplastic large lymphocytes, some of which had a blastic appearance or resembled virocytes. Azurophilic granules, ultrastructurally corresponding to cytoplasmic dense core and/or double density granules, were seen in all cases. T-cell clonality was shown in five tumors by Southern blot analysis, and three had abnormal karyotypes. Two untreated patients died 20 days after presentation, and three patients who received combination chemotherapy died within 5 months of presentation. One patient remains in complete remission 22 months after treatment. These findings suggest NK-like T-cell lymphomas are aggressive, are clinicopathologically distinct from T-LGL leukemia, and should be in the differential diagnosis of extranodal T-cell lymphoproliferations, including those in immunosuppressed patients. Furthermore, the LGL morphology, phenotype, and tissue distribution of some NK-like T-cell lymphomas suggest they arise from thymic- independent T cells of the hepatic sinusoids and intestinal mucosa.  相似文献   
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Objective: To study the relation between CD226 rs763361 gene polymorphism and CD226 serum level and to evaluate their role in susceptibility and disease activity of RA in a cohort of Egyptian individuals.

Methods: The serum level of CD226 was measured using a suitable ELISA kit and the CD226 rs763361 gene polymorphism was typed by PCR-RFLP for 112 RA patients and 100 healthy controls.

Results: Significant association with RA was found with CD226 T allele (OR (95%CI) = 1.6 (1.04–2.4), P = 0.032), and higher CD226 serum level (P = 0.001). Higher CD226 levels were associated with higher ESR values (P = 0.035), positive CRP (0.048), increased number of tender joints (P = 0.045), and higher DAS score (P = 0.035). Serum CD226 is an independent risk factor for the prediction of RA (P = 0.001). No correlations were found between the serum level of CD226 and different CD226 genotypes and also between them and RA activity grades.

Conclusion: The CD226 T allele may be susceptibility risk factors for the development of RA and the higher serum level of CD226 may be involved in the pathogenesis of RA in Egyptian patients. The serum level of CD226 and not CD226 genotypes could be considered as an independent risk factor for the prediction of RA within healthy individuals and also for RA disease activity.  相似文献   

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Objectives

To understand the vaginal bleeding/spotting experiences of postmenopausal (PM) women taking estrogen plus progestin therapies (EPT) and develop measures to assess these symptoms and their impact on women's daily lives in four countries.

Design

(1) Concept elicitation interviews were conducted with PM women in the US (n = 14), Italy (n = 15), Mexico (n = 15) and China (n = 15) to explore vaginal bleeding/spotting symptoms associated with EPT. The Post-Menopausal Bleeding Questionnaire (PMBQ) was also debriefed to evaluate understanding and comprehensiveness. (2) Based on concept elicitation, a single item electronic daily diary was developed and the PMBQ modified to form a 12-item impact measure. (3) The measures were pilot-tested and then cognitively debriefed with US women receiving EPT. All qualitative data was subject to thematic analysis.

Main outcome measures

The Vaginal Bleeding/Spotting Daily Diary, (VBS-DD) and Post-Menopausal Bleeding Impact Questionnaire (PMBIQ) were developed in this study.

Results

Concept elicitation identified vaginal bleeding and spotting as important symptoms for women taking EPT, impacting their emotional wellbeing, social life, ability to move freely, clothing and sexual activity. Based on pilot testing and cognitive debriefing, women demonstrated good understanding of the VBS-DD and the PMBQ was reduced to 10 items due to conceptual redundancy.

Conclusions

Women taking EPT in the US, China, Mexico and Italy reported vaginal bleeding/spotting symptoms that have a detrimental impact on their quality of life. Two new measures were developed to assess the severity and impact of vaginal bleeding/spotting specific to EPT. This work highlights the need for EPT-related symptoms to be a part of treatment decision-making.  相似文献   
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目的 研究HIV-1膜蛋白(Env)特定中和表位的改造对功能性假病毒形成及中和活性的影响.方法 采用环形诱变及Dpn I筛选的方法对Env进行定点突变,将2G12和2F5两个中和表位整合入不含该表位的BC亚型的Env上,比较改造对假病毒的形成情况及对2G12和2F5单抗的中和活性的影响.结果 对5株假病毒(BC02、BE03、BC04、BC05和BC12)的Env特定中和表位进行改造,其中BC04和BCl2的2G12表位改造后,不能形成假病毒,BC02、BC03和BC05增加2G12和2F5两个表位后,仍能够形成假病毒,且假病毒滴度较改造前无明显变化,改造后的BC03假病毒较改造前对单抗2G12和2175的中和活性均有所提高,而改造后的BE02和BC05假病毒较改造前对单抗2F5的中和活性增强,而对单抗2G12的中和活性无变化.结论 2G12中和表位部分位点的改造影响假病毒的形成,中和表位的增加能够提高单抗2G12的中和活性,为免疫原的优化提供了新思路.  相似文献   
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IntroductionErectile dysfunction (ED) is defined as the inability to attain and/or maintain penile erection sufficient for satisfactory sexual performance. Although intuitively related, the link between erection hardness and erection maintenance has not been formally established and quantified.AimTo understand the components of erection maintenance through statistical modeling.MethodsData from a double-blind placebo-controlled trial of fixed-dose sildenafil (100 or 50 mg, 8 weeks) with open-label extension of flexible-dose sildenafil (100 and 50 mg, 4 weeks) were analyzed. Erection maintenance was assessed with item 4 (how often erection was maintained) or item 5 (difficulty in maintaining erection) of the International Index of Erectile Function (IIEF). Erection hardness was assessed with the Erection Hardness Score.Main Outcome MeasuresLongitudinal modeling estimated mean treatment differences averaged over the double-blind phase for sildenafil 100 mg vs. placebo and 50 mg vs. placebo. Statistical mediation analysis was applied to partition the effect of sildenafil (pooled into one treatment group) on erection maintenance directly and indirectly through erection hardness.ResultsLongitudinal mean differences for sildenafil 100 and 50 mg vs. placebo were high (P < 0.0001 for each), with large standardized effect sizes (>0.8). Mediation modeling showed that sildenafil treatment affected maintenance directly as well as indirectly via erection hardness, when measured by IIEF item 4 (direct effect, 44.6%; indirect effect, 55.4%) or IIEF item 5 (direct effect, 56.9%; indirect effect, 43.1%).ConclusionsSildenafil treatment significantly improved erection maintenance, a physiologic requirement for satisfactory sexual performance. According to our model, only approximately half of the effect of sildenafil on erection maintenance was estimated to be driven through direct effects. Rather, the effect of sildenafil on erection maintenance seems to be substantially driven by erection hardness. Therefore, achievement of optimal initial erection hardness appears to be an important treatment goal for enhancing erection maintenance and achieving successful ED treatment. Claes HIM, Goldstein I, Althof SE, Berner MM, Cappelleri JC, Bushmakin AG, Symonds T, and Schnetzler G. Understanding the effects of sildenafil treatment on erection maintenance and erection hardness.  相似文献   
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Neuroimaging studies of human pain have revealed a widespread "pain matrix" distributed across both hemispheres of the brain. It is not resolved whether the pain matrix is biased toward one hemisphere, although behavioral and clinical data suggest that pain is perceived differently on the two sides of the body, and several neuroimaging studies suggest that pain processing in some regions of cortex may be lateralized toward the right hemisphere. The current study used fMRI in nine subjects to determine whether acute pain is preferentially processed in one cortical hemisphere. All cortical areas that were activated during the painful simulation were investigated, and several analytic approaches were used to directly compare activated regions to similar regions in the opposite hemisphere. Results indicated that four regions of the cortical pain matrix were activated either contralaterally (somatosensory cortex) or bilaterally (mid/posterior insula, anterior insula, and posterior cingulate). In addition, activation in five cortical regions during acute pain stimulation was localized either exclusively in the right hemisphere or was strongly lateralized to the right. These five areas were in the middle frontal gyrus, anterior cingulate, inferior frontal gyrus, medial/superior frontal gyri, and inferior parietal lobule. The location of some of these regions is consistent with the idea that there may be a right-lateralized attentional system to alert an organism to an infrequent, but behaviorally relevant, stimulus such as pain.  相似文献   
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