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41.
Prevalence and mechanisms of development of asthma and airway hyperresponsiveness in athletes 总被引:4,自引:0,他引:4
A high prevalence of asthma and airway hyperresponsiveness (AHR) has been reported in the athlete population. Factors potentially predisposing athletes to these conditions have not been clearly identified. Although moderate exercise has been shown to be beneficial in patients with asthma, repeated high-intensity exercise could possibly contribute to the development of asthma and AHR. This report provides an overview of the prevalence and possible mechanisms of development of asthma and AHR in the athlete population. The prevalence of asthma and AHR are higher in athletes than in the general population, particularly in swimmers and athletes performing sports in cold air environments. Possible mechanisms involved in the development of asthma in athletes are still uncertain; however, the content and physical characteristics of the inhaled air seem to be important factors, while immune and neurohumoral influences could play a modulatory role. This report stresses the need for further studies to better define the aetiologic factors and mechanisms involved in the development of asthma and AHR in athletes, and proposes relevant preventive and therapeutic measures. 相似文献
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IS Park H Kiyomoto F Alvarez YC Xu HE Abboud SL Abboud 《American journal of kidney diseases》1998,32(6):1000-1010
The renal insulin-like growth factor-I (IGF-I) system has been implicated in the pathogenesis of renal hypertrophy, altered hemodynamics, and extracellular matrix expansion associated with early diabetes. The relative abundance of IGF binding proteins (IGFBPs) in the renal microenvironment may modulate IGF-I actions. However, the precise IGFBPs expressed in the glomerular and tubulointerstitial compartments during diabetic renal growth have not been characterized. In the present study, in situ hybridization studies were performed to examine the expression of IGFBP-1 to -6 messenger RNAs (mRNAs) 3, 7, and 14 days after streptozotocin (STZ) injection in rats. In control, nondiabetic kidneys, all six IGFBP mRNAs were differentially expressed with a predominance of IGFBP-5. The onset of renal hypertrophy in STZ-induced diabetes was associated with a rapid and site-specific induction of IGFBP-1, -3, and -5 mRNAs. In contrast, basal expression of IGFBP-2, -4, and -6 mRNAs was not altered in diabetic rats. IGFBP-5 mRNA expression increased in diabetic glomeruli, cortical, and inner medullary peritubular interstitial cells at days 3, 7, and 14. Although normal glomeruli failed to express IGFBP-3, it was induced concomitantly with IGFBP-5 in diabetic glomeruli and cortical peritubular interstitial cells. IGFBP-1 mRNA levels also increased in cortical tubular cells at each time point tested. Peak induction of IGFBP-3 and -5 was observed at day 3, whereas IGFBP-1 was delayed until day 7. IGFBP-1, -3, and -5 mRNA levels declined by day 14, but remained persistently elevated above control. By immunoperoxidase staining, similar alterations in the pattern of IGFBP-3 and -5 protein expression were observed at each time point. The preferential and site-specific increase in IGFBP-1, -3, and -5 suggest that these IGFBPs may regulate the local autocrine and/or paracrine actions of IGF-I and contribute to the pathogenesis of the early manifestations of diabetic nephropathy. 相似文献
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目的测定甘肃产五加中剌五加苷B、苷E的含量。方法高效液相色谱法,ODSKromasal柱。水乙晴(955)为流动相,检测波长222nm,柱温度25℃。结果本文可同时测定剌五加苷B、苷E的含量。剌五加苷B、苷E分别在0.064~0.320μg/ml;0.074~0.370μg/ml范围内峰面积与浓度呈线性关系,平均回收率分别为102.5%,RSD=4.2%,95.5%,RSD=4.6%。结论剌五加苷B、苷E在红毛五加中含量最高;茎皮中含量最高;剌五加苷E的含量高于苷B。 相似文献
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Subthalamic deep brain stimulation differently alters striatal dopaminergic receptor levels in rats 下载免费PDF全文
Carole Carcenac PhD Mathieu Favier PhD Yvan Vachez MSc Emilie Lacombe PhD Sébastien Carnicella PhD Sabrina Boulet PhD 《Movement disorders》2015,30(13):1739-1749
High‐frequency stimulation (HFS) of the subthalamic nucleus (STN) is recognized as an effective treatment for the motor symptoms of Parkinson's disease (PD), but its mechanisms, particularly as concern dopaminergic transmission, remain unclear. The aim of this study was to evaluate changes in the expression of dopaminergic receptors (D1, D2, and D3 receptors) after prolonged (4 h) unilateral STN‐HFS in anesthetized intact rats and rats with total dopaminergic denervation. We used [3H]SCH 23390, [125I]iodosulpride, and [125I]OH‐PIPAT to assess the densities of D1R, D2R, and D3R, respectively, within different areas of the striatum—a major input structure of the basal ganglia—including the nucleus accumbens. We found that STN‐HFS increased D1R levels in almost all of the striatal areas examined, in both intact and denervated rats. By contrast, STN‐HFS led to a large decrease in D2R and D3R levels, limited to the nucleus accumbens and independent of the dopaminergic state of the animals. These data suggest that the influence of STN‐HFS on striatal D1R expression may contribute to its therapeutic effects on motor symptoms, whereas its impact on D2R/D3R levels in the nucleus accumbens may account for the neuropsychiatric side effects often observed in stimulated PD patients, such as postoperative apathy. © 2015 International Parkinson and Movement Disorder Society 相似文献
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Joseph F Goldberg Lori D McLeod Sheri E Fehnel Valerie SL Williams Lynne R Hamm Kim Gilchrist 《Bipolar disorders》2010,12(1):32-44
Goldberg JF, McLeod LD, Fehnel SE, Williams VSL, Hamm LR, Gilchrist K. Development and psychometric evaluation of the Bipolar Functional Status Questionnaire (BFSQ). Bipolar Disord 2010: 12: 32–44. © 2010 The Authors.Journal compilation © 2010 John Wiley & Sons A/S. Objectives: Persistently impaired psychosocial functioning has been recognized in many individuals with bipolar disorder. However, existing measures of functional disability have been adapted for use in bipolar disorder based mainly on those developed for use in other conditions. The present study involved the development and validation of a new patient self‐report measure specific to bipolar disorder, the Bipolar Functional Status Questionnaire (BFSQ). Methods: Relevant constructs were identified, evaluated, and refined through an expert advisory panel in conjunction with patient interviews. Questionnaire items were vetted through iterative patient interviews. Psychometric properties were determined based on patient responses from implementation of the proposed 33‐item questionnaire in an 11‐site study of 596 patients with bipolar disorder across varied phases of illness. Results: Eight constructs were identified as fundamental to functional status in bipolar disorder: cognitive function, sleep, role functioning, emotional functioning, energy/vitality, social functioning, personal management, and sexual functioning. Psychometric validation supported item reduction to a 24‐item unidimensional scale, with high internal consistency (coefficient α’s = 0.93–0.95), high test‐retest reliability (intraclass correlation coefficient = 0.86, 95% confidence interval = 0.82–0.89), strong convergent validity with other functional disability measures (r’s > 0.70), and highly significant discriminant validity across illness phases, with large effect sizes (Cohen’s d > 0.70). Conclusions: The BFSQ is a psychometrically sound self‐report measure that can be used to effectively quantify functional status across different clinical states in patients with bipolar disorder. 相似文献
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