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M Ardigo I Malizewsky ML Dell'Anna E Berardesca M Picardo 《Journal of the European Academy of Dermatology and Venereology》2007,21(10):1344-1350
BACKGROUND: Vitiligo is the most common pigmentary disorder with a global incidence from 0.1% to 2% in different geographical areas. Histopathology and histochemistry have shown the reduction of melanocytes in achromic patches, but microscopic changes of lesional and non-lesional skin are still not completely understood. Reflectance confocal microscopy (RCM), based on the different light reflectance index of cutaneous structures, allowed in vivo, en face microscopic evaluation of superficial skin layers with a resolution similar to skin histology. AIM: The purpose of this study was to evaluate RCM features of lesional and non-lesional skin of vitiligo patients. Moreover, re-pigmented areas were taken into consideration in order to evaluate melanocyte response to ultraviolet B (UVB) radiation. SUBJECTS AND METHODS: Sixteen patients of different phototypes affected by active non-segmental vitiligo and 10 controls were enrolled in the study. In vivo skin imaging was done using a commercially available RCM (Lucid, Vivascope 1500. Re-pigmented areas from 6 to 16 patients (after UVB narrow-band therapy) were also examined. RESULTS: Vitiligo lesions showed the disappearance of the bright rings normally seen at the dermo-epidermal junction. Moreover, non-lesional skin of vitiligo patients showed unexpected changes as the presence of half-rings or scalloped border-like features of the bright papillary rings. In re-pigmented areas after UVB narrow band therapy, the presence of activated, dendritic melanocytes was seen. CONCLUSIONS: Considering our results, and following further studies, RCM clinical applications could be used in the therapeutic monitoring and evaluation of the evolution of vitiligo. 相似文献
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G E Hogarty C M Anderson D J Reiss S J Kornblith D P Greenwald C D Javna M J Madonia 《Archives of general psychiatry》1986,43(7):633-642
Relapse rates averaging 41% in the first year after discharge among schizophrenic patients receiving maintenance neuroleptic treatment led to the development of two disorder-relevant treatments: a patient-centered behavioral treatment and a psychoeducational family treatment. Following hospital admission, 103 patients residing in high expressed emotion (EE) households who met Research Diagnostic Criteria for schizophrenia or schizoaffective disorder were randomly assigned to a two-year aftercare study of family treatment and medication, social skills training and medication, their combination, or a drug-treated condition. First-year relapse rates among those exposed to treatment demonstrate a main effect for family treatment (19%), a main effect for social skills training (20%), and an additive effect for the combined conditions (0%) relative to controls (41%). Effects are explained, in part, by the absence of relapse in any household that changed from high to low EE. Only the combination of treatment sustains a remission in households that remain high in EE. Continuing study, however, suggests a delay of relapse rather than prevention. 相似文献
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Venous duplex imaging: should it replace hemodynamic tests for deep venous thrombosis? 总被引:2,自引:0,他引:2
A J Comerota M L Katz L L Greenwald E Leefmans M Czeredarczuk J V White 《Journal of vascular surgery》1990,11(1):53-9; discussion 59-61
Noninvasive diagnosis of deep venous thrombosis has traditionally relied on detection of alterations in venous hemodynamics. Although phleborheography is among the most sensitive tests, it is inadequate for diagnosing infrapopliteal and nonocclusive proximal thrombi and for surveillance of patients at high risk for deep venous thrombosis. Venous duplex imaging is a new technique being rapidly accepted, however, without the same critical analysis given to previous diagnostic modalities. The purpose of this study is to evaluate the diagnostic acumen of venous duplex imaging compared to phleborheography and ascending phlebography in two distinct patient groups, and to determine whether patient selection, and thus the location or magnitude of thrombi have significant influence on these diagnostic tests. One hundred ten extremities in 103 patients were prospectively evaluated with venous duplex imaging, phleborheography, and ascending phlebography within the same 24-hour period. Patients were categorized into one of two groups: Diagnostic--patients evaluated because of clinical suspicion of acute deep venous thrombosis; and Surveillance--patients at high risk of postoperative deep venous thrombosis after total joint replacement, but not symptomatic. Patients in the diagnostic group had a greater frequency of deep venous thrombosis (p less than 0.001) and significantly more occluding above-knee thrombi (p = 0.054) compared to those in the surveillance group. Phleborheography detected 73% (27/37) of above-knee thrombi in the diagnostic group compared to 29% (2/7) in the surveillance group (p = 0.036). This difference was not noted with venous duplex imaging, which detected 100% of above-knee thrombi in both diagnostic and surveillance groups and 78% (7/9) of all below-knee thrombi.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study. 相似文献
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高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献