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101.
Hartmann IJ Prins MH Büller HR Banga JD;ANTELOPE study group 《Thrombosis and haemostasis》2001,85(4):604-608
We evaluated selection bias in a prospective study of 1,162 consecutive patients with suspected pulmonary embolism. Of these, 983 were eligible, and 627 could actually be included. During two months extensive data were collected on all non-included patients. Finally, our patient characteristics were compared with those of the PIOPED study (1990) and the study of Hull et al. (1994). Compared with included patients, the non-included patients had more often non-diagnostic V/Q scans (50% vs. 36%, p <0.01) and were more often already hospitalized (31% vs. 22%, P = 0.04). The subgroup of patients not included due to refusal or inability to give informed consent (IC) was older (mean age 61 vs. 53 years, P <0.01), more often suffered from malignancies (26% vs. 11%, P <0.01) and frequently had non-diagnostic V/Q scans (57%) as compared to included patients. In our study, 54% of all patients screened was eventually included versus 27% in the PIOPED study. In the PIOPED study patients who had contra-indications for pulmonary angiography were excluded, while in the study of Hull et al. those with inadequate cardiorespiratory reserve were excluded. In studies on new diagnostic technologies, patient selection bias does occur. The potential for such a selection bias should be taken into account when diagnostic strategies are devised to improve their generalizability and acceptability. 相似文献
102.
高效液相色谱法测定寒痹停片中士的宁含量 总被引:6,自引:0,他引:6
目的:建立用HPLC测定寒痹停片中士的含量的方法。方法:氰基柱;流动相-甲醇-水-三乙胺-乙酸(9800:155:15:30);紫外检测波长254nm。结果:在4~20ug/ml范围内,标准曲线回归方程为:Y=-2803+8967x(r=0.9997),RSD=1.65%?加样回收率的平均值为99.82%。结论:实验表明,这是一个适用于生产控制和产品质量检验的简单、快速、准确的方法。 相似文献
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106.
ANA JP MORAES POLLYANA MF SOARES AURA L ZAPATA ANA PN LOTITO ADRIANA ME SALLUM CLOVIS AA SILVA 《Pediatrics international》2006,48(1):48-53
Background: The purpose of the present paper was to describe the clinical manifestations and treatment of patients with panniculitis. Methods: From January 1983 to December 2002, 4294 patients were treated for pediatric rheumatological diseases at Pediatric Rheumatology Unit, University of São Paulo, Brazil. Of these, 35 children and adolescents (0.8%) presented with panniculitis: erythema nodosum (EN) or Weber–Christian disease (WCD). Clinical characteristics, laboratory exams, biopsy of the lesion, treatment and clinical course were studied. Results: Of the 35 patients, 29 presented with EN and six with WCD, one of these with cytophagic histiocytic panniculitis. Mean age at symptom onset was 85 months (6–204 months) and the mean duration of follow up was 55 months (1–144 months). All the patients presented with inflammatory subcutaneous nodules. The patients with WCD presented with systemic manifestations and cutaneous atrophy. The principal etiologies of EN were streptococcal infection (42%), undetermined (13.5%), pulmonary tuberculosis (10%), and acute rheumatic fever (10%). Biopsy of the nodules indicated septal panniculitis in 14 patients with EN and lobular panniculitis without vasculitis in the patients with WCD, one of which had cytophagic histiocytic panniculitis. There was recurrence in 11 patients (38%) with EN and in all those with WCD. Non‐steroidal anti‐inflammatory drugs were used in 15 patients with EN and corticosteroids and/or immunosuppressive drugs in the six patients with WCD. Three patients died. Conclusions: EN is the most frequent panniculitis, with a benign course and is mainly associated with infections. WCD is a severe disease, with systemic involvement, that proceeds with cutaneous atrophy and requires the use of corticosteroids and or immunosuppressive drugs. 相似文献
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Purpose
This study investigated in vitro transdermal delivery of methotrexate through dermatomed porcine ear and cadaver human skin treated with poly (D,L-lactide-co-glycolide) acid microneedles or fractional ablative laser.Methods
PLGA microneedles were fabricated and characterized using scanning electron microscopy and mechanical assessment techniques. The integrity of treated skin was evaluated by rheometer, transepidermal water loss, and skin electrical resistance measurements. Successful skin microporation was demonstrated by dye binding, histology, pore uniformity, confocal laser microscopy, and DermaScan studies. In vitro permeation experiment was performed on Franz diffusion cells to determine drug delivery into and across the skin.Results
Both physical treatments resulted in a considerable decrease in skin resistance and an increase in transepidermal water loss value. The laser-created microchannels were significantly larger than those formed by microneedles (p?<?0.05). An effective force of 41.04?±?18.33 N was required to achieve 100% penetration efficiency of the microneedles. For both porcine ear and human skin, laser ablation provided a significantly higher methotrexate permeability into the receptor chamber and skin layers compared to microneedle poration and untreated skin (p?<?0.05).Conclusions
Both fractional ablative laser and polymeric microneedles markedly enhanced in vitro transdermal delivery of methotrexate into and across skin.109.
Purpose To characterize solid maltose microneedles and assess their ability to increase transdermal drug delivery.
Materials and Methods Microneedles and microchannels were characterized using methylene blue staining and scanning electron microscopy. Diffusion
pattern of calcein was observed using confocal scanning laser microscopy. Transepidermal water loss (TEWL) measurements were
made to study the skin barrier recovery after treatment. Uniformity in calcein uptake by the pores was characterized and percutaneous
penetration of nicardipine hydrochloride (NH) was studied in vitro and in vivo across hairless rat skin.
Results Microneedles were measured to be 508.46 ± 9.32 μm long with a radius of curvature of 3 μm at the tip. They penetrated the
skin while creating microchannels measuring about 55.42 ± 8.66 μm in diameter. Microchannels were visualized by methylene
blue staining. Pretreatment with microneedles resulted in the migration of calcein into the microchannels. TEWL increased
after pretreatment and uptake of calcein by the pores was uniform as measured by the pore permeability index values. NH in vitro transport across skin increased significantly after pretreatment (flux 7.05 μg/cm2/h) as compared to the untreated skin (flux 1.72 μg/cm2/h) and the enhanced delivery was also demonstrated in vivo in hairless rats.
Conclusion Maltose microneedles were characterized and shown to create microchannels in the skin, which were also characterized and shown
to improve the transdermal delivery of NH. 相似文献
110.
P Hernandez-Pe?a JP Poullier CJM Van Mosseveld N Van de Maele V Cherilova C Indikadahena G Lie T Tan-Torres David B Evans 《Bulletin of the World Health Organization》2013,91(11):808-815