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21.
The effects of complement activation on pulmonary vascular permeability are disputed. In rabbit lungs perfused with autologous blood, zymosan activated plasma (ZAP) induced a moderate increase in pulmonary vascular resistance (PVR), but did not detectably change the vascular permeability within 2 h. The stronger neutrophil granulocyte (PMN) activator, phorbol myristate acetate (PMA), usually gave larger PVR increases and also increased pulmonary vascular permeability. Lungs from neutropenic animals, similarly perfused and given PMA, showed unchanged PVR reactions but had no apparent increase in vascular permeability. Lungs perfused with cell-free medium and given PMA displayed modest PVR increases, and no measurable permeability change. The lung preparatory procedure itself markedly influenced leukocyte circulation. Exsanguination of lung donors decreased the concentration of circulating PMN significantly, and they virtually disappeared from the perfusate within minutes after start of lung perfusion. PMN-mediated effects must therefore have been caused by cells already sequestered in the lungs. We conclude that ZAP does not induce an increased pulmonary vascular permeability in isolated, perfused rabbit lungs, in contrast to PMA. The permeability effects of PMA appear to be PMN dependent.  相似文献   
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Summary In an open, randomized, comparative, between-patient trial, 45 postmenopausal women were treated for 4 months with cyclical transdermal oestradiol 0.05 mg per day or oral conjugated equine oestrogens 0.625 mg per day, in both cases, plus, medroxyprogesterone acetate 10 mg per day on the last 8 days of each cycle. Similar relief from postmenopausal symptoms was obtained with both treatments. Post-treatment histological evaluation of the endometrium did not reveal neoplastic or hyperplastic change in any patient.Early follicular-phase plasma oestradiol levels were observed only after transdermal oestradiol. There was a significant reduction in serum total cholesterol and LDL cholesterol in both treatment groups, with no difference between treatments, whereas serum triglyceride levels were decreased only by transdermal oestradiol. Plasma calcium and phosphorus fell significantly and serum intact parathyroid hormone rose significantly, with no difference between the therapies. No significant changes were observed in clotting factors.Transdermal oestradiol appears to be an effective and safe hormonal replacement therapy, and this route of administration may be responsible for the more useful action of the drug on serum lipids and plasma oestradiol levels.  相似文献   
23.
根据蓝四氮唑与泼尼松生成蓝色产物,并于525nm 波长处测定吸光度。测定条件为:反应管长度为3.8m(0.5mm id);流速为1.6ml/min;反应温度为55±0.5℃;注射样品溶液为100μl;本测定系统的测定速度可达100次/h;线性范围可达0.09mg/ml;检测限量为1.54μg/ml;测定结果的变异系数小于1%。  相似文献   
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采用一阶导数分光光度法测定醋酸曲安缩松注射液的含量,平均回收率为99.82%,RSD为0.39%。方法简便快速,结果满意。  相似文献   
27.
The study was designed to examine the effect of hormone replacement therapy (HRT) and low-dose vitamin D (Vit D) supplementation on the prevention of bone loss in non-osteoporotic early postmenopausal women and to determine whether Vit D supplementation can give additional benefit to an already optimized estrogen regimen. The effects of HRT and Vit D on bone mineral density (BMD) were studied in postmenopausal women in a 2.5-year randomized placebo-controlled study. The study population was a subgroup of the Kuopio Osteoporosis Risk Factor and Prevention Study (OSTPRE) (n=13100). A total of 464 early postmenopausal women were randomized to four groups: (1) HRT (a sequential combination of 2 mg estradiol valerate and 1 mg cyproterone acetate (E2Val/CPA); (2) vitamin D3 (cholecalciferol, 300 IU/day); (3) HRT+Vit D; and (4) placebo (calcium lactate; 93 mg Ca2+/day). Lumbar (L1–4) and femoral neck BMD were determined by dual-energy X-ray absorptiometry before and after 2.5 years of treatment. After 2.5 years, lumbar BMD had increased by 1.8% in the HRT group (p<0.001) and by 1.4% in the HRT+Vit D group (p=0.002), whereas lumbar BMD had decreased by 3.5% (p<0.001) in the Vit D group and by 3.7% (p<0.001) in the placebo group. The loss of femoral neck BMD was lower in the HRT (–0.3%) and the HRT+Vit D (–0.9%) groups compared with the Vit D (–2.4%) and the placebo groups (–3.7%). This study confirms the beneficial effect of HRT on BMD. It also shows that low-dose vitamin D supplementation has only a minor effect in the prevention of osteoporosis in non-osteoporotic early postmenopausal women and does not give any benefit additional to that of HRT alone.  相似文献   
28.
Noninvasive techniques for the assessment of cardiac metabolism are important for the detection of potentially salvageable tissue in jeopardized areas of the myocardium. The correct identification of hibernating and stunned myocardium in patients with severely depressed cardiac function can have vital therapeutic consequences for the patient. Changes in myocardial fatty acid and glucose metabolism during acute and prolonged ischemia can be traced by positron-emitting or gamma-emitting radiopharmaceuticals. Alternatively,31P-labeled magnetic resonance spectroscopy can be used for the assessment of high-energy phosphate metabolism. It is not yet clear which modality will emerge as the most useful in the clinical setting. Positron emission tomography (PET) that uses combinations of flow tracers and metabolic tracers offers unique opportunities for quantification and high-resolution static and rapid dynamic studies. Currently, assessment of glucose metabolism with18F-fluorodeoxyglucose is regarded as the gold standard for myocardial viability and prediction of improvement of impaired contractile function after revascularization. However, preserved oxidative metabolism may be required for potential functional improvement, and therefore assessment of residual oxidative metabolism by11C-labeled acetate PET may prove to be more accurate than18F-fluorodeoxyglucose PET, which reflects both anaerobic and oxidative metabolism. Moreover, because fatty acids are metabolized only aerobically, they are excellent candidates for the clinical assessment of myocardial viability and prediction of functional improvement after revascularization. Especially derivatives of fatty acids that are not metabolized but accumulate in the myocyte are attractive for myocardial imaging. Examples are123I-beta-methyl-p-iodophenyl pentadecanoic acid and 15-(o-123I-phenyl)-pentadecanoic acid. These tracers can be detected by planar scintigraphy and single-photon emission computed tomography, which are more economical and widely available than PET. In addition, 511 keV collimators have been developed recently, making the detection of positron emitters by planar scintigraphy and single-photon emission computed tomography feasible. The experience with31P-labeled magnetic resonance spectroscopy in humans is still limited. With current magnetic resonance spectroscopic techniques, insufficient spatial resolution is achieved for clinical purposes, but the possibility of serial measurements to monitor rapid changes of phosphate-containing molecules in time makes magnetic resonance spectroscopy very valuable for the research of myocardial metabolism.  相似文献   
29.
目的:探讨中国妇女哺乳期使用迪波盖司通后血清和乳液醋酸甲羟孕酮(MPA)浓度变化。方法:10名产后哺乳妇女单次注射迪波盖司通(含MPA150mg),在注射后的第1、2、4、6、8、10和12周采集血样和乳液样本,用放射免疫方法测定MPA。结果:血清MPA浓度于注射后第1周最高,到第2、4周时下降明显,第4周后浓度下降趋势逐渐缓慢。乳液MPA浓度在第1周为最高,第2周比第1周降低了约1/2,之后10周平均浓度变化波动在5.09-8.15ng/ml之间。观察期间乳液/血清MPA浓度比值和曲线下浓度面积比值均为0.55。对象之间和同一对象不同时间点乳液/血清MPA浓度存在明显个体差异。结论:哺乳期使用迪波盖司通,将导致血液和乳液中含有一定量的MPA。  相似文献   
30.
利用人T淋巴母细胞(Jurkat)细胞系作为研究对象。企图探探索细胞外基质成份及肌醇磷脂细胞信息传递系统与细胞移动的关系。研究结果表明:当细胞被伏波醇酯(PMA)处理过后,其粘连性与移动件对纤维连结蛋白(FN)底物的反应在已是高水平的基础上有更进一步提高的作用。与FN刊相反的是,未经PMA处理处的Jurkat细胞对层粘连蛋白(Lm)底物却无明显的粘连性及移动性增加的反应,尽管在PMA处理过4小时内亦无任何的增强。但是,当PMA作用于细胞24一48小时后则明显池增加其Lm底物的粘连性及移动性反应,表明了其明显的协同作用。分别用抗FN、抗Lm及蛋白激酶C抑制剂Staurosprine(SP)时均起到特异性的抑制作用。可见,协同作用的产生是通过蛋白激酶C激活后的-段时间内,使细胞表面Lm受体密度增加而对底物Lm反应增强所致。  相似文献   
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