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61.
Tsakiris S Schulpis KH Tjamouranis J Michelakakis H Karikas GA 《Clinical biochemistry》2002,35(8):568-619
OBJECTIVE: a) To evaluate acetylcholinesterase (AChE) activities in erythrocyte membranes from phenylketonuric (PKU) patients and controls and to correlate with their plasma phenylalanine (Phe), tyrosine (Tyr), alanine (Ala) and dopamine (DA) levels. b) To determine the in vitro effects of Phe, Ala and Phe plus Ala on their AChE activities. DESIGN AND METHODS: AChE activities were determined spectrophotometrically in erythrocyte membranes from PKU children (n = 12) adhering to their diet (group A), from 11 "off diet" (group B) and from 23 controls. Their plasma amino acids were evaluated with an amino acid analyser and DA with an HPLC method. Ala (1.8 mM) and/or Phe (1.8 mM) were added in the enzyme incubation medium from controls, whereas only Ala was added in that from group B. RESULTS: AChE activity (1.19 +/- 0.05 deltaOD/min x mg protein), Tyr (46 +/- 17 micromol/L) and DA (56 +/- 18 micromol/L) were remarkably decreased by about 60% in group B as compared to those of group A (3.01 +/- 0.18 deltaOD/min x mg protein, 115 +/- 39 micromol/L, 137 +/- 29 micromol/L, respectively, p < 0.001) and controls (3.13 +/- 0.16 deltaOD/min x mg protein, 117 +/- 44 micromol/L, 142 +/- 22 micromol/L, respectively, p < 0.001). Phe negatively correlated with AChE activity and positively with plasma Tyr and DA. Ala reversed the inhibited AChE by Phe in erythrocyte membranes from healthy children to control values, whereas no reverse effect was observed on the enzyme activity from PKU patients. CONCLUSIONS: a) The low levels of DA and its precursor Tyr are due to the high Phe blood levels, as a consequence of the decreased activity of Phe-hydroxylase in the liver of our patients. So, high Phe blood levels inhibit AChE in PKU patients, probably resulting in higher acetylcholine concentrations. b) Determination of AChE in erythrocyte membranes from PKU could be a useful marker for the neurotoxic effects of Phe. 相似文献
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刑事警察心理健康调查分析 总被引:2,自引:0,他引:2
①目的了解刑事警察的心理健康状况,为心理干预提供依据。②方法对济宁市刑警队员进行症状自评量表(Symptom Checklist 90.SCL-90)、焦虑自评量表(Self—rating Anxiety state,SAS)、抑郁自评量表(Self—rating Depression scale,SDS)评定。③结果济宁市刑警队员的SCL-90、SAS、SDS量表评分与全国常模相比存在显著性差异。④结论。刑事警察职业是一种特殊职业,该职业对队员的心理健康有显著的影响,这种影响随着从事刑警工作时间的不同而改变。 相似文献
64.
目的探讨黄芪注射液抗肝纤维化及对TGF-β1、Col-Ⅰ表达的影响。方法将35只SD大鼠随机分为正常对照组、CCl4诱导肝纤维化模型组和黄芪干预组。至造模第10周,处死所有大鼠,采用PV免疫组化方法检测Col-Ⅰ在各组肝组织中的表达,ELISA法检测TGF-β1在各组血清中的表达。结果经CCl4诱导成功建立大鼠肝纤维化模型,随着肝纤维化程度的进展,肝组织中Col-Ⅰ和血清中TGF-β1表达明显增强。在正常对照组、黄芪干预组和肝纤维化模型组肝组织中Col-Ⅰ表达的平均光密度值分别为0.298、0.315、0.503,模型组与前两组比较差异均有显著性(P〈0.01),而黄芪干预组与正常组肝组织比较差异无统计学意义(P〉0.05)。在正常对照组、黄芪干预组和肝纤维化模型组大鼠血清中TGF-β1表达含量分别为491.29pg/L、629.91pg/L、959.09pg/L,呈递增趋势。模型组与前两组比较差异均有显著性(P〈0.01),黄芪干预组与正常组比较其表达含量无显著差异(P〉0.05)。结论黄芪注射液可以显著抑制实验性肝纤维化大鼠模型的肝纤维化,这种抑制作用可能与抑制I型胶原蛋白及TGF-β1的表达有关。 相似文献
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66.
Intracranial abnormalities in infants treated with extracorporeal membrane oxygenation: imaging with US and CT 总被引:1,自引:0,他引:1
Findings at neuroimaging in 100 consecutive infants treated with extracorporeal membrane oxygenation (ECMO) are presented. Imaging in these infants consisted of pretreatment cranial ultrasonography (US), daily US studies while on ECMO, and follow-up cranial computed tomography (CT) after treatment. There were findings of abnormalities in 43 patients. Thirty had intracranial bleeding, often of unusual extent and distribution. Thirteen additional infants had nonhemorrhagic abnormalities alone. Bleeding considered to be major was seen in 12% of infants. Large parenchymal hemorrhages and infarcts, cerebellar hemorrhages, and diffuse edema were the most significant abnormalities, with a 50% mortality (eight of 16 patients). No lateralization was noted with respect to distribution of bleeding sites or areas of nonhemorrhagic abnormalities. US was a sensitive but imperfect screening tool for intracranial abnormalities. Abnormalities missed with US included peripheral and small parenchymal lesions, subarachnoid hemorrhage, cerebral atrophy, and sagittal sinus thrombosis. 相似文献
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69.
Peptic ulcer and gastric carcinoma: diagnosis with biphasic radiography compared with fiberoptic endoscopy 总被引:1,自引:0,他引:1
Shaw PC; van Romunde LK; Griffioen G; Janssens AR; Kreuning J; Eilers GA 《Radiology》1987,163(1):39-42
The diagnostic value of biphasic radiographic examination of the stomach and duodenum was compared with that of fiberoptic endoscopy in a prospective, blinded study of 385 patients with dyspepsia. This investigation was directed at gastric malignancies and peptic ulcers. Methodologically there is no absolute standard for a study of this kind because histologic examination is useful for detection of cancer but inadequate for ulcers. As an alternative, kappa indexes and the sensitivity and specificity, as derived by Hui and Walter, were calculated and compared. For the detection of gastric carcinoma, radiographic and endoscopic findings had almost perfect agreement beyond chance. For gastric ulcers, radiography and endoscopy had substantial agreement, which became perfect if small ulcers (less than 5 mm) were excluded. For duodenal ulcers, radiography had a lower sensitivity than endoscopy; this disagreement disappeared if small ulcers were excluded. Both methods have equal merit; choice of the initial diagnostic procedure will therefore depend on cost, discomfort to the patient, and risk of complications. 相似文献
70.
Parathyroid scintigraphy using a double-tracer (T1-201, Tc-99m) subtraction technique depicted 17 of 23 (74%) parathyroid adenomas in patients with and without previous neck operations. High-resolution (10-MHz) ultrasound (US) depicted 18 (78%) of these adenomas. Average tumor size depicted by US was 17 X 10 X 8 mm (excluding a giant adenoma) and 19 X 10 X 9 mm by scintigraphy. Alone, neither modality was particularly sensitive in the depiction of primary hyperplasia of the parathyroid glands, but combined techniques were more effective than the use of a single modality. With both US and T1-201 scintigraphy, only two of 23 cases of parathyroid adenoma in the neck were missed, and none of the eight cases of secondary hyperplasia were missed. In 11 patients who had previously undergone neck surgery, parathyroid tumors were identified in eight by either US or double-tracer scintigraphy. Preoperative parathyroid imaging with double-tracer scintigraphy and high-resolution US is suggested for patients with hyperparathyroidism, particularly in those patients who have had previous parathyroid surgery. 相似文献