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71.
The behavior of B, Cr, Se, As, Pb, Cd, and Mo in the leachates generated from two combustion residues, coal-fired power plant fly ash and municipal solid waste incineration ash, during precipitation of ettringite is presented. Experiments also were performed using modeled waste leachates as well as controlled solutions containing all the investigated elements. Moreover, to determine the possible effect of pH, lime treatment was conducted using the waste and modeled leachates. Results indicated the removal of B, Se, and Cr from the leachates because of incorporation of their oxyanions in the ettringite structure. The removal of B could further be explained by considering the structure of ettringite and monosulfoaluminate. The removal of Pb also occurred, probably because of lime-induced precipitation of Pb(OH)2. Similarly, the removal of As was observed as a result of lime-induced precipitation of Ca3(AsO4)2 and incorporation into the ettringite structure. On the other hand, the precipitation of ettringite did not reduce the concentrations of Mo and Cd because of the complex nature of these elements in the leachates. The results also suggest that the presence of high amounts of constituents such as Cl-, an alkali metal in the solution, also affected ettringite precipitation behavior. Moreover, elemental speciations as well as the presence of other constituents in the solution affected the incorporation by ettringite.  相似文献   
72.
AIM: To investigate macular function and morphology after surgical removal of idiopathic epiretinal membrane (IEM) with and without assistance of indocyanine green (ICG). METHODS: A retrospective study as a consecutive case series, of 39 patients with IEM. 39 patients, 23 female, 16 male, mean age 67 years, underwent standard three port pars plana vitrectomy with removal of epiretinal membrane. Two groups of patients were consecutively operated: in 20 patients ICG 0.1% in glucose 5% was used to stain the epiretinal membrane. 19 patients underwent the identical procedure but without use of ICG. Postoperative follow up was 1-92 months (mean 15.5 months). Functional outcome was assessed with subjective improvement, best corrected visual acuity (BCVA), Amsler grid test, 10 degrees and 30 degrees automated perimetry (Heidelberg visual field analyser) (HFA), and Goldmann kinetic perimetry. Macular morphology was assessed with stereoscopic biomicroscopy and optical coherence tomography (OCT). The main outcome measures were macular function as determined by BCVA, presence of visual field defects, and metamorphopsia as determined by Amsler grid test, macular morphology as determined by slit lamp biomicroscopy, and OCT. RESULTS: BCVA improved in 28 patients, remained unchanged in eight patients, and decreased in three patients. Improvement of BCVA was statistically significant in both groups (p = 0.003). Mean BCVA in patients operated with ICG improved from 0.33 preoperatively to 0.53 postoperatively. Mean BCVA in patients operated without ICG improved from 0.32 preoperatively to 0.54 postoperatively. Reduction of macular oedema as measured by OCT was statistically significant in both groups (p<0.01). There was no statistically significant difference in postoperative BCVA, macular oedema as measured by OCT, postoperative Amsler grid test, and subjective improvement between the two groups. The incidence of residual or recurrent epiretinal membrane was greater in the group operated without ICG (p = 0.014). Visual field defects were detected in one patient operated with ICG and in three patients operated without ICG. CONCLUSIONS: Removal of epiretinal tissue with or without assistance of ICG improved visual function and reduced macular oedema in most patients. Adverse effects clearly attributable to the use of ICG were not observed but further investigation is warranted.  相似文献   
73.
目的比较两种脑出血(ICH)动物模型磁共振成像(MRI)的差异,并对其分子机制进行探讨。方法将胶原酶和自体血注入大鼠尾状核建立脑出血模型,分别于术后6h、12h、1d、2d、3d和7d进行磁共振成像扫描,观察两组脑出血模型血肿体积的大小;运用干湿重法、伊文思蓝(EB)测定法和免疫印迹分别检测两组脑出血模型的脑含水量(BWC)、血脑屏障(BBB)通透性和AQP4的表达变化。结果胶原酶模型组的血肿体积在脑出血后1d达到最大并持续至3d,自体血组的血肿体积在12h达到最大;胶原酶模型组的BWC在1d达到高峰并持续至3d,而自体血组BWC在2d逐渐降低;胶原酶模型组的EB含量在12h达到高峰并持续至2d,而自体血组EB含量在1d逐渐下降;两组模型的AQP4表达量在6h开始升高,1d达到高峰,2d逐渐降低。两组模型比较具有统计学差异(P<0.05)。结论胶原酶对BBB和细胞外基质的破坏以及AQP4的表达变化是两组脑出血模型血肿体积出现差异的重要原因。  相似文献   
74.
Gastric tuberculosis is rare and usually presents as an ulcerated lesion or gastric outlet obstruction. Rarer presentations include massive gastrointestinal bleed and gastric perforation. A case of gastric tuberculosis presenting as linitis plastica is reported here. This is the first such case report. The patient was a young woman who presented with non-specific abdominal pain and significant weight loss. The gastric mucosa appeared oedematous and hyperaemic and there was spontaneous oozing of blood on upper gastrointestinal endoscopy. Computed tomography of the abdomen revealed diffuse thickening of the gastric wall. The diagnosis was confirmed by the presence of caseating granulomas with acid fast bacilli in the endoscopic biopsy specimen. The patient showed significant clinical improvement on four-drug anti-tuberculous treatment.  相似文献   
75.
目的探讨移植转染两种不同基因的骨髓间充质干细胞移植治疗大鼠心肌梗死的作用。方法分离、扩增培养大鼠骨髓间充质干细胞;ELISA检测细胞上清液ADM或HGF的含量;制备大鼠心肌梗死模型,心肌局部注射移植经DAPI标记的MSCs;多普勒超声检测大鼠心功能;荧光显微镜观察细胞存活及分布;免疫组化检测新生血管密度及移植细胞在心梗区的分化。结果转染Ad-ADM或Ad-HGF后,MSCs可有效表达ADM或HGF;与单纯MSCs组相比,两基因组细胞均表达TNI,均有connexin 43的表达增加(P<0.05),心梗区新生血管密度增高(P<0.01),左室射血分数(EF)增加(P<0.01);两组间各指标无差别。结论不同基因修饰的MSCs移植均可增强单纯MSCs对心肌梗死大鼠的治疗作用。  相似文献   
76.
Resistance and intolerance to imatinib are of particular clinical relevance to Asian patients because of their lower body surface area. Dasatinib is 325-fold more potent than imatinib in inhibiting BCR-ABL in vitro and is indicated for the treatment of chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute lymphoblastic leukemia resistant or intolerant to imatinib. Data from a series of phase I/II research trials were analyzed to compare the efficacy, safety and pharmacokinetic profile of dasatinib 70 mg twice daily in Asian and non-Asian patients. Results from 55 Asian and 615 non-Asian patients demonstrated that the efficacy and safety of dasatinib was comparable. Dasatinib was well tolerated, with no observed toxicities exclusive to Asian patients. A higher incidence of adverse events and lower rate of response observed among Asian patients with myeloid blast phase CML reflected the aggressive nature of the disease. Analyses of noncompartmental pharmacokinetics (5 Asian and 49 non-Asian patients) and population pharmacokinetics (17 Asian and 382 non-Asian patients) were also comparable. The efficacy, safety and pharmacokinetic profile of dasatinib 70 mg twice daily is similar in Asian and non-Asian patients with CML. Dasatinib is therefore an important therapeutic option for this patient population.  相似文献   
77.
Extended Spectrum Beta Lactamases (ESBL) are enzymes produced in some gram negative bacilli that mediate resistance to extended spectrum cephalosporins. 683 clinical isolates of Escherisia coli and Klebsiella pneumoniae were studied for their capacity to produce ESBL. Isolates showing resistance to at least two of the third generation cephalosporins were studied for ESBL production by Jarlier technique and combination disc methods. Out of the 457 E. Coli and 226 Klebsiella pneumoniae isolated in Assam Medical College, 29.76% and 53.1% were resistant to two cephalosporins of which 29.41% and 29.16% strains showed production of ESBL. However, 6 (4.41%) and 16 (13.34%) strains additionally showed production of ESBL when tested with combination disc method. Though the Jarlier technique is popular, for detection of ESBL, yet false negative results warrants for alternative method. In the absence of molecular detection methods in routine clinical microbiology laboratory, combination disc method appears to be a better option.  相似文献   
78.
目的探讨贺州市53例HIV感染者皮肤黏膜疾病及性传播疾病的病种分布、临床表现以及经性途径感染艾滋病变化的特点。方法回顾分析53例HIV感染者在门诊就诊期间皮肤黏膜及性传播疾病的种类、特征及实验室检查资料。结果 HIV感染者传播途径以性传播者占84.91%;皮肤黏膜损害复杂,以真菌、病毒感染等为主;疾病种类依次为性病、带状疱疹、湿疹、银屑病、泛发体癣等8种;有2种以上皮肤黏膜疾病者8例(15.09%);性传播疾病以早期梅毒为主13例(24.53%)。结论 HIV感染者皮肤黏膜损害以真菌、感染最多,性传播途径是HIV感染的主要途径之一,泛发的皮肤黏膜病变和合并性病感染可作为诊断HIV感染的依据之一。  相似文献   
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