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81.
黄芪多糖对LAK细胞毒的增强作用 总被引:7,自引:0,他引:7
本文采用乳酸脱氢酶(LDH释放法研究了黄芪多糖(APS)对淋巴因子活化的杀伤细胞(LAK)的增强作用。结果表明:APS具有明显的增强LAK细胞毒作用,有效剂量范围为0.001mg/ml~0.01mg/ml,在0.01mg/ml呈最大的增强作用,为原LAK细胞毒性的3倍。同时也证实黄芪水煎剂本身也具有一定的增强作用。 相似文献
82.
R. B. Zotz G. Giers B. Maruhn-Debowski & R. E. Scharf 《British journal of haematology》1997,96(1):198-203
Genotyping of platelet alloantigens with the possibility of using any type of cellular material as a source of DNA has become a preferred procedure, particularly in thrombocytopenic patients when platelet counts are too low for phenotyping. Recently human platelet antigen 1 (HPA-1) has been identified as an inherited risk factor for coronary thrombosis. The different detection methods currently used have disadvantages for large-scale DNA diagnosis, including the need for electrophoresis (allele-specific restriction enzyme analysis, amplification with sequence-specific primers) or the potential risk of reduced specificity (allele-specific oligonucleotide hybridization). In this report we describe the adaptation of an automated oligonucleotide ligation assay to genotype HPA-1 in polymerase chain reaction (PCR)-amplified DNA samples. HPA-1a and HPA-1b phenotypes corresponded to the results of the different genotyping assays. The genotypes determined with the ELISA-based PCR-oligonucleotide ligation assay were in 100% concordance with the results obtained by conventional allele-specific restriction enzyme site analysis and PCR amplification with sequence-specific primers. The automated oligonucleotide ligation assay provides a rapid, reliable, nonisotopic method to genotype human platelet antigens that can rapidly be applied to large population screening. 相似文献
83.
为探讨用ELISA法(酶联免疫吸附试验)检测血清抗PPD(结核菌素纯蛋白衍生物)IgG抗体对儿童结核的诊断意义,对42例儿童结核、30例儿童肺炎及16例健康对照者进行了检测,阳性率分别为92.85%、6.66%、6.25%。结核病例经六个月正规化疗后,阳性率明显降低,说明此项检测可做为一项诊断儿童结核及评价疗效的指标。 相似文献
84.
T. N. RAMUTHAGA M. s. BORNMAN M. F. MAHOMED D. BOOMKER A. S. GREEF H. H. CREWE-BROWN S. REIF 《International journal of andrology》1994,17(1):9-12
Swabbing the urethrae of men has been the traditional approach for collecting specimens for detection of Chlamydia trachomatis . Recently, however, urine testing using enzyme immunoassay has yielded promising results. A total of 105 patients attending the Andrology Clinic at Ga Rankuwa Hospital, Medunsa were included in the study. These patients were asymptomatic and had no urethral discharge. Three endo-urethral swabs and first-catch urine were collected fiom each patient. The urethral swabs were used for enzyme immunoassay (EIA) (IDEIA 111), tissue culture and direct immonufluorescent antibody (DFA) test (IMAGEN) to detect C. trachomatis . In addition about 15–30 ml of first-catch urine, or urine collected at least 2h after the previous micturition, was collected for each patient for EIA testing. Fifteen (14.3%) of 105 patients were positive on urethral swab EIA, in comparison with the DFA test in which 14 (13.3%) were positive. Eight (7.8%) were positive in tissue culture. Urine EIA was positive in 17 (16.2%) patients, of whom five (4.8%) were positive in urine EIA only. All EIA positive urines were confirmed by DFA. We recommend that first-catch urine or urine collected at least 2h after the previous micturition in infertile males may be considered a suitable alternative to urethral swab for chlamydial diagnosis because it is noninvasive and nontraumatic. 相似文献
85.
氯喹敏感与抗性株恶性疟原虫对青蒿琥酯、克林霉素及其联用的体外敏感性 总被引:3,自引:0,他引:3
目的 为了解氯喹敏感和抗性株恶性疟原虫对青蒿琥酯、克林霉素及其二联用的敏感性。方法 运用Rieckmann体外微量法测定原虫对药物的敏感性。结果 氯喹敏感株恶性疟原虫对青蒿琥酯、克林霉素及青/克联用的ID50分别为2.8、3784.7及6.4/2046.6nmol/L;抗性株原虫对上述药物的ID50分别为8.1、1652.1及2.35/1409.4nmol/L。结论 抗氯喹恶性疟原虫对克林霉素无交叉抗性。青蒿琥酯与克林霉素联用在体外测定中,其抗疟作用对抗性株明显优于敏感株。 相似文献
86.
吲哚美辛对人结肠癌HCT116和SW480细胞的影响 总被引:3,自引:0,他引:3
目的:探讨吲哚美辛对人结肠癌HCT116和SW480细胞的影响。方法:体外培养细胞,采用MTT法分别检测吲哚美辛作用后两系细胞的生长情况,计算半抑浓度(IC50);体内建立裸鼠皮下移植瘤模型,喂服吲哚美辛3 mg/(kg·d)共4周,隔日测瘤结节体积及鼠重,评价吲哚美辛的抑瘤效果。结果:吲哚美辛作用于结肠癌HCT116和SW480细胞48 h后,细胞的生长均受到明显抑制,呈剂量依赖效应,IC50分别为 (318.2±12.7) μmol/L和 (701.4±29.5) μmol/L;吲哚美辛显著减慢裸鼠皮下移植瘤的生长,用药4周后抑瘤率达44.6%,未见明显毒性反应。结论:吲哚美辛能抑制不表达环氧合酶的人结肠癌细胞(HCT116和SW480)生长,间接说明其抗癌作用不完全依赖环氧合酶途径,还存在其它的可能机制。 相似文献
87.
Jonas Bergstrm Mahmood Ahmed Jian Li Tashfeen Ahmad Andris Kreicbergs Mariana Spetea 《Journal of orthopaedic research》2006,24(6):1193-1199
Using immunohistochemical and biochemical techniques, the occurrence of endogenous opioid peptides and their receptors in normal rat bone and joint tissues was investigated. Opioid receptors were detected, quantified, and characterized in homogenates from capsule/synovium and periosteum using radioligand binding assays. Receptor binding of the nonselective opioid [3H]naloxone to tissue homogenates was stereospecific and saturable, showing similar characteristics to that of brain tissue, although with lower binding capacities. By immunohistochemistry, the neuronal occurrence of four different enkephalins was demonstrated in synovium, bone marrow, periosteum, and juxta-articular bone, whereas no neuronal dynorphin immunoreactivity was detected. Double-staining studies disclosed that enkephalins coexisted with substance P in primary afferent fibers. The applied techniques can be used to assess changes in the distribution of endogenous opioids and their receptors in joint tissues in conditions associated with pain and inflammation. The endogenous opioid system now demonstrated might be targeted and exploited therapeutically to obtain peripheral control of symptoms in joint disorders. 相似文献
88.
本文报道用550型全自动生化分析仪,以速率法测定尿NAG活性及本室尿NAG活性的正常参考范围;并对可能影响尿NAG活性的尿PH,尿素浓度等进行了干扰试验及分析。 相似文献
89.
甘草甜素和甘草酸单铵促进IL-2增强NK活性的研究 总被引:1,自引:0,他引:1
本实验采用乳酸脱氢酶释放法研究甘草甜素和甘草酸单铵对人外周血NK细胞活性的影响。结果表明,甘草甜素和甘草酸单铵本身无增强NK细胞活性的作用,但可明显促进IL-2增强NK活性,这种增强作用与甘草甜素和甘草酸单铵的浓度有关。 相似文献
90.
Humoral immunity to Malassezia furfur serovars A, B and C in patients with pityriasis versicolor, seborrheic dermatitis and controls 总被引:2,自引:0,他引:2
H. R. Ashbee A. Fruin K. T. Holland W. J. Cunliffe E. Ingham 《Experimental dermatology》1994,3(5):227-233
Abstract This study examined the humoral immune responses to Malassezia furfur serovars A, B and C of 10 patients with pityriasis versicolor, 10 patients with seborrheic dermatitis and 20 age- and sex-matched controls. A transferable solid-phase ELISA was used to determine titres of total Igs, IgM, IgA and IgG specific to M. furfur serovars A, B and C. The results demonstrated that patients with seborrheic dermatitis had a significantly higher litre of total Igs to serovar A than patients with pityriasis versicolor; and that patients with seborrheic dermatitis had a significantly higher litre of IgA to serovar C than patients with pityriasis versicolor. The litres of total Igs for controls and patienls with seborrheic dermatitis were significantly lower to serovar B than to serovar C. A modified TSP ELISA was used to determine the titres of the IgG subclasses. Titres of IgG 1,3,4 to serovar B were significantly higher in seborrheic dermatitis patients than pityriasis versicolor patients and litres of IgG3, to serovar A were significantly higher in seborrheic dermatitis patients than pityriasis versicolor patients. However, despite the differences between the patient groups, none of these results was significantly different to those of controls. Thus, this study did not demonstrate any differences in humoral immunity of patients suffering from Malassezia-associated dermatoses when compared to normal controls. These results may suggest that the humoral immune response to M. furfur is not related to the pathogenesis of Malassezia-associated dermatoses, but simply to the carriage of M. furfur on the skin. 相似文献