全文获取类型
收费全文 | 15895篇 |
免费 | 1099篇 |
国内免费 | 499篇 |
专业分类
耳鼻咽喉 | 99篇 |
儿科学 | 263篇 |
妇产科学 | 258篇 |
基础医学 | 1323篇 |
口腔科学 | 499篇 |
临床医学 | 2109篇 |
内科学 | 2812篇 |
皮肤病学 | 254篇 |
神经病学 | 805篇 |
特种医学 | 320篇 |
外国民族医学 | 1篇 |
外科学 | 1559篇 |
综合类 | 1819篇 |
现状与发展 | 3篇 |
预防医学 | 759篇 |
眼科学 | 107篇 |
药学 | 3505篇 |
6篇 | |
中国医学 | 575篇 |
肿瘤学 | 417篇 |
出版年
2023年 | 292篇 |
2022年 | 524篇 |
2021年 | 751篇 |
2020年 | 584篇 |
2019年 | 506篇 |
2018年 | 472篇 |
2017年 | 451篇 |
2016年 | 413篇 |
2015年 | 503篇 |
2014年 | 781篇 |
2013年 | 1053篇 |
2012年 | 778篇 |
2011年 | 911篇 |
2010年 | 685篇 |
2009年 | 596篇 |
2008年 | 617篇 |
2007年 | 669篇 |
2006年 | 546篇 |
2005年 | 462篇 |
2004年 | 451篇 |
2003年 | 389篇 |
2002年 | 322篇 |
2001年 | 282篇 |
2000年 | 264篇 |
1999年 | 222篇 |
1998年 | 214篇 |
1997年 | 220篇 |
1996年 | 203篇 |
1995年 | 214篇 |
1994年 | 200篇 |
1993年 | 185篇 |
1992年 | 166篇 |
1991年 | 178篇 |
1990年 | 195篇 |
1989年 | 171篇 |
1988年 | 143篇 |
1987年 | 147篇 |
1986年 | 153篇 |
1985年 | 201篇 |
1984年 | 188篇 |
1983年 | 135篇 |
1982年 | 203篇 |
1981年 | 129篇 |
1980年 | 134篇 |
1979年 | 97篇 |
1978年 | 75篇 |
1977年 | 90篇 |
1976年 | 71篇 |
1975年 | 63篇 |
1974年 | 47篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
H W Peng T S Su S H Han C K Ho C H Ho K N Ching B N Chiang 《Journal of medical virology》1988,24(4):405-412
In order to study the prevalence of hepatitis B virus (HBV) in the adult population of Taiwan, we screened for the presence of HBV DNA in 205 blood samples from adult (20-59-year-old) volunteers. According to the serological markers of HBV, samples were divided into three groups: group I (173 subjects) was negative for both HBsAg and HBeAg; group II (14 subjects) was positive for both HBsAg and HBeAg; and group III consisted of 18 subjects who were HBsAg-positive but HBeAg-negative. Plasma HBV DNA was not detected in group I, but it was found in 85.7% and 11.8% of samples in group II and group III, respectively. A free-form HBV DNA was found in 14.3% of the leukocyte samples in group II. Furthermore, an integrated form of HBV DNA was detected in the leukocytes of two cases of group I who remained healthy based on clinical data. HBV DNA was also detected in the spermatozoa and liver cells of one of the cases. 相似文献
102.
J. Caverzasio H. Murer H. Fleisch J. -P. Bonjour 《Pflügers Archiv : European journal of physiology》1982,394(3):217-221
Recent clearance studies have demonstrated that the maximal tubular reabsorption of inorganic phosphate (Pi) per ml of glomerular filtrate (max. TRPi/ml GF) of the whole kidney is markedly lower in adult than in young growing rats fed either normal (0.8 g%) or low (0.2 g%) phosphorus diet. In addition, in adult rats clearance studies indicate that enhancement of max. TRPi/ml GF is observed 21 days but not 8 days after starting the low (0.2%) phosphorus diet. In the present work we have studied in the same experimental condition the Na+-dependent Pi uptake in brush border membrane vesicles (BBMV) isolated from renal cortex of either young growing or adult rats. The results of this study indicate that under the low (0.2%) but not under the normal (0.8%) phosphorus diet the Na+-dependent Pi uptake by BBMV was significantly depressed in adult as compared to young growing rats. In adult rats the Pi transport response to Pi restriction monitored at the brush border membrane level was different from that observed by clearance studies in the whole kidney. Indeed, the Pi uptake by BBMV was already enhanced after 8 days of Pi restriction and it did not increase further when studied 21 days after starting the low (0.2%) phosphorus diet. These results suggest that the regulation of the overall transfer of Pi across the renal epithelium may involve other additional modulating factors than the Na+-dependent Pi transport system present in the luminal membrane of the proximal tubule. 相似文献
103.
104.
Isolation of human immunodeficiency virus (HIV) from plasma during primary HIV infection 总被引:13,自引:0,他引:13
Jan Albert Hans Gaines Anders Snnerborg Gunnel Nystrm Pehr Olov Pehrson Francesca Chiodi Madeleine von Sydow Lars Moberg Knut Lidman Bertil Christensson Birgitta sj Eva Maria Feny 《Journal of medical virology》1987,23(1):67-73
Human immunodeficiency virus (HIV) has been isolated from plasma in 6 of 7 patients showing clinical symptoms of a primary HIV infection. Parallel cultures from peripheral blood mononuclear cells (PBMC) yielded virus in 5 patients. In one case, virus could only be isolated from the cerebrospinal fluid but not from peripheral blood. Detectable viremia was transient and preceded the appearance of HIV specific antibodies. After cessation of acute symptoms, the frequency of HIV isolations was similar to that of asymptomatic carriers (23 and 26%, respectively). The role of the immune response in terminating detectable viremia remains to be established. 相似文献
105.
目的:探讨载脂蛋白H(apolipoprotein H,apoH)基因第8外显子G1025C(Try316Ser)多态性与长沙地区汉族人脑卒中的关系及其对血 脂的影响。方法:采用PCR-单链构象多态技术和DNA直接测序法检测长沙地区汉族260例脑卒中患者、20个脑卒中家系成员和100名健康对照者的apoH基因第8外显子G1025C(Try316Ser)多态性;酶联免疫吸附法检测抗磷脂抗体水平;酶法测定总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C),免疫比浊法测定apoA-I及apo B100,酶联免疫吸附法测定脂蛋白a血清水平。结果:长沙地区汉族人apoH基因G1025C(Try316Ser)多态存在GG、GC两种基因型,脑卒中组及其各亚组G1025C(Try316Ser)多态基因频率分布与对照组比较差异无显著性(P>0.05);分析不同基因型对血脂、脂蛋白水平的影响,发现脑梗塞组和对照组GC基因型血清TG水平均明显高于GG基因型(P<0.05)。结论:长沙地区汉族人apoH基因G1025C(Try316Ser)多态性可能与脑卒中的易患性无关,但与血脂代谢有一定关联。 相似文献
106.
Savchenkova AP Dudnik LB Pogoretskaya IL Solov'eva NP Pokrovskaya MA Aseichev AV Drinitsyna SV Azizova OA Lopukhin YM 《Bulletin of experimental biology and medicine》2003,135(1):29-33
In patients with coronary heart disease oxidizability of lipids during Cu2+-induced oxidation of blood plasma inversely correlated with fibrinogen content. A positive correlation was found between the amount of lipid peroxidation products in the plasma from these patients and fibrinogen content. The increase in fibrinogen content was associated with high levels of total lipids and triglycerides and low concentration of high-density lipoprotein cholesterol. In vitro experiments demonstrated that fibrinogen reduces oxidizability of blood plasma. Our results suggest that the decrease in lipid oxidizability at high concentration of fibrinogen in patients with coronary heart disease is related to predominant oxidation of fibrinogen and its competition with plasma lipids during Cu2+-induced oxidation. 相似文献
107.
Sengoku K Takuma N Miyamoto T Horikawa M Ishikawa M 《Human reproduction (Oxford, England)》2004,19(3):639-644
BACKGROUND: We investigated whether integrins are required forthe human spermoocyte binding and fusion processes. METHODS:The expression of several integrin subunits at the human oocyteplasma membrane was investigated using immunofluorescence microscopy,and the functional role of integrins expressed at the humanoocyte surface in spermoocyte interaction was studiedusing a zona-free human oocyte binding and fusion assay. A totalof 144 unfertilized oocytes were stained with anti-integrinantibodies and 147 zona-free unfertilized oocytes were inseminatedin the presence of various anti-integrin antibodies that wereexpressed in oocyte plasma membrane. RESULTS: The antibodiesof six integrin subunits (2, 3, 5, 6, V, M) and six integrinsubunits (1, 2, 3, 4, 5, 6) were bound to the surface of fixedunfertilized oocytes. In contrast, the presence of 1 and 4 subunitscould not be verified. The human spermoocyte bindingwas only partially inhibited by blocking antibodies of 2, 3,5, 6, V, M, 1, 2 and 3 with a maximum of 55% inhibition, butantibodies of 4, 5 and 6 showed no effect on spermoolemmalbinding. A similar reduction of the number of fused sperm wasobserved. However, the ratio of fused sperm to total sperm (boundand fused) was not impaired by all integrin antibodies, suggestingthat integrins had no role in the spermoolemmal fusionprocess. CONCLUSIONS: These results suggest that one of thebinding mechanisms can be inhibited by integrin antibodies butthat this mechanism does not play an essential role in the humanspermoolemmal binding and fusion processes. The othermechanisms, insensitive to integrins, may involve both bindingand fusion processes in human oocytes. 相似文献
108.
109.
Genetics of the low density lipoprotein receptor: 总被引:1,自引:0,他引:1
Fibroblast association (plasma membrane binding plus intracellular accumulation) and degradation of radioiodinated low density lipoprotein (125I-LDL) index plasma membrane LDL receptor activity. Cultured fibroblasts from 23 subjects affected with familial hypercholesterolemia (HC) and from 95 subjects without HC (non-HCs) were tested for 125I-LDL association and degradation. Both LDL receptor activity indices were twice as high in non-HC and HC heterozygous cell strains. This is compatible with a major gene effect on LDL receptor activity. However, a considerable overlap between non-HC and HC heterozygous values was found in the 125I-LDL association assay [median (range) 970 (330-2500), and 450 (250-490), respectively] and in the degradation assay [median (range) 810 (280-2020), and 470 (160-790), respectively]. The values are expressed as ng 125I-LDL X mg cell protein-1 X 4.5 h-1. These great overlaps in the LDL receptor activity indices support the view that the influence of LDL receptor activity on the HC phenotype may be smaller than believed previously. Furthermore, for the diagnosis of HC, these LDL receptor activity assays are far more expensive and have less sensitivity and specificity than simple serum cholesterol determination. The LDL receptor-dependent 125I-LDL association values for the HC heterozygous individuals clustered into four groups. Family data supported the hypothesis that this variation could be due to four different LDL receptor variants, each coded for by different alleles at the LDL receptor locus. If confirmed, this finding may have implications for the understanding of the variable expression of HC and also of the genetic impact on lipoprotein metabolism and susceptibility to atherosclerosis in non-HCs. 相似文献
110.
观察血浆置换、内科治疗对中晚期重型乙型病毒性肝炎生存率的影响,探索中晚期重型肝炎的治疗方法。方法观察在内科治疗基础上给予血浆置换患者的肝功能、并发症及疾病的转归,与同期仅予内科综合治疗的患者相比较,对相应的临床资料进行统计学分析,从而了解两种治疗方法的疗效。结果血浆置换组36例,18例好转、18例死亡,内科治疗组32例,13例好转、19例死亡,两组之间患者生存情况无统计学差异;肝功能指标(ALT、AST、SB、ALB、TC、ChE和凝血酶原时间(PT)也无统计学差异。结论与内科治疗相比较,在其基础上给予血浆置换并不能提高中晚期重型病毒性肝炎生存率;中晚期重型肝炎患者的预后决定于其肝功能衰竭的程度。 相似文献