全文获取类型
收费全文 | 2304篇 |
免费 | 166篇 |
国内免费 | 105篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 70篇 |
妇产科学 | 27篇 |
基础医学 | 362篇 |
口腔科学 | 31篇 |
临床医学 | 233篇 |
内科学 | 452篇 |
皮肤病学 | 29篇 |
神经病学 | 86篇 |
特种医学 | 56篇 |
外国民族医学 | 1篇 |
外科学 | 130篇 |
综合类 | 390篇 |
预防医学 | 106篇 |
眼科学 | 9篇 |
药学 | 201篇 |
中国医学 | 71篇 |
肿瘤学 | 305篇 |
出版年
2023年 | 23篇 |
2022年 | 36篇 |
2021年 | 41篇 |
2020年 | 55篇 |
2019年 | 47篇 |
2018年 | 62篇 |
2017年 | 67篇 |
2016年 | 52篇 |
2015年 | 57篇 |
2014年 | 93篇 |
2013年 | 128篇 |
2012年 | 103篇 |
2011年 | 146篇 |
2010年 | 100篇 |
2009年 | 106篇 |
2008年 | 109篇 |
2007年 | 125篇 |
2006年 | 103篇 |
2005年 | 88篇 |
2004年 | 85篇 |
2003年 | 83篇 |
2002年 | 76篇 |
2001年 | 65篇 |
2000年 | 87篇 |
1999年 | 81篇 |
1998年 | 64篇 |
1997年 | 58篇 |
1996年 | 52篇 |
1995年 | 36篇 |
1994年 | 43篇 |
1993年 | 26篇 |
1992年 | 23篇 |
1991年 | 27篇 |
1990年 | 21篇 |
1989年 | 15篇 |
1988年 | 15篇 |
1987年 | 9篇 |
1986年 | 14篇 |
1985年 | 38篇 |
1984年 | 13篇 |
1983年 | 13篇 |
1982年 | 21篇 |
1981年 | 19篇 |
1980年 | 16篇 |
1979年 | 9篇 |
1978年 | 7篇 |
1977年 | 8篇 |
1976年 | 7篇 |
1975年 | 2篇 |
1974年 | 1篇 |
排序方式: 共有2575条查询结果,搜索用时 15 毫秒
1.
2.
目的探讨粒细胞集落刺激因子(rhG-CSF)对下肢缺血模型血管新生的影响。方法制作兔左下肢缺血模型,术后随机分为rhG-CSF治疗实验组(n=24)和对照组(n=24);应用流式细胞学技术、动脉造影、免疫组织化学染色检查,比较两组外周血CD34 细胞的含量、缺血下肢侧枝血管计数及肌肉毛细血管密度。结果治疗后3 d实验组CD34 含量(%)为(0.7150±0.0873)明显高于对照组(0.3983±0.0853),差异有统计学意义(P<0.01);实验组在第15、30天时侧枝血管计数(6.33±0.82、9.17±0.75)均高于对照组(3.33±0.52、4.17±0.75)(P<0.01);第40天实验组内收肌毛细血管密度平均为8.5/HP,明显高于对照组4.2/HP(P<0.01)。结论rhG-CSF可以增加兔缺血下肢的毛细血管数量,有促进血管新生的作用。 相似文献
3.
用小鼠胎肝细胞体外血浆凝块培养红系集落(Erythroid colong formig unit inculturc,E-CFUc)方法,以红细胞生成素(Erythropoietin,EPO)850323为标准试剂,测定正常人、贫血病人血清EPO浓度。实验用妊娠13~15d小鼠胎肝细胞。血清均经透析处理,培养液中加量最大不超过10%。EPO(850323)在培养液中浓度为2.5~100mU/ml。血清EPO(mU/ml)测定结果:28例正常人为48.O±17.7,12例再生障碍性贫血病人为946~>10000,1例巨幼细胞性贫血病人为500,1例缺铁性贫血病人为400和18例慢性肾功能衰竭病人则为94.2±87.6。结果表明:贫血病因对血清EPO浓度有影响。 相似文献
4.
Takashi Ito Kazuo Shimamura Kiyoshi Shoji Akira Akatsuka Yasuyoshi Kiryu Norikazu Tamaoki Yoshiyuki Osamura 《Virchows Archiv : an international journal of pathology》1993,422(6):487-490
A rare case of urinary bladder carcinoma with granulocyte colony stimulating factor (G-CSF) production was reported. In an 83-year-old female, marked neutrophilia in the peripheral blood decreased from 132,500/mm3 to 3,300/mm3 after tumour resection. The tumour was a transitional cell carcinoma. The serum G-CSF level reduced from 238 pg/ml pre-operatively to normal (60 pg/ml) after the operation. Immunohistochemical investigation of the resected tumour with monoclonal antibody specific for G-CSF revealed positive staining in the carcinoma cells, confirming G-CSF secretion. 相似文献
5.
人癌干细胞集落形成测定常用双层琼脂平皿法。新法系采用园形玻璃毛细管法培养!可
以减少细胞用量及药物消耗。管内径为1.3mm,管长9.75cm,内盛15.000有核细胞/50μl,培养7~
14天。50例肿瘤活检标本生长成功率为88%,并可供化疗药物敏感性试验用。这种微量化检测具有
独特的优点,便于推广应用。 相似文献
6.
The behavioral genetics of colony defense in honeybees: Genetic variability for guarding behavior 总被引:3,自引:1,他引:2
Guard honeybees stand at the entrance of colonies and facilitate the exclusion of nonnestmates from the colony. In this study, we examined the hypothesis that genetic variability among individuals in colonies might explain variability in guarding activity. To do this, we cross-fostered honey bees between colonies with high-defensive responses and colonies with low-defensive responses in alarm pheromone tests. Individuals from high-defensive colonies were more likely to guard in their own colonies (controls) than cross-fostered bees from low-defensive colonies. Cross-fostered high-defensive bees also were more likely to guard in low-defense colonies. These results support the hypothesis that interindividual differences in guarding behavior are at least partially under genetic control. A positive correlation between number of guards and response to alarm pheromone demonstrates a link between behaviorally separated components of the overall defensive response.This work was supported by NSF Grant BNS 8605604. 相似文献
7.
在标记脐血造血祖细胞表面抗原(HPCA),CD34中,比较抗-HPCA-2-FITC和Tk3(纯抗体)标记的CD(34+)细胞在流式细胞仪分析中的荧光特征及两种单抗标记的CD(34+)细胞与体外培养的粒单细胞集落形成单位(CFU-GM),红系爆发形成单位(BFU-E),和混合集落形成单位(CFU-Mix)的相关性。结果发现脐血有核细胞中,抗HPCA-2阳性细胞占1.05±0.72%(n=13),Tk3阳性细胞占2.06±1.25%(n=8),差别显著(P<0.05)。每毫升脐血两种抗体标记的细胞分别为96.56±56.64和231.40±163.93(P<0.05)。尽管HPCA-2阳性细胞与Tk3阳性细胞数量呈显著正相关(r=0.875,P<0.01),前者与CFU-GM,BFUE,CFU-Mix及集落总数CFUs均呈正相关,而后者仅与CFU-GM,CFUs相关。研究提示在检测造血祖细胞时,用抗-HPCA-2-FITC代替Tk3可降低假阳性,获得较好的OD(34+)细胞与CFU间的线性关系。 相似文献
8.
Rob Cincotta Alan Balloch Jack Metz Judith E. Layton Graham J. Lieschke 《American journal of hematology》1995,48(4):288-288
A patient with neutropenia and life-threatening infections secondary to T-γ lymphoproliferative disease, who did not respond to treatment with recombinant human G-CSF (filgrastim), was treated with filgrastim plus cyclosporine A (CyA). The patient achieved a good response in the absolute neutrophil count and subsequently required a dose reduction in the filgrastim. The patient was eventually discontinued from the CyA but continues on filgrastim alone. While on therapy, the large granular lymphocytes disappeared from the circulation and the beta-TCR rearrangement, which was present prior to beginning therapy, became undetectable. The patient had no significant toxicity to the CyA or the filgrastim and he has not experienced any serious infections or required hospitalization. Filgrastim has proven to be relatively nontoxic and of some benefit to patients with this disease and should probably be utilized first when treatment is necessary. However, if improvement is not observed, these findings suggest that a trial of the combination of CyA plus filgrastim may be beneficial. 相似文献
9.
F. DE ARRIBA M. L. LOZANO F. ORTUÑO I. HERAS J. M. MORALEDA & V. VICENTE 《British journal of haematology》1997,96(2):418-420
Thirty patients diagnosed with breast cancer were included in a prospective randomized study comparing the in vivo priming effect of bioequivalent doses of glycosylated (lenograstim) and nonglycosylated (filgrastim) rG-CSF administration. Analysis of the efficacy of equivalent biological doses of both rG-CSFs showed no significant differences either in the mobilization of the subpopulations of PBPC considered (CD34+ , CD34+ /38− , CD34+ /DR− ), the content of such CD34+ cell subsets in the leukapheresis product, or the cost of the mobilization and collection procedures between both recombinant molecules. These results suggest that priming with bioequivalent doses of the two commercially available forms of glycosylated or nonglycosylated rG-CSF has a similar in vivo effect on PBPC mobilization. 相似文献
10.
目的:利用粒细胞-巨噬细胞集落刺激因子(GM-CSF)作为基因佐剂,提高东部马脑炎病毒E2基因重组质粒的免疫效果.方法:分别扩增E2基因与GM-CSF基因,连接进入含有内部核糖体插入位点(IRES)的真核表达载体中,构建共表达质粒.Lipofectamine2000介导转染真核细胞BHK-21,反转录PCR检测E2和GM-CSF两个基因的转录,Western印迹法和间接免疫荧光法(IFA)检测细胞内E2基因表达产物的抗原性.通过肌肉注射免疫BALB/c小鼠,IFA法测定血清抗体效价,FACS测定免疫小鼠脾细胞中CD4 /CD8 淋巴细胞构成比,初步观察共表达质粒的免疫原性.结果:经酶切鉴定与序列测定证明重组共表达质粒中含有E2和GM-CSF两个基因且序列正确.转染细胞的反转录PCR可见E2和GM-CSF两个基因的转录.Western印迹结果可见转染细胞的裂解液在相对分子质量50 000位置有特异性条带.将转染细胞制成荧光抗原片,经IFA检测可见胞浆中出现特异荧光.免疫小鼠的最高血清抗体效价为1:160,但细胞免疫未观察到明显的提高.结论:构建的共表达质粒pE2-IRES-mGM-CSF具有良好的免疫原性,能有效刺激小鼠特异性体液免疫应答,提高了E2基因重组质粒诱导的血清抗体效价. 相似文献