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101.
目的:观察lrigl基因在食管鳞癌中的表达及意义.方法:采用RT.PCR检测36例食管鳞状细胞癌癌组织、相应的癌旁组织和远癌组织中lriglmRNA的表达情况.PCR产物经凝胶电泳,比较3种组织中ragl与GAPDH条带的灰度值之比,半定量分析IriglmRNA的表达水平.结果:36例食管癌组织中有15例(42%)lriglmRNA检测到阳性表达,21例(58%)lriglmRNA表达缺失,其阳性表达率低于相应的癌旁组织(92%)和远癌组织(100.0%,P〈0.05);癌组织中lriglmRNA表达水平(0.76±0.22)低于相应的癌旁组织(0.89±0.33)和远癌组织(1.13±0.40);随着肿瘤分化程度的升高,lriglmRNA在癌组织中的阳性表达率也增加(P〈0.05),但lriglmRNA表达缺失与食管癌临床分期(TNM),淋巴结有无转移和病理类型均无统计学差异(P〉0.05).结论:lriglmRNA在食管癌组织中存在表达缺失和低表达,提示Irigl基因在食管癌的发生发展中可能具有抑癌基因的作用. 相似文献
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103.
Bradyarrhythmias and Laparoscopy: A Prospective Study of Heart Rate Changes with Laparoscopy 总被引:1,自引:0,他引:1
Paul S. Myles DipRACOG DA 《The Australian & New Zealand journal of obstetrics & gynaecology》1991,31(2):171-173
Cardiac arrhythmias are a common complication of laparoscopy. Brady-arrhythmias (including asystole) may be life-threatening. The recent introduction of new shorter-acting muscle relaxants (atracurium and vecuronium), with their lack of vagolytic activity, may exacerbate this situation. At the Royal Women's Hospital there have been several episodes of severe bradyarrhythmias and/or asystole associated with these relaxants. This study evaluated heart rate changes in 49 women during laparoscopy: 47% of patients had arrhythmias, 30% of these being bradyarrhythmias. Nearly all the episodes occurred during carbon dioxide insufflation or with traction on pelvic structures. The life-threatening nature of this phenomenon should be understood by all anaesthetists and gynaecologists engaged in laparoscopic procedures. 相似文献
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106.
Di Pietro A Scoglio ME Anzalone C Calimeri S Lo Giudice D Marino A 《Annali di igiene : medicina preventiva e di comunità》2000,12(6):469-478
We sought to determine the effect of 26 multiple metals solutions, containing Cd, Pb, As and/or Ni, on the viability of Salmonella enteritidis. We used the direct viable count effected by immunofluorescence technique (IFA-DVC) in comparison with the culturable cell count. The metals concentrations were prepared considering the single as well as the overall limits provided by Italian regulation on the water pollution. The mixtures containing nickel showed always toxicity more elevated than other metal solutions tested. Thus we consider too high the nickel law limit. The interactions among the elements, causing generally toxicity decrease, are very well assessable by IFA-DVC test. This method permits to calculate the lethal concentrations of toxicants on bacteria that play a pivotal role on the ecosystem components. 相似文献
107.
Deicken RF Pegues MP Anzalone S Feiwell R Soher B 《The American journal of psychiatry》2003,160(5):873-882
OBJECTIVE: Previous studies attempting to identify neuropathological alterations in the hippocampus in bipolar disorder have been inconclusive. The objective of this study was to determine if the concentration of N-acetylaspartate, a neuronal and axonal marker, was lower in subjects with familial bipolar I disorder than in healthy comparison subjects, suggesting possible neuronal loss, neuronal dysfunction, or neuropil reduction in bipolar I disorder. METHOD: N-acetylaspartate, choline, and creatine in the right and left hippocampus were measured in 15 euthymic male patients with familial bipolar I disorder and 20 healthy male comparison subjects by using proton magnetic resonance spectroscopy ((1)H-MRS). RESULTS: Relative to the comparison group, the patients with bipolar I disorder demonstrated significantly lower concentrations of N-acetylaspartate and creatine but normal choline concentration in both the right and left hippocampus. There were no group or lateralized differences in the percentages of different tissue types within the MRS voxels, suggesting that the hippocampal N-acetylaspartate and creatine alterations were not an artifact of variations in tissue types represented in the voxels. There was also a significant negative correlation between N-acetylaspartate concentration in the right hippocampus and illness duration, after adjustment for the effects of age. CONCLUSIONS: This preliminary study provides support for the existence of neuronal loss, neuronal metabolic dysfunction, or interneuronal neuropil reduction in the hippocampal region in male patients with familial bipolar I disorder. The finding of normal hippocampal choline levels in these patients does not provide support for ongoing myelin breakdown or glial cell proliferation in this brain region in familial bipolar I disorder. The significant association between illness duration and N-acetylaspartate concentration in the right hippocampus supports the idea that neuronal pathology may increase with disease progression and that this effect may be lateralized, involving the right but not the left hippocampus. 相似文献
108.
目的构建可用于高通量筛选JAK/STAT6信号传导通路抑制剂的工程细胞株,建立稳定可靠的筛选方法。方法利用基因重组和转染技术,将STAT6特异性识别启动子IgE基因序列和虫荧光素酶报告基因联合插入pCMV质粒,脂质体法转染至HeLa细胞,经潮红霉素B抗性筛选及报告基因检测,得到稳定表达虫荧光素酶的工程细胞株。通过优化溶剂DMSO浓度,IL4作用浓度及孵育时间等筛选条件,建立了可靠的筛选方法,并在此基础上对1600种化合物进行了筛选。结果建立的筛选方法稳定可靠,系统Z′因子达到0.64。通过对1600种化合物的筛选,得到3个抑制效果较理想的化合物并测得其IC50值。结论所建立的高通量筛选方法可用于JAK/STAT6信号传导通路抑制剂的筛选。 相似文献
109.
Michaloudis D Fraidakis O Petrou A Farmakalidou H Neonaki M Christodoulakis M Flossos A Bakos P Melissas J 《Obesity surgery》2000,10(3):220-229
Background: The authors determined prospectively the safety of continuous spinal anesthesia combined with general anesthesia
and the efficacy of postoperative pain relief with continuous spinal analgesia for morbidly obese patients undergoing vertical
banded gastroplasty. Methods: 27 patients (13 men, 14 women) with a mean body mass index (BMI) of 50.4 ± 7.8 and several co-morbidities
were studied. All patients were anesthetized with the same anesthetic regimen, which included midazolam, fentanyl, propofol,
muscle relaxants, N2O, isoflurane and intrathecal bupivacaine. Postoperative pain relief was provided for 5 days and all patients received the
same regimen, which included intrathecal bupivacaine, fentanyl and intravenous tenoxicam. The intrathecal analgesic regimen
was administered continuously through a pump which had the facility of providing bolus doses when requested in predetermined
lockout intervals. Intra-operative monitoring included hemodynamic and respiratory parameters. Additional postoperative monitoring
included respiratory rate, degree of sedation, sensory level of anesthesia, motor response and intensity of pain. Results:
Intraoperative anesthetic technique was safe and provided satisfactory results in the immediate postoperative period. Furthermore,
the postoperative analgesia regimen provided effective analgesia in all patients.The mean doses of fentanyl and bupivacaine
infused intrathecally for the first 24 postoperative hours were 14.1 ± 2.0 μg.h-1 and 0.7 ± 0.1 mg.h-1 respectively, while the requirements of anal gesia decreased progressively with time. The technique provided effective analgesia
with low pain scores, which was reflected by ease in mobilizing and performing physical exercises with the physiotherapist.
Only minor complications related to anesthesia and analgesia were encountered. Conclusion: To our knowledge, this technique
of anesthesia and postoperative analgesia has not been described before in morbidly obese patients. This regimen merits further
controlled trials to establish its place in the perioperative management of morbidly obese patients. 相似文献
110.
Cytogenetic and molecular genetic analysis of tumorigenic human bronchial epithelial cells induced by radon alpha particles 总被引:4,自引:1,他引:4
To establish a cell culture model for lung carcinogenesis, independent
populations of the human papillomavirus 18-immortalized human bronchial
epithelial cell line BEP2D were treated with high linear energy transfer
radon-simulated alpha-particles, expanded and xenotransplanted into Nu/Nu
mice. Six independent cell lines were established from tumors that
developed from three separate radiation treatments as follows: treatment
(Tx) 1 (30 cGy--two doses), H2BT, Tx 2 (30 cGy-- single dose), R30T1L,
R30T2 and R30T3L, Tx 3 (30 cGy--single dose), H1ATN and H1ATBA1.
Cytogenetic analysis revealed common changes in all tumor lines: loss of
the Y chromosome (ch), one of three copies of ch8, one of three copies of
ch14, and one of two copies of ch4p16-pter and ch11p15-pter. Analysis of
polymerase chain reaction-amplified short tandem repeats of informative
loci confirmed the loss of chY in all lines and loss of heterozygosity
(LOH) at eight loci spanning the length of ch8 in all lines from Tx's 1 and
2. Our data support previous studies indicating the presence of tumor
suppressor genes on ch8. LOH also was confirmed on ch14 at locus D14S306 in
all cell lines from Tx 2 and in one of two lines from Tx 3. This region,
14q12-q13, may contain changes in one of the five known somatostatin
receptor genes (SSTR1). No LOH was detected at any of the informative loci
tested for on ch4 or ch11.
相似文献