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151.
运用敏感的B_9细胞增殖试验检测了81例多发性骨髓瘤(MM)患者血清IL-6活性,同时分析了标本的几种急性相蛋白含量,结果表明,68%MM患者血清中IL-6活性大于5μ/ml(正常对照为5μ/ml以下),几种急性相蛋白中C-反应性蛋白(CRP)在MM时升高(P<0.01),平均达正常对照组的17倍以上,MM患者补体C_4与正常对照组无差异(p>0.05),C_3、白蛋白及转铁蛋白在MM时分别比正常下降24.42%、38.83%和32.80%,且与疾病分期有关,在血清IL-6大于5μ/ml的55例中,IL-6活性与CRP、C_3、白蛋白的相关系数分别为0.46,-0.34和-0.29,IL-6与转铁蛋白浓度相关不明显。本文结果提示:CRP、C_3及白蛋白等含量的变化可作为反映MM病情的简易而敏感的指标。 相似文献
152.
Antibodies specific for dsDNA appear to have different genetic origins and pathogenic consequences, compared with histone/dsDNA-specific antibodies, in a recently described murine model. The purpose of this study was to examine if this is also true in human lupus. Sera from 40 SLE families (comprising 40 probands and 153 first-degree relatives), and 45 normal adult controls were assayed for the levels of anti-dsDNA, anti-H1/dsDNA, anti-H2A/H2B/dsDNA, and anti-H3/H4/dsDNA autoantibodies by ELISA. Both the probands and the first-degree relatives exhibited significantly increased levels of antinuclear antibodies (ANA) targeting the different subnucleosomal epitopes. Importantly, probands with anti-dsDNA antibodies had a significantly higher incidence of renal disease compared with those with just anti-H2A/H2B/dsDNA antibodies, in resonance with murine studies. The frequency of anti-dsDNA and anti-H2A/H2B/DNA ANA among the first-degree relatives was 11.8% and 18.3%, respectively. Surprisingly, whereas probands with anti-dsDNA ANA had families with several seropositive members, first-degree relatives of patients with anti-H2A/H2B/DNA ANA (but not anti-dsDNA ANA) were uniformly ANA-free. These findings suggest that anti-dsDNA ANA in lupus may not only have worse disease associations, they may also have very different genetic origins, compared with anti-H2A/H2B/DNA (or anti-nucleosome) ANA. 相似文献
153.
154.
Jin H Kang Y Xiao C Zhu K Ma Y Xie Q Ma J Xie Q He C Yang Z Sun Z Zhang X Chen M Zhang F Wang B 《Viral immunology》2005,18(3):539-548
Prime-boost strategy has been exhibited its potency to enhance immune responses, which would be important to the success to develop a vaccine against the foot-and-mouth disease virus (FMDV). An eukaryotic expression construct encoding the FMDV capsid VP1 protein with a recombinant VP1 protein or a commercial FMDV vaccine were tested in the prime-boost strategy in mice and cattle trials. The levels of induced specific antibodies, T cell proliferations, and DTH activities were significantly higher in the prime-boost groups than in those vaccinated with DNA, protein or FMDV vaccine alone. More importantly, the levels of neutralizing antibodies in the former groups were significantly higher than others and could last for at least four months in cattle trials. This study suggests that the prime-boost strategy significantly improves the effective immunity and may provide a longer protection against FMDV infection. 相似文献
155.
156.
Chen YN Chen SY Zeng LJ Ran JM Xie B Wu MY Wu YZ 《British journal of biomedical science》2003,60(1):9-13
Sulphonylurea (SU) stimulates insulin secretion by pancreatic beta-cells and is generally used as a first-line treatment for type 2 diabetes. However, after long-term SU treatment (six months or over), some patients begin to show an increase in blood glucose once again (secondary SU failure). Two theories have been put forward to explain this failure--dysfunction of the proinsulin conversion machinery or insulin resistance. However, the primary pathogenesis behind secondary SU failure still needs to be investigated. Using a reliable technique that specifically identifies intact proinsulin (IPI), total proinsulin (TPI) and specific insulin (SI), this study aims to discover if a defect in the proinsulin converting mechanism plays a role in SU failure. Three groups were recruited for this study: healthy controls (n=8), SU responders (n=38) and secondary SU failures (n= 46). Serum concentrations of insulin-related molecules released in response to a standard glucose challenge test were compared between the groups. It was found that total SI was lower in the patient groups (P<0.05 compared to the control group), while TPI and IPI showed no distinct difference between the three groups (P>0.05). TPI:SI ratio and IPI:SI ratio showed marked increases in the patient groups (P<0.05 compared to control group), with no obvious quantitative difference between SU responders and secondary SU failures (P>0.05). Similar results for the Homa Insulin Resistant Index were found between the two patient groups. Interestingly, blood glucose at 180 mins after glucose challenge was significantly higher in the secondary SU failure group (P<0.05), with no correlation to SI, while the SU responder group showed good correlation between the parameters (P<0.05). We conclude that type 2 diabetes is associated with obvious dysfunction in the proinsulin-converting process and shows severe SI deficiency in responding to glucose challenge. Dysfunction of the proinsulin conversion mechanism was not an extra cause responsible for SU failure. 相似文献
157.
微波辐射免疫比浊法加速测定免疫球蛋白 总被引:1,自引:0,他引:1
本文应用微波辐射免疫比浊法加速测定免疫球蛋白(IgG、IgA、IgM).结果表明:用本法测定的线性范围较宽:IgG从3.24~51.92/L;IgA从0.49~7.92g/L;IgM从0.36~5.75/L.批内、批间精密度(CV):IgG从44~7.4%;IgA从4.1~9.5%;IgM从4.0~8.8%.本法与传统免疫比浊法和进口试剂自动免疫比浊法(Monarch 2000)测定比较,其结果相关良好,r从0.950至0.996,P>0.05.本法的特点是操作简便、快速,可明显缩短抗原和抗体反应达到终点的时间. 相似文献
158.
Induction of human airway smooth muscle apoptosis by neutrophils and neutrophil elastase 总被引:2,自引:0,他引:2
Oltmanns U Sukkar MB Xie S John M Chung KF 《American journal of respiratory cell and molecular biology》2005,32(4):334-341
Neutrophils are an important component of airway inflammation and may interact with human airway smooth muscle cells (HASMC). We investigated the effect of neutrophils and of neutrophil-derived proteases on HASMC survival. When co-incubated with neutrophils (0.1-1 x 10(6) cells/ml), attachment of human ASMC was reduced to 12.3 +/- 4.3% compared with untreated controls after 72 h. HASMC showed nuclear condensation and fragmentation (41.6 +/- 8.1% compared with baseline of 3.1 +/- 0.4%), and the biochemical markers of apoptosis, annexin V binding (9.7 +/- 0.7%; baseline 1.1 +/- 0.3%) and cleaved caspase-3 expression, were observed. The proteolytic activity released by neutrophils was essential for the proapoptotic effect because inhibition of elastase activity by alpha(1)-antitrypsin and MeOSuc-Ala-Ala-Pro-Ala-CMK (MSACK) reduced HASMC apoptosis. Human neutrophil elastase (0.1-3 microg/ml) induced apoptosis of HASMC, as well as other neutrophil serine proteases, cathepsin G, and proteinase 3. Fibronectin degradation products were present in HASMC supernatants exposed to neutrophil-conditioned media and to neutrophil elastase. The local release of proteases from neutrophils present in airway smooth muscle cells may lead to HASMC apoptosis as a result of matrix degradation and loss of cell attachment. This may limit pathologic changes such as ASMC hyperplasia and extracellular matrix deposition seen in airway remodeling. 相似文献
159.
Mark A Lovell J David Robertson Bruce A Buchholz Chengsong Xie William R Markesbery 《Neurobiology of aging》2002,23(2):179-186
The time course of formation of neurofibrillary tangles (NFT) and senile plaques (SP) in Alzheimer's disease (AD) brain is unknown. Above ground nuclear weapons testing in the late 1950s and early 1960s led to significantly increased levels of 14C in the atmosphere and carbon cycle. Because the amyloid beta peptide of SP and paired helical filaments of NFT, once formed, are relatively resistant to degradation, 14C levels observed in SP and NFT should reflect their year of formation. The purpose of this study was to develop a method to determine whether 14C levels could be used to define NFT and SP ages. Using accelerator mass spectrometry to measure bomb-pulse 14C levels, we determined the average age of formation of isolated SP and NFT fractions in bulk brain samples of 6 AD subjects. Although preliminary, the results demonstrate that it is possible to use bomb pulse 14C to determine the average year of formation of NFT and SP in the brain in AD. In addition, the data show that these structures, once formed, have a much slower carbon turnover rate than normal brain and are not in a formation/enzymatic degradation equilibrium. 相似文献
160.
YiFeng Li ChunHong Shao Dandan Zhang Min Zhao Ling Lin Pengrong Yan Yuying Xie Kaida Jiang Li Jin 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2006,(3):269-273
Heroin dependence is resulted from the interaction between multiple genetic and environmental factors. Subjective craving is considered to be a central phenomenon, which contributes to the continuation of drug use in active abuser and the occurrence of relapse in detoxified abusers. Dopamine pathway has been implicated in the cue-elicited craving for a variety of addictive substances. The objective of this study was to test the hypothesis that heroin addicts carrying specific variants in dopamine-related genes would have higher levels of craving following exposure to a heroin-related cue. Craving induced by a series of exposure to heroin-related cue was assessed in a cohort of Chinese heroin abuser (n = 420) recruited from natural abstinence center at Shanghai. Significantly stronger cue-elicited heroin craving was found in individuals carrying D2 dopamine receptor gene (DRD2) TaqI RFLP A1 allele than the non-carriers (P < 0.001). Furthermore, we did not observed significant association of cue-elicited craving with the nine-repeat allelic variants in dopamine transporter gene (DAT) SLC6A3 and with the dinucleotide repeat polymorphism (DRP) 148bp allele in D5 dopamine receptor gene (DRD5). The results of our study suggest that human dopamine pathway be involved in cue-induced heroin craving, and indicate a potential genetic risk factor for persistent heroin behavior and relapse. 相似文献