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1.
Y.R. Song B. Wu Y.T. Yang J. Chen L.J. Zhang Z.W. Zhang H.Y. Shi C.L. Huang J.X. Pan P. Xie 《Brazilian journal of medical and biological research》2015,48(11):973-982
Bipolar disorder (BD) is a common psychiatric mood disorder affecting more than 1-2%
of the general population of different European countries. Unfortunately, there is no
objective laboratory-based test to aid BD diagnosis or monitor its progression, and
little is known about the molecular basis of BD. Here, we performed a comparative
proteomic study to identify differentially expressed plasma proteins in various BD
mood states (depressed BD, manic BD, and euthymic BD) relative to healthy controls. A
total of 10 euthymic BD, 20 depressed BD, 15 manic BD, and 20 demographically matched
healthy control subjects were recruited. Seven high-abundance proteins were
immunodepleted in plasma samples from the 4 experimental groups, which were then
subjected to proteome-wide expression profiling by two-dimensional electrophoresis
and matrix-assisted laser desorption/ionization-time-of-flight/time-of-flight tandem
mass spectrometry. Proteomic results were validated by immunoblotting and
bioinformatically analyzed using MetaCore. From a total of 32 proteins identified
with 1.5-fold changes in expression compared with healthy controls, 16 proteins were
perturbed in BD independent of mood state, while 16 proteins were specifically
associated with particular BD mood states. Two mood-independent differential
proteins, apolipoprotein (Apo) A1 and Apo L1, suggest that BD pathophysiology may be
associated with early perturbations in lipid metabolism. Moreover, down-regulation of
one mood-dependent protein, carbonic anhydrase 1 (CA-1), suggests it may be involved
in the pathophysiology of depressive episodes in BD. Thus, BD pathophysiology may be
associated with early perturbations in lipid metabolism that are independent of mood
state, while CA-1 may be involved in the pathophysiology of depressive episodes. 相似文献
2.
In this study, the carbonic anhydrase (CA) enzyme was purified from Black Sea trout (Salmo trutta Labrax Coruhensis) kidney with a specific activity of 603.77 EU/mg and a yield of 35.5% using Sepharose-4B-l-tyrosine- sulphanilamide affinity column chromatography. For determining the enzyme purity and subunit molecular mass, sodiumdodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) was performed and single band was observed. The molecular mass of subunit was found approximately 29.71 kDa. The optimum temperature, activation energy (Ea), activation enthalpy (ΔH) and Q10 values were obtained from Arrhenius plot. Km and Vmax values for p-nitrophenyl acetate of the purified enzyme were calculated from Lineweaver-Burk graphs. In addition, the inhibitory effects of different heavy metal ions (Fe2+, Pb2+, Co2+, Ag+ and Cu2+) on Black Sea trout kidney tissue CA enzyme activities were investigated by using esterase method under in vitro conditions. The heavy metal concentrations inhibiting 50% of enzyme activity (IC50) were obtained. Finally Ki values and inhibition types were calculated from Lineweaver-Burk graphs. 相似文献
3.
目的:探讨Masimo SET(R)Rad-57碳氧血氧测量仪在急性一氧化碳中毒患者早期诊断中的价值。方法:将2013年11月-2014年4月收治的急性一氧化碳中毒患者35例按照临床症状和体征分为轻、中、重度一氧化碳中毒,并与Masimo SET(R)Rad-57碳氧血氧测量仪测得的碳氧血红蛋白饱和度进行比较。结果:Masimo SET(R)Rad-57碳氧血氧测量仪测得的碳氧血红蛋白饱和度与一氧化碳中毒的病情相符,且轻、中、重度组间均有显著性差异(P均0.01)。结论:急诊科应用Masimo SET(R)Rad-57碳氧血氧测量仪对一氧化碳中毒患者有早期诊断价值。 相似文献
4.
β-碳酸酐酶(β-carbonic anhydrases,β-CAs)是一种锌金属酶,能高效催化CO2的水合作用,参与包括呼吸、p H及CO2稳态、生物合成、毒力调节等生理过程,在生命活动中起重要作用。β-CAs广泛分布于真菌、细菌、绿藻、植物及少数原生动物和后生动物中,但在脊椎动物体内未发现。因此将β-CAs作为靶点,设计开发抗细菌、真菌、寄生虫感染药物有着广阔的前景。本文就β-CAs的分布、生理功能、抑制剂及其作为抗寄生虫药物靶点的研究进展作一综述。 相似文献
5.
Genetic ablation of carbonic anhydrase IX disrupts gastric barrier function via claudin‐18 downregulation and acid backflux 下载免费PDF全文
A. K. Singh K. A. Mäkelä A. Seidler Y. Liu G. Gros H. Bartels K. H. Herzig U. Seidler 《Acta physiologica (Oxford, England)》2018,222(4)
Aim
This study aimed to explore the molecular mechanisms for the parietal cell loss and fundic hyperplasia observed in gastric mucosa of mice lacking the carbonic anhydrase 9 (CAIX).Methods
We assessed the ability of CAIX‐knockout and WT gastric surface epithelial cells to withstand a luminal acid load by measuring the pHi of exteriorized gastric mucosa in vivo using two‐photon confocal laser scanning microscopy. Cytokines and claudin‐18A2 expression was analysed by RT‐PCR.Results
CAIX‐knockout gastric surface epithelial cells showed significantly faster pHi decline after luminal acid load compared to WT. Increased gastric mucosal IL‐1β and iNOS, but decreased claudin‐18A2 expression (which confer acid resistance) was observed shortly after weaning, prior to the loss of parietal and chief cells. At birth, neither inflammatory cytokines nor claudin‐18 expression were altered between CAIX and WT gastric mucosa. The gradual loss of acid secretory capacity was paralleled by an increase in serum gastrin, IL‐11 and foveolar hyperplasia. Mild chronic proton pump inhibition from the time of weaning did not prevent the claudin‐18 decrease nor the increase in inflammatory markers at 1 month of age, except for IL‐1β. However, the treatment reduced the parietal cell loss in CAIX‐KO mice in the subsequent months.Conclusions
We propose that CAIX converts protons that either backflux or are extruded from the cells rapidly to CO2 and H2O, contributing to tight junction protection and gastric epithelial pHi regulation. Lack of CAIX results in persistent acid backflux via claudin‐18 downregulation, causing loss of parietal cells, hypergastrinaemia and foveolar hyperplasia. 相似文献6.
High effective cytosolic H+ buffering in mouse cortical astrocytes attributable to fast bicarbonate transport 下载免费PDF全文
Cytosolic H+ buffering plays a major role for shaping intracellular H+ shifts and hence for the availability of H+ for biochemical reactions and acid/base‐coupled transport processes. H+ buffering is one of the prime means to protect the cell from large acid/base shifts. We have used the H+ indicator dye BCECF and confocal microscopy to monitor the cytosolic H+ concentration, [H+]i, in cultured cortical astrocytes of wild‐type mice and of mice deficient in sodium/bicarbonate cotransporter NBCe1 (NBCe1‐KO) or in carbonic anhydrase isoform II (CAII‐KO). The steady‐state buffer strength was calculated from the amplitude of [H+]i transients as evoked by CO2/HCO3? and by butyric acid in the presence and absence of CO2/HCO3?. We tested the hypotheses if, in addition to instantaneous physicochemical H+ buffering, rapid acid/base transport across the cell membrane contributes to the total, “effective” cytosolic H+ buffering. In the presence of 5% CO2/26 mM HCO3?, H+ buffer strength in astrocytes was increased 4–6 fold, as compared with that in non‐bicarbonate, HEPES‐buffered solution, which was largely attributable to fast HCO3? transport into the cells via NBCe1, supported by CAII activity. Our results show that within the time frame of determining physiological H+ buffering in cells, fast transport and equilibration of CO2/H+/HCO3? can make a major contribution to the total “effective” H+ buffer strength. Thus, “effective” cellular H+ buffering is, to a large extent, attributable to membrane transport of base equivalents rather than a purely passive physicochemical process, and can be much larger than reported so far. Not only physicochemical H+ buffering, but also rapid import of HCO3? via the electrogenic sodium‐bicarbonate cotransporter NBCe1, supported by carbonic anhydrase II (CA II), was identified to enhance cytosolic H+ buffer strength substantially. GLIA 2015;63:1581–1594 相似文献
7.
8.
《Journal of gastrointestinal cancer》1996,19(1):31-38
Summary
Conclusion
We established a new human pancreatic adenocarcinoma cell line, MDAPanc-28. Studies on this new line indicate that it expresses
both acinar and ductal gene products suggesting that the patterns of gene expression in the pancreatic adenocarcinoma from
which this cell line arose have features similar to those of the protodifferentiated cells hypothesized by Rutter and his
colleagues for the developing pancreas (1,2).
Background The cell line arose from a tumor that, like most pancreatic adenocarcinomas, was ductal on the basis of its histological appearance.
Methods Once the cell line was established in culture, they were subjected to cytogenetic analysis and tested for their ability to
grow in nude mice. RNA from the cells was analyzed by Northern blot analysis and PCR of reverse transcribed cDNA for the expression
of both acinar and duct cell gene products. DNA was analyzed for the presence of mutated K-ras at codon 12.
Results The cell line expressed trypsin and ribonuclease RNA, which are considered to be acinar cell markers, and carbonic anhydrase
II (CAII), which is considered to be a duct-cell markers. The histological appearance of xenografts in nude mice was similar
to that of the tumor from which the cell line was established. The chromosome number varied between 46 and 60. 相似文献
9.
Ioanna Ledaki Alan McIntyre Simon Wigfield Francesca Buffa Simon McGowan Dilair Baban Ji-liang Li Adrian L. Harris 《Oncotarget》2015,6(23):19413-19427
Carbonic anhydrase IX (CAIX) is strongly induced by hypoxia and its overexpression is associated with poor therapeutic outcome in cancer. Here, we report that hypoxia promotes tumour heterogeneity through the epigenetic regulation of CAIX. Based on hypoxic CAIX expression we identify and characterize two distinct populations of tumour cells, one that has inducible expression of CAIX and one that does not. The CAIX+ve population is enriched with cells expressing cancer stem cell markers and which have high self-renewal capacity. We show that differential CAIX expression is due to differences in chromatin structure. To further investigate the relationship between chromatin organization and hypoxic induction of CAIX expression we investigated the effect of JQ1 an inhibitor of BET bromodomain proteins and A366 a selective inhibitor of the H3K9 methyltransferase G9a/GLP. We identified that these drugs were able to modulate hypoxic CAIX expression induction. This further highlights the role of epigenetic modification in adaption to hypoxia and also in regulation of heterogeneity of cells within tumours. Interestingly, we identified that the two subpopulations show a differential sensitivity to HDAC inhibitors, NaBu or SAHA, with the CAIX positive showing greater sensitivity to treatment. We propose that drugs modulating chromatin regulation of expression may be used to reduce heterogeneity induced by hypoxia and could in combination have significant clinical consequences. 相似文献
10.
目的探讨碳酸酐酶IX(carbonic anhydrase-IX,CA-IX)在宫颈脱落细胞中的表达情况及与高危型人乳头瘤病毒(high risk-human papilloma virus,HR-HPV)感染的关系,分析CA-IX预测宫颈病变自然转归方向的价值。方法运用免疫细胞化学技术观察CA-IX在不同宫颈病变宫颈脱落细胞中的表达,采用HC-Ⅱ测定HR-HPV DNA,定期随访,比较CA-IX表达与HR-HPV感染状态的相关性。结果 CA-IX的表达与HPV的感染存在相关性(χ2=81.8,P=0.000)。低级别〔宫颈炎、宫颈上皮内瘤变(cervical intraepithelial neoplasia,CIN-Ⅰ)〕和高级别(CIN-Ⅱ、CIN-Ⅲ及宫颈癌)宫颈病变,CA-IX的阳性表达率差异有统计学意义(χ2=4.5,P=0.032)。不同HPV感染状态下(持续性感染、一过性感染、无HPV感染),CA-IX表达的阳性率分别为60.6%、38.4%、15.6%,差异具有统计学意义(χ2=11.69,P=0.001)。结论 CA-IX的表达与HPV感染相关,在持续性HPV感染中,CA-IX的表达阳性率较一过性HPV感染、无HPV感染明显升高,提示CA-IX有可能是参与持续HPV感染致宫颈上皮内瘤变的分子标志之一。 相似文献