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排序方式: 共有371条查询结果,搜索用时 15 毫秒
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Tuberculosis (TB) remains one of the most devastating infectious diseases and its eradication is still unattainable given the limitations of current technologies for diagnosis, treatment and prevention. The World Health Organization's goal to eliminate TB globally by 2050 remains an ongoing challenge as delayed diagnosis and misdiagnosis of TB continue to fuel the worldwide epidemic. Despite considerable improvements in diagnostics for the last few decades, a simple and effective point-of-care TB diagnostic test is yet not available. Here, we review the current assays used for TB diagnosis, and highlight the recent advances in nanotechnology and microfluidics that potentially enable new approaches for TB diagnosis in resource-constrained settings. 相似文献
3.
As computational capabilities increase, molecular dynamics (MD) simulations become important tools of simulating reality. These simulations are especially useful for compressible gas mixture problems. In this study, binary diffusion of helium and argon was examined using a hard-sphere MD simulation method. For the sake of computational speed, low spacing ratios were chosen. Binary mass diffusion of gases in two equally sized halves of a box was simulated for identical initial kinetic energies and number densities. It has been noted that a purely mass diffusion mechanism of different gases is not physically possible. The resultant gas mixtures of several diffusion simulations were used as initial conditions for combined heat transfer – Couette flow, and heating and cooling experiments. The results showed the interesting behaviour of the mixture, which was subjected to various wall conditions. Energy of heavier molecules is found to be more sensitive to the wall velocities and less sensitive to the wall temperatures than lighter molecules. Diffusion, heat transfer, viscosity and heat capacity coefficients are deduced as well. 相似文献
4.
Matthias Hardtke-Wolenski Lilli Kraus Christel Schmetz Britta Trautewig Fatih Noyan Florian W. R. Vondran Hueseyin Bektas Juergen Klempnauer Elmar Jaeckel Thorsten Lieke 《PloS one》2013,8(10)
Background
T cells are known to participate in the response to tumor cells and react with cytotoxicity and cytokine release. At the same time tumors established versatile mechanisms for silencing the immune responses. The interplay is far from being completely understood. In this study we show contacts between tumor cells and lymphocytes revealing novel characteristics in the interaction of T cells and cancer cells in a way not previously described.Methods/ Findings
Experiments are based on the usage of a hydrophilic fluorescent dye that occurs free in the cytosol and thus transfer of fluorescent cytosol from one cell to the other can be observed using flow cytometry. Tumor cells from cell lines of different origin or primary hepatocellular carcinoma (HCC) cells were incubated with lymphocytes from human and mice. This exposure provoked a contact dependent uptake of tumor derived cytosol by lymphocytes – even in CD4+ T cells and murine B cells – which could not be detected after incubation of lymphocytes with healthy cells. The interaction was a direct one, not requiring the presence of accessory cells, but independent of cytotoxicity and TCR engagement.Electron microscopy disclosed 100-200nm large gaps in the cell membranes of connected cells which separated viable and revealed astonishing outcome. While the lymphocytes were induced to proliferate in a long term fashion, the tumor cells underwent a temporary break in cell division. The in vitro results were confirmed in vivo using a murine acute lymphoblastic leukemia (ALL) model. The arrest of tumor proliferation resulted in a significant prolonged survival of challenged mice.Conclusions
The reported cell-cell contacts reveal new characteristics i.e. the enabling of cytosol flow between the cells including biological active proteins that influence the cell cycle and biological behaviour of the recipient cells. This adds a completely new aspect in tumor induced immunology. 相似文献5.
6.
Fatih Oltulu Duygu Ç. Kocatürk Yasemin Adalı Berrin Özdil Eda Açikgöz Çevik Gürel N. Ulku Karabay Yavasoğlu Huseyin Aktuğ 《Journal of cellular biochemistry》2019,120(10):18066-18076
Embryonic developmental stages and regulations have always been one of the most intriguing aspects of science. Since the cancer stem cell discovery, striking for cancer development and recurrence, embryonic stem cells and control mechanisms, as well as cancer cells and cancer stem cell control mechanisms become important research materials. It is necessary to reveal the similarities and differences between somatic and cancer cells which are formed of embryonic stem cells divisions and determinations. For this purpose, mouse embryonic stem cells (mESCs), mouse skin fibroblast cells (MSFs) and mouse lung squamous cancer cells (SqLCCs) were grown in vitro and the differences between these three cell lines signalling regulations of mechanistic target of rapamycin (mTOR) and autophagic pathways were demonstrated by immunofluorescence and real-time polymerase chain reaction. Expressional differences were clearly shown between embryonic, cancer and somatic cells that mESCs displayed higher expressional level of Atg10, Hdac1 and Cln3 which are related with autophagic regulation and Hsp4, Prkca, Rhoa and ribosomal S6 genes related with mTOR activity. LC3 and mTOR protein levels were lower in mESCs than MSFs. Thus, the mechanisms of embryonic stem cell regulation results in the formation of somatic tissues whereas that these cells may be the causative agents of cancer in any deterioration. 相似文献
7.
Kuşçu Gökçe Ceren Gürel Çevik Buhur Aylin Oltulu Fatih Akman Levent Köse Timur Yavaşoğlu Nefise Ülkü Karabay Yavaşoğlu Altuğ 《Molecular biology reports》2022,49(3):1721-1729
Molecular Biology Reports - Polycystic ovary syndrome (PCOS) is a metabolic disease that causes infertility due to anovulation in women in reproductive age. It is known that clomiphene citrate (CC)... 相似文献
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G?k?e Güllü Irem Peker Aptullah Haholu Fatih Eren Zafer Kü?ükodaci Bülent Güle? Hüseyin Baloglu Can Erzik Ayse ?zer Mustafa Akkiprik 《Genetics and molecular biology》2015,38(1):21-29
The functional role of IGFBP5 in breast cancer is complicated. Experimental and
bioinformatics studies have shown that IGFBP5 is targeted by miR-140-5p and miR-193b,
although this has not yet been proven in clinical samples. The aim of this study was
to evaluate the expression of miR-140-5p and miR-193b in breast cancer and adjacent
normal tissue and assess its correlation with IGFBP5 and the clinicopathological
characteristics of the tumors. IGFBP5 protein expression was analyzed
immunohistochemically and IGFBP5, miR-140 and miR-193b mRNA expression levels were
analyzed with real-time RT-PCR. Tumor tissue had higher miR-140-5p expression than
adjacent normal tissue (p = 0.015). Samples with no immunohistochemical staining for
IGFBP5 showed increased miR-140-5p expression (p = 0.009). miR-140-5p expression was
elevated in invasive ductal carcinomas (p = 0.002), whereas basal-like tumors had
decreased expression of miR-140-5p compared to other tumors (p = 0.008). Lymph
node-positive samples showed an approximately 13-fold increase in miR-140-5p
expression compared to lymph node-negative tissue (p = 0.049). These findings suggest
that miR-140-5p, but not miR-193b, could be an important determinant of IGFBP5
expression and clinical phenotype in breast cancer patients. Further studies are
needed to clarify the expressional regulation of IGFBP5 by miR-140-5p. 相似文献
10.
Fatih Arslan Joo Y. Hong Vydehi Kanneganti Sei-Kyoung Park Susan W. Liebman 《PLoS genetics》2015,11(1)
Prions are self-perpetuating conformational variants of particular proteins. In yeast, prions cause heritable phenotypic traits. Most known yeast prions contain a glutamine (Q)/asparagine (N)-rich region in their prion domains. [PSI+], the prion form of Sup35, appears de novo at dramatically enhanced rates following transient overproduction of Sup35 in the presence of [PIN+], the prion form of Rnq1. Here, we establish the temporal de novo appearance of Sup35 aggregates during such overexpression in relation to other cellular proteins. Fluorescently-labeled Sup35 initially forms one or a few dots when overexpressed in [PIN+] cells. One of the dots is perivacuolar, colocalizes with the aggregated Rnq1 dot and grows into peripheral rings/lines, some of which also colocalize with Rnq1. Sup35 dots that are not near the vacuole do not always colocalize with Rnq1 and disappear by the time rings start to grow. Bimolecular fluorescence complementation failed to detect any interaction between Sup35-VN and Rnq1-VC in [PSI
+][PIN
+] cells. In contrast, all Sup35 aggregates, whether newly induced or in established [PSI
+], completely colocalize with the molecular chaperones Hsp104, Sis1, Ssa1 and eukaryotic release factor Sup45. In the absence of [PIN+], overexpressed aggregating proteins such as the Q/N-rich Pin4C or the non-Q/N-rich Mod5 can also promote the de novo appearance of [PSI
+]. Similar to Rnq1, overexpressed Pin4C transiently colocalizes with newly appearing Sup35 aggregates. However, no interaction was detected between Mod5 and Sup35 during [PSI+] induction in the absence of [PIN
+]. While the colocalization of Sup35 and aggregates of Rnq1 or Pin4C are consistent with the model that the heterologous aggregates cross-seed the de novo appearance of [PSI
+], the lack of interaction between Mod5 and Sup35 leaves open the possibility of other mechanisms. We also show that Hsp104 is required in the de novo appearance of [PSI+] aggregates in a [PIN
+]-independent pathway. 相似文献