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11.
J. Braham Ida Sarova-Pinhas M. Crispin R. Golan N. Levin A. Szeinberg 《BMJ (Clinical research ed.)》1969,2(5656):552-555
Reduction of dopamine concentrations in the brains of patients with Parkinsonism, together with reported clinical improvement after the administration of dihydroxyphenylalanine, has led to the hypothesis that impaired hydroxylation of tyrosine may be associated with the disease. To test this hypothesis oral loading tests with L-phenylalanine and tyrosine were carried out in patients and controls. After phenylalanine lower blood levels of this were found in Parkinsonian patients than in controls, but tyrosine levels were the same. After tyrosine lower levels of this were also found in patients compared with controls. It is suggested that these findings indicate a decreased rate of tyrosine utilization in Parkinson''s disease together with intestinal malabsorption; the latter is supported by the finding of abnormal D-xylose tolerance in these patients. 相似文献
12.
Baleen whales: preliminary evidence for forestomach microbial fermentation. 总被引:2,自引:1,他引:1
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Baleen whales have a multichambered stomach divided into three distinct compartments. The forestomach (first compartment) consists of noncornified and nonglandular tissue and appears to be analogous to the tissue of the rumen. The exact function of the forestomach is unknown; however, we have detected volatile fatty acids in forestomach samples from seven bowhead (Balaena mysticetus) and four gray (Escherichtius robustus) whales. Acetic, propionic, and butyric acids were found in all samples. Seven whale samples also contained valeric, isobutyric, isovaleric, and isocaproic acids. Bacterial counts in 10 of the samples ranged from 5 X 10(8) to 630 X 10(8)/ml of fluid. The types, concentrations, and relative proportions of volatile fatty acids, the presence of significant levels of bacteria, and the morphology of the digestive tract support the hypothesis that a microbial forestomach fermentation occurs in these two species of baleen whales. 相似文献
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14.
Molecular Determinants of AHPN (CD437)-Induced Growth Arrest and Apoptosis in Human Lung Cancer Cell Lines 总被引:12,自引:0,他引:12
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Yin Li Bingzhen Lin Anissa Agadir Ru Liu Marcia I. Dawson John C. Reed Joseph A. Fontana Frdric Bost Peter D. Hobbs Yun Zheng Guo-quan Chen Braham Shroot Dan Mercola Xiao-kun Zhang 《Molecular and cellular biology》1998,18(8):4719-4731
6-[3-(1-Adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (AHPN or CD437), originally identified as a retinoic acid receptor γ-selective retinoid, was previously shown to induce growth inhibition and apoptosis in human breast cancer cells. In this study, we investigated the role of AHPN/CD437 and its mechanism of action in human lung cancer cell lines. Our results demonstrated that AHPN/CD437 effectively inhibited lung cancer cell growth by inducing G0/G1 arrest and apoptosis, a process that is accompanied by rapid induction of c-Jun, nur77, and p21WAF1/CIP1. In addition, we found that expression of p53 and Bcl-2 was differentially regulated by AHPN/CD437 in different lung cancer cell lines and may play a role in regulating AHPN/CD437-induced apoptotic process. On constitutive expression of the c-JunAla(63,73) protein, a dominant-negative inhibitor of c-Jun, in A549 cells, nur77 expression and apoptosis induction by AHPN/CD437 were impaired, whereas p21WAF1/CIP1 induction and G0/G1 arrest were not affected. Furthermore, overexpression of antisense nur77 RNA in A549 and H460 lung cancer cell lines largely inhibited AHPN/CD437-induced apoptosis. Thus, expression of c-Jun and nur77 plays a critical role in AHPN/CD437-induced apoptosis. Together, our results reveal a novel pathway for retinoid-induced apoptosis and suggest that AHPN/CD437 or analogs may have a better therapeutic efficacy against lung cancer. 相似文献
15.
Permeability of the cercarial tail in Proterometra macrostoma was examined in vitro with 1 mM 3H-glucose, which tails absorb by diffusion alone. Naturally emerged cercariae (bodies withdrawn into tails) were permeable, but they rapidly (3 min) equilibrated with glucose in the bathing medium and maintained steady state for 4 hr. Metabolism of absorbed glucose was not detectable until after 90 min, and radioactivity in bodies dissected from tails after 4 hr was negligible. On the basis of cercarial water content (90% of total weight) and absorbed isotope at steady state, the calculated volume of the equilibrating compartment was 4% of an intact cercaria. This value correlated well with that of the tegument (3-5%), which was 1-2 microm thick as seen by transmission electron microscopy. A continuous, electron-dense basal membrane/lamina separated the tegument from subtegument. We conclude that the glycocalyx and external plasma membrane are freely permeable, whereas the basal membrane is the barrier that effectively isolated the subtegument from exogenous glucose. The basal membrane also may be the primary structure that protects the subtegument and cercarial body from effects of osmotic stress. 相似文献
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17.
J Braham 《BMJ (Clinical research ed.)》1971,4(5781):212-213
18.
Sabrina Ait Braham Fouzia Hussain Roberto Morellon-Sterling Shagufta Kamal Jakub F. Kornecki Oveimar Barbosa Djamel Edine Kati Roberto Fernandez-Lafuente 《Biotechnology progress》2019,35(2):e2768
Alcalase was scarcely immobilized on monoaminoethyl-N-aminoethyl (MANAE)-agarose beads at different pH values (<20% at pH 7). The enzyme did not immobilize on MANAE-agarose activated with glutaraldehyde at high ionic strength, suggesting a low reactivity of the enzyme with the support functionalized in this manner. However, the immobilization is relatively rapid when using low ionic strength and glutaraldehyde activated support. Using these conditions, the enzyme was immobilized at pH 5, 7, and 9, and in all cases, the activity vs. Boc-Ala-ONp decreased to around 50%. However, the activity vs. casein greatly depends on the immobilization pH, while at pH 5 it is also 50%, at pH 7 it is around 200%, and at pH 9 it is around 140%. All immobilized enzymes were significantly stabilized compared to the free enzyme when inactivated at pH 5, 7, or 9. The highest stability was always observed when the enzyme was immobilized at pH 9, and the worst stability occurred when the enzyme was immobilized at pH 5, in agreement with the reactivity of the amino groups of the enzyme. Stabilization was lower for the three preparations when the inactivation was performed at pH 5. Thus, this is a practical example on how the cooperative effect of ion exchange and covalent immobilization may be used to immobilize an enzyme when only one independent cause of immobilization is unable to immobilize the enzyme, while adjusting the immobilization pH leads to very different properties of the final immobilized enzyme preparation. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2768, 2019. 相似文献
19.
Braham Parkash Atul Ranjan Vinod Tiwari Sharad Kumar Gupta Navrinder Kaur Vibha Tandon 《PloS one》2012,7(11)
Background
The genome of retroviruses, including HIV-1, is packaged as two homologous (+) strand RNA molecules, noncovalently associated close to their 5′-end in a region called dimer linkage structure (DLS). Retroviral HIV-1 genomic RNAs dimerize through complex interactions between dimerization initiation sites (DIS) within the (5′-UTR). Dimer formation is prevented by so calledLong Distance Interaction (LDI) conformation, whereas Branched Multiple Hairpin (BMH) conformation leads to spontaneous dimerization.Methods and Results
We evaluated the role of SL1 (DIS), PolyA Hairpin signal and a long distance U5-AUG interaction by in-vitro dimerization, conformer assay and coupled dimerization and template-switching assays using antisense PNAs. Our data suggests evidence that PNAs targeted against SL1 produced severe inhibitory effect on dimerization and template-switching processes while PNAs targeted against U5 region do not show significant effect on dimerization and template switching, while PNAs targeted against AUG region showed strong inhibition of dimerization and template switching processes.Conclusions
Our results demonstrate that PNA can be used successfully as an antisense to inhibit dimerization and template switching process in HIV -1 and both of the processes are closely linked to each other. Different PNA oligomers have ability of switching between two thermodynamically stable forms. PNA targeted against DIS and SL1 switch, LDI conformer to more dimerization friendly BMH form. PNAs targeted against PolyA haipin configuration did not show a significant change in dimerization and template switching process. The PNA oligomer directed against the AUG strand of U5-AUG duplex structure also showed a significant reduction in RNA dimerization as well as template- switching efficiency.The antisense PNA oligomers can be used to regulate the shift in the LDI/BMH equilibrium. 相似文献20.
Besma Lakhal Sonia Ben-Hadj-Khalifa Nouha Bouali Pascal Philipert Françoise Audran Rim Braham Elghezal Hatem Charles Sultan Ali Saad 《Gene》2012