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91.
The progressive liquid-phase layer-by-layer (LbL) growth of anisotropic multicomponent layer-based porous coordination polymers (PCPs) of the general formula [M(L)(P)(0.5)] (M: Cu(2+), Zn(2+); L: dicarboxylate linker; P: dinitrogen pillar ligand) was investigated by using either pyridyl- or carboxyl-terminated self-assembled monolayers (SAMs) on gold substrates as templates. It was found that the deposition of smooth, highly crystalline, and oriented multilayer films of these PCPs depends on the conditions at the early growth cycles. In the case of a two-step process with an equimolar mixture of L and P, growth along the [001] direction is strongly preferred. However, employing a three-step scheme with full separation of all components allows deposition along the [100] direction on carboxyl-terminated SAMs. Interestingly, the growth of additional layers on top of previously grown oriented seeding layers proved to be insensitive to the particular growth scheme and full retention of the initial orientation, either along the [001] or [100] direction, was observed. This homo- and heteroepitaxial LbL growth allows full control over the orientation and the layer sequence, including introduction of functionalized linkers and pillars.  相似文献   
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Evidence has been obtained for the formation of acylaluminium dichlorides by transmetalation between Cp2Zr(Cl)(acyl) and AlCl3. They have been shown to be reactive toward electrophiles at both the carbon and the oxygen of the acyl group.  相似文献   
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The reaction of amines with [(RhClCod)2] (Cod = 1,5-cyclooctadiene) gives monomeric compounds [RhCl(Am)Cod](Am = amine). Elementary analyses as well as IR and NMR spectra are consistent with their structure.On treatment with carbon monoxide at atmospheric pressure these compounds give a series of complexes, [RhCl(Am)(CO)2], identified by elementary analyses and IR spectra.The thermolysis of [RhCl(Aam)(CO)2] with Aam = allyamine gives [{RhCl(Aam)COn}] not perfectly isolated. The reaction of [{RhCl(CO)2}2] with 2-vinylpyridine leads to the same kind of compound [{RhCl(Vpy)COm}] with Vpy = 2 -vinylpyridine. This latter complex is identified by elementary analysis. The IR spectra of these two complexes show that the olefinic double bond of amines β,γ-insaturated interacts with a rhodium atom. Their properties are discussed.  相似文献   
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We investigated the antidiarrhoeic effect of the aqueous extract of Annona crassiflora leaves (AEAC). The AEAC decreased the diarrhoeic stools and enteropooling induced by castor oil, without altering total faecal output; moreover, the distance travelled by charcoal meal in the intestine was increased. Twenty-eight compounds were identified by LC-DAD-MS in the AEAC, including flavonoids, alkaloids and proanthocyanidins. In addition, two oligomeric series of condensed tannins of up to nine flavan-3-ol units were characterised by MALDI-MS. These data suggest that the antidiarrhoeic effect of the AEAC is related to its ability to inhibit intestinal secretion and/or to increase intestinal absorption. Moreover, the prokinetic effect of AEAC, together with its inhibitory effect on enteropooling induced by castor oil, explains why this extract decreased diarrhoeic faeces without altering the total faecal output. All these effects are in agreement with the pharmacological activity reported in the literature for many of the secondary metabolites identified.  相似文献   
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Disease progression in Tuberculosis (TB) is dependent on host’s immune system. Phyllanthus niruri, a traditional herb, has long been used to boost immune system in Indonesian society. This study aimed to observe the potential role of P. niruri in inducing immune cells activity in TB patients by in vitro approach. Peripheral blood mononuclear cells (PBMCs) and macrophages were collected from active pulmonary TB patients. After stimulation with graded doses of P. niruri aqueous extract, cell proliferation, phagocytic activity and nitric oxide (NO) release were analysed. P. niruri aqueous extract induced proliferation of PBMCs, increased NO release, and improved macrophages phagocytic activity. These effects were observed in a dose-dependent manner. This may lead to further research for the potential role of P. niruri as immunomodulatory adjuvant therapy for TB patients.  相似文献   
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