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991.
992.
How do oncologists choose therapy for the elderly? Oncologists assigned patients aged 65 years or older with incurable non-small cell lung cancer to: (a) carboplatin (AUC = 2) + paclitaxel 50 mg/m(2) days 1, 8, 15 (28-day cycle × 4) followed by gefitinib; or (b) gefitinib 250?mg/day. With (a), 12 of 34 were progression-free at 6 months; median time to cancer progression was 3.9 months. With (b), the same occurred in 11 of 28 patients with the latter being 4.9 months. The most common reason for conventional chemotherapy was oncologists' opinion that the cancer was aggressive, and for gefitinib alone, patients' reluctance to receive chemotherapy. Interestingly, age had no influence.  相似文献   
993.
车彪 《中国厂矿医学》2011,24(7):635-636
髋关节骨性关节炎是一种慢性进行性骨关节病,也是骨科常见疾患,多见于老年人,发病率随年龄增大而增高;是以慢性进行性软骨变性和软骨下及关节周围新骨形成为主要特点的退行性疾病。随着人口老龄化,越来越多的人患有髋关节骨性关节炎。  相似文献   
994.
Recently, we have demonstrated the feasibility of using hemodynamic response imaging (HRI), a functional magnetic resonance imaging (MRI) method combined with hypercapnia and hyperoxia, for monitoring vascular changes during liver pathologies without the need of contrast material. In this study, we evaluated HRI ability to assess changes in liver tumor vasculature during tumor establishment, progression, and antiangiogenic therapy. Colorectal adenocarcinoma cells were injected intrasplenically to model colorectal liver metastasis (CRLM) and the Mdr2 knockout mice were used to model primary hepatic tumors. Hepatic perfusion parameters were evaluated using the HRI protocol and were compared with contrast-enhanced (CE) MRI. The hypovascularity and the increased arterial blood supply in well-defined CRLM were demonstrated by HRI. In CRLM-bearing mice, the entire liver perfusion was attenuated as the HRI maps were significantly reduced by 35%. This study demonstrates that the HRI method showed enhanced sensitivity for small CRLM (1–2 mm) detection compared with CE-MRI (82% versus 38%, respectively). In addition, HRI could demonstrate the vasculature alteration during CRLM progression (arborized vessels), which was further confirmed by histology. Moreover, HRI revealed the vascular changes induced by rapamycin treatment. Finally, HRI facilitates primary hepatic tumor characterization with good correlation to the pathologic differentiation. The HRI method is highly sensitive to subtle hemodynamic changes induced by CRLM and, hence, can function as an imaging tool for understanding the hemodynamic changes occurring during CRLM establishment, progression, and antiangiogenic treatment. In addition, this method facilitated the differentiation between different types of hepatic lesions based on their vascular profile noninvasively.  相似文献   
995.
Inhibition of the checkpoint kinase Chk1, both as a monotherapy and in combination with DNA damaging cytotoxics, is a promising therapeutic approach for the treatment of a wide array of human cancers. However, much remains to be elucidated in regard to the patient populations that will respond best to a Chk1 inhibitor and the optimal therapeutics to combine with a Chk1 inhibitor. In an effort to discover sensitizing mutations and novel combination strategies for Chk1 inhibition, an siRNA screen was performed in combination with the selective Chk1 inhibitor AR458323. This screen employed a custom made library of siRNAs targeting 195 genes, most of which are involved in cell-cycle control or DNA damage repair. One of the most prominent and consistent hits across runs of the screen performed in three different cancer cell lines was Wee1 kinase. MK-1775 is a small molecule inhibitor of Wee1 that is currently in early stage clinical trials. In confirmation of the results obtained from the siRNA screen, AR458323 and MK-1775 synergistically inhibited proliferation in multiple cancer cell types. This antiproliferative effect correlated with a synergistic induction of apoptosis. In cellular mechanistic studies, the combination of the two molecules resulted in dramatic decreases in inhibitory phosphorylation of cyclin-dependent kinases, an increase in DNA damage, alterations in cell-cycle profile, and collapse of DNA synthesis. In conclusion, the clinical combination of a Chk1 inhibitor and a Wee1 inhibitor holds promise as an effective treatment strategy for cancer.  相似文献   
996.
Oral Diseases (2010) 16 , 278–285 Aim: To evaluate the salivary carriage of Treponema denticola and its association with demographic variables in the etiopathogenesis of chronic periodontitis. Subjects and methods: Ninety‐seven chronic periodontitis (CP) patients and a control group of 51 healthy subjects (HC) were selected. Periodontal status was assessed by criteria based on probing depth, attachment loss, extent, and severity of periodontal breakdown. A polymerase chain reaction method was used to determine the occurrence of T. denticola in saliva samples. Risk indicators for CP were assessed individually and adjusted for confounding and/or interaction using a logistic regression model. Results: Although univariate analysis revealed a positive association of age ≥30 years, smoking, and salivary carriage of T. denticola with CP, after logistic regression analysis, the association between age ≥30 years/smoking and CP persisted, whereas salivary carriage of T. denticola failed to achieve statistical significance. An interaction effect was significantly detected between these three variables. Conclusion: Although salivary carriage of T. denticola may be a risk indicator for CP, its pathogenicity should not be exclusively endorsed to its detection in saliva, but it might be associated with the synergistic biological interaction of the bacterium with some demographic characteristics of the susceptible host.  相似文献   
997.
998.
Organic biomolecules that have retained their basic chemical structures over geological periods (molecular fossils) occur in a wide range of geological samples and provide valuable paleobiological, paleoenvironmental, and geochemical information not attainable from other sources. In rare cases, such compounds are even preserved with their specific functional groups and still occur within the organisms that produced them, providing direct information on the biochemical inventory of extinct organisms and their possible evolutionary relationships. Here we report the discovery of an exceptional group of boron-containing compounds, the borolithochromes, causing the distinct pink coloration of well-preserved specimens of the Jurassic red alga Solenopora jurassica. The borolithochromes are characterized as complicated spiroborates (boric acid esters) with two phenolic moieties as boron ligands, representing a unique class of fossil organic pigments. The chiroptical properties of the pigments unequivocally demonstrate a biogenic origin, at least of their ligands. However, although the borolithochromes originated from a fossil red alga, no analogy with hitherto known present-day red algal pigments was found. The occurrence of the borolithochromes or their possible diagenetic products in the fossil record may provide additional information on the classification and phylogeny of fossil calcareous algae.  相似文献   
999.

Background and purpose:

Indacaterol is a novel β2-adrenoceptor agonist in development for the treatment of chronic obstructive pulmonary disease. The aim of this study was to investigate the comparative pharmacology of indacaterol in recombinant cells expressing the common polymorphic variants of the human β2-adrenoceptor and in human primary airway smooth muscle (ASM) cells.

Experimental approach:

Chinese hamster ovarian-K1 cell lines expressing high and low levels of the common human β2-adrenoceptor variants were generated [Gly16-Glu27-Val34-Thr164(GEVT), RQVT, GQVT] and also the rare GQVI variant. Human primary ASM cells were isolated from explants of trachealis muscle. Adenosine-3′,5′-cyclic-monophosphate production was used as an outcome measure.

Key results:

In both the low- and high-expression recombinant GEVT ‘wild type’ cell lines indacaterol is a high-efficacy agonist. Salmeterol and formoterol were identified as low- and high-efficacy agonists, respectively, and showed similar potencies to indacaterol irrespective of the β2-adrenoceptor genotype. The I164 variant cell line was associated with a reduced capacity to generate adenosine-3′,5′-cyclic-monophosphate in response to β2-adrenoceptor agonist. In the human primary ASM cells indacaterol gave a maximal response intermediate between that of salmeterol and formoterol.

Conclusions and implications:

These data demonstrate that indacaterol is a high-efficacy agonist in recombinant cell systems but acts with lower efficacy in human primary ASM cells. No marked genotype-dependent effects were observed for common variants; however, changes in I164 receptor activity were identified, which were dependent on the level of expression of β2-adrenoceptors.  相似文献   
1000.

Background and purpose:

α- and β-amyrin are pentacyclic triterpenes found in plants and are known to exhibit pronounced anti-inflammatory effects. Here, we evaluated the effects of a 1:1 mixture of α- and β-amyrin (α,β-amyrin) on an experimental model of colitis in mice.

Experimental approach:

Colitis was induced in Swiss male mice by trinitrobenzene sulphonic acid (TNBS) and followed up to 72 h; animals were treated systemically with α,β-amyrin, dexamethasone or vehicle. Macro- and microscopic damage, myeloperoxidase activity and cytokine levels were assessed in colons. Histological sections were immunostained for cyclooxygenase-2 (COX-2), vascular endothelial growth factor, phospho-p65 nuclear factor-κB (NF-κB) and phospho-cyclic AMP response element-binding protein (CREB)

Key results:

TNBS-induced colitis was associated with tissue damage, neutrophil infiltration and time-dependent increase of inflammatory mediators. Treatment with α,β-amyrin (3 mg·kg−1, i.p.) or dexamethasone (1 mg·kg−1, s.c.) consistently improved tissue damage scores and abolished polymorphonuclear cell infiltration. α,β-Amyrin, like dexamethasone, significantly diminished interleukin (IL)-1β levels and partially restored IL-10 levels in colon tissues 72 h after colitis induction, but only α,β-amyrin reduced vascular endothelial growth factor expression by immunohistochemistry. The colonic expression of COX-2 at 24 h and that of phospho-NF-κB and phospho-CREB (peaking at 6 h) after colitis induction were consistently inhibited by both α,β-amyrin and dexamethasone.

Conclusions and implications:

Systemic administration of α,β-amyrin exerted a marked and rapid inhibition of TNBS-induced colitis, related to the local suppression of inflammatory cytokines and COX-2 levels, possibly via inhibition of NF-κB and CREB-signalling pathways. Taken together, our data suggest a potential use of α,β-amyrin to control inflammatory responses in bowel disease.  相似文献   
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