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61.
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In our search for new anticancer drugs, a series of binuclear ruthenium(III) thiosemicarbazone complexes of the type [RuCl2(EPh3)]2L (where E = P/As; L = binucleating monobasic tridentate thiosemicarbazone ligand) have been synthesized. Structural features were determined by various physico-chemical and spectral techniques. The interactions of these complexes with CT-DNA were investigated by absorption spectral study, indicates that the binuclear ruthenium(III) complexes form adducts with DNA and has intrinsic binding constant in the range of 1.0 × 104–7.9 × 104 M?1. The free radical scavenging activity of binuclear ruthenium(III) complexes have been determined by their interaction with the stable DPPH free radical. All the complexes exhibited significant antiproliferative activity against human breast cancer line, MCF-7. This research may provide knowledge that is an excellent backdrop for the rational design of promising drugs.  相似文献   
63.
Hip joint pain occurs not uncommonly in clinical practice. Arthritis of the hip joint, ligament strain and bursitis are some of the common causes of hip joint pain encountered by physicians. This article dwells on relevant clinical anatomy of the hip and the diagnostic approach to hip pain in rheumatology clinic.  相似文献   
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Ingested foreign bodies are a fairly common otorhinolaryngological emergencies encountered in Malaysia. The vast majority of these foreign bodies are fish bones which most commonly are impacted at the level of the cricopharynx. Rarely, however, a foreign body may migrate extraluminally and may even extrude subcutaneously. We report a rare occurrence where a fish bone not only migrated extraluminally, it was found to have migrated into the common carotid artery and the internal jugular vein and required surgical removal.  相似文献   
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BACKGROUND: Previous studies have investigated depression as the cause and outcome of vascular deficit in elderly persons. METHODS: The authors wanted to determine whether baseline depression is predictive of subsequent cardiovascular events in very elderly persons residing in a continuing care retirement community (n = 181). RESULTS: Controlling for demographic factors, both depression and the number of cardiovascular risk factors (CVRFs) at baseline were strongly predictive of stroke, whereas only CVRFs strongly predicted myocardial infarctions. Depression accounted for 12% of the variance in stroke incidence, beyond the contribution of CVRFs. Path analysis indicated that depression was also a partial moderator of the effect of CVRFs. CONCLUSIONS: In support of the vascular depression hypothesis, the study findings indicate that, for the oldest old, depression may be a strong predictor of future stroke. The presence of depression in elderly patients should alert physicians to carefully investigate other stroke risk factors and to integrate depression into an overall intervention regimen for reducing patients' risks for stroke.  相似文献   
68.
Prions are infectious protein conformations that are generally ordered protein aggregates. In the absence of prions, newly synthesized molecules of these same proteins usually maintain a conventional soluble conformation. However, prions occasionally arise even without a homologous prion template. The conformational switch that results in the de novo appearance of yeast prions with glutamine/aspargine (Q/N)-rich prion domains (e.g., [PSI+]), is promoted by heterologous prions with a similar domain (e.g., [RNQ+], also known as [PIN+]), or by overexpression of proteins with prion-like Q-, N-, or Q/N-rich domains. This finding led to the hypothesis that aggregates of heterologous proteins provide an imperfect template on which the new prion is seeded. Indeed, we show that newly forming Sup35 and preexisting Rnq1 aggregates always colocalize when [PSI+] appearance is facilitated by the [RNQ+] prion, and that Rnq1 fibers enhance the in vitro formation of fibers by the prion domain of Sup35 (NM). The proteins do not however form mixed, interdigitated aggregates. We also demonstrate that aggregating variants of the polyQ-containing domain of huntingtin promote the de novo conversion of Sup35 into [PSI+]; whereas nonaggregating variants of huntingtin and aggregates of non-polyQ amyloidogenic proteins, transthyretin, alpha-synuclein, and synphilin do not. Furthermore, transthyretin and alpha-synuclein amyloids do not facilitate NM aggregation in vitro, even though in [PSI+] cells NM and transthyretin aggregates also occasionally colocalize. Our data, especially the in vitro reproduction of the highly specific heterologous seeding effect, provide strong support for the hypothesis of cross-seeding in the spontaneous initiation of prion states.  相似文献   
69.
OBJECTIVES: To assess whether the clinical and laboratory methods for diagnosing Strongyloides stercoralis infection in non-endemic countries is different between those who are chronically exposed and those who travel. METHODS: Analysis of laboratory and clinical data from 204 patients having S. stercoralis infection at the Hospital for Tropical Diseases, London. RESULTS: Sixty-four travellers and 128 immigrants from endemic countries had laboratory-proven strongyloides. In those with microscopically proven disease, serology was 73% sensitive in travellers and 98% sensitive in immigrants (P < 0.001). There was no difference in the eosinophil count between the two groups with 19% having a normal count. Patterns of symptoms varied between the groups, and around one-third were asymptomatic in both groups. Serology was of limited use in follow-up. CONCLUSIONS: Eosinophil count and stool microscopy are insufficiently sensitive to be used alone for screening strongyloides. The sensitivity of serology is good in immigrants with chronic infection, but lower in travellers.  相似文献   
70.
Seventy-five patients with resistant acute leukemia or lymphoma received high-dose cyclophosphamide and etoposide to explore the activity of this combination in resistant hematologic malignancies, and to determine the maximum doses of these drugs that can be combined without bone marrow transplantation. Etoposide was administered over 29 to 69 hours by continuous infusion corresponding to total doses of 1.8 g/m2 to 4.8 g/m2. Cyclophosphamide, 50 mg/kg/d, was administered on 3 or 4 consecutive days total 150 to 200 mg/kg ideal body weight). At all dose levels myelosuppression was severe but reversible. Mucosal toxicity was dose-limiting with the maximum tolerated dose level combining etoposide 4.2 g/m2 with cyclophosphamide 200 mg/kg. Continuous etoposide infusion produced stable plasma levels that were lower than would be achieved after administration by short intravenous infusion, and this could explain our ability to escalate etoposide above the previously reported maximum tolerated dose. There were 28 complete (35%) and 12 partial (16%) responses. Median duration of complete response (CR) was 3.5 months (range 1.1 to 20+). Seventeen of 40 patients (42%) with acute myelogenous leukemia (AML) achieved CR, including 6 of 20 (30%) with high-dose cytosine arabinoside resistance. We conclude that bone marrow transplantation is not required after maximum tolerated doses of etoposide and cyclophosphamide. This regimen is active in resistant hematologic neoplasms, and the occurrence of CR in patients with high-dose cytosine arabinoside-resistant AML indicates a lack of complete cross-resistance between these regimens.  相似文献   
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