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71.
New heterocyclic compounds containing pyrazol-5-one coupled with benzimidazole, benzothiazole, benzoxazole, quinoline, naphthyridin, and pyrazole were synthesized. Comparative investigations to synthesize these interesting classes of heterocyclic compounds through conventional heating or under microwave-irradiation conditions were presented. Synthesized compounds 1a, 2a, 4k, 3a, c, 5a, b, 6b, 7a, b, d, 8a, and 9a were evaluated for their antitumor activity. Some of these compounds exhibited promising antitumor activity.  相似文献   
72.
This article provides information and a commentary on trials relevant to the pathophysiology, prevention, and treatment of heart failure presented at the annual meeting of the European Society of Cardiology held in Barcelona in 2009. The AAA study does not support the routine use of aspirin for the prevention of vascular events in patients with asymptomatic atherosclerosis. RELY suggests that dabigatran may be more effective than warfarin for the prevention of stroke in patients with atrial fibrillation. Rolofylline was not superior to placebo in improving outcomes in patients with acute heart failure enrolled in the PROTECT study, but dyspnoea was improved. Data from ACTIVE‐I suggest that irbesartan does not provide additional therapeutic benefit in patients with atrial fibrillation who are well controlled on current therapy. The European cardiac resynchronization therapy (CRT) survey provides interesting epidemiological data on current CRT device usage. The German pre‐SCD II registry identified a low prevalence of patients with a reduced ejection fraction following myocardial infarction. Implantation of CRT‐D rather than an implantable cardioverter defibrillator in patients with mild heart failure and QRS ≥130 ms reduced the risk of hospitalization for heart failure in MADIT‐CRT; mortality was similarly low with each device.  相似文献   
73.
Concurrent existence of multiple developmental dental anomalies: hypodontia of permanent mandibular incisors, dentin dysplasia, transmigration, root dilaceration, ectopic eruption and delayed eruption combined with systemic abnormalities including joint hyperlaxity and skin hyperextensibility aided in diagnosis of a sporadic case of hypermobility type of Ehlers-Danlos syndrome in a Jordanian Arab male. In dental practice the presence of multiple developmental dental anomalies expressing simultaneous defects in different stages of tooth development should raise suspicion of possible of manifestation of an underlying systemic abnormality.  相似文献   
74.
A 29-year-old man was admitted with high-grade fever, crampy abdominal pain, and watery diarrhea that had persisted for 2 weeks before his admission. Symptomatic treatment (acetaminophen only) was of no benefit. On physical examination, there was diffuse abdominal tenderness. Laboratory tests showed a leukomoid reaction with atypical lymphocytosis, and serology tests revealed acute cytomegalovirus infection. Abdominal computed tomography and colonoscopy revealed an inflammatory process involving the large intestine. On histologic examinations of intestinal biopsy samples, there was an active inflammation with no inclusion bodies.The patient was treated with ganciclovir with only mild improvement. Adding 5-aminosalicylic acid caused little further improvement. Repeated colonoscopy performed 2 months later showed severe chronic ulcerative colitis. Only the addition of systemic steroids caused complete resolution of the symptoms.On review of the literature (Medline search for cytomegalovirus colitis in immunocompetent patients), 18 cases were found. On follow-up, 10 of these patients were found to have inflammatory bowel disease.  相似文献   
75.

Introduction  

Many herbal medicinal products have potential hypocholesterolaemic activity and encouraging safety profiles. However, only a limited amount of clinical research exists to support their efficacy.  相似文献   
76.
Sustained-release diclofenac potassium orally disintegrating tablet (ODT) formulations have been prepared and investigated. The ODTs were prepared by incorporating diclofenac potassium (DP), as a model for negatively ionizable drugs, in microcapsules that were prepared by the solvent evaporation method from a mixture of DP and different ratios of Eudragit RS and Eudragit RL, which are positively ionized synthetic polymers. The ODTs were prepared by direct compression of mixtures containing microcapsule formula M4, crospovidone as a superdisintegrant and water soluble excipients (mannitol or lactose and sorbitol). Diclofenac potassium ODT F2, showed acceptable hardness (4.08 KP) slight friability (2.13 %) and disintegration time of 22.41 s with a sustained drug release profile. Microcapsule characterization (DSC and FT-IR) and dissolution behavior suggests the presence of specific interaction between the carboxylate group of diclofenac and the quaternary ammonium group in the polymers  相似文献   
77.
Germ line gain-of-function mutations in several members of the RAS/ERK pathway, including PTPN11, KRAS, and RAF1, cause the autosomal dominant genetic disorder Noonan Syndrome (NS). NS patients are at increased risk of leukemia/myeloproliferative disease and possibly some solid tumors, such as neuroblastoma. Recently, SOS1 gain of function mutations have also been shown to cause NS. Somatic PTPN11, KRAS, and RAF1 mutations occur (although at different frequencies) in a variety of sporadic neoplasms, but whether SOS1 mutations are associated with human cancer has not been evaluated. We sequenced DNA from a total of 810 primary malignancies, including pancreatic, lung, breast, and colon carcinomas, and acute myelogenous leukemia, as well as several neuroblastoma cell lines. From this large, diverse series, missense SOS1 mutations were identified in a single pancreatic tumor, one lung adenocarcinoma, and a T-cell acute lymphoblastic leukemia cell line. Our findings suggest that SOS1 is not a significant human oncogene in most cancers. Furthermore, NS patients with SOS1 mutations may not be at increased risk of developing cancer.  相似文献   
78.
79.
Mitochondria have their own translational machineries for the synthesis of thirteen polypeptide chains that are components of the complexes that participate in the process of oxidative phosphorylation (or ATP generation). Translation initiation in mammalian mitochondria requires two initiation factors, IF2(mt) and IF3(mt), instead of the three that are present in eubacteria. The mammalian IF2(mt) possesses a unique 37 amino acid insertion domain, which is known to be important for the formation of the translation initiation complex. We have obtained a three-dimensional cryoelectron microscopic map of the mammalian IF2(mt) in complex with initiator fMet-tRNA(iMet) and the eubacterial ribosome. We find that the 37 amino acid insertion domain interacts with the same binding site on the ribosome that would be occupied by the eubacterial initiation factor IF1, which is absent in mitochondria. Our finding suggests that the insertion domain of IF2(mt) mimics the function of eubacterial IF1, by blocking the ribosomal aminoacyl-tRNA binding site (A site) at the initiation step.  相似文献   
80.
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