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1.
In light of the pharmacophoric structural requirements for achieving anticonvulsant activity, a series of N-(1-methyl-4-oxo-2-un/substituted-1,2-dihydroquinazolin-3[4H]-yl)benzamide (4a-g) and N-(1-methyl-4-oxo-2-un/substituted-1,2-dihydroquinazolin-3[4H]-yl)-2-phenylacetamide (4h-n) derivatives were synthesized in two steps starting from the reaction of N-methyl isatoic anhydride with the appropriate hydrazide and followed by condensation with the appropriate aldehyde. The anticonvulsant activities of the synthesized compounds were evaluated according to the anticonvulsant drug development (ADD) programme protocol. Among the synthesized compounds, 4n showed promising activity in both the maximal electroshock (MES) and pentylenetetrazole (PTZ) tests with median effective dose (ED50) values of 40.7 and 6 mg/kg, respectively. The six most promising derivatives, 4b , 4a , 4c , 4f , 4j , and 4i , showed very low ED50 values in the PTZ test (3.1, 4.96, 8.68, 9.89, 12, and 13.53 mg/kg, respectively). All the tested compounds showed no to low neurotoxicity in the rotarod test with a wide therapeutic index. Docking studies of compound 4n suggested that GABAA binding could be the mechanism of action of these derivatives. The in silico drug likeliness parameters indicated that none of the designed compounds violate Lipinski's rule of five and that they are able to cross the blood–brain barrier.
Hit, Lead & Candidate Discovery
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Background  

Heart chambers rupture in blunt trauma is uncommon and is associated with a high mortality. The determinant factors, and the incidence of isolated heart chambers rupture remains undetermined. Isolated rupture of the right atrium appendage (RAA) is very rare, with 8 cases reported in the reviewed literature. The thin wall of the RAA has been presumed to render this chamber more prone to rupture in blunt trauma.  相似文献   
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Several authors have questioned the potential for phrenic nerve paralysis with interpleural analgesia. This study was designed to examine the potential for phrenic nerve paralysis with the use of interpleural bupivacaine in dogs. Seven dogs were anesthetized, tracheally intubated, and allowed to breathe spontaneously with halothane/oxygen while in the supine position. After a midline laparotomy, two wires were inserted into the costal portion of each hemidiaphragm for measurement of electromyographic (EMG) signals. A balloon catheter was placed in the abdominal cavity to measure abdominal pressure. The abdomen was then closed. Airway pressure was measured through a side port in the endotracheal tube. Bilateral interpleural catheters were inserted with the loss-of-resistance technique. Each dog was used for two experiments, one on each side, except for one animal. To assess the contribution of the ipsilateral diaphragm to total respiratory effort, the airway was occluded at functional residual capacity for three consecutive breaths, and EMG, airway pressure, and abdominal pressure were measured. In five of nine experiments with bupivacaine, there was complete loss of EMG activity on the side of the injection. In two dogs, there was partial loss of diaphragmatic function, and in the remaining two, there was no change in EMG. In the normal saline solution group (n = 4), there was no change in the EMG. Two dogs that received bilateral bupivacaine injections developed paradoxical respiration with negative inspiratory intraabdominal pressures. Phrenic nerve paralysis or paresis can occur with interpleural blockade. The factors affecting the occurrence of this complication remain to be elucidated.  相似文献   
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c-Kit receptor (CD117) is expressed by erythroid, megakaryocytic, and myeloid precursors and mature mast cells and has been reported to be expressed in CD30+ lymphomas such as Hodgkin's disease and anaplastic large-cell lymphoma. Imatinib mesylate, a well-established inhibitor of bcr-abl tyrosine kinase, and currently used for the treatment of patients with chronic myeloid leukemia, also inhibits c-kit receptor kinase activity. In view of the possible use of imatinib as experimental therapy for patients with c-kit-positive tumors, we assessed c-kit expression in CD30+ cell lines and lymphomas. The cell lines were assessed using multiple methods (RT-PCR, flow cytometry, and Western blot). c-Kit expression was also immunohistochemically assessed in 168 CD30+ lymphomas including 87 classical Hodgkin's disease, 63 anaplastic large-cell lymphoma, and 15 cutaneous anaplastic large-cell lymphoma. We also studied 18 cases of lymphomatoid papulosis, a CD30+ lesion closely related to cutaneous anaplastic large-cell lymphoma. Neither c-kit mRNA nor protein was detected in any of the cell lines assessed. Furthermore, treatment with imatinib did not inhibit proliferation of cell lines in vitro. Using immunohistochemistry, only one of 183 (0.5%) lesions was positive for c-kit, the positive case being an ALK-negative anaplastic large-cell lymphoma. Our data demonstrate that expression of c-kit receptor is exceedingly rare among CD30+ lymphomas and lymphomatoid papulosis, suggesting that c-kit receptor is unlikely to be an appropriate target for therapeutic options such as imatinib in patients with these tumors.  相似文献   
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A review of the literature suggested that prolonged treatment time may lessen the probability of cure for patients with advanced squamous cell carcinoma of the upper aerodigestive tract. To shorten treatment time, rapid sequence treatment (RST) was devised in which chemotherapy, surgery, and irrada-tion were administered in a total treatment time of 8 weeks. Twelve patients were treated and followed 3 years or longer. Medical complications were minor. Osteonecrosis occurred in each of the first five patients and was the only major complication of the protocol. Surgical techniques were modified, and no additional patient developed osteonecrosis. No patient developed local or regional recurrence. Two patients developed distant metastases and three other patients developed second primaries. Absolute survival was 50%. Rapid sequence treatment is an aggressive and potentially hazardous protocol that yielded encouraging results in this pilot study.  相似文献   
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Women need to practice cervical screening regularly to reduce morbidity and mortality. The purpose of this study was to examine the impact of an intervention program on knowledge, attitude, and practice of cervical screening in the population of Lebanese/Armenian women. The design was a cross-sectional, quasi-experimental posttest survey following a year long intervention program. The sample included 176 women, who were members of the Armenian Relief Cross in Lebanon. Interventions consisted of educational classes, media messages, and free screening. The instrument was a self-administered questionnaire. Knowledge of women with intervention was higher (p > .05) and practice rate increased between intervention and comparison groups. No difference in attitude was noted. The study was successful in raising awareness and increasing screening in the sample. It is recommended to continue helping women to overcome barriers for cervical screening.  相似文献   
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