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41.
Securinega virosa is used traditionally as sedative in children and in mental illnesses. In this study, the behavioral effects of methanolic root bark extract of S. virosa were investigated in mice. The results revealed that the extract significantly (P<0.05) and dose-dependently reduced the onset and prolonged the duration of sleep. The extract significantly (P<0.05) decreased exploratory activity and reduced the rate of apomorphine-induced stereotyped climbing at the doses tested (6.25–25mg/kg). It also produced a significant and dose-dependent motor coordination deficit in mice at the doses tested (P<0.01). The intraperitoneal median lethal dose in mice was 774.6mg/kg while the preliminary phytochemical screening revealed the presence of alkaloids, tannins, saponins and flavonoids. These results suggest that methanolic root bark extract of S. virosa contains biologically active principles that are sedative in nature and lend pharmacological credence to the ethnomedical use of the plant.  相似文献   
42.
The synthesis of two novel drugs, 4-[bis[2-(mesyloxy)ethyl]amino]benzoic acid (7) and 4-[(2-chloroethyl)[2-(mesyloxy)ethyl]amino]benzoic acid (8) is described here. They are the active drugs of two prodrugs (9 and 10) designed for use as anti-cancer agents. The prodrugs (9, 10 and 11) were made as a series of compounds which are bifunctional alkylating agents in which the activating effect of the ionized carboxyl function is masked through an amide bond to a glutamic acid residue. These relatively inactive prodrugs were designed to be activated to their corresponding alkylating agent active drugs (7, 8 and 12 respectively) at a tumour site by prior administration of a monoclonal antibody conjugated to a bacterial enzyme. This system is called antibody-directed enzyme prodrug therapy (ADEPT). The chemical half-lives of the prodrugs and their active drugs were measured in order to determine their relative reactivities. The half-lives ranged from 21 to 324 min for the active drugs and from 42 to 1158 min for the prodrugs. The viability of two different tumour cell lines was monitored with each active drug and prodrug. The IC50 values varied from 65 to 625 microM for the active drugs: no IC50 values could be obtained for the prodrugs, using a rapid incubation procedure. Each in vitro technique demonstrated the ability of the glutamic acid moiety to deactivate the drugs, forming effective prodrugs.  相似文献   
43.
Background Many therapeutic modalities have been suggested for treatment of the chronic hand eczema. Despite good immediate efficacy of some of these treatments, there is high recurrence of the dermatitis following cessation of the treatment. Aim Regarding the beneficial effects of the zinc sulfate on the skin, we designed a double blind study to evaluate the efficacy of the ‘0.05% Clobetasol + 2.5% zinc sulphate’ cream versus ‘0.05% Clobetasol alone’ cream in the treatment of the chronic hand eczema. Subjects and Methods This study was a double‐blind, right to left, prospective, clinical trial. In total, 47 patients with chronic hand eczema admitted to dermatology center of Isfahan University of Medical Sciences were selected and their right hand or left hand were selected at random to be treated with either the ‘0.05% Clobetasol + 2.5% zinc sulphate’ cream or ‘0.05% Clobetasol alone’ cream twice daily for 2 weeks. All of the patients were treated for 2 weeks and were followed up at weeks 2, 4, 6 and 8 after starting the treatment. For determining the severity of chronic hand eczema, we assessed and scored 4 different characteristics of the lesions including redness; scaling; lichenification and pruritus. The data were analyzed using SPSS program (release 13) and statistical tests including Mann‐Whitney test. Results Overall, 47 patients (94 samples) were evaluated. All of these patients had similar and symmetrical lesions on their right and left hands. Out of them, 35 patients were females and 12 patients were male. In all of the evaluated characterisitics, the ‘0.05% Clobetasol + 2.5% zinc sulphate’ cream was more effective than ‘0.05% Clobetasol alone’ cream (P < 0.05). The recurrence rate of eczema was significantly lower in the group treated with this combination treatment (P < 0.05). Conclusion With regard to the encouraging results of the combination treatment with Clobetasol + zinc sulphate, we suggest that in a more extensive clinical trial, the efficacy of this treatment against chronic hand dermatitis be evaluated. In addition, evaluation of this combination therapy against other inflammatory dermatosis seems to be logical.  相似文献   
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45.
Smith  TP; Cragg  AH; Berbaum  KS 《Radiology》1989,170(3):941
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46.
Background  Alopecia areata is a complex genetic disease with still many unknown aspects, and many studies have been tried to find some clues about it.
Objective  We aimed to investigate the demographic and clinical characteristics of alopecia areata in Turkish patients.
Methods  Demographic data, localization, attack number in addition to some parameters such as disease duration, severity, age of onset, family history and ophiasis pattern were evaluated in 539 alopecia areata patients.
Results  The male to female ratio was 1.6 : 1. Occipital and beard-moustache areas were mostly affected. Positive family history was noticed in 24.1% of the patients. The age of onset was earlier in women than in men ( P =  0.04). Severe forms showed more persistent (≥ 1 year) disease duration ( P =  0.00). Ophiasis was more common in severe, long duration (≥ 1 year) and early onset (≤ 18 years) disease ( P =  0.00 for all parameters). Childhood alopecia areata (≤ 18 years) was also associated with long duration of the disease ( P =  0.016) and positive family history ( P =  0.008) when compared with adult onset (> 18 years) alopecia areata.  相似文献   
47.
Vascular endoprostheses made of knitted tantalum wire and expanded over angioplasty balloons were placed into aortas or iliac arteries of 14 normal dogs. Twelve stents were placed into the infrarenal abdominal aorta and two stents in the left common iliac arteries by the left carotid artery approach. To firmly expand the stent against the vascular wall, nominal stent sizes 0.5-1.0 mm larger than the measured arterial diameter were required. Arteriography performed at specified follow-up intervals showed no evidence of thrombi or emboli; all side branches (lumbar arteries) covered by the stents remained patent. Vascular diameter decreased minimally at 8 and 26 weeks, associated with histopathologic evidence of neointimal buildup. This buildup was highest at 8 weeks (mean, 313 microns) and was slightly less at 26 weeks (mean, 223 microns). Almost complete coverage by endothelium was seen as early as 3 weeks. It is concluded that the flexible tantalum wire stents are well tolerated by the arterial wall and become quickly endothelialized. No excessive neointimal buildup was observed during the 6-month study.  相似文献   
48.
The radiographic findings in five pediatric patients in whom unregulated B-cell lymphoproliferative disorders developed following bone marrow transplantation are described. Four patients received T-cell-depleted bone marrow from mismatched donors and one received nondepleted marrow from a matched sibling donor. These disorders are similar to B-cell lymphoproliferative disorders that have been described in other immunosuppressed hosts. They are associated with Epstein-Barr virus and range from polyclonal proliferation without cytogenetic abnormalities to monoclonal lymphoma with clonal cytogenetic changes. Unlike other postallograft lymphoproliferative processes, B-cell lymphoproliferative disorders in these patients have not responded to antiviral therapy, immunologic therapy, or chemotherapy. The radiographic patterns of disease include diffuse or focal hepatic involvement; gallbladder wall thickening; and pulmonary, soft-tissue, and basal-ganglion masses. These radiologic findings are not specific and evaluation of tissue histology is required for diagnosis.  相似文献   
49.
50.

Background  

DNA fingerprinting of Mycobacterium tuberculosis isolates offers better opportunities to study links between tuberculosis (TB) cases and can highlight relevant issues in urban TB control in low-endemic countries.  相似文献   
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