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81.
The protozoan parasite Trypanosoma brucei relies on trans-splicing of a common spliced leader (SL) RNA to maturate mRNAs. Using the yeast two-hybrid system a protein (TSR1IP) was identified that interacts with the T. brucei serine-arginine (SR) protein termed TSR1. TSR1IP shows homology to U1 70 kDa proteins, and contains an SR rich domain as well as an acidic/arginine domain homologous to the U1 70 kDa poly(A) polymerase inhibiting domain. This protein is localized in the nucleoplasm and excluded from the nucleolus in trypanosomal bloodstream and procyclic forms. Based on structural modelling predictions and on the identification of a RNA recognition motif (RRM), it was possible to demonstrate by the yeast three-hybrid system that TSR1IP interacts with the 5' splice region of the SL RNA. All the above characteristics suggest that TSR1IP could be involved in trans-splicing.  相似文献   
82.
A number of treatments are widely prescribed for chronic back pain, but few have been rigorously evaluated. We examined the effectiveness of transcutaneous electrical nerve stimulation (TENS), a program of stretching exercises, or a combination of both for low back pain. Patients with chronic low back pain (median duration, 4.1 years) were randomly assigned to receive daily treatment with TENS (n = 36), sham TENS (n = 36), TENS plus a program of exercises (n = 37), or sham TENS plus exercises (n = 36). After one month no clinically or statistically significant treatment effect of TENS was found on any of 11 indicators of outcome measuring pain, function, and back flexion; there was no interactive effect of TENS with exercise. Overall improvement in pain indicators was 47 percent with TENS and 42 percent with sham TENS (P not significant). The 95 percent confidence intervals for group differences excluded a major clinical benefit of TENS for most outcomes. By contrast, after one month patients in the exercise groups had significant improvement in self-rated pain scores, reduction in the frequency of pain, and greater levels of activity as compared with patients in the groups that did not exercise. The mean reported improvement in pain scores was 52 percent in the exercise groups and 37 percent in the nonexercise groups (P = 0.02). Two months after the active intervention, however, most patients had discontinued the exercises, and the initial improvements were gone. We conclude that for patients with chronic low back pain, treatment with TENS is no more effective than treatment with a placebo, and TENS adds no apparent benefit to that of exercise alone.  相似文献   
83.
Summary Twenty three patients with essential hypertension who were uncontrolled on diuretic and/or -receptor antagonist therapy were treated additionally with the vasodilator, pinacidil, in an open study. Significant reduction in mean blood pressure was achieved. Supine and erect systolic and diastolic blood pressure fell by 44/25 mmHg and 37/24 mmHg respectively over the study period of 12 weeks. Side-effects such as dizziness, headache, facial flushing and mild oedema were experienced by 10 patients during the study, all of which were mild and transient and did not require withdrawal from pinacidil therapy. Pinacidil is an effective and well tolerated agent in the treatment of essential hypertension.  相似文献   
84.
Summary The expression of transferrin receptors (TFR) by normal and neoplastic urothelial cells was studied in control patients and in patients with transitional cell carcinoma of the bladder. These tumours were graded independently and consisted of 19 grade I, 30 grade II and 19 grade III lesions. TFRs were identified using a monoclonal antibody specific for TFR (OKT9) in an immunofluorescent or avidin/biotin-immunoperoxidase technique on fresh frozen sections. TFRs were not detected on normal urothelium. However, positive staining was found to increase with increasing pathological grade and stage of the tumours, ranging from 31.6% of grade I to 78.9% of grade III tumours and 51.2% of pTa (mucosa only lesions) to 87.5% of pT2/pT2+ (muscle invasion±deeper) primary urothelial malignancies.  相似文献   
85.
The behavioral effects following intrastriatal MPP+, the neurotoxic metabolite of MPTP, were evaluated in mice. Bilateral injections of 10 cro;g MPP+ to mice previously trained in the shuttle box paradigm produced a 66% decrease in striatal dopamine and significant deficits in all measures of conditioned avoidance responding. In addition, although these mice showed no deficits in baseline rotorod performance, challenge with the cholinergic agonist oxotremorine revealed that MPP+-treated mice exhibited an increased sensitivity to the disruptive effects of the drug at each dose and time point. Finally, MPP+-treated mice also exhibited an increase in tremor induced by 0.1 and 0.15 mg/kg oxotremorine. These observations are discussed in reference to idiopathic parkinsonism.  相似文献   
86.
This paper compares evaluative research to program evaluation by defining and describing each. A case example using the scientific design and methodology of evaluative research to evaluate a specific community mental health program is also presented. Project design is discussed in light of the awareness that the mental health needs of communities do not always bend to fit the requisite of precise scientific procedure. Some ideas on methodological considerations reflect that normal research tools can be useful to achieve a valid study. Implications for the application of evaluative research to community mental health needs are also identified.  相似文献   
87.
Maternal and Child Health Journal - The purpose of this study was to explore socio-ecological influences affecting the daily lives of urban, pregnant Puerto Rican women and factors negatively...  相似文献   
88.

Background  

The longterm outlook afterHelicobacter pylori (H. pylori) eradication in peptic ulcer disease is unclear.  相似文献   
89.
Management of intra-articular calcaneal fractures remains a debated topic in orthopedics, with operative fixation often held in reserve due to concerns regarding perioperative morbidity and potential complications. The purpose of this study was to identify the characteristics of patients who developed surgical complications to inform the future stratification of patients best suited to operative treatment for intra-articular calcaneal fractures. All patients who underwent open reduction and internal fixation of calcaneal fractures utilizing the Sinus Tarsi approach between March 2014 and July 2018 were identified using theatre records. Patient imaging was used to assess pre- and postoperative fracture geometry with computed tomography used for preoperative planning. Each patient's clinical presentation was established through retrospective analysis of medical records. Patients provided verbal consent to participation and patient reported outcome measures were recorded using the Maryland Foot Score. Fifty-eight intra-articular calcaneal fractures (53 patients; 5 bilateral, mean age = 46.91 years) with a mean follow-up of 35.4 months (6-57) were included. Five patients (9.4%) had wound complications; 2 superficial (3.7%), 3 deep (5.6%); 4 of whom were smokers. Smokers were statistically more likely to have wound infections than nonsmokers (p = .04). Intra-articular fractures of the calcaneus should be considered for surgical intervention in order to improve long-term functional outcomes. The Sinus Tarsi approach provides the potential to decrease the operative complication rate whilst maintaining adequate fixation, however, the decision to surgically manage these fractures should be carefully balanced against the risk of postoperative complications. This increased risk of complication associated with smoking may tip the balance against benefit from surgical management.  相似文献   
90.
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