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51.
The maximum watts factor (WFmax) is often used to characterize detrusor contractility. It was recently shown that the WFmax may increase in some patients with chronic outlet obstruction. It is, however, unclear whether this increase reflects a dependence of the WFmax on the degree of outlet obstruction or whether it represents a true increase in detrusor contractility secondary to chronic outlet obstruction. Therefore, this study was performed to investigate this issue using a canine model of acute outlet obstruction. Urodynamic studies were performed on adult canines with surgically exposed lower urinary tracts. Pressure transducers were used to measure the intravesical and the distal urethral pressures, whereas an ultrasonic flow meter was used to obtain a simultaneous measure of the urinary flow rate. Detrusor contractions were induced by electrically stimulating the pelvic nerves bilaterally. Varying degrees of outlet obstruction were created using an inflatable sphincter cuff secured around the bladder outlet. The WFmax, the detrusor pressure at voiding terminus (Pdet.clos), and the passive urethral resistance (R) were computed from measured pressure-flow rate data at each degree of outlet obstruction. The WFmax was not significantly correlated to either the sphincter cuff volume (r = 0.025, p = 0.871), the Pdet.clos (r = 0.286, p = 0.073) or the R (r = 0.110, p = 0.509). The WFmax was not significantly different among mild, moderate, and severe degrees of outlet obstruction (p = 0.176). Our results suggest that the WFmax is independent of the degree of acute outlet obstruction (defined in terms of the sphincter cuff volume, Pdet.clos and R). This validates the current practice of using the WFmax to evaluate detrusor function in patients with voiding dysfunction regardless of outlet resistance. Further, since the WFmax is independent of outlet obstruction acutely, it is reasonable that it would also be independent of outlet obstruction under chronic conditions. Our results, therefore, also imply that the increase in the WFmax with chronic outlet obstruction may represent a true increase in detrusor contractility and not a WFmax dependence on outlet resistance.  相似文献   
52.
The choice of empirical treatment for community-acquired pneumonia (CAP) is highly controversial. Our survey of 42 Australian emergency department doctors showed that monotherapy with a third-generation cephalosporin was the preferred regimen for severe CAP (14/42; 33%). We argue that cheaper regimens with a narrower spectrum are likely to be just as effective as third-generation cephalosporins and will have fewer adverse effects on the microbial ecology of hospitals. We suggest penicillin or ampicillin (to cover pneumococci--even if penicillin "resistant"--and Haemophilus influenzae), plus a macrolide (e.g., azithromycin or erythromycin; to cover Legionella and other "atypical" pathogens), plus a single large dose of an aminoglycoside (e.g., gentamicin; to cover gram-negative bacilli such as Klebsiella pneumoniae) as empirical therapy for severe CAP.  相似文献   
53.
OBJECTIVE: A summary about the final results of the Hungarian double-blind placebo controlled randomised trial of periconceptional folic acid containing multivitamin and trace element supplementation. RESULTS: The major finding is a significant prevention of the first occurrence of neural-tube defect, urinary tract and cardiovascular defects, in addition a decrease in the rate of limb deficiencies and congenital hypertrophic pyloric stenosis. Fertility was slightly improved and the rate of twins increased significantly after periconceptional multivitamin supplementation. The effect of multivitamin supplementation for fetal death is controversial, but in general there is no clinically significant change. Periconceptional multivitamin supplementation can reduce the occurrence of nausea and vomiting. PRACTICAL IMPLEMENTATIONS: Consumption of foods which are rich in folate may not be the best way to prevent neural-tube defects and other congenital abnormalities. Periconceptional multivitamin supplementation is part of the periconceptional care in Hungary and it is an appropriate forum for the practical delivery for this primary prevention action. However, as a large proportion of pregnancies are unplanned, the widespread use of bread fortified with folic acid, vitamin B12 and B6 may decrease a considerable part of neural-tube defects and some other congenital abnormalities, in addition to vascular diseases due to hyperhomocysteinemia.  相似文献   
54.
BACKGROUND: Despite their potential therapeutic benefit, the effects of cholinergic agents on anal function have been poorly investigated. AIM: To analyse the effects of neostigmine and atropine on anorectal responses to rectal isobaric distension. METHODS: This was a placebo-controlled, randomized, double-blind crossover study, performed in 12 healthy volunteers who received intravenously, on 3 separate days, neostigmine, atropine or the placebo. During each day of the experiment, seven pressure steps (ranging from 1 to 31 mmHg) in three different protocols of rectal isobaric distension (phasic, stepwise and tonic) were applied using an electronic barostat. Manometric responses of the anal canal, adaptative volumes and perception scores of the rectum were recorded. RESULTS: During stepwise distension, a significant drug effect was encountered at the anal level. No drug effect was observed on the other investigated parameters (rectal volumes and rectal perception scores) or for the other modes of distension. Compared to placebo, neostigmine significantly decreased pressures at the upper level of the anal canal for both recto anal inhibitory reflex and mean resting pressures. In contrast, atropine significantly increased pressures at the lower part of the anal canal but did not modify upper anal pressures. CONCLUSION: The present study suggests that cholinergic effects result more from an indirect action on intermediate neurotransmitters and rectal myenteric neurons, than from a direct action on anal targets.  相似文献   
55.
The ETV6 (TEL) locus at chromosome band 12p 13 is a major site of translocations in acute leukemia, particularly in childhood acute lymphoblastic leukemia (ALL). In cases with translocations involving ETV6, the normal ETV6 allele is often deleted. In addition, loss of heterozygosity of ETV6 is frequently observed in childhood'ALL. Thus, it has been suggested that ETV6 may have an anti-oncogenic role to play, in addition to its oncogenic role. We have described an unusual case of ALL in which ETV6 is found fused to the ABL gene; ABL is normally activated by fusion to the BCR gene in the 9:22 translocation. We expanded the primary cells from this ETV6/ABL rearranged case of ALL in SCID animals and analyzed them for expression of both ETV6/ABL and the normal ETV6 mRNA. We found that both the rearranged and normal ETV6 mRNAs are expressed in the expanded cell population. Furthermore, sequence analysis of the ETV6 PCR product revealed no point mutations which would influence the amino acid sequence. Thus, deletion of the second ETV6 allele is not necessary for the transformation to leukemia by ETV6/ABL.  相似文献   
56.
A focus on the importance of leisure in the development of student nurses has been neglected in the 1990s. This study considers 444 prospective nurses on conventional, diploma and degree courses in two areas of England. It examines their activities associated with socializing, their social support networks and their use of clubs, sports and hobbies before entering nursing. It is evident that students enter nurse training with a wide variety of leisure experiences. Changing recruitment patterns and the structure of nurse training has an effect on the leisure needs of prospective nurses which must be addressed.  相似文献   
57.
58.
OBJECTIVES: Previous studies of surgical treatment for cervical dystonia have reported highly variable rates of postoperative symptomatic benefit and morbidity. Little is known about functional improvement and long term results. This study evaluates the symptomatic and functional outcome of surgical treatment of cervical dystonia in a consecutive series of 46 patients. METHODS: The most affected muscles were selected for denervation after clinical examination and confirmation by four channel EMG studies. Surgical treatment, aiming at selective elimination of pathological activity while preserving normal motor function and avoiding side effects, was achieved by using a broad scope of techniques including intradural denervation, extradural denervation, and myotomy. Rather than carrying out standard operations, the treatment was tailored to the needs of the patient according to the individual pattern of dystonic activity. Long term benefit was assessed with a global outcome score, and a modified Toronto western spasmodic torticollis rating scale (TWSTRS) in those 34 patients who were available for a recent follow up evaluation. RESULTS: The 46 patients underwent a total of 70 procedures with intradural approaches in 33 instances, extradural approaches in 21, and muscle sections (singly or combined) in 22 instances. Transient mild postoperative side effects occurred in 10% of the procedures. The mean duration of long term follow up was 6.5 years. The global outcome was rated as excellent in nine patients (21%), as marked in 12 (27%), as moderate in nine (21%), as mild in nine (21%), and as no improvement in five (11%). A persistent side effect consisting of mild difficulty with balance was noted in one case. There were highly significant changes of the preoperative and postoperative mean values for almost all TWSTRS subscores for severity of cervical dystonia, functional disability, and pain. Patients with excellent outcome underwent a higher number of surgical procedures on average than those patients who achieved no benefit. CONCLUSIONS: Surgical treatment tailored to the specific pattern of dystonic activity in the individual patient is a valuable alternative in the long term management of cervical dystonia.  相似文献   
59.
BACKGROUND: Concern about the 8 to 10 cases per year of vaccine-associated paralytic poliomyelitis caused by the live oral poliovirus vaccine (OPV) has led to revised guidelines for immunization of children in the United States. The use of inactivated poliovirus vaccine (IPV) at 2 and 4 months of age could require administration of 3 injections per visit until combination products are available. OBJECTIVE: To determine parents' knowledge of poliovirus vaccines and the choices they would make between IPV and OPV. METHODS: Parents of 240 children aged 2 weeks to 18 months under the care of 10 private pediatricians in the Baltimore, Md, metropolitan area were interviewed prior to the announcement of revised advisory committee guidelines. RESULTS: The majority (62.5%) of respondents were not aware that 2 poliovirus vaccines are available. After reviewing standardized information about the vaccines and 2 alternate schedules, most (75%) parents would consult someone (primarily their physician) before making a final choice of a vaccine schedule. If parents made the choice without consulting anyone else, 61.3% would choose to have their child receive IPV and 3 injections per visit as compared with an all-OPV schedule and 2 injections per visit. Inactivated poliovirus vaccine was preferred by most parents because it would reduce the risk for vaccine-associated paralytic poliomyelitis. Oral poliovirus vaccine was preferred by 37.9% of parents primarily because it was given orally. If the number of injections at each visit was the same for both vaccines, 76.3% of parents would choose the IPV schedule, and if the number of injections was reduced to 2 by combining IPV with another vaccine, 87.9% of parents would choose IPV. CONCLUSION: The number of injections per visit is an important issue, but a majority of parents would choose to have their children receive extra injections to prevent the low risk for vaccine-associated paralytic poliomyelitis.  相似文献   
60.
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