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991.
OBJECTIVE: To evaluate the role of the nurse practitioner in urology and to determine the impact on the work of junior doctors. METHODS: Written criteria were defined before the postholder was appointed and subsequent performance was assessed against these criteria. Training was provided and the quality of work was assessed by direct observation. Senior House Officers (SHOs) were asked whether the post had increased their opportunities to attend theatre, outpatients and post-graduate training sessions and had decreased the number of 'inappropriate' tasks they had to perform. RESULTS: The nurse practitioner accomplished all the tasks that were defined before the appointment. The assessment of patients in pre-admission and haematuria clinics was satisfactory. The continuity of information, care of patients and counselling for patients receiving complex surgery were improved. Sixty-three per cent of all patients seen in the pre-admission clinic and all patients in a haematuria clinic were assessed initially by the nurse practitioner. Because the nurse practitioner was involved in setting up intravenous drug administration and infusions, administrative tasks and in obtaining results from the laboratory, the number of 'inappropriate' tasks performed by the SHOs decreased and they were able to attend more sessions of training and education. CONCLUSIONS: The nurse practitioner in clinical urological practice constitutes an effective use of resources and relieves junior medical staff from other tasks, allowing them to receive a more focused training. In addition, the quality of patient care was thought to be improved in some areas. The framework of a job plan for a nurse practitioner is described.  相似文献   
992.
Giant cell tumor is a locally aggressive tumor with a high recurrence rate if not completely excised. The condition is more common among Asians than whites. During a 10-year period 44 patients, ranging in age from 12 to 51 years, were treated. The most common sites were the proximal femur and the distal radius. The aim of treatment was to excise the tumor completely. Because the tumor usually occurred at the juxtaarticular region of the bone, difficult reconstruction was expected. The authors' method of choice for filling large defects resulting from resection was to use a large vascularized bone graft from the iliac crest to enhance bone to bone corporation. The recurrence rate was low (4.5%), with only 2 recurrences: 1 at the proximal femur and the other at the proximal tibia. The functional results were highly satisfactory, with excellent stability of the joint, although in the case of the distal radius there was some degree of subluxation of the wrist joint. By applying microsurgical technique for the reconstruction, one was able to be more aggressive with excision of this locally aggressive tumor while maintaining excellent functional results. In the case of the knee, as long as 1 tibial condyle was intact, reconstruction of the other condyle using a vascularized iliac crest block maintained the joint integrity perfectly or created a pseudojoint component that was perfectly stable.  相似文献   
993.
Freshwater mussels Anodanta anatina and Pseudanodonta complanata were exposed to (14C)-pentachlorophenol. The wet weight based bioconcentration factor (BCF = activity in animal per activity in water) at steady state varied from 80 to 120 for A. anatina and from 61 to 85 for P. complanata. The species did not differ significantly in their wet weight or lipid based BCFs but dry weight based values were significantly higher (40-50%) for A. anatina. The soft tissue dry weight and dry weight based condition index of A. anatina (Cl4 = soft tissue dry weight per shell length) differed significantly between natural mussel populations. In animals kept from 4 to 8 months in laboratory conditions, the soft tissue dry weight and glycogen content decreased more rapidly when mussels were maintained at 15 than at 5 degrees C. However, glycogen content in the digestive gland or adductor muscle did not differ in mussels maintained in the laboratory (5 degrees C) when compared to the natural population. The adductor muscle protein content differed between laboratory maintained animals and the natural population in Lake H?yti?nen but there was no difference in the soft tissue lipid content. Trace metal concentrations and calcium in the soft tissue were in general higher in laboratory maintained mussels. In addition, laboratory maintenance affected the reproductive cycle of A. anatina.  相似文献   
994.
995.
996.
The dynamic substructure method is extended to lightly or heavily damped systems. Both internal and external dampings are considered. The damped dynamic flexibility associated with the slave co-ordinates is first expanded in terms of the damped fixed interface natural modes and the condensed dynamic stiffness associated with the master co-ordinates is formed subsequently. The convergence of the condensed dynamic stiffness with respect to the damped natural modes can be improved by means of the static matrices. Since the dynamic stiffness method is equivalent to the modal synthesis method, the component mode method and Kron's method, the theory presented here is readily applicable to these methods are restricted to symmetric damping matrices.  相似文献   
997.
998.
A number of important problems in computers and telecommunications, such as distributed databases and multipoint multimedia conferencing, all require the solution of a generic problem called multiple destinations routeing (MDR). In this paper, we formulate the MDR problem as a zero-one integer programming problem and propose a technique to reduce the computation required for the optimum solution. Three heuristics are designed for large MDR problems. Heuristic A can offer different degrees of optimality with different amounts of time allowed for the solution. Heuristic B is a modification of Prim's algorithm for the minimum spanning tree. It gives a fairly good solution with very little computation. Heuristic C is based on Heuristic B and is for minimizing the number of edges in the multicast tree (i.e. assuming that all edge weights are the same). It always gives a better solution than Heuristic B. Simulation on two example networks shows that Heuristics A and C always give better solutions (or lower cost connection paths) than the improved RS algorithm, which has up to now been the best heuristic.  相似文献   
999.
The suprascapular nerve supplies sensory nerves to the posterosuperior aspect of the shoulder, including major portions of the rotator cuff. Suprascapular nerve block using steroid/bupivacaine is temporarily effective in reducing pain in rotator cuff tendinitis and tears, improving movement range in tendinitis and is possible in an outpatient setting with little or no complication risk.  相似文献   
1000.
OBJECTIVE: To elucidate whether diminished levels of androgen receptor (AR) are the underlying cause for the development of hypospadias by determining AR levels in the foreskins of boys with hypospadias. PATIENTS AND METHODS: The content of AR was determined by a sensitive immunoblotting technique in extracts from preputial tissue obtained from 15 patients (mean age 2.5, SD +/- 1.5 years) with hypospadias and from seven controls (mean age 2.5, SD +/- 1.5 years). Immunoreactivity of the protein was measured by densitometry. RESULTS: No significant difference in mean AR content was found between those boys with hypospadias (2.1 +/- 0.9 fmol/mg protein, +/- SD) and the age-matched control group (2.2 +/- 0.3 fmol/mg protein). Stratification by the severity of hypospadias (distal and proximal on the shaft, and penoscrotal hypospadias) showed that the severity was not related to tissue AR levels. CONCLUSION: It is unlikely that hypospadias is caused by a decreased expression of AR.  相似文献   
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