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141.
An 18-year-old male developed C-5 complete tetraplegia following a motor-cycle accident in May 1975. The neuropathic bladder was managed by an indwelling urethral catheter. He developed recurrent episodes of urinary infection with Proteus species. In September 1975, an X-ray of the abdomen revealed small calculi in both the kidneys. In July 1976, he underwent transurethral resection of the bladder neck and division of the external urethral sphincter; subsequently, he was put on a penile sheath drainage. He continued to suffer from repeated episodes of urinary tract infection with Proteus, Providencia, and Pseudomonas species, and he was treated with antibiotics. In 1980, intravenous urography (IVU) showed two large stones in the left kidney with marked caliectasis. The IVU performed in 1984 showed an increase in the size of the calculi in the left kidney which was grossly hydronephrotic. There were clusters of small calculi in the right kidney. The left renal calculi were treated by percutaneous lithotripsy in two sessions. In 1988, an X-ray of the abdomen revealed staghorn calculus in the right kidney and recurrence of stones in the left kidney. The staghorn calculus in the right kidney was treated by percutaneous nephrostolithotomy in two sessions. In 1991, he was admitted with acute urinary infection. IVU showed a stone in the pelviureteric junction with no excretion of contrast in the left kidney. Percutaneous nephrostomy drainage was established followed by left percutaneous nephrostolithotomy. In 1992, he was found to retain large amount of urine in the bladder; subsequently, his mother was taught to perform regular intermittent catheterisations. In 1995, he was admitted with acute urine infection. Abdominal X-ray revealed recurrence of large stones in both kidneys. With multiple sessions of Extracorporeal Shockwave Lithotripsy (ESWL), about 80% clearance was achieved on the left side. Right staghorn renal stone awaits treatment. This case shows that recurrent urinary infection in spinal cord injury patients is a predisposing factor for renal lithiasis. These patients require annual urological evaluation. Urinary tract calculi, if detected, should be dealt with promptly to prevent renal damage due to urinary obstruction and urosepsis. Renal calculi can be treated effectively and safely by ESWL in spinal cord injury patients, thus avoiding the need for an invasive procedure. It is essential to achieve low-pressure, adequate emptying of the urinary bladder in patients with spinal cord injury in order to prevent recurrent urinary infection and its sequelae. Social issues involved in the care of a tetraplegic patient play a vital role in the implementation of ideal medical treatment and need to be addressed promptly to avoid any compromise in the quality of medical care.  相似文献   
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BACKGROUND: In response to the importance of early stage breast carcinoma as a public health concern and to the complexity of the clinical literature devoted to treatment of the disease, the National Institutes of Health has held a series of Consensus Development Conferences on the treatment of early stage breast carcinoma. The authors assessed compliance with standards of care for women treated in two states. METHODS: The authors identified patients diagnosed at 18 randomly selected hospitals (N = 1514) in Massachusetts and at 30 hospitals (N = 1061) in Minnesota. They collected data from medical records, patients, and their surgeons to assess compliance with four indicators of quality of care: radiation therapy after breast-conserving surgery, axillary lymph node dissection, chemotherapy for premenopausal women with positive lymph nodes, and hormonal therapy for postmenopausal women with positive lymph nodes and positive estrogen receptor status. RESULTS: Rates of compliance for 3 of the 4 standards of care were > 80% in both states. Only the rate for hormonal therapy for postmenopausal women was low (< 64%). However, the proportion of these women who received either chemotherapy or hormonal therapy was > 90% in both states. CONCLUSIONS: In the states studied, practice appears to be consistent with the results of national consensus conferences and clinical trials regarding the treatment of early stage breast carcinoma. For practices demonstrated to be associated definitively with better outcomes (for example, chemotherapy for premenopausal women with positive lymph nodes) or to be important with respect to prognosis (axillary lymph node dissection) high rates of compliance were observed.  相似文献   
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Pneumonia due to Mycoplasma pneumoniae may present at any age after age five. The clinical picture varies from an acute febrile illness to a prolonged disease with affected general state and little pulmonary involvement. The radiological picture is varied but the alveolar pattern predominates, making the differential diagnosis with the bacterial pneumonias difficult. However, in the presence of an interstitial or mixed pattern, especially if generalized, pneumonia due to Mycoplasma pneumoniae must be suspected. This radiological picture is particularly frequent in elderly patients, often affected by other diseases able to induce immunodepression. In such patients the radiology and the unspecific clinical picture frequently cause diagnostic delays. The presence of a pneumonia with multisystem involvement (blood, nervous system, joints, etc.) should suggest the possibility of Mycoplasma pneumoniae infection.  相似文献   
146.
SDZ RAD [40-O-(2-hydroxyethyl)rapamycin] is a macrolide immunosuppressant that is currently under clinical investigation after organ transplantation. The elucidation of its metabolic pathway is essential to improve the understanding of its therapeutic potentials and safety. In this article we describe investigations on the structural identification of some major metabolites of the drug produced by human liver microsomes in vitro. The principles described may be generally applicable for the structural elucidation of complex compound mixtures in biological matrices. Under the conditions of electron impact ionization, SDZ RAD undergoes extensive fragmentation and no information sufficient for structural elucidation is obtained. Therefore, mass spectrometry based on soft electrospray ionization (ESI) in conjunction with collision-induced fragmentation was the method of choice. High-performance liquid chromatography coupled to an ESI mass spectrometer resulted in separation and identification of 16-O-demethyl-SDZ RAD, the ring-opened form of SDZ RAD, and its dehydrate. Additionally, we characterized several demethylated and hydroxylated metabolites.  相似文献   
147.
Squamous carcinoma of the esophagus is a disease with a poor prognosis which fortunately occurs seldom in the United States. Because patients present with more advanced disease here, surgical therapy has not equaled results reported from Asia. Although, claims of equality have appeared in the literature, radiation therapy alone has not been very effective for this disease. There are a myriad of small reports which extol a variety of combined approaches. Based upon a review of these series it is obvious that a Phase III trial is required to establish the best multimodality therapy for management of squamous carcinoma of the esophagus. Components of such a trial are reviewed and suggestions are made for design and reporting of such a trial.  相似文献   
148.
AC machines supplied in parallel by a common voltage source inverter are sometimes used in industrial drives and railway traction applications. This reduction of power and control electronics leads to a reduction of cost, weight, and dimensions that is very useful for on-board systems. But this common supply imposes common voltages to all machines and the possibilities of independent behavior are reduced. In this paper, a graphical modeling is suggested to model such parallel drives for a railway application. A weighted control is then systematically deduced from this modeling and different possibilities of control are highlighted. Experimental results are provided to compare two of the deduced controls  相似文献   
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In this paper we present a methodology for extracting information about lexical translation equivalences from the machine readable versions of conventional dictionaries (MRDs), and describe a series of experiments on semi-automatic construction of a linked multilinguallexical knowledge base for English, Dutch, and Spanish. We discuss the advantages and limitations of using MRDs that this has revealed, and some strategies we have developed to cover gaps where no direct translation can be found.  相似文献   
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