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101.
Safety and efficacy of a new dihydropyridine calcium antagonist, nisoldipine, were studied in 15 patients with proved coronary artery disease and positive exercise treadmill tests. After withdrawal of current therapy and a 2-week placebo phase, patients were given nisoldipine 10, 20, and 40 mg daily (divided into two daily doses), each dose for a 2-week period. Exercise treadmill testing was performed twice during the placebo and once at the end of each nisoldipine phase. Maximal duration of exercise increased with all doses of nisoldipine. Time to 1 mm ST segment depression also increased with all doses of nisoldipine. Peak time to angina was similarly prolonged. Peak exercise double product (heart rate X systolic blood pressure) was unaffected by all doses of nisoldipine. Angina frequency and nitroglycerin consumption decreased during nisoldipine therapy in all patients. Side effects from therapy were only minor. Twice daily therapy compared to three to four times daily therapy with other calcium blockers is an advantage of nisoldipine.  相似文献   
102.
The uncompetitive NMDA receptor antagonist ketamine has been proposed to model symptoms of psychosis. Smooth pursuit eye movements (SPEM) are an established biomarker of schizophrenia. SPEM performance has been shown to be impaired in the schizophrenia spectrum and during ketamine administration in healthy volunteers. However, the neural mechanisms mediating SPEM impairments during ketamine administration are unknown. In a counter‐balanced, placebo‐controlled, double‐blind, within‐subjects design, 27 healthy participants received intravenous racemic ketamine (100 ng/mL target plasma concentration) on one of two assessment days and placebo (intravenous saline) on the other. Participants performed a block‐design SPEM task during functional magnetic resonance imaging (fMRI) at 3 Tesla field strength. Self‐ratings of psychosis‐like experiences were obtained using the Psychotomimetic States Inventory (PSI). Ketamine administration induced psychosis‐like symptoms, during ketamine infusion, participants showed increased ratings on the PSI dimensions cognitive disorganization, delusional thinking, perceptual distortion and mania. Ketamine led to robust deficits in SPEM performance, which were accompanied by reduced blood oxygen level dependent (BOLD) signal in the SPEM network including primary visual cortex, area V5 and the right frontal eye field (FEF), compared to placebo. A measure of connectivity with V5 and FEF as seed regions, however, was not significantly affected by ketamine. These results are similar to the deviations found in schizophrenia patients. Our findings support the role of glutamate dysfunction in impaired smooth pursuit performance and the use of ketamine as a pharmacological model of psychosis, especially when combined with oculomotor biomarkers. Hum Brain Mapp 37:4047–4060, 2016. © 2016 Wiley Periodicals, Inc .  相似文献   
103.
Although he never performed a pituitary operation for the disease, Harvey Cushing was the first to describe and treat patients with Cushing disease (CD). Other surgeons at the time were reluctant to operate on the pituitary due to the normal sella on skull radiographs in CD and the unclear etiology of the disorder. To better define and understand factors influencing the history of pituitary surgery for CD, the authors analyzed historical texts related to CD biology, diagnosis, and treatment. Cushing's monograph on basophilic pituitary adenomas and cortisol excess appeared in 1932. One year later in 1933, Alfred Pattison performed the first successful pituitary operation for CD by implanting radon seeds in the sella. Resection of a pituitary adenoma for CD was attempted 1 month later in 1933 by Howard Naffziger, resulting in only transient improvement that corresponded to the lack of tumor in the resected tissue. Soon thereafter, Susman in 1935 and Costello in 1936 described pituitary basophilic adenomas at autopsy in patients without premorbid endocrinopathy. They concluded that the adrenal gland was the cause of CD, which resulted in a 3-decade abandonment of pituitary surgery for CD. Jules Hardy in 1963 used the operating microscope to perform the first selective removal of an adrenocorticotropic hormone (ACTH)-secreting microadenoma, which established a pituitary cause and defined the modern treatment of CD. Subsequent reports by Hardy, Laws, and Wilson resulted in widespread acceptance of pituitary surgery for CD. Initial reluctance to operate on the pituitary for CD was multifaceted and included general uncertainty surrounding the etiology of Cushing syndrome as well as a lack of early surgical success, both due to the small size of ACTH-secreting adenomas. Selective removal of ACTH-secreting adenomas identified the source of CD and ended the delay in acceptance of pituitary surgery for CD.  相似文献   
104.
Mehta A  Baker TA  Shoup M  Brownson K  Amde S  Doren E  Shah S  Kuo P  Angelats J 《American journal of surgery》2012,203(3):303-6; discussion 306-7
BackgroundSurgical therapy for advanced-stage pressure ulcers recalcitrant to healing is a widely accepted practice. The present study examined the incidence of wound recurrence after reconstruction with fasciocutaneous versus combined (biplanar) muscle and fasciocutaneous flaps.MethodsA retrospective review identified 90 nonambulatory patients with spinal cord injury who underwent reconstruction for persistent decubitus ulcers from 2002 to 2008. Electronic medical records were surveyed for patient comorbidities and postoperative complications. Statistical methods included the Fisher exact test and the Mann–Whitney U test with a 2-sided P value of less than .05.ResultsAmong 90 patients reviewed, 33% (n = 30) received fasciocutaneous flaps and 66% (n = 60) underwent biplanar reconstruction. Comorbidities were the same between cohorts with the exception of a greater prevalence of diabetes in the biplanar group (27% vs 50%; P < .05). The incidence of recurrence for biplanar flaps (25%) was significantly lower than for fasciocutaneous reconstruction (53%; P < .01).ConclusionsBiplanar flap reconstruction should be considered for chronically immobilized patients at high risk for recurrent decubitus ulceration.  相似文献   
105.

Introduction  

Several factors, including race, age, stage, comorbid conditions, social support, and socioeconomic status, have been linked to the likelihood of a patient having surgery for early-stage non-small cell lung cancer (NSCLC). The aim of the present study is to determine the influence of race and health disparities on refusal of recommended potentially curative surgery.  相似文献   
106.
Imatinib mesylate has become the treatment of choice for gastrointestinal stromal tumors (GISTs) and has made a revolutionary impact on survival rates. Bone marrow necrosis is a very rare adverse event in malignant GIST. Bone metastases are also rarely encountered in the setting of this disease. The authors report on a patient with malignant GIST who developed a bone lesion, mimicking spinal metastasis on both MR imaging and FDG-PET/CT. Corpectomy and anterior fusion was performed, but the pathology report was consistent with bone marrow necrosis. Radiological and clinical similarities made the distinction between metastasis and bone marrow necrosis challenging for the treating physicians. Instead of radical surgical excision, more conservative methods such as percutaneous or endoscopic bone biopsies may be more useful for pathological confirmation, even though investigations such as MR imaging and FDG-PET/CT indicate metastatic disease.  相似文献   
107.
OBJECTIVE: Patients with end-stage renal failure and upper-extremity arterial occlusive disease sometimes have painful digital ulceration. We evaluated the efficacy of distal bypass grafting from the brachial artery for limb salvage in this setting. METHODS: All patients with end-stage renal disease with painful digital ulceration or gangrene of the hand seen from 1992 to 2002 were evaluated with clinical examination and noninvasive studies. Those with evidence of occlusive disease underwent conventional angiography. Individuals with forearm occlusive disease underwent bypass grafting, from the brachial artery to either the distal radial artery or ulnar artery at the level of the wrist or proximal hand. Follow-up was scheduled at regular intervals, and included duplex scanning. Limb salvage and bypass graft patency were determined with life table analysis. RESULTS: Over 10 years, 18 forearm bypass procedures were performed in 15 patients. The outflow artery was the radial artery in 15 procedures and the ulnar artery in 3 procedures. Bypass conduit was autogenous in all patients. No patient had a functioning arteriovenous fistula at bypass grafting; six limbs had previously occluded fistulas. Two bypass grafts (11%) occluded in the early postoperative period, with resultant progression of gangrene. In the remaining 16 grafts patency was maintained (mean follow-up, 18 months), with pain control and tissue healing. CONCLUSION: Treatment in patients with renal failure with upper extremity occlusive disease may be facilitated with brachiodistal bypass grafting. Pain control and reversal of progression of hand necrosis can be achieved.  相似文献   
108.
PURPOSE: We measured the impact brachytherapy monotherapy (BMT) has on general and disease specific health related quality of life (HRQOL) compared to patients treated with radical prostatectomy (RP). MATERIALS AND METHODS: We studied 419 men with newly diagnosed prostate cancer who enrolled in CaPSURE (Cancer of the Prostate Strategic Urological Research Endeavor) data base whose primary treatment was brachytherapy monotherapy (92) or radical prostatectomy (327). The validated RAND 36-Item Health Survey and the UCLA Prostate Cancer Index were used to measure HRQOL before treatment and at 6-month intervals during the first 2 years after treatment. RESULTS: Patients treated with BMT or RP did not differ greatly in general HRQOL after treatment. Both treatment groups showed early functional impairment in most general domains with scores returning to or approaching baseline in most domains 18 to 24 months after treatment. Patients treated with BMT had significantly higher urinary function scores at 0 to 6 months after treatment (84.5, SD 18.7) than patients treated with RP (63.3, SD 26.6). Urinary bother scores at 0 to 6 months after treatment were not significantly different between patients treated with BMT (67.7, SD 31.2) and those treated with RP (67.4, SD 29.1). Both treatment groups had decreases in sexual function that did not return to pretreatment levels. CONCLUSIONS: Overall BMT and RP are well tolerated procedures that cause mild changes in general HRQOL. Disease specific HRQOL patterns are different in patients treated with BMT or RP. Baseline and serial HRQOL measurements after treatment can provide valuable information regarding expected quality of life outcome after treatment for localized prostate cancer.  相似文献   
109.
OBJECTIVE: Women undergoing coronary artery bypass grafting (CABG) have higher mortality and morbidity in numerous studies. Although controversial, similar results have been seen in women undergoing carotid endarterectomy. We examined the results of combined eversion CEA/CABG by one group to analyze if the outcome is different between men and women in this setting. METHOD: The records of all patients undergoing combined eversion CEA/CABG were reviewed from our vascular registry between January 1992 and January 2001. Indications, demographics, morbidity, and mortality were retrieved. These results were compared on the basis of gender as well as to patients undergoing CEA alone. Significance was assessed using Theta(2) analysis. RESULTS: There were 563 combined eversion CEA/CABG procedures performed over the 9-year study period: 324 in men and 239 in women. Asymptomatic >70% stenosis was seen in 275 (85%) male patients and 215 (90%) female patients (P = not significant [NS]). Stroke was found in four men vs three women (1.2% vs 1.3%, P = NS), whereas death occurred in 13 men and five women (4.0% vs 2.1%, P = NS). Thirty-day stroke/mortality was 4.9% in men vs 3.3% in women (P = NS). During the same period, patients undergoing CEA alone were subject to a stroke-mortality rate of 1.6% in men and 1.2% in women (P = NS). CONCLUSION: This series demonstrated no difference in outcome among patients undergoing combined eversion CEA/CABG procedures on the basis of gender. Although the results demonstrate a significantly higher mortality and morbidity in patients undergoing combined procedures when compared to carotid surgery alone, the combined procedures can be performed safely in both genders. The large number of asymptomatic patients in both the combined and solo procedures may have positively influenced these results.  相似文献   
110.
The purpose of the current study was to compare retrospectively the results of the Insall-Burstein constrained condylar knee implant used with and without intramedullary stems in 207 revision knee arthroplasties with the Insall-Burstein constrained condylar knee implant. One hundred sixty-one knees had either one or two stems placed. One hundred eight femoral stems and 76 tibial stems were placed. Fifty-five knees had no femoral or tibial stem. The average knee scores ranged from 52 preoperatively to 86 postoperatively. The average range of motion postoperatively was 4 degrees (range, 0 degrees -10 degrees ) to 106 degrees (range, 94 degrees -118 degrees ) in this group. The average postoperative knee score was 86 in the unstemmed group and 85 in the stemmed group with no difference in average range of motion. There were four (3%) cases of tibial loosening and two (2%) cases of femoral loosening in the unstemmed group. There were two (2%) cases of tibial loosening and two (2%) cases of femoral loosening at an average followup of 4.2 years (range, 2-6.2 years). Despite the higher constraint inherently designed in an Insall-Burstein constrained condylar knee component, the current study did not show a significantly higher loosening in implants without stems compared with implants used with stems. Therefore, the use of a semiconstrained component does not alone constitute a requirement for the use of an intramedullary stem.  相似文献   
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