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71.
BACKGROUND: The purpose of this study was to develop a prognostic system applicable to patients with hepatic metastasis from colorectal cancer in whom extrahepatic disease was excluded by preoperative PET with [(18)F]fluoro-2-deoxy-D-glucose (FDG-PET). Data from two institutions were analyzed separately and together to improve general applicability of results. STUDY DESIGN: Data were analyzed for 285 consecutive patients undergoing liver resection for colorectal metastases from 1995 to 2005 at 2 institutions routinely using preoperative FDG-PET with. Fifteen clinicopathologic variables of the primary and secondary tumors were examined to identify factors predictive of survival. RESULTS: Outcomes were correlated with poorly differentiated tumor grade in both data sets. Because patients with poorly differentiated tumors comprised a small proportion (16%) of the population, patients with well-differentiated or moderately differentiated tumors were analyzed independently. In this subgroup, positive lymph node status in the primary colorectal tumor resection specimen was the only characteristic that predicted survival of patients in both institutions. Consequently, patients were sorted into three prognostic categories: poor tumor differentiation; well-differentiated or moderately differentiated tumors and node positive; and well-differentiated or moderately differentiated tumors and node negative. These groups had significantly different overall survival on Kaplan-Meier analysis (p=0.0014). CONCLUSIONS: In patients with colorectal liver metastases staged with FDG-PET with overall survival can be predicted directly from data in the pathology report of the colorectal primary tumor. This study also indicates the need for new molecular tumor markers of prognosis to complement clinicopathologic markers if the goal of prediction of outcomes in individual patients is to be reached.  相似文献   
72.
BACKGROUND: Systemically administered insulin has been shown to accelerate wound healing. To minimize the hypoglycemic and hypokalemic effects of insulin, we investigated a new route of insulin administration by local injection into skin wounds. MATERIALS AND METHODS: Partial thickness skin donor site wounds were created on the backs of adult rabbits with a dermatome set at 0.015 inch. The wounds were covered by Aquaphor gauze (Smith and Nephew, Largo, FL), and OpSite membrane (Smith and Nephew, Hull, United Kingdom) and protected by rabbit jackets. Long-acting insulin-zinc suspension was selected for local injection. In study 1, insulin was injected into the wound at different doses, and the concentrations of blood glucose and wound insulin were measured to determine the proper dose and injection frequency. In study 2, wound healing days were compared between two groups (n = 7 each) receiving local injection of either insulin-zinc or zinc alone as control. Based on the results from study 1, a dose of 0.25 units of long-acting insulin-zinc suspension was injected into the wound every other day in the insulin group. RESULTS: After injection, 0.25 units of insulin decreased blood glucose concentration (minimum 60 mg/dL) during the first 3 h, which then returned to the preinjection level (80 mg/dL). One injection maintained wound insulin concentration above 50 muU/mL for more than 24 h. With local injection of 0.25 units insulin-zinc every other day, the wound healing time was 11.2 +/- 2.3 d, which was faster (P = 0.02) than 15.1 +/- 4.1 d in the control group. CONCLUSION: Local injection of long-acting insulin-zinc suspension accelerated skin wound healing without major systemic side effects, demonstrating its potential usefulness in burn treatment.  相似文献   
73.
Anaesthetists rely upon a loss of resistance and flow of cerebrospinal fluid to indicate when a spinal needle has breached the dura. The loss of resistance is not always felt, with the danger that the needle may be advanced into neurological tissue. One hundred women undergoing elective caesarean section were recruited and spinal anaesthesia, using a 27-G Whitacre needle, was performed using an incremental advancement technique. After each advancement of the needle, and before removing the stylet, it was recorded whether the anaesthetist had perceived any sign that the dura had been breached, and then whether cerebrospinal fluid had been obtained. Six patients were not included in the study due to technical difficulties. In 27 of 94 patients (29%) there was no clear tactile sign that the dura had been breached when cerebrospinal fluid was obtained. This study demonstrates that loss of resistance is not always felt when a 27-G spinal needle breaches the dura in the pregnant woman.  相似文献   
74.
Hepatic artery embolization (HAE) has been utilized for treatment of advanced hepatic carcinoid metastases, with promising symptom palliation and tumor control. Our institution employs transcatheter HAE using Lipiodol/Gelfoam for treatment of carcinoid hepatic metastases, and this report presents our experience with twenty-four patients, examining symptom control, quality-of-life, octreotide dependence, and tumor progression. Twenty-four (11 male, 13 female, mean age = 59.4 ± 2.5 yr) patients with carcinoid and unresectable hepatic metastases, confirmed by urinary 5-hydroxyindole acetic acid (5-HIAA) measurement and biopsy, were treated with Lipiodol/Gelfoam HAE from 1993–2001. Median follow-up was 35.0 months. Before HAE, 14 patients (58.3%) had malignant carcinoid syndrome, with symptoms quantified using our previously reported Carcinoid Symptom Severity Score, and 13 patients (54.2%) required octreotide for symptom palliation. Following treatment, symptom severity, octreotide dose, and tumor response were measured. Asymptomatic patients did not develop symptoms or require following treatment. Hepatic metastases remained stable (n = 4) or decreased (n = 19) in 23 patients (95.8%). Mean pretreatment Symptom Severity Scores (3.8 ± 0.2), decreased to 1.4 ± 0.1 post-treatment (P < 0.00001), with 64.3% of patients becoming asymptomatic. Mean pretreatment octreotide dosages (679.6 ± 73.0 μg/d), decreased to 262.9 ± 92.7 μg/d (P = 0.0024) post-treatment, with 46.2% of patients discontinuing octreotide. There were no treatment-related serious complications or deaths. This study demonstrates that Lipiodol/Gelfoam HAE produces excellent control of malignant carcinoid syndrome, allowing patients to decrease or eliminate use of octreotide, while controlling hepatic tumor burden. Presented at the Forty-First Annual Meeting of The Society of the Alimentary Tract, San Diego, California, May 21–24, 2000 (poster presentation).  相似文献   
75.

Background

Bariatric surgery leads to remission of several obesity-related comorbidities, including hypertension. Although antihypertensive medication use is decreased after bariatric surgery, the exact time course of decrease in blood pressure after surgery is not known.

Methods

A database of patients undergoing bariatric surgery at our institute was used to study the effect of surgery on time course of blood pressure changes. Data from surgeries performed between January 2010 and December 2012 were used.

Results

Maximum blood pressure and body weight decreases were observed at 2 weeks and 1 year after surgery, respectively. Average decrease in the mean arterial pressure (MAP) was 4.46 mmHg (61.5?±?17.1% of maximal decrease) and 7.17 mmHg (maximum decrease) at 1 and 2 weeks after surgery, when the decrease in body weight is 22.8?±?1.6 and 28?±?1.4% of maximal weight loss, respectively. In hypertensive patients, MAP decreased from 98.5?±?0.78 to 92.3?±?1.76 and 93.1?±?0.92 mmHg at 1 and 2 weeks post-surgery, respectively. In normotensive patients, the MAP decreased from 96.2?±?0.79 to 88.7?±?1.25, 90.0?±?0.94, 86.5?±?1.35, 88.0?±?1.13, and 86.4?±?2.13 mmHg at 2 weeks, 3 and 6 months, and 1 and 3 years after surgery, respectively.

Conclusions

These data demonstrate that significant decrease in MAP occurs within 2 weeks after bariatric surgery in hypertensive as well as normotensive patients. Future studies are required to investigate the weight-independent mechanisms of blood pressure decreases after bariatric surgery.
  相似文献   
76.
77.
Carbon dioxide digital subtraction angiography: the practical approach   总被引:1,自引:0,他引:1  
CO(2) has developed into a viable alternative to iodinated contrast for digital vascular imaging. Because CO(2) is a gas, it has a unique set of properties that affords certain advantages over iodinated contrast in a variety of settings. However, if CO(2) is used inappropriately, these same properties are associated with a unique set of rare but potentially harmful events. Therefore, it is essential that these unique characteristics be understood in order to employ a few simple precautionary measures. Fortunately, there is a delivery system currently available that is readily assembled and easy to use that ensures the appropriate administration of CO(2). This system, combined with experience, can reduce the greater labor intensity sometimes associated with CO(2) digital subtraction angiography. When it is used appropriately, CO(2) digital subtraction angiography alone or in combination with iodinated contrast offers diagnostic and interventional rewards that are not available with traditional intravascular contrast examinations.  相似文献   
78.
The purposes of the present study were to determine if recombinant human transforming growth factor-beta-2 (rhTGF-beta2) enhances bone ingrowth into porous-coated implants and bone regeneration in gaps between the implant and surrounding host bone. The implants were placed bilaterally for four weeks in the proximal humeri of skeletally mature, adult male dogs in the presence of a 3-mm gap. In three treatment groups of animals, the test implant was treated with hydroxyapatite/tricalcium phosphate (HA/TCP) and rhTGF-beta2 in buffer at a dose per implant of 1.2 microg (n = 6), 12 microg (n = 7), or 120 microg (n = 7) and placed in the left humerus. In these same animals, an internal control implant treated only with HA/TCP and buffer was placed in the right humerus. In a non-TGF-beta treated external control group of animals (n = 7), one implant was treated with HA/TCP while the contralateral implant was not treated with the ceramic. In vitro analyses showed that approximately 15%, of the applied dose was released within 120 h with most of the release occurring in the first 24 h. The TGF-beta treated implants had significantly more bone ingrowth than the controls with the greatest effect in the 12 microg/implant group (a 2.2-fold increase over the paired internal control (P = 0.004) and a 4-fold increase over the external control (P < 0.001)). The TGF-beta treated implants had significantly more bone formation in the gap than the controls with the greatest effect in the 12 and 120 microg groups (1.8-fold increases over the paired internal controls (P = 0.003 and P = 0.012, respectively) and 2.8-fold increases over the external controls (P < 0.001 and P = 0.001, respectively)). Compared to the external controls, the internal control implants tended to have more bone ingrowth (1.9-fold increase, P = 0.066) and had significantly more bone formation in the gap (1.7-fold increase. P = 0.008). Thus, application of rhTGF-beta2 to a porous-coated implant-stimulated local bone ingrowth and gap healing in a weakly dose-dependent manner and stimulated bone regeneration in the 3-mm gap surrounding the contralateral control implant, a site remote from the local treatment with the growth factor.  相似文献   
79.
Liu KJ  Atten MJ  Lichtor T  Cho MJ  Hawkins D  Panizales E  Busker J  Stone J  Donahue PE 《The American surgeon》2001,67(3):215-9; discussion 219-20
Serum amylase and lipase elevation has been observed in trauma patients and patients with traumatic intracranial bleeding. However, the causes of this elevation have not been clearly elucidated. A further question remains as to whether other intracranial events are associated with such enzyme elevation as well. We retrospectively reviewed 75 patients consecutively admitted to Cook County Hospital Neurosurgical Intensive Care Unit over a 3-month period for trauma, infection, tumor, or other space-occupying lesions with an unstable condition or neurological deficit. Eleven patients (15%) had elevated amylase and lipase levels. The patients were divided into two groups: Group I (n = 64) had normal and Group II (n = 11) had raised amylase and lipase levels [amylase 402 +/- 444 U/L with normal < or = 125 U/L and lipase 474 +/- 313 U/L with normal < or = 55 U/L]. All Group II patients suffered an intracranial event. Twenty-four Group I (38%) and 10 Group II (91%) patients required craniotomy (P < 0.01). No patients had clinical or radiographic evidence of pancreatitis. In summary, intracranial events are associated with serum amylase and lipase elevation probably through centrally activated pathways. Because of the lack of diagnostic value, routine pancreatic enzyme monitoring should not be performed in this patient population.  相似文献   
80.
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