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51.
52.
Thymectomy by partial sternotomy for the treatment of myasthenia gravis   总被引:5,自引:0,他引:5  
BACKGROUND: Myasthenia gravis is an autoimmune disease characterized by weakness and fatigue of voluntary muscles. Surgical treatment of choice for myasthenia gravis has been thymectomy. However, thymectomy indications and surgical approach are still controversial. The purpose of this study is to evaluate the efficacy of partial median sternotomy approach to the thymus. METHODS: From 1973 to 1999, 478 patients with myasthenia gravis underwent thymectomy through a partial median sternotomy. RESULTS: Sixty-one patients (12.7%) had complete remission of symptoms, 299 (62.5%) had a significant improvement, and 83 (17.4%), a mild improvement; whereas 35 patients (7.4%) had no improvement of clinical symptoms. CONCLUSIONS: Partial median sternotomy has shown to be a useful surgical approach to the thymus, as demonstrated by the good functional and aesthetic results, associated with low morbidity and no mortality.  相似文献   
53.

Background

The relationship between C-reactive protein (CRP), nitric oxide (NO), leptin, adiponectin, and insulin growth factor 1 (IGF-1) is poorly defined in morbidly obese patients before and after gastric bypass and, in some cases, is controversial.

Methods

We examined the plasma of 34 morbidly obese patients before and 1, 6, and 12 months after Roux-en-Y gastric bypass surgery.

Results

Obese people had more CRP (21.3?±?1.8 μg/ml) and leptin (36.9?±?4.0 ng/ml) than those in the control group (nonobese people: CRP?= 6.9?±?0.9 μg/ml, p?<?0.0001; leptin?= 7.5?±?0.4 ng/ml, p?<?0.0001). However, they had less NO (30.4?±?2.7 nmol/ml), IGF-1 (77.5?±?6.6 ng/ml), and adiponectin (11.1?±?1.0 μg/ml) than those in the control group (NO?= 45.8?±?3.9 nmol/ml, p?=?0.0059; IGF-1?= 202.0?±?12.0 ng/ml, p?<?0.0001; adiponectin?= 18.0?±?2.0 μg/ml, p?<?0.0001). During weight loss, the amount of CRP and leptin decreased until they reached the nonobese values, but the level of NO remained lower than in nonobese people, even 1 year after surgery. The linear regression slopes were negative and very significant for leptin (p?=?0.0005) and CRP (p?=?0.0018) but were less significant for NO (p?=?0.0221). IGF-1 displayed a very good linear regression (both negative and significant) with some anthropometric parameters, including body mass index (p?=?0.0025), total fat (p?=?0.0177), and the percentage of fat (p?<?0.0001).

Conclusion

For the first time, we report the relationship between IGF-1 and CRP, NO, leptin, and adiponectin. For all these parameters, the best and most widely demonstrated improvements in comorbidities before and during weight loss in morbid obesity were associated with CRP and leptin.  相似文献   
54.
We investigated the expression of nitric oxide synthase (NOS) isoforms -1, -2 and -3 in the retina and optic nerve head (ONH) in an experimental rat model of elevated intraocular pressure (IOP) before and after treatment with timolol, to assess whether its neuroprotective action is associated with the activity of these enzymes. Episcleral vein cauterization in unilateral eyes of Wistar rats was performed to produce elevated IOP. Histological sections of retina and ONH from animals with normal IOP, with elevated IOP, and elevated IOP treated with timolol, were studied by immunohistochemistry with antibodies to NOS-1, NOS-2, and NOS-3. In the control rats, NOS-1 was localized to photoreceptor inner segments, amacrine cells and bipolar cells in the retina, and in astrocytes, pericytes and vascular nitrergic terminals in the ONH. NOS-3 immunostaining localized to the endothelial cells. The rats with elevated IOP showed increased expression of NOS-1 in the plexiform layers of the retina and reactive astrocytes in the ONH. These cells also showed NOS-2 positivity. The rats treated with timolol showed reduced expression of NOS-1 in the retina and ONH. NOS-2 was only detected in a few groups of astrocytes in the ONH. NOS-3 was unchanged in both elevated IOP and timolol-treated groups. These results show that excessive levels of NO synthesized by the NOS-1 and -2 isoforms, considered neurotoxic, might contribute to the progressive lesions of retinal ganglion cell axons. Their reduction after treatment suggests a possible neuroprotective effect of timolol in neurons exposed to excessive amounts of NO.  相似文献   
55.
目的 报告成功实施腹腔镜迷你胃旁路术治疗单纯性肥胖并2型糖尿病病人1例。方法 第二军医大学附属长海医院微创外科于2007年11月对1例伴有2型糖尿病的单纯性肥胖症病人行腹腔镜迷你胃旁路术。结果 病人手术顺利,手术时间135min,术中出血20mL。术后30d内无手术并发症,随访30d,体重下降15kg,体重指数(BMI)减少4.9。术后第8天停用一切降糖药物,各项糖尿病检查指标均正常。结论 腹腔镜迷你胃旁路术是相对安全、简单的术式,近期减重效果良好,对2型糖尿病具有很好的治疗效果。  相似文献   
56.
The ability to recognize multicentric breast cancer preoperatively would assist in identifying appropriate candidates for breast conservation surgery. Tc-99m scintimammography (SMM) is an adjunct to conventional mammography in identifying selected patients with breast cancer. The purpose of this study is to report the utility of SMM in identifying patients with multicentric breast cancer. Breast cancer patients treated by mastectomy who underwent a preoperative SMM between 1992 and 1999 were identified using the institution's Tumor Registry. The pathology report of each patient was reviewed for multicentric disease defined as an additional focus of cancer within a different quadrant of the breast or greater than 2.5 cm from the dominant tumor mass. Each patient's preoperative SMM was reviewed and compared with the pathologic findings to obtain correlative data. Fifty-eight women treated by mastectomy had preoperative SMM (age range 35-78 years; median 52 years). Pathology revealed infiltrating ductal carcinoma in 49 patients (84.5%), infiltrating lobular carcinoma in five patients (8.6%), ductal carcinoma in situ in three patients (5.1%), and colloid carcinoma in one patient (1.7%). Multicentric disease was present in the specimens of eight patients for a prevalence of 10.3 per cent. SMM was positive for uptake in 36 of 58 patients (sensitivity 62.1%). The sensitivity, specificity, positive predictive value, and negative predictive value of SMM in the detection of multicentric disease were 62.5, 96, 71, and 94 per cent, respectively. Although the overall sensitivity of SMM in the detection of breast cancer is superior to that of conventional mammography and physical examination in identifying multicentric breast cancer it is not an accurate modality for detecting multicentric disease in this study group. However, it may have limited applications in specific cases.  相似文献   
57.
BACKGROUND: Isoniazid (INH) therapy for tuberculosis carries a known risk for hepatoxicity, and leads to hepatic failure in a small subset of patients. This incidence has been described for adults, but is uncertain in children. Our aim was to estimate the incidence of pediatric referrals for INH-related liver failure, and to describe the characteristics and outcomes of these patients. METHODS: The 84 U.S. centers performing pediatric liver transplants between 1987 and 1997 were surveyed regarding patients with INH-induced liver failure. Additional transplant statistics were obtained from the United Network for Organ Sharing. Estimates of the number of children taking preventive INH were derived from a nationwide public health database. RESULTS: Twenty cases of INH-related liver failure were found during a 10-year period. Four patients (20%) recovered spontaneously; 10 (50%) underwent orthotopic liver transplantation (OLT), while six (30%) died awaiting OLT. Mean age at presentation was 9.8 years (range 1.3-17). Mean length of INH therapy was 3.3 months (range 0.5-9). Notably, five patients seen for symptoms of hepatitis were initially told not to stop treatment. INH-associated liver failure accounted for 0.2% (8 of 4679) of all pediatric OLTs, and 14% (8/56) of transplants for drug hepatoxicity. The estimated incidence of liver failure was up to 3.2/100,000 for children on prophylactic INH. CONCLUSIONS: While INH-associated liver failure in children is rare, discontinuation at the onset of symptoms does not assure recovery. This indicates a need for increased awareness of hepatotoxicity risk, expanded biochemical monitoring for children receiving INH, and prompt withdrawal in symptomatic patients.  相似文献   
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59.
Recently, there has been considerable interest and debate over the application of minimally invasive surgical approaches to primary total hip arthroplasty. The 2-incision technique employs intermuscular and internervous planes to gain access to the hip joint while minimizing the disruption of muscles and tendons. Through the anterior incision, the femoral neck is osteotomized and the head removed, followed by preparation and cementless reconstruction of the acetabulum. The posterior incision permits femoral preparation and reconstruction with a cementless stem. The potential benefits of this technique include decreased perioperative blood loss and pain, more rapid recovery of hip function and return to normal activity, a reduced length of hospital stay, and cosmetically appealing small scars. Other essential considerations include appropriate patient selection, adherence to surgical principles, and familiarity with specialized instruments and implants.  相似文献   
60.
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