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991.
BACKGROUND/AIMS: The prognosis after curative resection for patients with carcinoma of the papilla of Vater is relatively better than that for other peripancreatic cancer. However, prognostic factors after resection of the carcinoma have not been identified. METHODOLOGY: From 1983 to 1999, 16 patients with carcinoma of the papilla of Vater underwent standard pancreatoduodenectomy and dissection of regional lymph nodes. We followed the patients for 63 days to 17 years (median, 27 months) and analyzed clinicopathologic variables in relation to prognosis. RESULTS: The survival rate at 5 years was 50.5%. The morphologic factors predicting poor outcome were macroscopic ulcer formation and microscopic pancreatic, venous, or perineural invasion. Tumors with ulcer formation tended to infiltrate into the duodenum and pancreas, but not into veins or the perineural space. Eight of 16 patients died due to recurrence of the cancer; liver metastasis (n = 6) or peritoneal dissemination (n = 2). CONCLUSIONS: Patients with carcinoma of the papilla of Vater demonstrating ulcer formation or invasion into the pancreas, vein, or perineural space may benefit from adjuvant therapy to reduce the risk of liver metastasis. Careful observation is essential for liver metastasis or peritoneal dissemination after surgery; especially in patients with ulcer formation or venous invasion.  相似文献   
992.
OBJECT: The purpose of this study was to determine whether the preoperative measurement of acetazolamide-induced changes in cerebral blood flow (CBF), which is performed using single-photon emission computerized tomography (SPECT) scanning, can be used to identify patients at risk for hyperperfusion following carotid endarterectomy (CEA). In addition, the authors investigated whether monitoring of CBF with SPECT scanning after CEA can be used to identify patients at risk for hyperperfusion syndrome. METHODS: Cerebral blood flow and cerebrovascular reactivity (CVR) to acetazolamide were measured before CEA in 51 patients with ipsilateral internal carotid artery stenosis (> or = 70% stenosis). Cerebral blood flow was also measured immediately after CEA and on the 3rd postoperative day. Hyperperfusion (an increase in CBF of > or = 100% compared with preoperative values) was observed immediately after CEA in eight of 12 patients with reduced preoperative CVR. Reduced preoperative CVR was the only significant independent predictor of post-CEA hyperperfusion. Forty-three patients in whom hyperperfusion was not detected immediately after CEA did not exhibit hyperperfusion on the 3rd postoperative day and did not experience hyperperfusion syndrome. In two of eight patients in whom hyperperfusion occurred immediately after CEA, CBF progressively increased and hyperperfusion syndrome developed, but intracerebral hemorrhage did not occur. In the remaining six of eight patients in whom hyperperfusion was detected immediately after CEA, the CBF progressively decreased and the hyperperfusion resolved by the 3rd postoperative day. CONCLUSIONS: Preoperative measurement of acetazolamide-induced changes in CBF, which is performed using SPECT scanning, can be used to identify patients at risk for hyperperfusion after CEA. In addition, post-CEA monitoring of CBF performed using SPECT scanning results in the timely and reliable identification of patients at risk for hyperperfusion syndrome.  相似文献   
993.
994.
Ischemia-induced hyperactivity is recognized several hours after both common carotid arteries' occlusion for 5 min in Mongolian gerbils, and it continues for at least 7 days. The aim of this study is to investigate the possible mechanisms of this abnormal behavior. Methamphetamine (MAP) (1 and 3 mg /kg) was administered for 7 days and imipramine (IMP) (5 and 10 mg/kg) was administered for 7 or 14 days. Bilateral carotid artery was occluded for 5 min 24 h after the last administrations of these drugs. MAP, which had been administered every day for 1 week, showed marked inhibition in the ischemia-induced hyperactivity. However, IMP did not have any effect even though it had been injected every day for 2 weeks. Hippocampal CA1 neuronal changes also appeared in the MAP- and IMP-administered groups. As the dopaminergic neurotransmission is facilitated by the repeated administration of MAP, the ischemia-induced hyperactivity may be related to abnormalities in dopaminergic function. The participation of the other neurotransmitters is also discussed.  相似文献   
995.
Direct reaction between shikonin and thiols induces apoptosis in HL60 cells   总被引:1,自引:0,他引:1  
Shikonin (beta-alkannin), a naphthoquinone compound, was found to induce apoptotic features such as chromatin condensation, DNA fragmentation, and activation of caspase 3 in HL60 cells. The mechanism was examined in terms of oxidative stress in the cells. Exposure of the cells to shikonin greatly reduced the total thiols, protein thiols, and glutathione levels, however, lipid peroxide levels were enhanced. The depletion of thiol levels in the cells was thus thought to induce lipid peroxidation and DNA fragmentation. An electron spin resonance study revealed that shikonin reacts directly with glutathione and other oxidative stress-relevant compounds in the lysate of HL60 cells. Pretreatment of such cells with N-acetylcysteine before shikonin treatment completely inhibited the DNA fragmentation. From these results, it was proposed that the chemical reaction between shikonin and cellular thiols such as glutathione and protein thiols induces apoptosis in HL60 cells.  相似文献   
996.
“Adult T-cell leukemia/lymphoma” with bone demineralization   总被引:1,自引:0,他引:1  
Two patients with T-cell malignancy having radiographic manifestations of generalized and localized bone demineralization are reported. One, a 53-year-old man, had marked osteoporosis and severe hypercalcemia, but no clinical evidence of leukemia throughout his illness. At autopsy there was no definite evidence of bone involvement. Histologic proof was obtained from abdominal skin which revealed adult T-cell leukemia/lymphoma (ATLL). The second case, a 33-year-old man, complained of arthralgia in his hands and feet; radiographs showed severe localized demineralization and pathologic fractures. Specimens of his peripheral blood, cervical lymph nodes, and bone marrow revealed ATLL cells.  相似文献   
997.
998.
Objective: To evaluate the safety and efficacy of once weekly albiglutide added to a single oral antidiabetic drug (OAD) in Japanese patients with inadequately controlled type 2 diabetes mellitus (T2DM).

Research design and methods: In this phase 3, 1 year study (NCT01777282), patients (N?=?374) received albiglutide 30?mg plus a single OAD (sulfonylurea [n?=?120], biguanide [n?=?67)], glinide [n?=?65], thiazolidinedione [n?=?61], or α-glucosidase inhibitor [n?=?61]). Albiglutide could be increased to 50?mg after Week 4, based on glycemic criteria. Primary endpoints were the incidence of adverse events (AEs) and hypoglycemia; secondary endpoints were changes from baseline at Week 52 in HbA1c and fasting plasma glucose (FPG), proportion of patients achieving HbA1c ≤7.0%, and withdrawals due to hyperglycemia.

Results: On-therapy AEs occurred in 78.6% of patients and serious AEs in 2.1%. Common AEs were nasopharyngitis (32.6%), constipation (7.2%), and diabetic retinopathy (5.3%). No serious AEs occurred more than once or were reported in >1 patient. Hypoglycemia occurred in 6.4% of patients, mostly in the albiglutide?+?sulfonylurea (14.2%) and the albiglutide?+?glinide (6.2%) groups. Albiglutide was uptitrated in 53.2% of patients. Mean baseline HbA1c was 8.1%. Mean decreases from baseline in HbA1c were observed with the addition of albiglutide to thiazolidinediones (?1.42%), α-glucosidase inhibitors (?1.39%), sulfonylureas (?1.04%), glinides (?0.95%), and biguanides (?0.94%). HbA1c of <7% in >50% of patients and mean reductions in FPG were achieved in all groups. Mean changes from baseline in body weight ranged from +0.52?kg (albiglutide?+?thiazolidinedione) to ?0.33?kg (albiglutide?+?biguanide). Limitations of the study included open label treatment that was not randomized.

Conclusions: When combined with a single OAD in Japanese patients with inadequately controlled T2DM, albiglutide led to favorable changes in all glycemic parameters, with minor changes in body weight depending on the background OAD. No new safety concerns were noted.  相似文献   
999.

Background

Ceramic bearings are not commonly used in total knee arthroplasty (TKA). So far, little information is available about whether long-term survivorship and good clinical outcomes can be ensured with ceramic knee implants. The purposes of the present study were to evaluate the clinical and radiological outcomes, and to assess the long-term durability of a ceramic tri-condylar implant.

Methods

A total of 507 consecutive TKAs were carried out using a ceramic tri-condylar femoral implant. The posterior cruciate ligament was sacrificed, and all components were fixed with bone cement. Clinical outcomes were assessed retrospectively with the Knee Society scoring system. Kaplan-Meier survivorship was calculated to determine the cumulative survival rate.

Results

One hundred sixty-seven knees (114 patients) were available for clinical outcomes. The average range of flexion improved from 118.1° preoperatively to 123.7° at a minimum 15-year follow-up (P < .001). The average Knee Society knee score improved from 39.1 to 92.8 (P < .001). The functional score also improved from 36.0 to 47.0 (P < .001). With revision for any surgery or radiographic failure as the end point, Kaplan-Meier survivorship at 15 years was 94.0%. With revision of any component as the end point, the corresponding survivorship was 96.2%.

Conclusion

Clinically, the postoperative knee flexion range and Knee Society scores were good after long-term follow-up. The survivorship of the ceramic knee implant was excellent over the 15-year follow-up, and long-term durability was achieved, making ceramic a promising alternative material for the femoral component in TKA.  相似文献   
1000.
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