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41.
42.
Hepatitis C virus (HCV) infection has been demonstrated to result in several adverse hepatic outcomes and has been associated with a number of important extrahepatic manifestations. The scope of extrahepatic clinical possibilities includes systemic diseases such as vasculitis and lymphoproliferative disorders, cardiovascular disease, myalgia, arthritis, and sicca syndrome. These end‐organ effects of HCV may dominate the clinical course beyond the hepatic complications and significantly worsen the long‐term prognosis of infected patients. Until several years ago, the standard of care for the treatment of HCV infection had been interferon‐alpha‐based regimens, which not only had limited effectiveness in achieving a cure but were often poorly tolerated, especially in patients with kidney disease. In those HCV‐infected patients with significant systemic manifestations, the interferon‐based regimens were problematic given their association with a wide variety of toxicities. The development of highly effective direct‐acting antiviral agents to treat HCV infection presented an opportunity to improve the HCV care cascade with the eradication of HCV in most infected patients and by reducing the burden of both hepatic and extrahepatic complications.  相似文献   
43.
PURPOSE: To demonstrate whether streamlining of the portal vein flow exists by evaluating the relative distribution of blood flowing from the superior mesenteric vein (SMV) and splenic vein (SV) into the portal venous system. MATERIALS AND METHODS: Fifteen healthy adult volunteers underwent MR angiography of the main portal vein (PV) and portal vein branches after an overnight fast. Transverse two dimension time-of-flight gradient echo sequences were obtained three times, in suspended expiration and inspiration, respectively, as follows: 1) No presaturation slab, 2) presaturation slab across the SMV, 3) presaturation slab across the SV. Signal intensity (SI) measurements were obtained for all acquisitions. using regions of interest traced manually within the PV and portal branches. RESULTS: After presaturation of the SMV and SV during expiration, the overall SI average in the PV decreased by 47% +/- 8 (mean +/- SD) and 17% +/- 9, respectively. Right to left portal branch SI ratio and right-anterior to left-posterior SI ratio in the PV were 0.91 +/- 0.09 and 1.02 +/- 0.08 at baseline, respectively. They decreased significantly (P < 0.05) to 0.87 +/- 0.09 and to 0.95 +/- 0.09 after saturation of the SMV, and increased significantly to 0.95 +/- 0.08 and to 1.07 +/- 0.10 after saturation of the SV. CONCLUSION: MR angiography with selective saturation of the SMV and SV provided reproducible assessment of the respective contributions of the SMV and SV to portal flow, and allows demonstration that streamlining of splanchnic blood occurs in the portal vein of normal subjects.  相似文献   
44.

Background

Dual mobility (DM) cups of mobile polyethylene were introduced to prevent total hip arthroplasty (THA) dislocation, but no large series with this design to treat recurrent instability have been reported.

Purpose

Our retrospective investigation ascertained the efficiency of DM cups in correction of recurrent dislocation and assessed any adverse effects.

Methods

One hundred eighty THAs with recurrent instability were revised to DM cups in 180 patients (mean age, 67.4 ± 11.7 years; range, 19 to 92 years). Thirty-one patients (17.2%) underwent at least one earlier THA revision, and 15 (10.3%) incurred non-union of the greater trochanter. Of the initial group in 2009, 145 patients had completed evaluations which included assessment of the Harris Hip Score and a radiographic assessment at a mean follow-up of 7.7 ± 2.2 years (range, 4 to 14 years). The rate of survival was calculated considering any reason for revision as failure.

Results

At follow-up, Harris hip score was 83.9 ± 16.1 (range, 21 to 100). Dislocation of the large articulation occurred in seven hips (4.8%), and only two recurred (1.4%) (one requiring additional revision). In addition, two intra-prosthetic dislocations of the small articulation (1.4%) were observed and needed revision surgery. The large number of earlier surgeries and non-union of the greater trochanter were related to recurrent instability. Two cups (1.4%) showed signs of definite loosening; six (4.1%) presented signs of possible loosening. Twenty-nine hips manifested femoral or acetabular osteolysis (20%), but only three were severe. Eight-year survival rate considering revision for any reason was 92.6% (95% CI, 85.5–96.4%).

Conclusions

This series indicates that DM cups are a viable option to treat recurrent THA instability. Their design provides a low risk of recurrent instability without increasing mechanical complications.  相似文献   
45.
OBJECTIVE: Calcium and vitamin D deficiency is common in older individuals, particularly those who live in nursing homes, and increases the risk of osteoporosis and fractures. METHODS: We conducted a randomized double-blind placebo-controlled study of combined supplementation with 500 mg of elemental calcium, as carbonate, and 400 IU of vitamin D bid for 12 months in women older than 65 years of age with vitamin D deficiency, defined as serum 25(OH)D concentrations 相似文献   
46.
We describe five primary tumors of the adenohypophysis featuring mitochondrion-rich spindle cells. The patient ages ranged from 53 to 71 years (mean 61.6 years); two were female. All presented with panhypopituitarism. Two also had visual field defect. On neuroimaging all tumors showed suprasellar extension and were indistinguishable from pituitary adenoma. None showed imaging or operative evidence of dural involvement. All were gross totally removed: four by transsphenoidal surgery and one by frontal craniotomy. Follow-up ranged from 2 to 68 months (mean 35.4 months). No recurrences were noted. The clinical workup was noncontributory in all but two patients: one (case no. 4) with an oncocytic thyroid adenoma and another (case no. 5) with squamous carcinoma of both the uterine cervix and of vocal cord. Histologically, the five tumors were composed mainly of fascicles of spindle cells with eosinophilic, granular cytoplasm. Mitoses were rare and necrosis was absent. Neoplastic cells were immunoreactive for vimentin, epithelial membrane antigen, S-100 protein, and galectin-3. Stains for pituitary hormones, synaptophysin, chromogranin, glial fibrillary acidic protein, cytokeratin CAM5.2, smooth muscle actin, CD34, and CD68 were negative. No thyroglobulin immunoreactivity was noted in the tumor of case no. 4. Ultrastructurally, the neoplastic cells contained numerous mitochondria with lamellar cristae. The neoplastic cells were linked by intermediate junctions and desmosomes. No secretory granules were noted. The histologic, immunohistochemical, and fine structural features of these tumors were unlike those of pituitary adenoma or any other primary sellar tumor. A derivation from adenohypophyseal folliculostellate cells is suggested.  相似文献   
47.
Tumor thrombus in major vasculature is a frequent finding with a poor long-term prognosis in patients with hepatocellular carcinoma (HCC). The utility of surgical resection is still controversial. This study compared morbidity and survival after resection for HCC with and without tumor thrombus. Data of 108 patients who underwent major hepatic resection for HCC were prospectively recorded. Patients were divided into two groups. The venous thrombectomy (VT) group included 26 patients who had HCC with tumor thrombus in the portal or hepatic veins. The matched control group included 82 patients who had HCC without tumor thrombus. Surgical technique, early outcome, and late survival were analyzed in each group. Multivariate analysis was performed to assess the prognostic value of this feature. Surgical technique was comparable in the VT and control group with regard to extent of hepatectomy, procedure duration, and transfusion requirements. Early postoperative outcome was also comparable. Actuarial survival at 1, 3, and 5 years was 38%, 20%, and 13%, respectively, in the VT group (median: 9 months) versus 74%, 56%, and 33%, respectively, in the control group (median: 41 months). In the subgroup of patients with tumor thrombus limited to the portal vein, actuarial survival at 1, 3, and 5 years was 50%, 26%, and 17%, respectively, (median: 12 months) and two patients lived longer than 5 years. Multivariate analysis showed that incomplete resection, alphafetoprotein level greater than 100 N, more than two tumor nodules, and tumor thrombus in major vasculature were independent factors of poor prognosis. Survival after resection for HCC with tumor thrombus in the major vasculature is poorer than after resection for HCC without tumor thrombus. However, an aggressive surgical strategy can provide significant survival with comparable morbidity in selected cases, that is, tumor thrombus located in the portal vein only and expected complete resection of the lesions.  相似文献   
48.
BACKGROUND: Although numerous methods of postoperative analgesia have been investigated in an attempt to improve pain control after total knee arthroplasty, parenteral narcotics still play a major role in postoperative pain management. Local anesthetics have the advantage of blocking pain conduction at its origin and minimizing the systemic side effects associated with postoperative narcotic use. This study was performed to evaluate the benefits and safety of a multimodal analgesia protocol that included periarticular injection of large doses of local anesthetics in patients undergoing total knee arthroplasty. METHODS: We compared morphine consumption during the first twenty-four hours after unilateral total knee arthroplasty in forty-two patients who had been randomized to receive either (1) a perioperative infiltration mixture, consisting principally of local anesthetic, and self-administered morphine or (2) self-administered morphine only. Narcotics consumption, pain control, medication-related side effects, plasma levels of the local anesthetic (ropivacaine), and postoperative rehabilitation were monitored. RESULTS: Although there was high satisfaction and good pain control in both groups, morphine consumption was significantly lower in the local analgesia group than it was in the control group (28.8 +/- 17.4 mg compared with 50.3 +/- 25.4 mg twenty-four hours after surgery, and 46.7 +/- 19.4 mg compared with 68.6 +/- 38.6 mg forty hours after surgery). Both groups achieved a similar amount of knee flexion on the fifth postoperative day. Over the five-day period after the procedure, the patients in the local analgesia group reported a total of 2.6 +/- 3.9 hours of nausea compared with 7.1 +/- 12.2 hours in the control group. No complications related to the infiltration of the local anesthetic were observed, and all plasma concentrations of the local anesthetic were below the toxic range. CONCLUSIONS: This multimodal perioperative analgesia protocol that included infiltration of a local anesthetic offered improved pain control and minimal side effects to patients undergoing total knee arthroplasty. Our study also confirmed the safety of the protocol.  相似文献   
49.
50.
BACKGROUND: Information about chronic dialysis (CD) patients admitted to intensive care units (ICU) is scant. This study sought to determine the epidemiology and outcome of CD patients in an ICU setting and to test the performance of the Simplified Acute Physiology Score (SAPS II) to predict hospital mortality in this population. METHODS: All consecutive CD patients admitted to an adult, 10 bed medical/surgical ICU at a university hospital between January 1996 and December 1999 were included in this prospective observational study. Demographics, characteristics of the underlying renal disease, admission diagnosis, the number of organ system failures (OSFs) excluding renal failure and SAPS II, both calculated 24 h after admission, the duration of mechanical ventilation, ICU survival and survival status at hospital discharge and 6 months after discharge were recorded. RESULTS: A total of 92 CD patients, 16 on peritoneal dialysis and 76 on haemodialysis, were included. The main reason for ICU admission was sepsis and the mean ICU length of stay 6.2+/-9.9 days. ICU mortality was 26/92 (28.3%) and was associated in multivariate analysis with SAPS II (P<0.001), duration of mechanical ventilation (P<0.01) and abnormal values of serum phosphorus (high or low; P<0.05). Hospital mortality was 35/92 (38.0%) and was accurately predicted by SAPS II [receiver operating characteristics curve: 0.86+/-0.04; goodness-of-fit test: C = 6.86, 5 degrees of freedom (df), P = 0.23 and H = 4.78, 5 df, P = 0.44]. The 6 month survival rate was 48/92 (52.2%). CONCLUSIONS: CD patients admitted to the ICU are a subgroup of patients with high mortality and SAPS II can be used to assess their probability of hospital mortality. The severity of the acute illness responsible for ICU admission and an abnormal value of serum phosphorus are determinants for ICU mortality.  相似文献   
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