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81.
The Trellis Peripheral Infusion System is an over-the-wire 0.035 guidewire compatible device, designed to isolate a region of the peripheral vasculature to allow for lytic drug infusion and dispersion. We used it successfully through a percutaneous approach in two cases of acute thrombosis of a native lower limb artery. The total amount of rt-PA used was 12 and 9 mg, respectively and was delivered through bolus injections obviating the need for a supplementary continuous infusion of the agent. The time for dissolution of thrombus was 45 and 35 minutes, respectively. No complications were observed.  相似文献   
82.
Experimental and clinical data suggest that stents eluting antiproliferative agents can be used for the prevention of in-stent restenosis. Here we investigate in vitro the antiproliferative and apoptotic effect of D-24851 and evaluate the safety and efficacy of D-24851-eluting polymer-coated stents in a rabbit restenosis model (n = 53). Uncoated stents (n = 6), poly (dl-lactide-co-glycolide) (PLGA)-coated stents (n = 7), and PLGA-coated stents loaded with 0.08 ± 0.0025 μM (31 ± 1 μg; low dose; n = 7), 0.55 ± 0.02 μM (216 ± 8 μg; high dose; n = 6), and 4.55 ± 0.1 μM (1774 ± 39 μg; extreme dose; n = 5) of D-24851 were randomly implanted in New Zealand rabbit right iliac arteries and the animals were sacrificed after 28 days for histomorphometric analysis. For the assessment of endothelial regrowth in 90 days, 12 rabbits were subjected to PLGA-coated (n = 3), low-dose (n = 3), high-dose (n = 3), and extreme-dose (n = 3) stent implantation. In vitro studies revealed that D-24851 exerts its growth inhibitory effects via inhibition of proliferation and induction of apoptosis without increasing the expression of heat shock protein-70, a cytoprotective and antiapoptotic protein. Treatment with low-dose D-24851 stents was associated with a significant reduction in neointimal area and percentage stenosis only compared with bare metal stents (38% [P = 0.029] and 35% [P = 0.003] reduction, respectively). Suboptimal healing, however, was observed in all groups of D-24851-loaded stents in 90 days in comparison with PLGA-coated stents. We conclude that low-dose D-24851-eluting polymer-coated stents significantly inhibit neointimal hyperplasia at 28 days through inhibition of proliferation and enhancement of apoptosis. In view of the suboptimal re-endothelialization, longer-term studies are needed in order to establish whether the inhibition of intimal growth is maintained.  相似文献   
83.
OBJECTIVE: The purpose of this study was to determine the diagnostic accuracy of using the retromandibular vein as seen on cross-sectional imaging to help differentiate superficial lobe from deep lobe tumors. METHODS: Of the patients who had parotid neoplasms between January 1997 and July 2002, we were able to identify 44 patients with preoperative imaging studies that were available for evaluation. The films were reviewed by a single head and neck radiologist to determine whether the neoplasms involved the superficial, deep, or both lobes of the parotid gland (total). The lateral margin of the retromandibular vein was used as a marker for the facial nerve, since the nerve is not always visible on CT and MRI scans. The radiologist's findings were then compared with the findings during surgery. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of predicting the location of neoplasms were then calculated. RESULTS: For lesions in the superficial lobe, cross-sectional imaging was able to predict the location of the neoplasm with a sensitivity of 0.91 (95% CI, 0.70-0.98), specificity of 0.86 (95% CI, 0.63-0.96), PPV of 0.88 (95% CI, 0.67-0.97), and NPV of 0.90 (95% CI, 0.67-0.98). For lesions in both lobes (total), cross-sectional imaging was able to predict the location of the neoplasm with a sensitivity of 0.94 (95% CI, 0.68-0.99), specificity of 0.89 (95% CI, 0.71-0.97), PPV of 0.83 (95% CI, 0.58-0.96), and NPV of 0.96 (95% CI, 0.78-0.99). CONCLUSION: Use of the retromandibular vein as a marker for the facial nerve is a sensitive method for identifying the location of parotid gland neoplasms on cross-sectional imaging. This supports the accuracy of using preoperative imaging to detect the position of parotid neoplasms with respect to the facial nerve.  相似文献   
84.
Management of gallstone ileus   总被引:4,自引:0,他引:4  
Background/Purpose. Gallstone ileus is an uncommon complication of cholelithiasis in the elderly with a high morbidity and mortality rate. This study aims to clarify the current surgical management. Methods/results. In a retrospective survey over the past 11 years there were 9 patients with gallstone ileus, all elderly (mean age, 77 years), among 2242 cholecystectomies (0.4%) and 243 operated small intestinal obstructions (3.7%). Urgent laparotomy confirmed gallstone obstruction and a cholecystoduodenal (89%) or cholecystocolonic (11%) fistula. The operation included enterolithotomy alone (3 high-risk cases) or plus fistula repair and cholecystectomy (6 cases). There were 3 postoperative complications including wound dehiscence, wound infection, and obstructive jaundice (morbidity, 37.5%) and 1 death due to myocardial infarction (mortality, 11%). On follow-up (mean, 5 years), 6 patients with cholecystectomy (in 1 case it was performed 2 months after the initial operation) and 1 patient with enterolithotomy alone are well; there was 1 death from an unrelated cause after 1 year. Conclusion. It seems that a one-stage procedure (enterolithotomy plus fistula repair and cholecystectomy), when feasible, should be the first choice. Enterolithotomy alone should be reserved for only unstable and difficult cases.  相似文献   
85.
AIM: To investigate whether smoking is associated with human papilloma virus (HPV) infection. METHODS: HPV infection is considered to be a necessary condition for cervical cancer development. The study population included 1291 women, aged 25-55 years, attending cervical cancer screening. All women had a Papanicolaou (Pap) test, with liquid-based cytology (Thinprep®), an HPV-DNA test and an evaluation of smoking habits. The COBAS® 4800 system was used for HPV-DNA testing, enabling identification of the following high-risk HPV (hrHPV)-types: each of HPVs 16 and 18 separately, and HPVs 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66 and 68 as a cocktail. The evaluation of smoking habits was assessed using the smoking intensity index (SII), a variable formed as the product of cigarettes consumed per day by the days (years × 365) that a woman was a smoker, divided by 1000. RESULTS: There were 136 smokers among 238 women tested positive for hrHPV-types (HPVs 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66 and/or 68), and 463 smokers among 1053 hrHPV-negative women (OR = 1.7, P < 0.001). This association was attributed to the youngest age group of women, aged 25-34 years (OR = 2.3, P < 0.001), while there was no association in other age groups. The intensity of smoking (increasing SII) showed no statistically significant association with hrHPV infection. Cervical infection with HPV 16 and/or HPV 18 was also not associated with age or smoking habits. Finally, no association was found between Pap test status and smoking habits or smoking intensity. CONCLUSION: Smoking appears to be associated with hrHPV infection of the uterine cervix, particularly in younger women. Further studies should investigate whether this association is based on causality and evaluate the role of other possible co-factors.  相似文献   
86.
The impact of the duration of delayed graft function (DGF) on graft survival is poorly characterized in controlled donation after circulatory death (DCD) donor kidney transplantation. A retrospective analysis was performed on 225 DCD donor kidney transplants between 2011 and 2016. When patients with primary nonfunction were excluded (n = 9), 141 recipients (65%) had DGF, with median (IQR) duration of dialysis dependency of 6 (2–11.75) days. Longer duration of dialysis dependency was associated with lower estimated glomerular filtration rate at 1 year, and a higher rate of acute rejection. On Kaplan–Meier analysis, the presence of DGF was associated with lower graft survival (log‐rank test P = 0.034), though duration of DGF was not (P = 0.723). However, multivariable Cox regression analysis found that only acute rejection was independently associated with lower graft survival [HR (95% CI) 4.302 (1.617–11.450); P = 0.003], whereas the presence of DGF and DGF duration were not. In controlled DCD kidney transplantation, DGF duration itself may not be independently associated with graft survival; rather, it may be that acute rejection associated with prolonged DGF is the poor prognostic factor.  相似文献   
87.
Few data are available in the literature regarding fat embolism in cases of bilateral femoral and pathological femoral fractures. The incidence of bilateral femoral fractures ranges from 2-9.5% of the total number of patients with femoral fractures, and they usually occur in high energy trauma and multi-trauma patients. Although injury severity scores tend to underestimate the severity of these injuries, fat embolism seems to occur in increased frequency ranging from 4.8-7.5%. Intramedullary nailing, which is the preferred surgical treatment, triggers a systemic inflammatory response that poses an additional burden to pulmonary function. In addition, the femur is a common site of metastatic bone disease. The treatment of impending and actual pathological fractures is complicated by increased rates of lung damage due to various factors. Fat embolism during treatment--mainly with intramedullary nails--generally seems to range from 0-10%.  相似文献   
88.

Background

Tracking of post-registration head motion is one of the major problems in frameless stereotaxy. Various attempts in detecting and compensating for this phenomenon rely on a fixed reference device rigidly attached to the patient's head. However, most of such reference tools are either based on an invasive fixation technique or have physical limitations which allow mobility of the head only in a restricted range of motion after completion of the registration procedure.

Methods

A new sensor-based reference tool, the so-called Dynamic Reference Frame (DRF) which is designed to allow an unrestricted, 360° range of motion for the intraoperative use in pulsed DC magnetic navigation was tested in 40 patients. Different methods of non-invasive attachment dependent on the clinical need and type of procedure, as well as the resulting accuracies in the clinical application have been analyzed.

Results

Apart from conventional, completely rigid immobilization of the head (type A), four additional modes of head fixation and attachment of the DRF were distinguished on clinical grounds: type B1 = pin fixation plus oral DRF attachment; type B2 = pin fixation plus retroauricular DRF attachment; type C1 = free head positioning with oral DRF; and type C2 = free head positioning with retroauricular DRF. Mean fiducial registration errors (FRE) were as follows: type A interventions = 1.51 mm, B1 = 1.56 mm, B2 = 1.54 mm, C1 = 1.73 mm, and C2 = 1.75 mm. The mean position errors determined at the end of the intervention as a measure of application accuracy were: 1.45 mm in type A interventions, 1.26 mm in type B1, 1.44 mm in type B2, 1.86 mm in type C1, and 1.68 mm in type C2.

Conclusion

Rigid head immobilization guarantees most reliable accuracy in various types of frameless stereotaxy. The use of an additional DRF, however, increases the application scope of frameless stereotaxy to include e.g. procedures in which rigid pin fixation of the cranium is not required or desired. Thus, continuous tracking of head motion allows highly flexible variation of the surgical strategy including intraoperative repositioning of the patient without impairment of navigational accuracy as it ensures automatic correction of spatial distortion. With a dental cast for oral attachment and the alternative option of non-invasive retroauricular attachment, flexibility in the clinical use of the DRF is ensured.  相似文献   
89.

Purpose

PSA screening has been rehabilitated. PSA is not specific and can be elevated by benign reasons. Additionally, a subgroup of patients with prostate hyperplasia may harbor prostate cancer (PCa). During monitoring, the clinician aims to detect significant tumors in time, submitting patients to minimal psychological and physical burden, especially in men with high serum PSA and repeat biopsies. We aimed to determine long-term outcomes with respect to ANNA/C-TRUS ability to detect PCa with six targeted biopsies.

Methods

A subset of 71 patients were enrolled. During monitoring, they were subjected to primary, secondary, or even multiple prostate biopsies when needed. Protocol monitoring included PSA measurements, digital rectal examination (DRE) and imaging.

Results

The median follow-up was 12 years. Forty-one patients had a history of negative systematic random biopsies (1–3 sessions). Their age ranges 62–85 years, PSA 0.5–47.3 ng/ml, and the median prostate volume 11–255 cc. During monitoring, 15 patients were diagnosed with PCa. Only two harbored aggressive tumors. The median time to diagnosis was 6 years. All PCa patients are free from biochemical relapse. From the remaining 56 patients, 11 did not have any biopsies, 12 had one, 13 had two, and 20 had three or more biopsy sessions.

Conclusions

ANNA/C-TRUS is a useful method monitoring patients with a risk of PCa. 50–75% of the usually performed biopsy cores could be spared and, after 12 years, 97% of the patients were either without evidence of a PCa or were diagnosed with a good prognosis tumor.
  相似文献   
90.
The purpose of this study was to determine magnetic resonance imaging (MRI) findings relevant to synovial injury of the shoulder in patients with and without acute shoulder trauma. Three hundred and nine consecutive shoulder MRI studies (185—male, 124—female, 50 ± 15 years old) were retrospectively evaluated for findings suggestive of synovial injury including rupture and/or diverticulum of the joint capsule, bursa, and biceps tendon sheath (BTS), ganglion/synovial cyst, geyser phenomenon, and sequel of previous shoulder dislocation (Hill–Sachs deformity). Patients with one or more of these findings were included in the MR-positive group, whereas the remaining subjects were used as MR negatives. Based on their medical records, patients were also divided into trauma and non-trauma groups, and statistical analysis was performed to evaluate the association between the aforementioned MRI findings and history of shoulder trauma. Fifty-six patients were included in the MR-positive group and 253 in the MR-negative group. In MR-positive group, the incidence of capsular rupture (CR) and subacromial/subdeltoid (SASD) bursal rupture was higher in trauma patients, whereas the incidence of BTS diverticulum and ganglion cyst was higher in subjects without trauma. Significant association was found between the history of acute trauma and CR, SASD bursal rupture, BTS rupture, and Hill–Sachs deformity. In shoulder MR examination, presence of CR and/or SASD bursal rupture is strongly suggestive of acute shoulder trauma. In addition, BTS rupture and Hill–Sachs deformity are more prevalent in patients with acute shoulder trauma. The presence of these features should alert MRI readers to assess for additional trauma-related internal derangements, if a respective history has not been provided.  相似文献   
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