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991.

Objective

Thoracic endovascular aortic repair (TEVAR) has demonstrated encouraging results and is gaining increasing acceptance as a treatment option for aortic aneurysms and dissections. Yet, its role in managing proximal aortic pathologies is unknown—this is important because in proximal (Stanford type A) aortic dissections, 10% to 30% are not accepted for surgery and 30% to 50% are technically amenable for TEVAR. We describe our case series of type A aortic dissections treated by using TEVAR.

Methods

Between year 2009 and 2016, 12 patients with acute, subacute, or chronic type A aortic dissection with the proximal entry tear located between the coronaries and brachiocephalic artery were treated with TEVAR at 3 centers. Various stent-graft configurations were used to seal the proximal entry tear in the ascending aorta under rapid pacing.

Results

A total of 12 patients (9 male, 3 female), mean age 81 ± 7 years, EuroSCORE II 9.1 ± 4.5, underwent TEVAR for the treatment of type A aortic dissection. Procedural success was achieved in 11 of 12 patients (91.7%). There was 1 minor stroke and 1 intraprocedural death. No additional deaths were reported at 30 days. At 36 months, there were 4 further deaths (all from nonaortic causes). The mean survival of these 4 deceased was 23 months (range 15-36 months). Follow-up computed tomography demonstrated favorable aortic remodeling.

Conclusions

TEVAR is feasible and reveals promising early results in selected patients with type A aortic dissection who are poor candidates for surgical repair. The current iteration of stent-graft technology, however, needs to be adapted to features specific to the ascending aorta.  相似文献   
992.
This investigation assessed 99Tcm-HMPAO white blood cell (Tc-WBC) and 67Ga knee uptake indices before and after 90Y treatment in patients with intractable rheumatoid arthritis (RA) and correlated the uptake indices with the clinical score. Sixteen knee joints with RA were treated with intra-articular injection of 185 MBq of 90Y-silicate colloid (Amersham) flushed with 50 mg of hydrocortisone. Clinical score, quantitative 67Ga and Tc-WBC knee uptake indices were obtained before and three weeks after treatment. Our results showed that 9/16 (56%) had a good response and 7/16 (44%) had a poor response to 90Y injection. There was poor correlation between clinical improvement and changes in 67Ga and Tc-WBC knee uptake indices (r = 0.46 and 0.14, respectively). The correlation coefficient between changes in 67Ga and Tc-WBC knee uptake indices was 0.29.  相似文献   
993.
Two colloidal radiopharmaceuticals, Au-198 and Tc-99m antimony, were used to evaluate the lymphatic drainage of the testis in experimental animals and humans. One to 24 hours after direct intratesticular injection of Au-198 colloid in dogs and 4-6 hours after injection of Tc-99m antimony colloid in men, distribution within retroperitoneal lymph nodes was demonstrated. Uptake within the para-aortic lymph nodes primarily draining the testis was decreased following proximal ligation of the spermatic vessels in dogs. Testicular lymphoscintigraphy successfully demonstrated an intact spermatic cord lymphatic communication to the para-aortic nodes in five of six patients with chronic lower-extremity lymphedema. When the intact testicle and spermatic cord were transposed to the thigh in a patient with chronic lymphedema of the lower extremity, percutaneous pedal lymphoscintigraphy successfully demonstrated uptake within the para-aortic lymph nodes draining the ipsilateral testis.  相似文献   
994.
丝瓜叶化学成分研究   总被引:7,自引:1,他引:6  
梁龙  鲁灵恩  蔡元聪 《药学学报》1993,28(11):836-839
从丝瓜(Luffa cylinderica Roem)叶中分得三种成分,经光谱和化学方法确定其结构为21β-羟基丝石竹皂甙元(L-2),2α-羟基常春藤皂甙元-3-O-β-D-吡喃葡萄糖甙(L-8)和21β-羟基常春藤皂甙元-3-O-β-D-吡喃葡萄糖甙(L-10)。L-2和L-10为新的天然产物,依次命名为丝瓜素A(lucyin A)和丝瓜皂甙N(lucyoside N)。  相似文献   
995.
Odontogenic infections are a potential risk for patients who receive cervicofacial radiotherapy and should be treated before irradiation. Anaerobic microbial infections are the most common causes. This study assessed the value of the hypoxic imaging agent fluorine-18 fluoromisonidazole (FMISO) in detecting anaerobic odontogenic infections. Positron emission tomography (PET) imaging was performed at 2 h after injection of 370 MBq (10 mCi) of FMISO in 26 nasopharyngeal carcinoma patients and six controls with healthy teeth. Tomograms were interpreted visually to identify hypoxic foci in the jaw. All patients received thorough dental examinations as a pre-radiotherapy work-up. Fifty-one sites of periodontitis, 15 periodontal abscesses, 14 sites of dental caries with root canal infection, 23 sites of dental caries without root canal infection, and seven necrotic pulps were found by dental examination. Anaerobic pathogens were isolated from 12 patients. Increased uptake of FMISO was found at 45 out of 51 sites of periodontitis, all 15 sites of periodontal abscess, all 14 sites of dental caries with root canal infection, all seven sites of necrotic pulp and 15 sites of dental caries without obvious evidence of active root canal infection. No abnormal uptake was seen in the healthy teeth of patients or in the six controls. The diagnostic sensitivity, specificity, positive and negative predictive values, and accuracy of FMISO PET scan in detecting odontogenic infections were 93%, 97%, 84%, 99% and 96%, respectively.18F-fluoride ion bone scan done in three patients showed that18F-fluoride ion plays no role in the demonstration of anaerobic odontogenic infection. FMISO PET scan is a sensitive method for the detection of anaerobic odontogenic infections, and may play a complementary role in the evaluation of the dental condition of patients with head and neck tumours prior to radiation therapy.  相似文献   
996.
An autopilot for a transport aircraft is designed using mixed H2 and H∞ optimal control. The control law design technique allows real parameter uncertainty to be accounted for in the design process. The autopilot consists of an inner loop that controls aircraft heading in response to external commands and an outer loop that tracks a localizer beam so that the aircraft is properly aligned with the runway for landing. The problem formulation and the robust control law design technique allow a wide range of performance and robustness requirements to be met. Analysis of the closed-loop system shows the controller performance and robustness for a number of flight conditions through two separate approach profiles.  相似文献   
997.
A 46-year-old male patient who had long-term right ventricular (RV) pacing for symptomatic complete heart block, initially by an epicardial, later with an endocardial pacing lead at the RV apex, developed congestive heart failure (CHF) and chronic atrial fibrillation 7 years following the pacemaker implantation and was medically treated. During follow-up, his pacemaker was upgraded to a cardiac resynchronisation therapy (CRT) device, because of uncontrolled CHF symptoms, New York Heart Association (NYHA) functional class IV, while on drugs. The patient's symptomatic status improved to NYHA functional class II with CRT. After 17 months of CRT, the battery became depleted, because of the high capture threshold of the left ventricular lead. The patient was then given dual site RV pacing (RV outflow tract+RV apex) in place of CRT, which showed similar efficacy at 12 weeks follow-up.  相似文献   
998.
R L Mittl  I T Yeh  H Y Kressel 《Radiology》1991,180(1):81-83
A high-intensity rim surrounding uterine leiomyomas was identified on T2-weighted magnetic resonance (MR) images in five of 13 patients with histopathologically confirmed leiomyomas. These peripheral high-intensity rims were not associated with subject age or with size, location, or degeneration of the leiomyomas. Histologic examination revealed markedly dilated lymphatic vessels, dilated veins, edema, or a combination of these features to correspond to the location of the high-intensity rims. These benign causes of high intensity in the myometrium should not be confused with clinically important processes such as adenomyosis or invasion by endometrial carcinoma.  相似文献   
999.
In the retina of a variety of vertebrate species, a monoclonal antibody against protein kinase C (PKC) has been shown to label preferentially bipolar cells. Although the functional consequences of PKC activation in these cells is yet to be revealed, the present study was motivated in part by the possibility that the antibody might be used as a selective marker for examining the development of bipolar cells in the rat retina. Here, the developmental pattern and the dynamic changes of retinal cells expressing PKC-like immunoreactivity (PKC-LI) were studied and analyzed throughout postnatal life until adulthood. Upon its initial detection by immunohistochemistry on postnatal day (PD)-10, faint PKC-LI was limited to the central region of the retina, labeling cell bodies located at the scleral margin of the inner nuclear layer (INL) adjacent to the outer plexiform layer (OPL). On subsequent days, PKC-LI spread progressively to the peripheral retina and axon terminal bulbs at the vitreal margin of the inner plexiform layer (IPL) began showing the first signs of immunoreactive labeling. Not until PD-15, the time of eye opening, did PKC-LI in these cells increase to the extent such that their thin axons were immunoreactive. Each of these axons traversed the entire thickness of the IPL and divided into two or three short branches before ending as enlarged terminal bulbs. The morphology and the location of PKC-LI cells in both the developing and adult retina observed in our study are consistent with them being rod bipolar cells. By the end of the fourth postnatal week, the rod bipolar cells appeared mature, resembling those found in the adult.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
1000.
Gold  K.F.  Pastores  G.M.  Botteman  M.F.  Yeh  J.M.  Sweeney  S.  Aliski  W.  Pashos  C.L. 《Quality of life research》2002,11(4):317-327
This paper is the first of its kind to study the impact of Fabry disease (FD) in affected males, and shows that FD is associated with a significant decline in several domains. Using the medical outcomes study (MOS) SF-36 and a FD-specific questionnaire, we compared the observations found among these patients with that obtained for the general US population and other chronic disease states, including Gaucher disease (GD) (another lysosomal storage disorder), end-stage renal disease, stoke and AIDS. Patients with FD have a score profile most similar to patients with AIDS. In comparison with patients with GD, Fabry patients score substantially lower across all domains. Using simple linear regression, potential predictors of health-related quality of life (HRQOL) for Fabry patients were also determined. As in the general population, stroke, cardiac problems and renal disease lead to substantial decrement in HRQOL. In addition, two disease specific symptoms (acroparesthesia and anhidrosis) and pain are also predictors of decreased quality of life. Currently, no specific therapy for FD exists. As enzyme therapy for FD becomes increasingly available, it will be interesting to evaluate the therapy's impact on the quality of life of patients.  相似文献   
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