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71.
The effects of bulk versus particulate polymethylmethacrylate on bone   总被引:3,自引:0,他引:3  
Twenty-one mature New Zealand white female rabbits were allocated into three groups of seven rabbits. Group I received a bolus of doughy Simplex polymethylmethacrylate (PMMA) cement injected into the proximal tibia through a drill hole. Group II received a preformed, cooled, bulk PMMA pellet. Group III had particulate PMMA powder implanted. The operated, but nonimplanted, left tibiae served as controls. Animals were killed after four months. Histologically, both Group I and Group II demonstrated a thin, fibrous tissue membrane at the implant interface. Particulate PMMA (Group III) stimulated a much thicker, florid, foreign body reaction composed of histiocytes and giant cells. The foreign body response to particulate acrylic cement was similar to that seen in failed cemented joint replacement arthroplasty in humans.  相似文献   
72.
We investigated progressive telomere shortening in normal human epidermis and lingual epithelium during aging, and attempted, in particular, to ascertain whether the telomere shortening that accompanies aging occurs at the same rate in different tissues. We studied telomeric DNA integrity, and estimated annual telomere loss, in 52 specimens of epidermis and 48 specimens of lingual epithelium collected at autopsy from subjects who had died at ages between 0 and 101 y. Most of the DNA samples were measured twice by southern blot hybridization. In addition, the correlation between telomere lengths in the two types of tissues was examined. The telomere reduction rates in epidermis and lingual epithelium were 36 bp and 30 bp per y, respectively, and these were significantly different. The rates obtained by the second measurements in epidermis and lingual epithelium were 39 and 32 bp per y, respectively, and these were also significantly different. The mean telomere lengths in the epidermis of eight neonates and the lingual epithelium of seven neonates were 13.2+/-1.0 and 13.8+/-1.0 kb, respectively. Comparison of telomere lengths in the two tissues for 41 paired samples showed that the mean telomere length in the epidermis (10.7+/-2.3 kb) was less than that in the lingual epithelium (12.4+/-2.5 kb); however, statistical analysis revealed a very significant relationship between epidermal and lingual epithelial telomere length (r=0.842, p<0.0001). These results indicate that the telomeres in epidermis and lingual epithelium are characterized by tissue-specific loss rates.  相似文献   
73.
Gastrinoma is a rare endocrine tumor that is frequently associated with liver metastasis. The liver metastasis is usually seen simultaneously or soon after a primary operation. A 47-year-old woman who had had a total gastrectomy 20 years earlier developed liver metastasis. An interval of this length between surgery and metastasis is extremely rare. The total gastrectomy prevented the patient from developing the usual symptoms of hypergastrinemia that would have enabled early diagnosis of the metastasis. Laboratory examinations on admission revealed a high serum gastrin concentration (1500 pg/ml). Computed tomography showed an irregularly enhanced mass lesion with an uneven, low-density central area in the right anterior inferior segment of the liver. An extended right hepatectomy was performed. Intraoperative ultrasonography showed no abnormalities in the remnant pancreas. Examination of the cut surface of the specimen revealed a yellow, firm, elastic tumor, 55 mm in diameter. The interior of the tumor appeared necrotic. Histopathologically, the tumor was composed of cells with hyperchromatic, dysplastic nuclei arranged in a trabecular pattern with nest formation. Gastrin staining was positive. A histologic diagnosis of metastatic gastrinoma was made. The patient's gastrin concentration returned to normal and she was well at 2-year follow-up. Received: August 19, 1999 / Accepted: January 28, 2000  相似文献   
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Mycotic aneurysm is a rare but life-threatening disease that warrants an integrated therapeutic approach involving surgical intervention and prolonged antibiotic use. However, the causative organisms are often unidentified because antibiotics started empirically render blood and tissue cultures negative. Molecular diagnosis has been reported to be useful in such culture-negative cases. We report a case of a culture-negative mycotic aortic aneurysm due to Haemophilus influenzae, diagnosed by direct 16S rRNA polymerase chain reaction (PCR) and sequencing of the resected aneurysm tissue. PCR for serotype revealed type b, and PCR and sequencing of the ftsI gene revealed alterations in penicillin-binding protein 3, suggesting resistance to ampicillin. Multilocus sequence typing demonstrated that the isolate belonged to sequence type 54.  相似文献   
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After 70 years with no confirmed autochthonous cases of dengue fever in Japan, 19 cases were reported during August–September 2014. Dengue virus serotype 1 was detected in 18 patients. Phylogenetic analysis of the envelope protein genome sequence from 3 patients revealed 100% identity with the strain from the first patient (2014) in Japan.  相似文献   
79.
BackgroundIn complex congenital heart disease, supraventricular arrhythmia develops long term after surgical repair. The arrhythmia could have pharmacological tolerance and sometimes be fatal. We report our experiences with puncturing tough or calcified surgical repair material to access the pulmonary venous atrium for the purpose of the management of arrhythmia in complex congenital heart disease with surgical correction.MethodsFrom June 2016, subsequent 9 patients underwent the procedure. Their age at the procedure ranged from 11 to 43 years old (median 26.4 years old). Surgical procedures were Mustard procedure (Xenomedica?) in 6, lateral tunnel total cavo-pulmonary connection with autologous pericardium in 2, and extra-cardiac total cavo-pulmonary connection with expanded polytetrafluoroethylene (ePTFE) tube in 1.ResultsMulti-planar reconstruction imaging by cardiac computed tomography was done for making plans before the procedures. Under intracardiac echocardiography guidance, an 8 French steerable sheath was perpendicularly adjusted to target objects. The sharpened edge of 0.014 inch guide wire penetrated with gentle forward force. Subsequently, the puncture site was dilated from a small balloon to a large one step by step. In all patients, penetration was successfully completed. Catheter ablation was achieved in 8 patients and a pacemaker was implanted through the re-canalized superior caval vein in 1 patient. No complications were recorded.ConclusionThe trans-catheter puncture of the synthetic or calcified material is safe and feasible, although careful planning is required with imaging. A steerable sheath could easily be controlled to the make appropriate angle to the target object for preventing slippage and conveying effective force.  相似文献   
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