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151.
BACKGROUND AND PURPOSE: Helicobacter pylori infection is primarily acquired in early childhood and its transmission routes are debated. The aims of this study were to determine the seroprevalence of anti-H. pylori immunoglobulin G (IgG) in Taiwanese and to investigate whether a common mode of transmission could be shared between H. pylori and hepatitis A virus (HAV). METHODS: An enzyme-linked immunosorbent assay (ELISA) was used to investigate the prevalence of H. pylori among 924 healthy volunteers aged less than 40 years, and radioimmunoassay for HAV infection was conducted in 500 subjects from the same population. The kappa statistic was used to measure the difference in positivity for the 2 infections in a subgroup of 500 subjects who had their sera simultaneously tested for anti-H. pylori and anti-HAV antibodies. RESULTS: The seroprevalence of anti-H. pylori IgG was 16.7% in subjects aged < 16 years and 38.3% at ages >or= 16 years. Most children (99%) under the age of 16 were seronegative for HAV. The prevalence of H. pylori infection increased rapidly with age, at 1%/year and 0.8%/year for children and adults, respectively. The rate of H. pylori infection was higher in male (21%) than in female (12%) children (p < 0.01; OR, 2.0; 95% confidence interval, 1.2 to 3.0). No significant difference in seroprevalence between genders was noted in subjects aged >or= 16 years. The agreement in the trend of seropositivity between both infections in the age groups 1 to 10 years and 10 to 20 years was worse than chance (kappa = -0.56) and little better than chance (kappa = 0.01), respectively. CONCLUSIONS: Acquisition of H. pylori infection occurs at a young age, and male children are more likely to develop the infection. The main transmission route of HAV, the fecal-oral route, did not seem to be responsible for H. pylori transmission in this Taiwanese cohort.  相似文献   
152.
OBJECTIVE: We evaluated the long-term results of the Cox-Maze III procedure (CM-III) for persistent atrial fibrillation (AF) associated with rheumatic mitral valve (MV) disease. METHODS: We analyzed 127 patients who underwent the CM-III combined with a rheumatic MV procedure between 1994 and 2004. In-hospital mortalities were excluded from the study. RESULTS: There were 10 late deaths and the mean follow-up duration was 7.1+/-2.8 years (range, 13 months to 11.5 years). Normal sinus rhythm was restored in 88.2% (112/127) after the CM-III. Right atrial contractility was demonstrable in 100% (112/112) and left atrial contractility in 68.8% (77/112) of the patients restored to sinus rhythm. Fifteen patients never regained sinus rhythm after the CM-III (AF treatment failure). Permanent pacemakers were implanted in 4.7% (6/127) of the patients during the follow-up. Late recurrence of AF developed in 34 of 112 patients at 44+/-27 months postoperatively, and sinus rhythm was restored in 29 of 34 patients by administration of an antiarrhythmic medication. Independent risk factors for late AF recurrence were longer duration of AF (>60 months) (odds ratio (OR)=2.758, p=0.025), increased left atrial size (OR=1.113, p=0.004). Freedom from AF recurrence was 93% at 1-year, 82% at 3 years, 71% at 5 years, and 63% at 7 years. Risk factors for AF treatment failure were longer duration of AF (>60 months) (p<0.001) and increased patient age (p=0.030). A higher prevalence of significant late tricuspid regurgitation was observed in patients with AF treatment failure and those with late AF recurrence. CONCLUSIONS: The CM-III for persistent AF associated with rheumatic MV disease demonstrated a progressively decreased cure rate during the follow-up period. Early surgical therapy, aggressive left atrial reduction, and correction of tricuspid regurgitation at the time of surgery may increase the long-term success rate.  相似文献   
153.
Amniotic fluid mesenchymal stem cells have the ability to secrete neurotrophic factors that are able to promote neuron survival in vitro. The purpose of this study was to evaluate the effects of neurotrophic factors secreted by rat amniotic fluid mesenchymal stem cells on regeneration of sciatic nerve after crush injury. Fifty Sprague-Dawley rats weighing 250-300 g were used. The left sciatic nerve was crushed with a vessel clamp. Rat amniotic fluid mesenchymal stem cells embedded in fibrin glue were delivered to the injured nerve. Enzyme-linked immunosorbent assay (ELISA) and immunocytochemistry were used to detect neurotrophic factors secreted by the amniotic fluid mesenchymal stem cells. Nerve regeneration was assessed by motor function, electrophysiology, histology, and immunocytochemistry studies. Positive CD29/44, and negative CD11b/45, as well as high levels of expression of brain-derived neurotrophic factor, glia cell line-derived neurotrophic factor, ciliary neurotrophic factor (CNTF), nerve growth factor, and neurotrophin-3 (NT-3) were demonstrated in amniotic fluid mesenchymal stem cells. Motor function recovery, the compound muscle action potential, and nerve conduction latency showed significant improvement in rats treated with amniotic fluid mesenchymal stem cells. ELISA measurement in retrieved nerves displayed statistically significant elevation of CNTF and NT-3. The immunocytochemical studies demonstrated positive staining for NT-3 and CNTF in transplanted cells. The histology and immunocytochemistry studies revealed less fibrosis and a high level of expression of S-100 and glial fibrillary acid protein at the crush site. Rat amniotic fluid mesenchymal stem cells may facilitate regeneration in the sciatic nerve after crush injury. The increased nerve regeneration found in this study may be due to the neurotrophic factors secreted by amniotic fluid mesenchymal stem cells.  相似文献   
154.
OBJECTIVE: The recent development of fetal ultrasonography has allowed for an increasing number of prenatal diagnoses for congenital cystic adenomatoid malformation (CCAM). However, the appropriate surgical timing of these patients has not been studied as of yet. The aim of this study is to suggest a safe strategy for the treatment of CCAM by identifying the relationship between the timing of surgery and postoperative outcome. METHODS: Between 1987 and 2003, 40 patients (28 males, 12 females) underwent surgical resection for CCAM. The mean age was 38.6+/-9.1 (2 days-13 years) months. CCAM was diagnosed by prenatal ultrasonography in eight patients. Early operations were performed in four out of the eight. Operation was deferred until 2-12 months of age for the remaining four patients. RESULTS: Type I CCAM was found in 20 patients, type II in 20 and no patient exhibited type III. Five patients had associated pectus excavatum anomaly. There were no cases of operative mortality. Seventeen minor postoperative complications developed in 16 patients (40.0%): prolonged chest tube drain in 10, wound infection in 4, and 1 case of pneumonia, empyema and pleural space, respectively. The average hospital stay was 11.8 (6-29) days. During the mean follow-up period of 67.5 months, one patient died of accidental aspiration 7 months after operation during the postoperative recovery course of Ravich operation for pectus excavatum. The remaining patients reported doing well with normal physical activity. All five patients who underwent surgery at the age of under 1 month did not exhibit increased postoperative morbidity. CONCLUSIONS: We concluded that surgery for CCAM could be safely performed in all age groups with satisfactory long-term outcomes. It is suggested that early elective surgical correction can be recommended for a patient whose diagnosis was made in utero.  相似文献   
155.
156.
This in vitro biomechanical study used cadaveric specimens to compare the rotator cuff repair fixation provided by BioCorkscrew and Bioknotless RC suture anchors. Three cm wide by 1-cm long full-thickness supraspinatus defects were repaired using either two BioCorkscrew suture anchors with combined vertical and horizontal mattress sutures (n = 7) or three Bioknotless RC suture anchors with simple sutures (n = 7). Therefore, the BioCorkscrew suture anchor group had two sutures per anchor (four total sutures), while the Bioknotless RC suture anchor group had one suture per anchor (three total sutures). Two-phase cyclic (5–100 N, 1,000 cycles and 5–180 N, 2,000 cycles) and load to failure tests (31 mm/s) were performed. Non-parametric statistics were used to compare group differences (P < 0.05). All of the BioCorkscrew group specimens (seven of seven) completed the two phase cyclic test regimen without failure or gapping ≥ 5 mm, compared to only three of seven of the Bioknotless RC group (Fisher’s Exact test = 0.03). Groups did not differ for repair site gapping during the 5–100 N cyclic test phase (Fisher’s Exact test = 0.77), however more of the Bioknotless RC group displayed gapping ≥ 5 mm during the 5–180 N cyclic test phase than the BioCorkscrew group (P = 0.02). The BioCorkscrew group also displayed greater yield load during load to failure testing (492.2 ± 204 N vs. 296.4 ± 155 N, P = 0.03). In this in vitro biomechanical study, the BioCorkscrew group with combined vertical and horizontal mattress sutures displayed greater cyclic test survival, less repair site gapping, and superior yield load compared to the Bioknotless RC group with simple sutures. These results in human cadaveric rotator cuff-humerus specimens suggest better immediate post-operative repair site strength and a reduced need for post-operative restrictions. Clinical studies are needed to determine how these rotator cuff repair modes withstand the forces of early rehabilitation and activities of daily living that potentially influence patient outcomes.  相似文献   
157.
Considerable debate exists regarding the continuity of bipolar disorder (BD) in children and adolescents. Do affected children continue to have BD as adults? Are pediatric forms of BD distinct from adult forms of the disorder? Here, I argue that, in fact, strictly defined BD I and II in children and adolescents is continuous with adult BD. First, if we take developmental differences into account, children and adults share similar symptoms, since they are both diagnosed according to DSM-IV criteria. Next, retrospective studies indicate that 50% to 66% of adults with BD had onset of their disorder before age 19 years. Early prospective data indicate that adolescents with BD progress to become young adults with BD. Further, family studies of pediatric BD probands find high rates of BD in adult relatives, and pediatric offspring of parents with BD have elevated rates of BD, compared with control subjects. Finally, biological characteristics of pediatric BD (such as treatment response, neurobiology, and genetics) are either shared with adults having BD or fit logically into developmental models of BD. Thus, while not conclusive, a preponderance of data support the hypothesis that pediatric BD is continuous with adult BD. Prospective studies incorporating phenomenological and biological assessment are needed to decisively address this issue.  相似文献   
158.
Adult septic cavernous sinus thrombosis (CST) due to Streptococcus constellatus infection has not been reported. We report a case of CST due to S. constellatus in a 39-year-old man who had typical presentations of septic CST including headache, fever, and ophthalmoplegia, with an evolving course for 10 days before he was sent to our emergency room. Cranial magnetic resonance imaging (MRI) study revealed CST, which was confirmed by cerebral angiography study. Multiple positive blood cultures grew viridans streptococci and further species identification with conventional methods, API-20 STREPT system analysis, and polymerase chain reaction sequencing of bacterial 16S rRNA revealed S. constellatus. The presence of sphenoid sinusitis in this patient was also demonstrated by cranial MRI study, and the presence of meningitis by meningeal irritation signs and inflammatory cerebrospinal fluid (CSF) findings. Chronic alcohol consumption for more than 10 years was the only predisposing condition to this infection. He had a full recovery after 6 weeks of intravenous penicillin G therapy (24 x 10(6) U/day). Almost complete regression of cavernous sinus lesion and resolution of sphenoid sinusitis were shown on follow-up cranial MRI study about 6 months later.  相似文献   
159.
The primary objective of revascularization procedures in the posterior circulation is the prevention of vertebrobasilar ischemic stroke. Specific anatomical and neurophysiologic characteristics such as posterior communicating artery size affect the susceptibility to ischemia. Current indications for revascularization include symptomatic vertebrobasilar ischemia refractory to medical therapy and ischemia caused by parent vessel occlusion as treatment for complex aneurysms. Treatment options include endovascular angioplasty and stenting, surgical endarterectomy, arterial reimplantation, extracranial-to-intracranial anastomosis, and indirect bypasses. Pretreatment studies including cerebral blood flow measurements with assessment of hemodynamic reserve can affect treatment decisions. Careful blood pressure regulation, neurophysiologic monitoring, and neuroprotective measures such as mild brain hypothermia can help minimize the risks of intervention. Microscope, microinstruments and intraoperative Doppler are routinely used. The superficial temporal artery, occipital artery, and external carotid artery can be used to augment blood flow to the superior cerebellar artery, posterior cerebral artery, posterior inferior cerebellar artery, or anterior inferior cerebellar artery. Interposition venous or arterial grafts can be used to increase length. Several published series report improvement or relief of symptoms in 60 to 100% of patients with a reduction of risk of future stroke and low complication rates.  相似文献   
160.
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