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991.
A high-throughput multiplex bead suspension array was developed for the rapid subgenogrouping of EV71 strains, based on single nucleotide polymorphisms observed within the VP1 region with a high sensitivity as low as 1 PFU. Of 33 viral isolates and 55 clinical samples, all EV71 strains were successfully detected and correctly subgenogrouped.  相似文献   
992.
The bellows-type pneumatic ventricular assist device (VAD) generates pneumatic pressure with compression of bellows instead of using an air compressor. This VAD driver has a small volume that is suitable for portable devices. However, improper pneumatic pressure setup can not only cause a lack of adequate flow generation, but also cause durability problems. In this study, a pneumatic pressure regulation system for optimal operation of the bellows-type VAD has been developed. The optimal pneumatic pressure conditions according to various afterload conditions aiming for optimal flow rates were investigated, and an afterload estimation algorithm was developed. The developed regulation system, which consists of a pressure sensor and a two-way solenoid valve, estimates the current afterload and regulates the pneumatic pressure to the optimal point for the current afterload condition. Experiments were performed in a mock circulation system. The afterload estimation algorithm showed sufficient performance with the standard deviation of error, 8.8 mm Hg. The flow rate could be stably regulated with a developed system under various afterload conditions. The shortcoming of a bellows-type VAD could be handled with this simple pressure regulation system.  相似文献   
993.
In this study, we developed a small pneumatic actuator that can be used as an extracorporeal biventricular assist device. It incorporated a bellows-transforming mechanism to generate blood-pumping pressure. The cylindrical unit is 88 ± 0.1 mm high, has a diameter of 150 ±  0.1 mm, and weighs 2.4 ± 0.01 kg. In vitro, maximal outflow at the highest pumping rate (PR) exceeded 8 L/min when two 55 mL blood sacs were used under an afterload pressure of 100 mm Hg. At a pumping rate of 100 beats per minute (bpm), maximal hydraulic efficiency was 9.34% when the unit supported a single ventricle and 13.8% when it supported both ventricles. Moreover, pneumatic efficiencies of the actuator were 17.3% and 33.1% for LVAD and BVAD applications, respectively. The energy equivalent pressure was 62.78∼208.10 mm Hg at a PR of 60∼100 bpm, and the maximal value of dP/dt during systole was 1269 mm Hg/s at a PR of 60 bpm and 979 mm Hg/s at a PR of 100 bpm. When the unit was applied to 15 calves, it stably pumped 3∼4 L/min of blood at 60 bpm, and no mechanical malfunction was experienced over 125 days of operation. We conclude that the presently developed pneumatic actuator can be utilized as an extracorporeal biventricular assist device.  相似文献   
994.
995.
Displaced neck of femur fracture is a common clinical problem among the elderly population. Our aim is to review previously published randomized controlled trials to establish if total hip arthroplasty (THA) or hemiarthroplasty will offer a superior clinical outcome in this group of patients. We conducted literature search for relevant randomized controlled trials. A total of 407 patients from 3 trials were included in this meta-analysis. In the long-term follow-up, we found that THA patients were able to ambulate better, reported less pain compared with their hemiarthroplasty counterparts, and were less likely to undergo a repeated hip surgery. Considering the more favorable long-term outcomes in THA patients, we conclude that there may be a case to offer THA as the primary treatment of these patients.  相似文献   
996.

Objectives

To describe surgical strategies using cerebral revascularization for complex middle cerebral artery aneurysms unsuitable to microsurgical clipping.

Materials and methods

In this study, the clinical features, case management, and results in 9 consecutive patients who underwent 10 cerebral revascularization procedures between January 1999 and April 2008 were retrospectively analyzed. The patient population consisted of 6 men and 3 women whose ages ranged from 15 to 71 years (mean, 42.4 years). The size of the aneurysms ranged from 12 to 35 mm (mean, 24.3 mm). Treated aneurysms were located in the M1 segment in 2 patients, the middle cerebral artery (MCA) bifurcation in 3 patients, the distal M3 segment in 3 patients, and the anterior temporal artery (ATA; the early cortical branch of the M1 segment) in 1 patient. A total of 10 revascularizations were performed. Three aneurysms were saccular and six aneurysms were fusiform. For the fusiform aneurysms of the M1 segment in 2 patients, superficial temporal artery (STA) trunk–saphenous vein (SV)–MCA bypasses followed by trapping were performed. For the large saccular MCA bifurcation aneurysms in 3 patients, STA–MCA bypasses followed by complete neck clipping, including the revascularized branch with the preservation of the flow of the other branch, were performed in 2 cases, and a STA trunk–SV–MCA bypass secondary to direct neck clipping with the preservation of both M2 branches was performed in 1 case. For the fusiform distal MCA aneurysms, STA–MCA bypasses in 2 patients and in situ MCA–MCA bypasses in 2 patients were performed. In one case involving distal MCA fusiform aneurysm, STA–MCA bypass and MCA–MCA bypass were performed simultaneously. In a case involving fusiform ATA aneurysm, primary reanastomosis after aneurysm excision was performed in 1 patient.

Results

The post-operative 3-month Glasgow outcome scales were good recovery in 6 patients, severe disability in 1 patient, a vegetative state in 1 patient, and death in 1 patient. A follow-up angiography was performed in 6 patients and revealed a patent bypass in 5 patients. In one case treated by direct neck clipping secondary to cerebral revascularization, the angiography obtained 2 weeks later showed graft occlusion, but there were no neurologic symptoms. Among the unfavorable outcomes of 3 patients who did not undergo follow-up angiography, surgery-related morbidity secondary to cerebral infarction was due to the size discrepancy between the donor and recipient vessels in 1 patient with severe disability. In the other 2 patients, the preoperative conditions were Hunt and Hess grade V.

Conclusions

Cerebral revascularization is a safe and effective technique of treatment for selective cases of complex large or giant aneurysms and unclippable fusiform aneurysms in the MCA.  相似文献   
997.
The prevalence of reflux esophagitis is increasing in Korea. To estimate the prevalence and clinical characteristics of reflux esophagitis in healthy subjects, we retrospectively examined the medical records of healthy subjects undergoing a routine check-up from October 2004 to September 2005. A total of 6,082 (3,590 men, mean age 44±10 yr) subjects were enrolled in this study. The prevalence of reflux esophagitis in healthy subjects was 10.5%. According to the univariate analysis, male sex (odds ratio [OR] 3.49, 95% confidence interval [CI] 2.84-4.30), smoking history (OR 1.91, 95% CI 1.60-2.28), body mass index (BMI) >30 kg/m2 (OR 2.13, 95% CI 1.37-3.33), total cholesterol >250 mg/dL (OR 1.50, 95% CI 1.05-2.14), low-density lipoprotein (LDL) cholesterol ≥160 mg/dL (OR 1.52, 95% CI 1.08-2.14), triglyceride ≥150 mg/dL (OR 1.92, 95% CI 1.61-2.30), high blood pressure (BP) (OR 1.46, 95% CI 1.20-1.76), and fasting glucose ≥110 mg/dL (OR 1.45, 95% CI 1.13-1.86) were significantly associated with reflux esophagitis (all p<0.05). However, age, alcohol drinking and Helicobacter pylori infection were not associated with reflux esophagitis. In conclusiosn, significant relationships of reflux esophagitis with obesity, low high-density lipoprotein (HDL) cholesterol, high triglyceride, high BP, and elevated fasting glucose suggested that reflux esophagitis might represent the disease spectrum of the metabolic syndrome.  相似文献   
998.
We herein describe a case of cystic lymphangioma in the greater omentum of the remnant stomach, which is thought it to be related with subtotal gastrectomy 10 yr ago for early gastric cancer. A 76-yr-old man was admitted to our department with postprandial abdominal discomfort and bowel habit change. Intraabdominal multilocular cystic mass was detected by ultrasonography and computed tomography. We performed a complete En-bloc tumor resection including spleen and distal pancreas, and histological examination confirmed cystic lymphangioma originated from the greater omentum of the remnant stomach. Although the etiology of omental lymphangioma remains largely unclear, these findings suggested strongly that obstruction of the lymphatic vessels after gastric resection for gastric carcinoma might be the most plausible cause. The surgical extirpation with resection of organs involved appears to be a treatment of choice for such unusual case.  相似文献   
999.
Neuroblastomas originating from different sites might have different clinical and biological characteristics. In the present study, the clinical (age, sex and stage) and biological (N-myc amplification, Shimada pathology and levels of lactate dehydrogenase, ferritin and neuron-specific enolase) characteristics of patients with newly diagnosed neuroblastoma were compared according to the site of tumor origin (extra-abdominal versus abdominal). The event-free survival rate (EFS) was also compared between the two groups. Among 143 neuroblastomas, 115 tumors originated from the abdomen, 26 from extra-abdominal sites and 2 from unknown primary sites. Frequencies of stage 4 tumor and N-myc amplified tumor were lower in the extra-abdominal group than in the abdominal group (34.6% vs. 60.0%, P=0.019 and 4.2% vs. 45.0%, P<0.001, respectively). Levels of lactate dehydrogenase, ferritin and neuron-specific enolase were significantly lower in the extra-abdominal group than in the abdominal group. The probability of 5-yr EFS (±95% confidence interval) was higher in the extra-abdominal group than in the abdominal group (94.4±10.6% vs. 69.4±9.4%, P=0.026). Taken together, neuroblastomas originating from extra-abdominal sites might be associated with more favorable clinical and biological characteristics and a better outcome than neuroblastomas originating from abdomen.  相似文献   
1000.
This report is about the case of gastritis associated with capillariasis. The patient was a 52-yr-old Korean woman who occasionally ate raw fish and chicken. She complained of mild abdominal pain and nausea, but not diarrhea. An endoscopic examination revealed an exudative flat erosive change on the gastric mucosa of the antrum. She was microscopically diagnosed as chronic gastritis with numerous eosinophil infiltrations. The sectioned worms and eggs in mucosa were morphologically regarded as belonging to the genus Capillaria. This is the first case of gastric capillariasis reported in the Republic of Korea.  相似文献   
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