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11.
12.

Purpose

This study aimed at comparing the development of tricuspid and mitral regurgitation between the right ventricular outflow tract (RVOT) and right ventricular apex (RVA) pacing.

Methods

We prospectively enrolled 164 patients for permanent pacemaker implantation due to sick sinus syndrome or atrioventricular block and randomly divided them into two equal groups to receive either RVOT or RVA pacing. Patients with heart failure or valvular disease were excluded. The post-procedural echocardiographic evaluations were performed 1 year after the pre-procedural echocardiography, and the results were compared with respect to the development of mitral and tricuspid regurgitation and probable changes in the ejection fraction (EF).

Results

Age, gender, pacing mode, and baseline cardiac rhythm did not significantly differ between the RVOT and RVA pacing groups. The incidence of mitral regurgitation was significantly higher in the RVA group (p?=?0.03), but the incidence of tricuspid regurgitation was similar in both groups. There was a trend toward less tricuspid regurgitation in the RVOT group; however, it was not statistically significant. The mean EF was not significantly different between the study groups.

Conclusion

It seems that the incidence of mitral regurgitation in RVA pacing is significantly higher than that in RVOT pacing. The formation of tricuspid regurgitation needs to be discussed in the future.

Clinical trial registration number

IRCT201103146061N1  相似文献   
13.
11h is a very potent inhibitor against epidermal growth factor receptor triple mutation L858R/T790M/C797S (EGFRTM) with 13‐fold stronger potency than the FDA‐approved osimertinib. Recently, two new EGFRTM inhibitors, 11d and 11e , were reported which revealed 2.8‐ and 2.3‐fold stronger potency than 11h , respectively. 11h , 11d, and 11e have the same structures but differ only in their aliphatic chain length. However, the exact effects of differential aliphatic chain length on the inhibitory potencies of these compounds require further elaboration at the atomistic level, hence the objective of this report. Various computational tools were employed for this purpose. From our findings, it was revealed that van der Waals (vdW) interactions modulate the binding mechanisms of these inhibitors and play the most important role in the differential inhibitory activities of 11d , 11h, and 11e . The strong hydrogen bond formation between the aliphatic chain of 11d and key residue ARG841 was recognized as the reason for its higher activity and inhibitory potency relative to 11h and 11e . Moreover, the extension of the N‐terminal loop into the active site for vdW interaction with the phenyl group of 11e and carbon–hydrogen bond formed between the aliphatic chain of 11e and LEU718 engendered a higher activity of 11e than 11h .  相似文献   
14.
15.

Background:

Percutaneous vertebroplasty (PVP) is more commonly used for osteoporotic compression fractures (OCFs) and osteolytic vertebral body tumors. This study aimed to study the differences between OCFs and vertebral hemangiomas (VHs) treated with PVP.

Materials and Methods:

Between September 2007 and January 2010, we prospectively treated 28 consecutive patients of OCFs (43 recently symptomatic OCFs) and 24 cases of VHs (26 VHs). We used visual analogue scale (VAS) pain and Oswestry Disability Index (ODI) to evaluate the patients. The followup period in group 1 and 2 were 25.1 months (range 12 - 31 months) and 21.3 months (range 14 - 28 months), respectively. Comparison of means was carried out with the Chi Square Tests, t-test, and N Par-Test for multiple comparisons, whenever appropriate. The level of statistical significance was set at P < 0.05.

Results:

Following PVP the VAS score decreased to 4.57 and 4.17 in group 1 and 2, respectively. The ODI scores were 32.5% and 30%, respectively. This decrease in ODI scores lasted throughout the followup period.

Conclusions:

Although the preoperative scores were significantly different between group 1 and 2, there was no significant difference between two groups following the PVP.  相似文献   
16.
17.

Objective

Myelomeningocele is a complex central nervous system malformation mostly associated with other neural and extraneural anomalies. A rare special feature of the forehead and skull was observed in myelomeningocele. Here, we present several patients with myelomeningocele, severe hydrocephalus, and interfrontal encephalocele accompanied by metopic suture widening and abnormally shaped frontal bones.

Methods

Five children with this feature were enrolled in this series. The age, sex, location of myelomeningocele sac, neurological deficits, hydrocephalus and history of shunt surgery, and follow-up period were evaluated.

Results

Patients were aged from 1 to 12 months (mean, 6 months). All patients were male. Most sacs were located in lumbar and lumbosacral areas. Neurological deficits varying from only sphincter problem to paraplegia were found in all patients. Hydrocephalus was found in all children that needed a shunt procedure. Asymptomatic Chiari malformation, interfrontal encephalocele, and corpus callosum agenesis were evident in five, five, and three patients, respectively.

Conclusion

Anterior fontanel anomalies known as interfrontal encephalocele associated with myelomeningocele have been reported before. The patients have an open metopic suture extending widely to the nasal radix producing hypertelorism accompanied by interfrontal herniation of frontal lobes. The associated hydrocephalus exaggerates the anomaly. Treatment of accompanying hydrocephalus is advised to decrease the severity of frontal lobe herniation. Some patients may need frontal bone reconstruction surgery to provide cosmetic correction at the place of the midline frontal bone defect.  相似文献   
18.
In LeFort I surgery, the separation of the pterygomaxillary junction is done by osteotomy. Although the osteotome is positioned too close to the maxillary artery and its branches during pterygomaxillary separation, postoperative complications from vascular injuries are uncommon. We describe an unusual occurrence of a maxillary artery pseudoaneurysm after LeFort I and bilateral sagittal split osteotomies for maxillary advancement and mandibular setback as well as (anterior sliding) genioplasty. In a patient with class III occlusion and midface retrusion, the significant bleeding began 10 days postoperatively, which was controlled by anterior and posterior nasal packing. The bleeding recurred 28 days after surgery; thus, vascular anatomy in the pterygomaxillary area is reviewed, pseudoaneurysm was diagnosed on selective carotid angiography and successfully treated by embolization; and 2-year follow up was uneventful.  相似文献   
19.
AIM: To assess the efficacy, safety, stability and predictability of an implantable Phakic contact lens in patients with stable keratoconus. METHODS: The uncorrected and the best corrected visual acuity, defocus curve, contrast sensitivity, refraction and possible side effects were measured in 14 patients after utilizing implantable phakic contact lens (IPCL) to correct refractive errors. The result was assessed for more than 6mo. RESULTS: The mean preoperative spherical equivalent (SE) and astigmatism got changed from -6.94±2.79 DS and -4.24±1.42 DC to -0.23±0.43 DS and -1.05±0.49 DC, respectively at the last examination after 6mo. Before the preoperative the mean Snellen visual acuity was 0.18±0.10 logMAR. The mean uncorrected and the best corrected visual acuity got changed to 0.13±0.10 logMAR and 0.05±0.15 logMAR, respectively in 6mo. The mean safety indices were 1.11. There was no loss of visual acuity in any of the eyes and 22 eyes (78.5%) gained one or more lines. Twenty eyes (71.4%) were within 0.50 ?D and 27 (96.42%) were within ±1.00?D of the desired SE refraction. There was a change in manifest refraction of -0.23±0.43 (range from -1.00 to +0.75) from the first week of surgery to 6mo. Contrast sensitivity got improvement value at 3 per degree (P<0.005) after Toric IPCL implantation. The total 6mo corneal endothelial cell loss (ECL) was <5%. Intraocular pressure (IOP) was 11.32±2.28 mm Hg after 6mo. CONCLUSION: The clinical consequences of the present study exhibit the efficacy, safety, and predictability of Toric implantable Phakic contact lens in the correction of myopia and myopic astigmatism related with stable keratoconus.  相似文献   
20.

Background

Giardia lamblia is one of the most prevalent intestinal flagellate protozoa that infects a wide range of vertebrate hosts causing severe intestinal disorder in children.This study was performed to determine subspecies of G.lamblia by the PCR-RFLP method, targeting the glutamate dehydrogenase(gdh)locus, in hospitalized children at Urmia Mutahhari Hospital, West Azerbaijan Province,Iran and determining the infection transformational storages in this area.

Methods

Overall, 720 stool specimens were collected from the hospitalized children, 34 samples were positive and Giardia cysts were detected under the microscope. Cysts were partially purified by the sucrose density gradient method and then washed with sterile distilled water to remove effectively the PCR inhibitors. Genomic DNA of G. lamblia isolates was extracted by freeze-thaw cycles followed by phenol/ chloroform/isoamyl alcohol method. The single step PCR-RFLP assay was used to differentiate the assemblages between A and B, which were found in humans. In this method, 432 bp expected size was amplified, and then for detection of subspecies, specific restriction RsaI and BspLI enzymes were used.

Results

Totally 34 samples were positive in terms of Giardia cyst out of 720 examined samples microscopically, so the parasite spread rate is reported 4.72%. Analysis PCR-RFLP on these samples revealed that 28 samples (93.3%) have the genotype BIII and 2 samples (6.7%) belong to the subgroup BIV.

Conclusion

PCR-RFLP is a proper analytical method for determining the genotype among parasite types, using the glutamate dehydrogenizes zone’s genes. Based on the results, an animal origin of infection cycle is suggested.  相似文献   
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