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81.

Objectives

Ballistic injuries to peripheral nerves pose special challenges in terms of indications, timing and type of surgical intervention. The aim of the present work was to analyze our experience in the surgical treatment of peripheral nerve ballistic injuries with respect to the mechanism of injury (gunshot versus shrapnel), and identify common and dissimilar prognostic factors in both types of injury.

Methods

This study was conducted on 42 patients totaling 58 nerves. Twenty-two patients (32 nerves) were injured by gunshot and 20 patients (26 nerves) by shrapnel. Median postoperative follow-up was 33 months (range 12 months to 14 years).

Results

Overall postoperative outcome appears to be more favorable for gunshot-wound (GSW) patients than shrapnel-injured patients, especially in terms of neuropathic pain relief (75 % vs. 58 % respectively, p < 0.05). Presence of foreign particles in shrapnel injured patients has a negative impact on the surgical outcome in terms of rate of pain improvement (28 % compared to 67 % in patients with and without foreign particles, respectively). Nerve graft reconstruction, rather than neurolysis, seems to be the more beneficial treatment for shrapnel-induced neuropathic pain (100 % vs. 47 % in improvement rate, respectively). Early surgical intervention (median 2 months after injury) significantly relieved neuropathic pain in 83 % of shrapnel-injured patients compared to 58 % in patients operated later.

Conclusions

This study suggests that shrapnel injury is more destructive for nerve tissue than gunshot injury. Our impression is that early surgical intervention in shrapnel injuries and split nerve grafting (especially when small fragments are recognized in the nerve) significantly improve the patient’s functional activity and quality of life.  相似文献   
82.
For vascular occlusive disease, an autologous vein graft is the most suitable conduit for arterial reconstruction. Intimal hyperplasia, resulting from the migration and proliferation of vascular smooth muscle cells, is a major obstacle to patency after vein grafting. The degree to which the function of nitric oxide (NO) in the vein graft is preserved has been reported to be associated with the magnitude of intimal hyperplasia. Serotonin (5-HT) is released from platelets in the vascular system and plays physiological roles in controlling the vascular tone. The subtype receptors contributing to the 5-HT-induced mechanical responses vary by vessel type (artery and vein) and among species (dogs, rabbits, rats, and so on). Recent studies have demonstrated that 5-HT induces vasoconstriction through the activation of 5-HT2A receptors in smooth muscle cells or vasodilatation through the activation of endothelial 5-HT1B receptors in arteries from various animals. However, the effects of 5-HT have not been clarified in grafted veins. We herein demonstrate the responses to 5-HT in un-operated veins and then autogenous vein grafts. Next, we describe the effects of chronic in vivo administration of Rho-kinase inhibitors and 5-HT2A receptor antagonists, both of which reduce the 5-HT-induced contraction and intimal hyperplasia in vein grafts. Further studies targeting 5-HT are required to evaluate its possible benefits for autologous vein grafts with respect to vasospasm, function, and patency.  相似文献   
83.
A worldwide increase in antimicrobial‐resistant microbes due to the improper use of antimicrobial agents, along with a lack of progress in developing new antimicrobials, is becoming a societal problem. Although carbapenem‐resistant Enterobacteriaceae, which are resistant to carbapenem antimicrobials, first appeared in 1993, treatment options remain limited. Mechanisms behind antimicrobial resistance involve changes to microbial outer membranes, drug efflux pump abnormalities, β‐lactamase production and the creation of biofilms around cell bodies. Genetic information related to these forms of antimicrobial resistance exists on chromosomes and plasmids, and when located on the latter can easily be transmitted to other strains, no matter the species, which creates a risk of antimicrobial resistance spreading exceptionally rapidly. To prevent the spread of antimicrobial resistance, the World Health Organization in 2015 published an action plan on antimicrobial resistance, based on which World Health Organization member countries have laid out specific policies and targets. Urinary tract infections are a type of healthcare‐associated infection, and the sexually transmitted disease pathogen, Neisseria gonorrhoeae, has been included in a list of microbes that pose a risk to human health published by the US Centers for Disease Control and Prevention. Urologists face numerous problems when attempting to use antimicrobials properly, which is one method of dealing with antimicrobial resistance. Therefore, this article describes the current state of resistant microbes associated with urinary tract infections and countermeasures for antimicrobial resistance, including new antimicrobials.  相似文献   
84.
BACKGROUND: Graft-to-tunnel healing is a significant factor in anterior cruciate ligament reconstruction, but there have been few studies on the effect of graft-tunnel diameter disparity on intraosseous healing of the flexor tendon graft. HYPOTHESIS: Graft-tunnel diameter disparity of 2 mm has no effect on the pull-out strength of the graft from the bone tunnel. STUDY DESIGN: Controlled laboratory study. METHODS: Forty-two beagle dogs were divided into three groups. In each animal, reconstruction was performed in the left knee by using a 4-mm diameter autogenous flexor tendon for groups 1 and 2 and by using a 4-mm wide bone-patellar tendon-bone graft in group 3. A 4-mm diameter tunnel was drilled in the tibia of groups 1 and 3 and a 6-mm diameter tunnel, in group 2. In each group, seven animals were sacrificed at 3 and 6 weeks. RESULTS: The perpendicular fibers connecting the graft to the bone were generated in groups 1 and 2, and the number appeared to be higher in group 2, where the space was greater. There was no significant difference in the ultimate failure load between groups 1 and 2 at each period. CONCLUSION: Graft-tunnel diameter disparity of up to 2 mm may not adversely affect intraosseous healing of the flexor tendon graft. CLINICAL RELEVANCE: Surgeons need not be overly concerned about minor graft-tunnel diameter disparities.  相似文献   
85.
The purpose of the study was to investigate factors predicting injuries to the heart and/or thoracic aorta (H/TA) of unrestrained drivers in frontal motor vehicle collisions. We retrospectively analyzed findings of forensic autopsies of 37 unrestrained drivers of automobiles without airbags involved in frontal collisions. Mechanisms of injury, injury severity, presence of major injuries, and the number of fractured ribs were examined in each case. Victims were subdivided for comparison into those with (19 cases) and without (18 cases) H/TA injuries. The injury severity score and the abbreviated injury scale of the chest were significantly higher in persons with H/TA injuries (65.3+/-15.7 and 5.4+/-0.9) than in persons without (31.6+/-22.0 and 1.8+/-1.9). Because univariate analysis showed that the presence of multiple fractured ribs was an important predictor of H/TA injuries, we examined the relation between H/TA injuries and the number of fractured ribs. Copas's nonparametric smooth binary regression model showed that H/TA injuries were more likely in persons with eight or more fractured ribs. The presence of eight or more fractured ribs predicts H/TA injuries in unrestrained drivers.  相似文献   
86.

Purpose

Children with neurologic and neuromuscular handicaps frequently have various symptoms related to gastroesophageal reflux (GER) disease. The long-term efficacy of antireflux surgery remains controversial in such children with GER. The clinical results of such patients who underwent laparoscopic fundoplication were examined in the current study.

Methods

Between 1997 and 2003, laparoscopic fundoplication was performed in 56 handicapped children (mean age, 6 years), and gastrostomy was performed concurrently in 52. The main symptoms were emesis/hematemesis in 40 and respiratory symptoms, including repeated respiratory infection and distress, in 31.

Results

There were no severe postoperative complications or operative mortality. Emesis/hematemesis was controlled adequately in those without recurrence. Respiratory symptoms were controlled unsuccessfully in 16 patients (52%), 8 of whom required further respiratory care including nasal airway tube, tracheostomy, and laryngotracheal separation. Recurrence of GER disease occurred in 10 patients, 7 of whom underwent a second Nissen fundoplication successfully. Thirteen died within the median follow-up period of 14 months.

Conclusions

Laparoscopic fundoplication is effective in controlling emesis/hematemesis, but its efficacy is limited in terms of respiratory problems in handicapped children. Further refinements in diagnostic and treatment strategies are mandatory to improve the quality of life in such patients.  相似文献   
87.

Purpose

To document long-term morphological changes of Chiari type II malformation (CM-II) following closure of spina bifida manifesta (SBM).

Methods

We retrospectively evaluated postnatal magnetic resonance images of the CM-II and posterior fossa (PF) in 28 consecutive cases. We measured changes in vertebral level and length of the cerebellar peg (CP), cerebrospinal fluid (CSF) spaces anterior and posterior to the cerebrospinal junction, PF area, and the anteroposterior diameters of the foramen magnum (FM) and C1 vertebra. We examined the morphological differences between the cases with and without ventriculoperitoneal (VP) shunting and derived predicted means by nonlinear mixed-effect modeling.

Results

At birth, there were significant differences in CP length, PF area, and FM and C1 diameters between those who underwent VP shunting and those who did not. In cases with a CP below C1, VP shunting was required in every case but one. In those with visible CSF space at birth, VP shunts were not required. In 17 of 18 cases with a CP below C1, the vertebral level ascended by mean two vertebral levels (range 0–5 levels) within 4–6 months of delivery. In the remaining case, slowly progressive hydrocephalus and delayed CP descent required VP shunting at 8 months. Predicted mean CP length and FM and C1 diameters were greater in those who underwent VP shunting, but there was no difference in predicted mean PF area.

Conclusion

The morphology of CM-II and the presence of hydrocephalus influence each other in children who have undergone postnatal SBM repair.
  相似文献   
88.
We report two cases of osteoblastoma, one of them an unusual case in a 32-year-old woman in whom a maxillary tumor was confidently diagnosed as an osteoblastoma at the time of primary excision and subsequently transformed into an osteosarcoma 7 years after the onset of clinical symptoms. The other patient developed osteosarcoma arising in the maxilla, which was diagnosed 3 years after the primary excision and is very suggestive of malignant transformation in osteoblastoma. We present the radiological features, including computed tomographic and magnetic resonance imaging studies, of this unusual event of transformed tumor and compare imaging features of benign and dedifferentiated counterparts of this rare tumor complex.Members of the Group for the Image Diagnosis of Craniofacial Disorders  相似文献   
89.
Summary The gene encoding the specific glycosyltransferases which catalyze the conversion of the H antigen to A or B antigens shows a slight but distinct variation in its allelic nucleotide sequence and can be divided into 6 genotypes when digested with specific restriction enzymes. We extracted DNA from formalin-fixed, paraffin-embedded tissues using SDS/proteinase K treatment followed by phenol/chloroform extraction. The sequence of nucleotides for the A, B and O genes was amplified by the polymerase chain reaction (PCR). DNA fragments of 128 by and 200 by could be amplified in the second round of PCR, using an aliquot of the first round PCR product as template. Degraded DNA from paraffin blocks stored for up to 10.7 years could be successfully typed. The ABO genotype was deduced from the digestion patterns with an appropriate combination of restriction enzymes and was compatible with the phenotype obtained from the blood sample.  相似文献   
90.
Objectives: To assess the impact of baseline lower urinary tract symptoms on postoperative urinary morbidity in patients being treated for prostate cancer with 125‐I permanent prostate brachytherapy. Methods: A total of 104 prostate cancer patients were enrolled in this study. Their urinary morbidity was followed up using the International Prostate Symptom Score and Expanded Prostate Cancer Index Composite for 12 months or more after permanent prostate brachytherapy. Patients were classified into two groups based on their baseline International Prostate Symptom Score: the low International Prostate Symptom Score group (score ≤ 7) and the high International Prostate Symptom Score group (score ≥ 8). Urinary morbidity was estimated in each group based on the results of the International Prostate Symptom Score and Expanded Prostate Cancer Index Composite measured before permanent prostate brachytherapy, and at 1, 3, 6, 9 and 12 months after the end of all radiation therapy. Results: The overall mean total International Prostate Symptom Score, International Prostate Symptom Score quality of life score, and urinary‐related scores for Expanded Prostate Cancer Index Composite were significantly worse at 1 month after the end of treatment, but they improved gradually after the treatment and recovered to the baseline level within 12 months. Even in the high‐International Prostate Symptom Score group, the International Prostate Symptom Score and International Prostate Symptom Score Quality of Life score were significantly worse at 1–3 months after permanent prostate brachytherapy, and then recovered to the baseline level without prolongation. Although the urination‐related Expanded Prostate Cancer Index Composite score in the high‐International Prostate Symptom Score group was significantly worse at 1 month after permanent prostate brachytherapy in comparison with that in the low‐International Prostate Symptom Score group, it recovered to the baseline level without prolongation. Conclusions: The present findings suggest that the presence of lower urinary tract symptoms before implantation does not prolong urinary morbidity after permanent prostate brachytherapy.  相似文献   
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