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21.

Background

Cavernous malformations (CMs) of the central nervous system (CNS) are angiographically occult vascular lesions that affect approximately 0.5 % of the general population, and one quarter of all CMs occurs in children.

Methods

We retrospectively analyzed demographic, clinical, radiological, management, and follow-up data of 36 pediatric patients with CMs from a single institution.

Results

The mean age of the children at first presentation and at operation was 8.7 and 9.6 years, respectively. However, a bimodal age distribution was found with peak under 4 years and above 12 years. Seizure was the most common single presenting symptom (38.9 %), and 61.1 % of patients had at least one seizure before the admission. Focal neurological deficits (410.7 %), intracranial hypertension (27.8 %), and headache (2.8 %) were the other manifestations. Acute/subacute hemorrhage was evident at presentation in 63.9 %. The patients under 6 years of age were found to have significantly more giant cavernomas (69 vs 20 %; p?=?0.011), and more overt hemorrhages (81 vs 47 %; p?=?0.065) at diagnosis than those patients above 12 years. Surgery was performed in 31 patients (32 CMs), with 26 total and 6 incomplete resections. Mean follow-up duration was 6.9?±?4.1 years. Of all patients, 63.8 % had excellent and 30.5 % had good clinical outcomes, and also 90.9 % of the epileptic patients were seizure-free (Engel Class I) at the last follow-up.

Conclusions

Younger children tend to harbor larger CMs and present with hemorrhage more frequently than older ones. Microsurgical resection should be the treatment of choice in symptomatic and accessible CMs.  相似文献   
22.
23.

Introduction

Vertical root fracture is a common finding in endodontically treated teeth, notably oval roots. The aim of the present study was to determine the effect of instrumentation kinematics and the material of instrument construction of single-file systems on dentin walls and fracture resistance of oval roots.

Methods

Sixty-five roots with oval canals were allocated into a control group (n = 5) and 3 experimental groups of 20 roots each. Group WO was instrumented with the WaveOne primary file (Dentsply Maillefer, Baillagues, Switzerland), group PT-Rec was prepared with F2 ProTaper files (Dentsply Maillefer, Baillagues, Switzerland) used in a reciprocating motion, and group PT-Rot was prepared with F2 ProTaper files used in a rotation motion. For crack evaluation, half of the samples (n = 30) were embedded in acrylic resin, and the blocks were sectioned at 3, 6, and 9 mm from the apex. The sections were examined under a stereomicroscope and scored for crack presence. The other half of the specimens (n = 30) were obturated using lateral condensation of gutta-percha and AdSeal sealer (Meta Biomed Co, Ltd, Chungbuk, Korea). The specimens were then subjected to a load of 1 mm/min to determine the force required to fracture the roots.

Results

WaveOne instruments induced the least amount of cracks and exhibited greatest resistance to fracture compared with ProTaper F2 files whether used in reciprocating or rotating motions.

Conclusions

The alloy from which the material is manufactured is a more important factor determining the dentin damaging potential of single-file instruments than the motion of instrumentation.  相似文献   
24.
Neonatal resuscitation is a coordinated, team-based series of timed sequential steps that focuses on a transitional physiology to improve perinatal and neonatal outcomes. The practice of neonatal resuscitation has evolved over time and continues to be shaped by emerging evidence as well as key opinions. We present the revised Neonatal Resuscitation Guidelines for Singapore 2021. The recommendations from the International Liaison Committee on Resuscitation Neonatal Task Force Consensus on Science and Treatment Recommendations (2020) and guidelines from the American Heart Association and European Resuscitation Council were compared with existing guidelines. The recommendations of the Neonatal Subgroup of the Singapore Resuscitation and First Aid Council were derived after the work group discussed and appraised the current available evidence and their applicability to local clinical practice.  相似文献   
25.
26.
目的了解新疆贫困县医务人员对专业技术的熟悉度和培训需求,为提高农村医务人员的服务能力提出相应对策与建议。方法采用随机分层抽样方法,在新疆36个贫困县中随机抽取6个贫困县中6个县医院、18个乡卫生院和54个村卫生室的医务人员作为研究对象,采用现场问卷调查,用构成比对医务人员基本情况、医务人员专业熟悉度及培训需求进行统计描述。结果被调查的医务人员学历、职称偏低,从事专业科目较集中;医生对专业技术熟悉排在前3位的是内科、外科和妇科;护士对专业技术熟悉排在前3位的是临床护理、急救护理和慢性病的临床护理;医务人员对公共卫生相关专业的熟悉程度均低;同时对各最熟悉的基本学科的培训需求度高。结论根据贫困县实际发展情况,加强对基本医疗和公共卫生专业知识的培训,增加检验及影像等医技人员,并且加强乡镇卫生院全科医生的在职培训,从而全面提高医疗机构服务能力,以满足新疆农村贫困地区的基本医疗和公共卫生服务需求。  相似文献   
27.

Purpose

To increase the knowledge of central nervous system (CNS) imaging features in deficiency of adenosine deaminase 2 (DADA2) by examining magnetic resonance imaging (MRI) studies of a relatively large number of patients.

Methods

We retrospectively examined neuroimages of 12 patients (7 male, 5 female) diagnosed with DADA2. The mean age of the patients at the time of initial brain MRI was 16.7 ± 10.2 years. Seven patients (58.3%) fulfilled the classification criteria of polyarteritis nodosa. Brain MRI studies were assessed with respect to findings of ischemia, intracranial hemorrhages, focal parenchymal signal abnormalities, cerebral/cerebellar volume loss, and abnormal contrast enhancement. Angiographic studies of 7 patients were evaluated for the signs of vasculitis.

Results

The most frequent finding was acute and/or chronic lacunar ischemic lesions in the brainstem and/or deep gray matter (n = 9, 75%). Six patients (50%) revealed MRI findings compatible with recurrent ischemic attacks. Small nodular contrast enhancement (n = 2, 16.6%), acute putaminal hemorrhage (n = 1, 8.3%) and findings compatible with posterior reversible encephalopathy syndrome (n = 1, 8.3%) were also detected. Slight-to-moderate diffuse cerebral and/or cerebellar volume loss (n = 7, 58.3%), decreased T1 signal of the bone marrow (n = 6, 50%) and optic atrophy (n = 1, 8.3%) were the other findings on brain MRI. The only abnormal angiographic finding was reduced caliber of the right distal posterior cerebral artery in MRA of a patient (14.6%).

Conclusion

DADA2 should be included in the differential diagnosis of young patients presenting with ischemic and/or hemorrhagic lesions located in the brainstem and deep gray matter, especially if they have a family history or additional systemic abnormalities.  相似文献   
28.
29.
PURPOSE: To evaluate the efficacy of preemptive analgesia in surgical repair of retinal detachment (RD) using scleral buckle and cryopexy under general anesthesia. METHODS: Thirty patients who were scheduled for rhegmatogenous RD surgical repair using scleral buckle and cryopexy and who were American Society of Anesthesiologists physical status I, II, or III were included in this study. The patients were randomly divided into two equal groups. The surgery was done under general anesthesia in both groups, but in Group 2, sub-Tenon anesthesia was given as preemptive analgesia after induction anesthesia and before start of surgery. Both groups were statistically comparable as regards patient age and weight and duration of anesthesia and surgery. RESULTS: The incidences of intraoperative oculocardiac reflex and postoperative vomiting were significantly lower in Group 2 compared with Group 1 (P < 0.001 and 0.0113, respectively). The time of first postoperative analgesic dose was significantly shorter in Group 1 (46.67 +/- 18.84 minutes) compared with Group 2 (162.67 +/- 29.391 minutes) (P < 0.001). The total analgesic consumption per 24 hours was significantly higher in Group 1 compared with Group 2 (P < 0.001). The time of discharge from the hospital was significantly shorter in Group 2 (8.8 +/- 2.704 hours) compared with Group 1 (12.4 +/- 3.481 hours) (P = 0.0018). CONCLUSION: The use of sub-Tenon block as preemptive analgesia after induction of general anesthesia and before the start of rhegmatogenous RD surgical repair was effective in reducing postoperative pain and analgesic requirements compared with an unblocked group. The use of sub-Tenon block was also effective in reducing intraoperative incidence of oculocardiac reflex and postoperative incidence of vomiting.  相似文献   
30.
Between May and October 2000, the Regional Health Office of Kolda Region in the south of Senegal, West Africa, reported an epidemic of an unknown illness characterized by thoracic pain, dyspnea and edemas of limb and face. The epidemic covered a radius of approximately 40 km (24 miles) between the districts of Kolda and Sedhiou in Kolda Region. Cases were mostly men whose age ranged between 12 and 60 years old. Investigation revealed that they had been exposed to pesticides distributed by the government to groundnut farmers. The signs and symptoms suggested intoxication with carbamates, carbofurans, and possibly thiram, contained in the pesticides distributed with the groundnut seeds. Government distribution created an excessive use of pesticides in the farms, and consequently an overexposure of the subjects who handled the seeders, especially young males but also a small proportion of women who worked in the groundnut fields. Many of these subjects, not accustomed to handle pesticides, came to overestimate the quantity of product to fill the seeder. It should be noted that the policy of distribution of pesticides in Senegal, which presents risk of poisoning, was not systematically accompanied by sufficient information on the danger of the products and of certain precautions that should be taken during their use.  相似文献   
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