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101.
102.
Pneumoperitoneum is usually associated with gastrointestinal perforation or following surgical and endoscopic procedures. We report a rare case of spontaneously perforated pyometra presenting with generalised peritonitis and pneumoperitoneum. Perforation of the uterus is also unusual and often associated with the presence of an intrauterine device, a gravid uterus or malignancy. Our case illustrates the importance of clinical knowledge of acute and neoplastic gynaecological diseases, which are not uncommonly encountered by the general surgeon. Moreover, good appreciation of pelvic anatomy and close collaboration with gynaecology colleagues is essential as operative intervention is often required.  相似文献   
103.
The evolution of wireless communication technologies opened the way to the definition of innovative e-Health systems aimed at providing a continuous and remote support to patients and new instruments to improve the workflow of the medical personnel. Nowadays, pervasive healthcare systems are a major step in this regard. The safety-critical systems on one hand and their failure in communication (i.e. sending and receiving messages) in other hand may lead to disaster results in the systems. Moreover, the need for high quality services in such systems, and the access to various types of Quality of Services such as reliability in software development has been increasing in the past years. In this paper, firstly we extend the core meta-model of the previously designed style for designing the structures of such systems in order to reach a high level of reliability in messaging. Secondly, their configuration mechanisms in controlling the communicative errors will be modeled using graph transformation rules. Finally, the correctness of the model is analyzed by model checking techniques. The results of the analysis show its high reliability.  相似文献   
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106.
The introduction of the 2000 Guidelines for Cardiopulmonary Resuscitation emphasizes a new, evidence-based approach to the science of ventilation during cardiopulmonary resuscitation (CPR). New laboratory and clinical science underemphasizes the role of ventilation immediately after a dysrhythmic cardiac arrest (arrest primarily resulting from a cardiovascular event, such as ventricular defibrillation or asystole). However, the classic airway patency, breathing, and circulation (ABC) CPR sequence remains a fundamental factor for the immediate survival and neurologic outcome of patients after asphyxial cardiac arrest (cardiac arrest primarily resulting from respiratory arrest). The hidden danger of ventilation of the unprotected airway during cardiac arrest either by mouth-to-mouth or by mask can be minimized by applying ventilation techniques that decrease stomach gas insufflation. This goal can be achieved by decreasing peak inspiratory flow rate, increasing inspiratory time, and decreasing tidal volume to approximately 5 to 7 mL/kg, if oxygen is available. Laboratory and clinical evidence recently supported the important role of alternative airway devices to mask ventilation and endotracheal intubation in the chain of survival. In particular, the laryngeal mask airway and esophageal Combitube proved to be effective alternatives in providing oxygenation and ventilation to the patient in cardiac arrest in the prehospital arena in North America. Prompt recognition of supraglottic obstruction of the airway is fundamental for the management of patients in cardiac arrest when ventilation and oxygenation cannot be provided by conventional methods. "Minimally invasive" cricothyroidotomy devices are now available for the professional health care provider who is not proficient or comfortable with performing an emergency surgical tracheotomy or cricothyroidotomy. Finally, a recent device that affects the relative influence of positive pressure ventilation on the hemodynamics during cardiac arrest has been introduced, the inspiratory impedance threshold valve, with the goal of maximizing coronary and cerebral perfusion while performing CPR. Although the role of this alternative ventilatory methodology in CPR is rapidly being established, we cannot overemphasize the need for proper training to minimize complications and maximize the efficacy of these new devices.  相似文献   
107.
SUMMARY The antianginal efficacy of a fixed combination of atenolol (50 mg) and nifedipine (20 mg) was compared with nifedipine (20 mg) alone; 102 patients experiencing three or more anginal attacks on their current monotherapy received each treatment twice daily for 3 weeks in a randomised, double-blind crossover trial. Both treatments reduced the weekly number of angina attacks compared with existing therapy; treatment with the fixed combination resulted in significantly fewer angina attacks per week than treatment with nifedipine alone. Also, when the fixed combination treatment followed the period of nifedipine therapy a further decrease in weekly angina attack rate was apparent. Comparison of individual patient response to each treatment showed that twice as many patients reported lower attack rates while on the fixed combination: 6 patients were withdrawn while receiving fixed combination compared with 10 patients on nifedipine alone. However, the incidence of commonly reported complaints was similar with both treatments.  相似文献   
108.
Hematogones: a multiparameter analysis of bone marrow precursor cells   总被引:1,自引:1,他引:1  
Morphologically distinct lymphoid cells with homogeneous, condensed chromatin and scant cytoplasm can be observed in large numbers in the bone marrow of children with a variety of hematologic and nonhematologic disorders. In some patients, these cells may account for greater than 50% of the bone marrow cells, creating a picture that can be confused with acute lymphoblastic leukemia (ALL) or metastatic tumor. Although originally called hematogones (HGs), a variety of other names have been proposed for these unique cells. The clinical significance of expanded HGs has not been resolved, and the biologic features of these cells are incompletely described. In this study, we correlate the clinical, morphologic, cytochemical, flow cytometric, molecular, and cytogenetic properties of bone marrow samples from 12 children with substantial numbers of HGs (range 8% to 55% of bone marrow cells). Diagnoses in these patients included anemia, four; neutropenia, one; anemia and neutropenia, one; idiopathic thrombocytopenic purpura, two; retinoblastoma, two; Ewing's sarcoma, one; and germ cell tumor, one. Flow cytometric analyses of bone marrow cells demonstrated a spectrum extending from early B-cell precursors (CD10+, CD19+, TdT+, HLA-Dr+) to mature surface immunoglobulin-bearing B cells in these patients, corroborating our morphologic impression of HGs, intermediate forms, and mature lymphocytes. DNA content was normal, and no clonal abnormality was identified by either cytogenetic or immunoglobulin and T-cell receptor (TCR) gene rearrangement studies. Follow-up ranged from 3 months to 3 years. None of the patients has developed acute leukemia or bone marrow involvement by solid tumor. The possible role of HGs in immune recovery and hematopoiesis is presented.  相似文献   
109.

OBJECTIVE:

To describe services received by preschool children diagnosed with autism spectrum disorder (ASD) during the five-year period following their diagnosis.

METHOD:

An inception cohort of preschoolers diagnosed with ASD from Halifax (Nova Scotia), Montreal (Quebec), Hamilton (Ontario), Edmonton (Alberta) and Vancouver (British Columbia) were invited to participate. Parents/caregivers (n=414) described the services provided to their children at four time points: baseline (T1; within four months of diagnosis; mean age three years); six months later (T2); 12 months later (T3); and at school entry (T4). Data were first coded into 11 service types and subsequently combined into four broader categories (no services, behavioural, developmental and general) for analysis.

RESULTS:

More than 80% of children at T1, and almost 95% at T4 received some type of service, with a significant number receiving >1 type of service at each assessment point. At T1, the most common service was developmental (eg, speech-language therapy). Subsequently, the most common services were a combination of behavioural and developmental (eg, intensive therapy based on applied behaviour analysis and speech-language therapy). Service provision varied across provinces and over time.

DISCUSSION:

Although most preschool children with ASD residing in urban centres were able to access specialized services shortly after diagnosis, marked variation in services across provinces remains a concern.  相似文献   
110.
Human immunodeficiency virus (HIV) infection associated aneurysmal vasculopathy is a rare complication of HIV infection affecting the pediatric and adult population. We present a case of a 7-year-old male child known to have a congenitally acquired HIV infection presenting with a ruptured left distal internal carotid artery fusiform aneurysm that was diagnosed on MRI scans 6 months prior to his presentation. He underwent craniotomy and successful aneurysm reconstruction. He had uncomplicated postoperative course and experienced a good recovery. This case is among the few reported pediatric cases of HIV-associated cerebral arteriopathy to undergo surgery. We also reviewed the relevant literature of this rare condition.Neurological involvement frequently complicates the course of human immunodeficiency virus (HIV) infection in both pediatrics and adults.1 Cerebrovascular complications are rarely encountered in these setting and are attributed either, to the primary HIV infection or secondary complications of immunodeficiency.2,3 The incidence of cerebrovascular events in pediatric patients with HIV infection is estimated to be 3.4 cases per 10000 person-years.4 Human immunodeficiency virus–associated arteriopathy encompasses several forms of arterial diseases occurring in the absence of any cause other than HIV infection. The HIV–associated aneurysmal arteriopathy is a rare cerebrovascular complication of acquired immune deficiency syndrome (AIDS) and has been the subject of several case reports and case series involving children, and more recently adults, with AIDS.2,3,5-10 This aneurysmal arteriopathy is characterized by multiple, diffused aneurysmal dilatations confined to the major arteries of the circle of Willis.1,11 The mechanism by which HIV results in CNS arterial damage is still not clearly understood.2 Most patients with this condition present with cognitive changes and motor deficits associated with infarction or hemorrhage.12 Our objective in presenting this particular case is to report a documented de novo left fusiform carotid bifurcation aneurysm in a child with maternally acquired-HIV infection who presented with subarachnoid hemorrhage and underwent surgical clipping of the aneurysm.  相似文献   
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