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81.
This paper documents the type, frequency and duration of complications associated with regional anaesthesia of the maxillary nerve via the greater palatine canal in a series of 101 patients treated in the Oral Surgery Department, United Dental Hospital of Sydney.  相似文献   
82.
Following Catastrophic Epilepsy Patients from Childhood to Adulthood   总被引:2,自引:0,他引:2  
Summary:  As patients with catastrophic epilepsies move from childhood to adulthood, evolving and innovative therapeutic regimens are often required. However, the goal of providing the best quality of life while minimizing both seizures and side effects remains the same. Clinicians can develop appropriate care plans by being aware of patients' changing needs. Clinical symptoms of the catastrophic epilepsies may change over time; by understanding the natural history of a patient's condition, clinicians can help ease the transition from childhood to adulthood. Additionally, as children with catastrophic epilepsies become adults, medical issues (e.g., medication side effects, tolerance, and dependence) and nonmedical issues (e.g., guardian/caretaker issue, group home applications, and respite care options) must be considered when developing strategies for patient care. Regular assessment of patients, the development of emergency plans, and maintenance of consistency in the delivery of care are also important issues to consider. Finally, a multidisciplinary care plan that incorporates resources from health-care practitioners, social service professionals, and community agencies can be valuable in optimizing treatment for patients with catastrophic epilepsies.  相似文献   
83.
The spleen, whether anatomically and physiologically normal or diseased, may significantly worsen the clinical picture in a variety of medical disorders. However, splenectomy should be undertaken only after a careful balancing of the short- and long-term risks and potential benefits to the patient, which are discussed in the following review.  相似文献   
84.
A 50-year-old patient with breast cancer was about to withdraw from her adjuvant chemotherapy regimen because of a long-standing phobia about being injected, which had been compounded by anxieties that were associated with the severe side-effects of adjuvant chemotherapy. She experienced a conditioned nausea response to hospital and medical situations. A psychological programme that incorporated relaxation training, systematic desensitization by way of the patient's visual imagination and videotape modelling, allowed her to complete the course of chemotherapy and to feel less anxious in hospital and medical settings.  相似文献   
85.
86.
This study was to evaluate the effects of cigarette smoke constituents upon type II pneumocyte surfactant production in vitro, and how vitamins A and E may alter the response. Freshly isolated type II pneumocytes from Sprague–Dawley rats were incubated 20 h in medium with fetal bovine serum that was or was not treated with cigarette smoke. The number of adherent cells was inversely related to the dose of smoke or benzo(a)pyrene. Despite the decreased number of treated cells, the total amount of surfactant per culture well was unchanged, whereas surfactant production per cell was significantly increased (P < 0.05). Vitamin A concentration was significantly (P < 0.05) lower in the smoke-treated serum compared with untreated serum. When vitamin A or E was added to the cigarette smoke-treated serum, cell adherence and surfactant production returned to control values. In conclusion, cigarette smoke constituents or benzo(a)pyrene alone decreased the number of adherent type II pneumocytes, but did not alter surfactant amounts because of an increased production of surfactant per cell. Type II pneumocytes seem to adjust surfactant production dependent upon the number of type II pneumocytes to produce it and vitamin A or E enhance cell attachment in the presence of the smoke toxins.  相似文献   
87.
Alterations in T wave morphology have been quantitated in seven open chest anesthetized dogs by simultaneous recording of electrograms from 10 epicardial sites across the anterior left ventricular wall under basal conditions, following left sympathetic stimulation (LSS) at 2, 4, 8, 12, and 16 Hz and during noradrenaline infusions (NAI) of 0.125, 0.25, 0.50, and 1.0 micrograms/kg/min. Overdrive atrial pacing at 175 beats/min was employed and rate of rise of left ventricular pressure (dP/dt) monitored. Linear log dose-response relationships were found between both peak T amplitude and left ventricular dP/dt for NAI between 0.125 and 0.50 micrograms/kg/min (peak T wave amplitude 4.0 +/- 0.9 to 1.4 +/- 0.7 mV). Following LSS, T wave amplitude responses were highly variable both between animals and between electrode sites in individual studies. A linear log dose-response relationship was found at stimulation frequencies between 8 and 16 Hz (T amplitude 3.9 +/- 1.4 to 1.8 +/- 1.2 mV). Changes in QT interval were minor and inconsistent. It is concluded that changes in peak T wave amplitude may provide a useful index of regional myocardial sympathetic responsiveness following NAI, but are more variable following LSS.  相似文献   
88.
First-line therapy for hepatitis C virus (HCV) infection comprises interferon-alpha (IFN-alpha) and ribavirin for 6 or 12 months. Mild complications of therapy are common, but more serious complications are rare. Three patients with chronic HCV infection, acquired through injecting drug use, developed idiopathic facial paralysis (Bell's palsy) during therapy, with spontaneous resolution after withdrawal of treatment. Large-scale cohort studies reveal that IFNs are associated rarely with neurologic complications, and only one previous report has linked IFN-alpha therapy and Bell's palsy. We postulate that IFN-alpha therapy led to a breakdown of peripheral tolerance to myelin sheath antigens, leading to neuropathy, just as IFN-alpha therapy can cause autoimmune thyroiditis through breakdown of tolerance to native thyroid antigens.  相似文献   
89.
The carcinogenic effects of radiation have been demonstrated at high dose levels. At low dose levels, such as those encountered in medical diagnosis, the magnitude of the effect is more difficult to quantify. Three reasons for this difficulty are (1) the effects in human populations are small compared with the natural incidence of cancer in the populations; (2) it is difficult to transfer results obtained in animal studies to the human experience; and (3) the effects of latency period and plateau increase the complexity of population studies. In spite of these difficulties, epidemiologic studies of human populations exposed to low levels of radiation still play a valuable role in the determination of radiation carcinogenecity. They serve to provide upper estimates of risk and to rule out the appearance of new effects that may be masked by the effects of high doses. While there is evidence for mutagenic effects of radiation in experimental animals, no conclusive human data exist at the present. It is not possible to rule out the presence of genetic effects of radiation in humans, however, because many problems exist with regard to the epidemiologic detection of small effects when the natural incidence is relatively large. In animals, subtle effects (eg, a decrease in the probability of survival from egg to adult) may occur with greater frequency than more dramatic disorders in irradiated populations. However, these types of genetic abnormalities are difficult to quantitate. Current risk estimates are based primarily upon data pertaining to dominant mutations in rodents. Some specific locus studies also permit identification of recessive mutation rates. The embryo and fetus are considered to be at greater risk for adverse effects of radiation than is the adult. This sensitivity was predicted in 1906 by the law of Bergonie and Tribondeau and has been demonstrated in human and animal populations. At high dose levels (above 15 rem), the effects of radiation depend upon the gestational stage at which irradiation occurs. Prior to the second week, the predominant effect is preimplantation death, while during the period of major organogenesis (second to sixth week), growth retardation and CNS abnormalities may be produced. These effects have not been demonstrated with a high degree of statistical significance at low dose levels (below 15 rem) and are not considered to present a serious hazard for patients undergoing radiologic exams.  相似文献   
90.
All the health visitors in the north of England, and more than half the general practitioners, were sent questionnaires about the primary health care of children. More than 90% of the health visitors responded. Most of them took part in developmental screening and considered it primarily their responsibility; some conducted developmental or well baby clinics with no other professionals present. Clinics run by health authorities often occupied several hours per week, and were more frequently attended by health visitors than clinics run by general practitioners. Almost all the health visitors' remaining time was spent in attached practices, despite the fact that more than half said they had neither office nor clinic space of their own on practice premises. A high proportion of time was spent on clerical work; more help with this could free the health visitor to provide better developmental care for all children.  相似文献   
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