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991.
992.
We report the case of a head-injured patient with spontaneous hyperventilation who had recurrent episodes of relative hypoventilation associated with increases in intracranial pressure. Detailed ventilatory studies were performed during the 2nd week after injury. Our findings in this patient prompted us to review the possible mechanisms underlying the observed changes. We suggest that spontaneous hyperventilation in head injury is secondary to a decrease in cortical inhibitory influences on respiratory control mechanisms and that the transient episodes of relative hypoventilation observed in our patient may reflect modified ventilatory responses dependent on the altered state of consciousness. (Neurosurgery, 5: 701--707, 1979).  相似文献   
993.
994.
Detection of breast disease in a family planning association clinic.   总被引:2,自引:0,他引:2  
The incidence and prevalence of disorders of the breast have been assessed in 13,456 women examined annually at a family planning clinic over 5 years. Screening for disorders of the breast was by clinical examination alone and abnormalities were detected in 1 of every 58 women attending the clinic and these were referred for hospital opinion: biopsy was required in 1 in 114. Only 12 cancers of the breast were detected and all of these in women over 35 years. It is suggested that the usual policy of examining the breasts of women taking oral contraceptive preparations should be restricted to those over 40 years.  相似文献   
995.
Lactation's contraceptive effect cannot be relied upon for more than 6 weeks postpartum, and ovulation often occurs in advance of the 1st postpartum menstrual period. Although breastfeeding mothers should adopt a contraceptive method, care must be taken to select a method that will not adversely affect the production and composition of breast milk. Of greatest concern is the effect of synthetic hormones transmitted via breast milk on the developing infant. Possible alternatives are the Billings ovulation detection natural family planning method, diaphragms and caps, IUDs, and sexual sterilization. While combined oral contraceptives (OCs) are contraindicated because of their harmful effects on the fat and protein composition of breast milk and on milk production, the progestogen-only OC does not appear to interfere with the quality of breast milk and less than 0.1% of the progestogen passes on to the infant. Depo-Provera, and other injectable progestogens, appear to be appropriate for breastfeeding women, although the 1st injection should be postponed until 6 weeks postpartum to reduce the likelihood of heavy bleeding. Under investigation is a nasal spray containing buserelin, a luteinizing hormone-releasing hormone agonist, that shows promise as a reliable, acceptable, and easily administered nonsteroidal contraceptive that does not interfere with lactation. A biodegradable buserelin implant, which would last as least 3 months, also is being developed and would be especially useful in developing countries where storage of a nasal spray might be problematic.  相似文献   
996.
M F Loudon 《JAMA》1988,259(7):1019-1020
  相似文献   
997.
Almost 6% of Britain's population are of black or minority ethnic origin. There is increasing recognition that the health needs of such groups are not adequately met within the current health care system. One factor in reducing health inequalities is for health professionals to become culturally aware in order to serve these communities effectively. This literature review focuses on pre-registration nursing programmes that address cultural sensitivity as part of basic training. The studies were selected by a computerized search of a number of databases and a hand search of selected nursing journals. The papers were reviewed under the following headings: setting, programme design, conceptual framework, curricula content, student assessment, and course evaluation. The programmes presented were undertaken predominantly in the USA. Either few programmes exist in the UK, or the programme details have not been published. Although, in the UK, cultural sensitivity training appears in its infancy, there are positive signs of change.  相似文献   
998.
Abstract:   When a patient presents with pain in the different regions of the spine, the clinician executes a region-appropriate basic examination that includes appropriate historical cues and specific physical examination tests that can be used to identify red flags. The clinical tests include a specific examination of the sensory and motor systems. Test outcomes are best interpreted in context with the entire examination profile, where the sensitivity and specificity of these tests can influence their utility in uncovering red flags. These red flags can be categorized based on the nature and severity or the specific elements of the patient's presentation. Many general red flags can be observed in any region of the spine, while specific red flags must be categorized and discussed for each spinal region. This categorization can guide the clinician in the direction of management, whether that management is aimed at redirecting the patient's care to another specialist, reconsidering the presentation and observing for clusters of findings that may suggest red flags, or managing the patient within the clinician's specialty in context with the severity of the patient's presentation.  相似文献   
999.
BACKGROUND: In 1993, the American Association of Blood Banks (AABB) received reports of severe hypotensive reactions associated with platelet transfusions. The question arose as to whether these reports were indicative of a previously uncharacterized platelet transfusion reaction. STUDY DESIGN AND METHODS: To further characterize these reactions, the AABB Transfusion Practices Committee developed a series of three questionnaires. The initial questionnaire was sent to all AABB institutional members; the two subsequent questionnaires were sent to those institutions reporting severe and/or unusual platelet transfusion reactions. This report focuses on the 24 responses to the third and most detailed questionnaire, which specifically addressed reactions that were characterized by hypotension and/or unexplained respiratory failure. RESULTS: Of the 24 detailed responses received, 4 were not considered to represent unusual reactions to platelet transfusion, 3 described reactions consistent with a (presumably unrecognized) diagnosis of transfusion-related acute lung injury, and 17 described reactions that were primarily characterized by hypotension. The majority of the hypotensive reactions occurred within 1 hour of the beginning of the transfusion (88%), were associated with respiratory distress (82%), and resolved rapidly after cessation of the transfusion (82%). Eighty-eight percent of implicated components had been white cell reduced by filtration. CONCLUSION: The hypotensive platelet transfusion reactions that were described appear to represent a previously uncharacterized complication of platelet transfusion. However, the nature of the questionnaires used in this investigation does not allow the drawing of firm conclusions as to the frequency or the cause of these reactions.  相似文献   
1000.
BACKGROUND: Platelet utilization has steadily increased throughout the past three decades. At the same time, there has been very little study of the current transfusion practices. STUDY DESIGN AND METHODS: A survey was conducted of institutional members of the American Association of Blood Banks (hospitals) that were actively involved in the care of pediatric and/or adult hematology and/or oncology patients. Inquiries were made relating to the extent of prophylactic versus therapeutic use of platelets, criteria used for prophylactic transfusion of platelets and type, and dose of platelets used. Data were analyzed according to patient age and type of hospital. RESULTS: Of 786 responding hospitals, 630 (80.2%) provided sufficient data for analysis; 126 of that 630 provided care for pediatric patients. The majority (60.9%) of responding hospitals had a minimum of four hematologists and/or oncologists. Eighty-four percent of hospitals reported transfusing some apheresis platelets. The dose of platelet concentrates most frequently used for adults ranged from 6 to 10, with pools of 10 more commonly used in community hospitals. More than 70 percent of hospitals reported transfusing platelets primarily for prophylaxis: 60 percent of hospitals set the threshold platelet count for prophylactic platelet transfusion at 20,000 per microL, with approximately 20 percent each transfusing at higher and lower levels. A platelet count of 50,000 per microL was most frequently required for performance of a minor invasive procedure. CONCLUSION: The data from this study show that the majority of institutions use prophylactic platelet transfusion in both pediatric and adult hematology and/or oncology patients. However, there is considerable variation in platelet transfusion practice.  相似文献   
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