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81.
BACKGROUND: Few published data are available regarding perioperative blood usage in lung transplantation. STUDY DESIGN AND METHODS: The medical records of all patients undergoing lung transplantation at a university medical center in 1994 and 1995 were reviewed. RESULTS: Ninety patients underwent lung transplantation during this period. Six patients were excluded: two received a living related-donor lung, three underwent retransplantation and one underwent concomitant repair of a tetralogy of Fallot. Of the 84 evaluable patients, 59 underwent single lung transplantation and 25 double lung transplantation. Double-lung recipients used more red cells (6.4 vs. 1.7 units, p = 0.0002) and were more likely to receive red cells, platelets, plasma, or any component (92 vs. 32%, p< or =0.0001) than were single-lung recipients. Double- lung recipients were more likely to require cardiopulmonary bypass (40 vs. 12%, p = 0.003), and cardiopulmonary bypass was associated with greater transfusion requirements (p< or =0.0001). However, among patients requiring cardiopulmonary bypass, blood use did not differ between those undergoing double lung transplantation and those undergoing single lung transplantation. In the subset of patients not requiring cardiopulmonary bypass, double-lung recipients received more red cells (4.5 vs. 0.7 units, p< or =0.0001) and more plasma (2.0 vs. 0.2 units, p = 0.006). CONCLUSION: Double-lung recipients require more perioperative transfusions than single-lung recipients. The greater transfusion requirement is due to the more frequent need for cardiopulmonary bypass as well as the greater complexity of the procedure. These data are useful for developing surgical blood ordering guidelines for lung transplantation.  相似文献   
82.
The detection of elevated cholesterol levels in more than 60% of adults in the United States has prompted widespread mass cholesterol screening to identify this modifiable risk factor for coronary disease. As nurses begin to assume more responsibility for these screenings, additional training in this area may be warranted. National screening guidelines are reviewed in reference to measurement issues, including potential sources of variation in cholesterol measurement, precision and accuracy testing, and the importance of rigorous quality control measures and staff training programs, all of which ensure the standardization of cholesterol measurements. The role of nurses in cholesterol screening is presented.  相似文献   
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The role of basal forebrain-derived cholinergic afferents in the development of neocortex was studied in postnatal rats. Newborn rat pups received intraventricular injections of 192 IgG-saporin. Following survival periods ranging from 2 days to 6 months, the brains were processed to document the cholinergic lesion and to examine morphological consequences. Immunocytochemistry for choline acetyltransferase (ChAT) and in situ hybridization for ChAT mRNA demonstrate a loss of approximately 75% of the cholinergic neurons in the medial septum and nucleus of the diagonal band of Broca in the basal forebrain. In situ hybridization for glutamic acid decarboxylase mRNA reveals no loss of basal forebrain GABAergic neurons. Acetylcholinesterase histochemistry demonstrates a marked reduction of the cholinergic axons in neocortex. Cholinergic axons are reduced throughout the cortical layers; this reduction is more marked in medial than in lateral cortical areas. The thickness of neocortex is reduced by approximately 10%. Retrograde labeling of layer V cortico-collicular pyramidal cells reveals a reduction in cell body size and also a reduction in numbers of branches of apical dendrites. Spine densities on apical dendrites are reduced by approximately 20-25% in 192 IgG- saporin-treated cases; no change was detected in number of spines on basal dendrites. These results indicate a developmental or maintenance role for cholinergic afferents to cerebral cortical neurons.   相似文献   
85.
S D Anderson  R E Schoeffel    M Finney 《Thorax》1983,38(4):284-291
The airway response to the inhalation of ultrasonically nebulised distilled water was determined in 55 asthmatic patients and 16 normal subjects. We calculated the dose of water required to induce a 20% reduction (PD20) in forced expiratory volume in one second (FEV1) by measuring the output of the nebuliser and the volume ventilated by each subject. Forty-eight of the asthmatic patients had a PD20 of 9 ml or less but three patients required as much as 24 ml. A PD20 was not recorded in the normal subjects and the challenge was stopped after 33 ml. In 12 patients the challenge was repeated within six months and the airway response was shown to be reproducible at equivalent doses of water. In a separate group of 11 patients there was, however, a highly significant reduction in the percentage fall in FEV1 when equivalent doses of water were given on two occasions 40 minutes apart. When the temperature of the inhaled water was increased from 22 degrees C to 36 degrees C eight of 10 patients had a similar change in FEV1 with equivalent doses of water. The airways obstruction induced by the inhalation of water was readily reversed with salbutamol administered by aerosol. In some patients a challenge with water or 3.6% saline was repeated after pretreatment with sodium cromoglycate, atropine methonitrate, and verapamil hydrochloride, all given as aerosols. The airway response to the equivalent dose of water or saline was significantly reduced after treatment with sodium cromoglycate but not atropine or verapamil.  相似文献   
86.
A procedure for combining evidence from different biological assays is shown to be equivalent both to generalized least-squares and to maximum-likelihood estimation. By appropriate nesting of hypotheses, the likelihood function can be used to test the agreement between the assays and to obtain probability limits for the combined estimate of potency. The properties of these limits are examined, with particular reference to the situation, unusual but not impossible in practice, in which the values of relative potency that they define consist of several disjoint segments instead of a single interval. The connection with general theory of estimating linear functional relations is pointed out.  相似文献   
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PURPOSE: To characterize their information needs, we examined the main topics of inquiry and discussion (subjects of interaction, SOI) of calls made by family and friends of cancer patients to the National Cancer Institute's Cancer Information Service's (CIS) 1-800-4-CANCER telephone information service and summarized differences by sociodemographic characteristics. DESIGN AND ANALYSIS: Data from 26 789 family or friends of cancer patients calling the CIS between September 2002 and August 2003 were analyzed. Frequencies, chi(2)'s, and logistic regressions were conducted to ascertain sample characteristics and sociodemographic correlates of each SOI. RESULTS AND CONCLUSIONS: The greatest proportion of calls concerned specific treatment information (54.9%) and general cancer site information (36.9%). Calls about specific treatment information were more likely among Asians, Hawaiian Natives, and Pacific Islanders (OR = 1.23, 1.04-1.45), and those with higher education (OR = 1.21, 1.18-1.25). As age increased, the odds of calls about specific treatment information also increased (OR = 1.05, 1.03-1.07). Females (OR = 0.78, 0.72-0.84), Hispanics (OR = 0.77, 0.67-0.89), African-Americans (OR = 0.68, 0.61-0.76), and American-Indians and Alaskan Natives (OR = 0.74, 0.58-0.93) were less likely to inquire about specific treatment information. Inquiries about general cancer site information were more likely among females (OR = 1.14, 1.06-1.23) and less likely among younger callers (OR = 0.95, 0.93-0.97) and African-Americans (OR = 0.87, 0.78-0.98). Differences in inquiries made by sociodemographic subgroups can inform the CIS' and other cancer-related organizations' efforts to develop and disseminate cancer information for family and friends of cancer patients.  相似文献   
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