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21.
This article investigates the relationship between perceptions of equity, occupational stress and employee commitment in a health care setting. Significant relationships were found among these variables and implications for the health care field are discussed.  相似文献   
22.
To establish current national clinical practice in the care of patients with acute myocardial infarction (AMI), a questionnaire survey of 50 consultant physicians currently working in the Republic of Ireland was carried out. There were 45 (90%) respondants. 32/45 (71%) give thrombolysis in CCU only; 13/45 (29%) give thrombolysis in casualty also. Streptokinase (Stk) is the first choice thrombolytic agent for the majority. 14/45 (31%) use tPA for anterior AMI in patients under 60 years. Angiotensin converting enzyme (ACE) inhibitors are given by 34/45 (76%) to patients with evidence of left ventricular dysfunction. ACE inhibitors are neither used routinely nor are they prescribed in the first three days after the AMI by the majority of the physicians surveyed. Serum magnesium is checked routinely by 5/45 (11%) and intravenous magnesium is given routinely by 5/45 (11%). The percentage of AMI patients considered for angiography varied from 10–50%. Despite reports from randomised, controlled trials showing reduced mortality in patients given tPA (versus Stk), routine early ACE inhibition and intravenous magnesium post-AMI, most clinicians in Ireland use streptokinase, selective late ACE inhibition and no magnesium. The reasons for the dichotomy between the favourable results of randomised clinical trials and routine practice are speculative.  相似文献   
23.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关  相似文献   
24.
Technological advances in the field of medicine have resulted in the prolongation of lives that under ordinary conditions would have terminated. Such advances, though calling attention to the wonders of modern technology, are not without significant complications. The injudicious application of extraordinary procedures for extending life highlights problems that affect medical, social, and psychological as well as moral and ethical realms. The complexity of the problems has long since perplexed health/human service practitioners charged with effecting and/or assisting in the implementation of the critical life-death decisions on which this paper focuses.

A systematic strategy is outlined to guide human service providers in making decisions regarding the application or withholding of life-sustaining procedures. Emphasis is placed upon the integrity of self-determination as it relates to competency. Procedures for the incompetent patient are recommended.  相似文献   
25.
Hydrolysis of peptides within lumen of small intestine   总被引:2,自引:0,他引:2  
  相似文献   
26.
"Single" T = 1 isometric particles of Maize streak virus (MSV) have been isolated from infected maize leaves. Biochemical and genetic characterizations show that these particles contain subgenomic (sg) MSV DNA encapsidated by the MSV coat protein. The largest sg DNA is 1.56 kb, slightly larger than half genome size, although sg DNAs as small as 0.2 kb were also cloned. The sg DNAs are not infectious, and they do not appear to play a role in the pathogenicity of MSV. This is the first report of sg DNAs for MSV and, to our knowledge, the first time that encapsidated sg DNAs have been characterized at the sequence level for any geminivirus. These data will assist in our investigations into the role of genomic DNA in the formation of the unique geminate capsid architecture of the Geminiviridae.  相似文献   
27.
Parvovirus B19 is responsible for a spectrum of disease in humans. The usual bone marrow findings in acute parvovirus infections are marked erythroid hypoplasia and occasional giant erythroblasts. Intranuclear inclusions in developing erythroid precursors are rarely described in children or adults with parvovirus infection, although abundant intranuclear inclusions are commonly observed in the placenta and other tissues in infected fetuses. In this study, 8 patients are reported in whom the first evidence of parvovirus infection was the recognition of numerous intranuclear inclusions in erythroid precursors on bone marrow biopsy sections. Six of the 8 patients had documented immunodeficiencies; 4 had acquired immune deficiency syndrome (AIDS), and 2 were on chemotherapy. Five of 7 patients were negative for immunoglobulin G (IgG) antiparvovirus antibodies, including all 4 with AIDS. Unlike the typical pattern in parvovirus infection, the bone marrow was hypercellular in most of the patients, and erythroid precursors were usually increased with the entire spectrum of normoblast maturation represented; abundant intranuclear inclusions were observed similar to the finding in fetuses. The inclusions were variably eosinophilic and compressed the chromatin against the nuclear membrane. In situ hybridization showed parvovirus B19 DNA in numerous erythroid precursors in all cases. The findings of erythroid maturation and abundant viral inclusions in these immunocompromised patients is consistent with the hypothesis that failure to produce effective IgG parvovirus neutralizing antibodies may lead to persistent infection through viral tolerance that allows erythroid development of infected cells past the pronormoblast stage. Identification of parvovirus inclusions in marrow biopsies and subsequent confirmation of infection by in situ hybridization can be important in the assessment of anemia in immunodeficient patients because serological studies for parvovirus B19 are frequently negative.  相似文献   
28.
Variability of disease manifestations has been noted in patients with Lyme disease. A contributing factor to this variation may be the number of spirochetes present in infected patients. We evaluated clinical and laboratory findings for patients with erythema migrans with regard to the number of Borrelia burgdorferi organisms detected by quantitative PCR (qPCR) in 2-mm skin biopsy specimens. B. burgdorferi was detected in 80% (40 of 50) of the specimens tested; the mean number of spirochetes in these specimens ranged over 3 orders of magnitude (10 to 11,000 spirochetes per 2-mm biopsy specimen). Larger numbers of spirochetes were significantly associated with a shorter duration of the erythema migrans skin lesion (P = 0.020), smaller skin lesions (P = 0.020), and infection with a specific genotype of B. burgdorferi (P = 0.008) but not with the number or severity of symptoms. Skin culture positivity was significantly associated with skin lesions containing larger numbers of spirochetes (P = 0.019).  相似文献   
29.
Metastases or secondary deposits account for 16% of the malignant neoplasms involving the major salivary glands. A correct diagnosis of a secondary neoplasm is important to avoid unnecessary radical surgery and to guide further therapy. Fine-needle aspiration biopsy (FNAB) is an excellent noninvasive diagnostic tool for evaluating salivary gland lesions. We reviewed 36 secondary malignant salivary gland neoplasms evaluated by FNAB. Ancillary studies were performed in selected cases. Follow-up included clinical correlation and review of histologic material. For 4 adenocarcinomas, 4 squamous cell carcinomas, 1 undifferentiated carcinoma, 1 cutaneous basal cell carcinoma, 10 cutaneous melanomas including 1 desmoplastic variant, 3 osteosarcomas, 11 non-Hodgkin lymphomas, and 2 multiple myelomas, there was 1 false-negative FNAB result. The desmoplastic melanoma was interpreted as reactive lymphoid hyperplasia. A malignant diagnosis was given in all remaining cases except the secondary basal cell carcinoma, which was diagnosed as a neoplasm with basal cell features. FNAB is a reliable tool to differentiate hematologic malignant neoplasms and melanomas from other salivary gland neoplasms. A complete knowledge of the clinical history, review of previous pathologic materials, and, in some instances, the use of ancillary studies are crucial for recognizing solid malignant neoplasms secondarily involving the salivary glands.  相似文献   
30.
Summary The relationships of VII and VIII cranial nerves and related arteries are reviewed in 26 preparations by microdissection techniques. These vessels may be grouped in large (AICA, PICA), medium (LA, SA, CSA, RPI) and small calibre (vasa nervorum, radicullar and medullar branches). The importance of these structures in acoustic neuroma surgery, vestibular neurectomy and cross-compression syndromes is discussed. Vascular loops and elongated arteries are normal structures present at birth.This work was supported by a grant from the AJ Roemmers Foundation  相似文献   
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