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As previously reported, pancreatic acinar cell necrosis and inflammation develop in mice a few hours after one intraperitoneal injection of foreign serum. However, sublethally injured acinar cells exhibited notable increases in both zymogen granule numbers and amylase activity, observed within 3 hours and increasing with time. These two changes were coupled with a progressive decrease in the secretory response to pilocarpine and were preceded by significant disturbances in pancreatic tissue concentrations of sodium and potassium. We conclude that (1) the granule increase results from an induced disturbance of the granule exocytosis mechanism while granule formation continues and, therefore, (2) the granule secretory process is more sensitive to the serum injury mechanism than is the zymogen synthesis process. Although the granule increases developed in acinar cells throughout most of the nonnecrotic gland and persisted for at least 24 hours, acinar cell necrosis was maximal in extent--approximately 25% of the gland in severest form--by 12 to 15 hours. We conclude, therefore, that the increase in granules is neither the primary determinant nor initiator of acinar cell death. The latter is likely caused by disturbed plasma membrane functions, sufficient in some cells to result in lethal changes in ion and fluid composition. The injury mechanism, which permits granule formation to go on in the face of impaired granule exocytosis, is yet to be worked out. The possibilities are discussed in relationship to the reactivity of foreign sera for target cell plasma membranes. 相似文献
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FE Dougherty 《Canadian Metallurgical Quarterly》1976,44(6):889-897
Exp I (a) established outcome criteria using evaluation ratings from 24 patient-therapist dyads; (b) produced 11 quantifiable personality predictors through factor analysis of 18 therapists' and 65 patients' scores on a test battery (including the MMPI and the Omnibus Personality Inventory); (c) identified 3 typological categories of both patients and therapists homogeneous with respect to these variables and 2 groups of therapists each homogeneous with respect to therapeutic approach; and (d) derived 5 regression equations predicting outcome for each patient and therapist group. Exp II, with 24 therapists and 56 patients who were university students or their spouses, utilized these findings to form 2 experimental dyad groups for which (a) optimal or (b) minimal therapist outcome ratings were predicted, and 2 control groups each for both optimal and deterioration matches that controlled for patient type and therapist type, respectively. Results indicate significant differences between mean outcome in the comparison of the deterioration-matched group both with its control and the optimally matched group. Findings demonstrate the usefulness of carefully planned matching techniques. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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FE Hardenbergh 《Canadian Metallurgical Quarterly》1977,8(3):70-81
Mere aphakia is not an indication for secondary intraocular lens implantation. However, many patients with positive indications may be benefited most strikingly by this procedure. These indications are illustrated and results of the author's first 65 secondary implantations are analyzed. 相似文献
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Absorption and distribution of polyunsaturated fatty acids was investigated in rats receiving lysophospholipids per os (30 mg kg-1). Lysophosphatidylcholine (lysoPC) increased [3H]arachidonate absorption and its incorporation into mucosal phosphatidylcholine. Transport of [3H]arachidonate by the phospholipid fraction of lymph lipoproteins and the level of [3H]arachidonate in plasma and liver lipids was also increased by lyso PC. Lysophosphatidylserine also increased [3H]arachidonate absorption but channeled the fatty acids into the aminophospholipid fraction of mucosal phospholipids, thus decreasing its efflux in lymph lipoproteins. As a consequence, lysophosphatidylserine caused [3H]arachidonate accumulation in mucosa. As similar results were obtained with [14C]linoleate, the data suggest that the addition of an appropriate lysophospholipid to the diet may direct absorption and distribution of polyunsaturated fatty acids. 相似文献
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In separate clinical trials, two preparations of recombinant interferon (IFN)-beta, IFN beta-1a and IFN beta-1b, reduced exacerbation rates in relapsing-remitting multiple sclerosis (RR-MS). Further, IFN beta-1a slows the progression of disability in patients with RR-MS. Although they are effective in the treatment of MS, use of these drugs is associated with both class-specific and agent-specific side effects. Class-specific side effects include fever, chills, myalgias, arthralgias, and other flulike symptoms beginning 2 to 6 hours after injection and resolving within 24 hours of injection. Transient worsening of preexisting MS symptoms also occurs infrequently. Agent-specific side effects include injection-site reactions with IFN beta-1b. Simple management strategies can be used to minimize these reactions, including patient education; tailoring the dose and time of administration of IFN-beta; and prescribing appropriate combinations of acetaminophen, non-steroidal anti-inflammatory drugs, and steroids. Although side effects tend to diminish with treatment, successful management allows long-term administration of these drugs to achieve a reduction in disease activity and commensurate improvement in outcomes. 相似文献