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991.
992.
CM Mueller T Colaizzo-Anas EP Shronts JA Gaines 《Canadian Metallurgical Quarterly》1996,96(8):764-8; quiz 769-70
OBJECTIVES: The purpose of the study was to describe the involvement of registered dietitians in parenteral nutrition (PN) orders, to identify characteristics of those who write orders; and to rank education, training, and support elements that dietitians believe facilitate PN order-writing skills. DESIGN: Mail survey method. SUBJECTS: Usable returned questionnaires (n = 266) represented randomly sampled membership of the Dietitians in Nutrition Support (a dietetic practice group of The American Dietetic Association) and registered dietitian membership of the American Society of Parenteral and Enteral Nutrition. STATISTICAL ANALYSIS: Data were analyzed using basic frequency displays on all questionnaire items, Pearson correlations between the quantitative variables, and one-way analysis of variance with each of the categorical variables and the quantitative variables. Detail exploration among variables was done by chi(2) analyses and two-tailed t tests. RESULTS: "Recommend" was the most frequent response to a query about participation in PN orders. An average of 37% of respondents sometimes or always wrote orders for nutrients. Specialists were more likely to write orders than clinicians and managers. No relationship was found between those who wrote orders and educational level, and writers had been registered for a shorter length of time. Agreement on the training and support needed for order-writing skills was nearly unanimous. APPLICATIONS: The PN skills of respondents who were specialists distinguished them from managers and clinicians. Specialists did not fit criteria for advanced practice, and specialty practice in metabolic nutrition care may be too broad to define their practice. Educators must recognize the importance of including PN training in didactic and clinical training programs. Registered dietitians with PN skills will be well positioned to play an active role in the evolving health care system. 相似文献
993.
C Hol C Schalén CM Verduin EE Van Dijke J Verhoef A Fleer H Van Dijk 《Canadian Metallurgical Quarterly》1996,174(3):636-638
The complement phenotypes of Moraxella catarrhalis isolates obtained from adult patients with acute laryngitis were investigated using a microliter serum bactericidal assay and compared with those of other donor groups. Laryngitis isolates had a higher proportion (57%) of complement-resistant strains than did carrier strains from healthy 8- to 13-year-old schoolchildren (16%). The difference between these groups was statistically significant (chi2 [3 x 2 table] = 21.55; P < .001). The relatively frequent occurrence of the complement-resistant (virulence-associated) phenotype in adults with acute laryngitis supports the theory of an active role of M. catarrhalis in the pathogenesis of acute laryngitis. 相似文献
994.
995.
Chin morphology and sexual dimorphism in the fossil hominid mandible sample from Klasies River Mouth
The site of Klasies River Mouth (KRM) in South Africa has produced a small sample of early Upper Pleistocene hominid remains that have been a focus for discussions of the origins of modern humans. Despite certain primitive characteristics exhibited by these fossils, proponents of a single recent origin have attributed them to early modern humans. Critics of this hypothesis have emphasized the significance of the archaic features evident in this sample, including the absence of pronounced chins among the mandibular specimens. This study compares the size range and chin morphology exhibited by the KRM mandibles with that of Neandertals, Upper Pleistocene humans, and recent humans. The extreme sexual dimorphism documented among the KRM fossils reflects the presence of a very small individual, and previous efforts to classify the KRM sample as archaic on the basis of their robusticity have failed to address the significance of this diminutive hominid. While each KRM fossil falls within the 95% envelope of variability established for chin development in a comparative modern sample, a similarly low frequency of pronounced chins is very unlikely to be found in any recent human population. The morphological pattern of the KRM mandibles is clearly distinct from that of Neandertals and of recent humans. 相似文献
996.
OBJECTIVE: To identify the origin of eosinophils in cases of eosinophil-associated preterm delivery. METHODS: From an established set of 465 consecutive non-anomalous singleton infants delivered at 22-32 weeks' gestation, we retrieved 161 cases of preterm delivery following spontaneous onset of preterm labor, 78 cases with maternal preeclampsia, 33 cases of abruption, and 193 cases of premature rupture of membranes (PROM). Charts were reviewed, and the placenta, umbilical cord, and membranes were examined histologically. In cases with extravascular eosinophils showing evident gradient toward the amniotic cavity, the origin of the eosinophils (fetal or maternal) was determined by the proximity to fetal or maternal vessels. RESULTS: Histologic evidence of an eosinophilic gradient toward the amniotic cavity was present only in the fetal (including umbilical cord and chorion) compartments. This eosinophilic gradient was present in 19% (90 of 465) of preterm delivery cases and was significantly more common in cases of PROM (54 of 193, 28%) and preterm labor (34 of 161, 21%) than abruption (two of 33, 6%) and preeclampsia (none of 78) (P < .001). In 84 of 90 cases (93%), the eosinophilic gradient was present along with multiple histologic indicators of acute intrauterine inflammation. CONCLUSION: An eosinophilic gradient toward the amniotic cavity, present in nearly a fifth of cases of preterm delivery, is probably of fetal origin, making it unlikely that a maternal "allergy-like" mechanism is a cause of preterm delivery. 相似文献
997.
CM Owczarek MJ Layton LG Robb NA Nicola CG Begley 《Canadian Metallurgical Quarterly》1996,271(10):5495-5504
998.
BACKGROUND AND OBJECTIVES: Little is known about resolution of serum and cerebrospinal fluid abnormalities after neurosyphilis treatment, especially in patients infected with human immunodeficiency virus (HIV). GOAL: To examine the time course of resolution of these abnormalities. STUDY DESIGN: Case series of 22 patients with neurosyphilis (13 infected with HIV) with reactive cerebrospinal fluid Venereal Disease Research Laboratory test who underwent at least one lumbar puncture after treatment. RESULTS: Resolution of all serum and cerebrospinal fluid measures was slower in patients infected with HIV. Serum and cerebrospinal fluid abnormalities resolved in most patients not infected with HIV by 30 weeks, and all met Centers for Disease Control and Prevention criteria for cure. One patient infected with HIV failed therapy by Centers for Disease Control and Prevention criteria, and three others had persistent pleocytosis. CONCLUSIONS: HIV-infected patients with neurosyphilis have slower resolution of serum and cerebrospinal fluid abnormalities after therapy. This observation may suggest impaired clearance of Treponema pallidum from the central nervous system. 相似文献
999.
AP Zis LN Yatham RW Lam CM Clark M Srisurapanont K McGarvey 《Canadian Metallurgical Quarterly》1996,15(3):263-270
The corneal wound-healing properties of fibronectin (FN) and a fibronectin hydrolysate (FNH) have been evaluated in comparison with commonly used drugs. Nonpenetrating bilateral surgical keratectomy was performed in male albino rabbits. The left eye was treated with the active product, whereas the right eye served as a control (vehicle). The healing area was measured by planimetry after fluorescein staining at 0, 24, 48, and 72 h after keratectomy. Histological and immunohistochemical analysis of the healing process was also performed. Results were as follows: (a) Nandrolone (p < 0.005) and asiaticoside (p < 0.001), both at 10 mg/ml, in eyedrops delayed the healing process. (b) An ointment containing vitamin A and amino acids also delayed the process but at the limit of statistical significance (p = 0.055). (c) FNH (20-80 mg prot/ml) significantly improved the quality and shortened the time of the healing process at 60 mg prot/ml and above. (d) Human FN (100-800 micrograms/ml) did not affect the healing process. Immunohistochemical analysis demonstrated that FNH accelerated the appearance of endogenous FN in the damaged cornea earlier than in the control eyes. It is concluded that FNH may be useful in the management of corneal wounds, whereas the effectiveness of FN is doubtful. 相似文献
1000.
Intercellular communication is mediated by specialized cell-cell contact areas known as gap junctions. Connexins are the constitutive proteins of gap junction intercellular channels. Various cell expression systems are used to express connexins and, in turn, these expression systems can then be tested for their ability to form functional cell-cell channels. In this review, expression of murine endogenous connexins in primary cells and established cell lines is compared with results obtained by expression of exogenous connexins in Xenopus oocytes and cultured mammalian cells. In addition, first reports on characterization of connexin-deficient mice are discussed. 相似文献