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991.
Fever in neutropenic cancer patients is often due to the development of an infection. The standard management of febrile neutropenic patients involves the administration of empiric, hospital-based, parenteral antibiotic therapy. Although this treatment strategy has evolved from experience in high-risk patients with hematological malignancies, in whom bacterial infection can result in substantial morbidity and mortality, it has been adopted for all patients with febrile neutropenia, largely because of the inability of clinicians to reliably distinguish between patients who are at high risk for developing such morbidity/mortality and those who are not. The development of risk-assessment models has facilitated the recognition of high-, moderate-, and low-risk subgroups among febrile neutropenic patients and allows the administration of outpatient antibiotic therapy to the moderate- and low-risk groups, with the same degree of efficacy and safety as hospital-based therapy. Monotherapy with the carbapenems (imipenem/cilastatin and meropenem), with their broad spectrum of activity and established efficacy in high-risk patients, represents realistic options for risk-based treatment of febrile neutropenic patients within and outside the hospital setting. 相似文献
992.
Does cognition in the disconnected right hemisphere require right hemisphere possession of language?
JE Bogen 《Canadian Metallurgical Quarterly》1997,57(1):12-21
It has been asserted at times that the human right hemisphere is cognitively inferior to that of a chimpanzee or even a monkey. Related is the even stronger claim that human consciousness, as well as cognition, requires language. These claims are discussed, and counterexamples are presented from both split-brain subjects and patients hemispherectomized in adulthood after customary development as righthanders. 相似文献
993.
Maternal tolerance of the fetal allograft remains poorly understood. In humans, expression of the highly polymorphic classical HLA-A and HLA-B loci is suppressed, while expression of the nonclassical HLA-G locus is up-regulated at the maternal-fetal interface. Like other nonclassical MHC class I molecules, HLA-G exhibits limited diversity, but certain characteristics of HLA-G distinguish it from other nonclassical MHC class I molecules: it has a truncated cytoplasmic domain, it is the product of alternatively spliced mRNAs, and it is expressed primarily in the placenta. We have examined MHC class I expression in the placenta of the rhesus monkey to determine whether this animal is a suitable model in which to study the function of HLA-G. Although the rhesus monkey possesses orthologs of many MHC class I and II loci found in humans, the HLA-G ortholog is a pseudogene in this nonhuman primate species. In this study, we report the identification of a novel nonclassical MHC class I locus expressed in the placenta of the rhesus monkey, Mamu-AG (Macaca mulatta-AG). Although unrelated to HLA-G, Mamu-AG encodes glycoproteins with all of the characteristics of HLA-G. These Mamu-AG glycoproteins are limited in their diversity, possess truncated cytoplasmic domains, are the products of alternatively spliced mRNAs, and their expression is restricted to the placenta. Taken together, these data suggest that convergent evolution may have resulted in the expression of a unique nonclassical MHC class I molecule in the rhesus monkey placenta, and that the common structural features of Mamu-AG and HLA-G may be functionally significant. 相似文献
994.
YL Tsai J Liu JE Garcia E Katz G Compton TA Baramki 《Canadian Metallurgical Quarterly》1997,12(5):1111-1113
In order to find an optimal hypo-osmotic swelling test (HOST) and to identify viable sperm cells from patients with asthenozoospermia for intracytoplasmic sperm injection (ICSI), we tested single motile and non-motile spermatozoa in four hypo-osmotic solutions by micromanipulation. The four solutions were: A, H2O; B, 50 mOsm NaCl; C, 150 mOsm NaCl and D, 150 mOsm sodium citrate and fructose. Eosin Y staining was then carried out for evaluation of viability of the spermatozoa after HOST. Using motile spermatozoa, no statistical difference was found in HOST-positive spermatozoa between these four solutions. There were more viable sperm cells after HOST in solutions C and D, as noted by Eosin Y staining. After non-motile spermatozoa were incubated for 1 min in the four solutions, HOST with solution C gave the best results for identification of viable sperm cells compared to the other three solutions. When motile spermatozoa were incubated in solution C or solution D for 30 min, the result of HOST with solution C (10.8% dead spermatozoa) was superior to that of solution D (49.1% dead spermatozoa). In conclusion, the HOST protocol using 150 mOsm NaCl (solution C) for 1 min yielded the best results for selection of viable spermatozoa. This procedure should be used for selection of viable spermatozoa for ICSI in patients with 100% non-motile spermatozoa. 相似文献
995.
JE Baggott CB Robinson I Eto GL Johanning PE Cornwell 《Canadian Metallurgical Quarterly》1998,71(3-4):181-187
It is shown how to calculate random errors in chemical shift tensor components and in the Euler angles which fix the orientation of the sigma tensor in the molecular frame, as obtained from spinning sideband analysis of MAS NMR spectra of powdered solids, when heteronuclear dipolar coupling interactions occur in a two spin system. The procedure was applied to experimental data corresponding to the chemical shift tensor of a carbon-13 bonded to a phosphorus-31 nucleus. Clues are given concerning the experimental variables to be set in order to obtain the desired accuracy in the orientation angles. 相似文献
996.
997.
Extensive proton hyperfine-shifted resonance assignments have been made for wild-type yeast iso-1-ferricytochrome c when it is free in solution and when it is noncovalently complexed to resting state cytochrome c peroxidase. Complete heme proton resonance assignments were made for free iso-1-ferricytochrome c, while for CcP-complexed iso-1-ferricytochrome c, 70% of heme proton assignments were made. Additional proton resonance assignments were made for hyperfine-shifted protons of amino acids near the heme. These assignments allowed identification of the most extensive set of complex-induced proton shifts yet reported for CcP/cytochrome c complexes. Several purely dipolar-shifted resonances from heme vicinity amino acid protons were also assigned in both free and complexed iso-1-ferricyt c. Both sets of resonance assignments allowed assessment of the origin of proton complex-induced shifts. Using the assigned dipolar-shifted proton resonances as a basis, the orientations of the principal axis systems of the paramagnetic susceptibility tensors for free and cytochrome c peroxidase-bound iso-1-ferricytochrome c were elucidated. The results indicated that the iso-1-ferricytochrome c magnetic axis system orientation shifts significantly upon complex formation. The direction of the complex-induced shifts for heme proton resonances is largely accounted for by the magnetic anisotropy changes. However, analysis of heme complex-induced shifts also reveals local changes in magnetic environment for two heme substituents, presumably through a specific structure change. 相似文献
998.
PH Wiernik DF Moore JM Bennett SE Vogl JE Harris S Luger MM Oken JH Glick 《Canadian Metallurgical Quarterly》1998,30(5-6):601-607
Mitoguazone, an investigational agent with significant activity in advanced lymphoma, was added to a modified CHOP regimen (COPA) in an effort to improve the activity of standard therapy in 66 previously untreated patients with stages II-IV lymphoma and diffuse histology of intermediate or high grade other than lymphoblastic in this phase II pilot study. The regimen was well tolerated and the complete response rate in diffuse large cell lymphoma was 55%. Sixty-five percent of all complete responders were in complete response for at least one year. Despite these excellent results. it is unlikely that the addition of mitoguazone improved results compared with those obtained with standard therapy alone, since similar results have been frequently reported with the latter. 相似文献
999.
Novel thyrotropin-releasing hormone (TRH, pGlu-His-Pro-NH2) analogs, made by solid phase, were derived from the general scaffold pGlu-(D/L)Agl(X)-Pro-NH2 where Agl = aminoglycine. Analogs ranged from X being a proton to an acylating agent derived from substituted (aromatic heterocyclic rings) formic or acetic acids or an aminotriazolyl moiety (3'-amino-1H-1',2',4'-triazolyl) built on N(alpha) of aminoglycine or Nbeta of alpha,beta-diaminoproprionic acid (Dpr). X was expected to mimic the electronic and structural characteristics of the imidazole ring of histidine. Analogs were purified by HPLC, characterized by mass spectrometry and isolated as either diastereoisomeric mixtures or pure isomers. Analogs, tested for their binding affinity to mouse pituitary TRH receptors, have apparent equilibrium inhibitory constants > 1 microM. 相似文献
1000.
JE Foley JM Lapointe P Koblik A Poland NC Pedersen 《Canadian Metallurgical Quarterly》1998,12(6):415-423
Feline infectious peritonitis (FIP) is a fatal Arthus-type immune response of cats to infection with FIP virus, a mutant of the ubiquitous feline enteric coronavirus (FECV). The disease may occur systemically or in any single organ system, and primary neurologic disease is a common subset of such manifestations. We examined 16 domestic cats with clinical neurologic FIP and 8 control cats with nonneurologic FIP, with the intention of identifying the ante- and postmortem diagnostic tests that most contribute to accurate diagnosis. Of the 16 cats with neurologic FIP, 15 were less than 2 years of age and all 16 originated from large multiple-cat households. The most useful antemortem indicators of disease were positive anti-coronavirus IgG titer in cerebrospinal fluid, high serum total protein concentration, and findings on magnetic resonance imaging suggesting periventricular contrast enhancement, ventricular dilatation, and hydrocephalus. Postmortem diagnosis was facilitated by FIP monoclonal antibody staining of affected tissue and coronavirus-specific polymerase chain reaction. Most cats with neurologic and ocular forms of FIP had patchy, focal lesions, suggesting that recently developed technologies described in this report may be useful for evaluation of cats with suspected FIP. 相似文献