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991.
992.
SD Ross A DiGeorge JE Connelly GW Whiting N McDonnell 《Canadian Metallurgical Quarterly》1998,18(6):1290-1297
We performed a literature search for all clinical studies reporting outcomes in patients with the acquired immunodeficiency syndrome (AIDS) receiving granulocyte-macrophage colony-stimulating factor (GM-CSF) for any indication. Safety outcomes included human immunodeficiency virus replication, immune status, and frequency of opportunistic infections and neoplasms. Data were synthesized qualitatively. We identified 22 studies (274 patients): 12 addressed AIDS neutropenia, 8 AIDS cancer therapy, and 2 opportunistic infections. Viral burden was assessed by serum p24Ag in 15 studies. Nine reported no change in levels, three net decreases, and three net increases. All studies showing net increases involved patients receiving GM-CSF without a concurrent antiretroviral. The CD4 counts were unchanged in 5 studies, increased in 3, and not reported in 14. The incidence of neoplasms or new opportunistic infections was low. The literature suggests no increased risk of viral replication or clinical deterioration in patients with AIDS who take GM-CSF concurrently with zidovudine. 相似文献
993.
AF Clark MG Sharp SD Morley S Fleming J Peters JJ Mullins 《Canadian Metallurgical Quarterly》1997,272(29):18185-18190
The secretion of renin from granules stored in renal juxtaglomerular cells plays a key role in blood pressure homeostasis. The synthesis and release of renin and the extent of granulation is regulated by several mechanisms including signaling from the macula densa, neuronal input, and blood pressure. Through the use of a gene-targeting vector containing homology arms generated using the polymerase chain reaction, we have inactivated the Ren-1(d) gene, one of two mouse genes encoding renin, and report that lack of renin-1(d) results in altered morphology of the macula densa of the kidney distal tubule and complete absence of juxtaglomerular cell granulation. Furthermore, Ren-1(d-/-) mice exhibit sexually dimorphic hypotension. The altered growth morphology of the macula densa in Ren-1(d)-null mice should provide a tool for the investigation of the JG cell-macula densa signaling. Furthermore, the current data indicate that expression of the Ren-1(d) gene is a prerequisite for the formation of storage granules, even though the related protein renin-2 is present in these mice, suggesting that renin-1(d) and renin-2 are secreted by distinct pathways in vivo. 相似文献
994.
Most mitochondrial proteins are nuclear encoded, synthesized on cytosolic ribosomes, and imported into the mitochondria. We have identified and characterized a 309 amino acid human protein with a molecular weight of 34 kDa that functions as a subunit of the translocase for the import of such proteins. hTom34 (34-kDa Translocase of the Outer Mitochondrial Membrane) is displayed on the surface of mitochondria and is resistant to extraction under alkaline conditions. Antibodies raised against hTom34 specifically inhibit in vitro import of the mitochondrial precursor protein preornithine transcarbamylase into mitochondria isolated from rat liver. Based on trypsin digestion experiments, the receptor has a large (27 kDa) C-terminal domain exposed to the cytosol. This novel component of the protein import machinery possesses a 62 residue motif conserved with the Tom70 family of mitochondrial receptors but otherwise appears to have no counterpart so far characterized in the mitochondria of any other species. 相似文献
995.
Yao P; Xie Y; Wang YH; Sun YL; Huang ZX; Xiao GT; Wang SD 《Protein engineering, design & selection : PEDS》1997,10(5):575-581
Phenylalanine-35, which is a residue of the hydrophobic patch on the
surface of cytochrome b5, has been mutated into Tyr35, His35 and Leu35 to
elucidate the functions of the Phe35 and give further insight into the
roles of the hydrophobic patch and/or aromatic network. The effects of
these mutations on the heme environment, denaturation towards heating and
the denaturant urea, redox potential and stability of protein were studied.
The relative stability of cytochrome b5 and its mutants towards heating has
the order Phe35Tyr > wild type > Phe35Leu > Phe35His in the
oxidized state and wild type > Phe35Tyr > Phe35Leu > Phe35His in
the reduced state. All the mutants exhibit decreased reduction potentials:
Phe35Tyr -66 mV, Phe35His -51 mV and Phe35Leu -28 mV, which are more
negative than that of the wild type. The order of redox potential reflects
the relative stability in the oxidized and reduced states. A method of
producing multiple mutants at a single site of a gene is also described for
the first time.
相似文献
996.
997.
SD Eckford M James SR Jackson AJ Hamer JJ Browning 《Canadian Metallurgical Quarterly》1997,104(10):1209-1211
Measures that can be taken to reduce exposure to potentially infected body fluids are of particular relevance in obstetric and gynaecological surgery due to high rates of glove puncture and relatively higher prevalence of human immunodeficiency virus seropositivity in the obstetric age group. We describe the use of a simple electronic device that alarms following puncture of surgical gloves or the creation of a fluid bridge between surgeon and patient. Further exposure to potentially infected body fluids is thus prevented. This present study was performed in the context of caesarean section, but the application of the technique to gynaecological procedures is appropriate. 相似文献
998.
CI Henschke DF Yankelevitz A Wand SD Davis M Shiau 《Canadian Metallurgical Quarterly》1997,21(2):90-103
Proper positioning and assessment of abnormalities and complications of the above-mentioned devices have a significant impact on the management of critically ill patients in the intensive care unit (ICU). The timely assessment of new or rapidly evolving findings is critical. Optimal radiographic technique, availability of images to the clinicians, and rapid reporting by the radiologist all serve to maximize the efficacy of bedside chest radiography in the ICU. Sometimes, changes in cardiopulmonary status may only be appreciated on chest radiographs (CXRs). Complications from ventilatory assistance, such as barotrauma, occur frequently and must be detected promptly. The position of monitoring devices, an important component of critical care management, is best checked radiographically. Indications for CXRs and the recommended frequency for repeat follow-up CXRs are based on the existing literature and the consensus of an expert panel formed by the American College of Radiology. 相似文献
999.
1000.
Dual-coding theory argues that processing advantages for concrete over abstract (verbal) stimuli result from the operation of 2 systems (i.e., imaginal and verbal) for concrete stimuli, rather than just 1 (for abstract stimuli). These verbal and imaginal systems have been linked with the left and right hemispheres of the brain, respectively. Context-availability theory argues that concreteness effects result from processing differences in a single system. The merits of these theories were investigated by examining the topographic distribution of event-related potentials (ERPs) in 2 experiments (lexical decision and concrete-abstract classification). The results were most consistent with dual-coding theory. In particular, different scalp distributions of an N400-like negativity were elicited by concrete and abstract words. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献