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71.
72.
VD Badikov LE Zhuravleva VN Bolekhan IuG Tikhonov KV Maza?shvili 《Canadian Metallurgical Quarterly》1998,(7):17-19
The new method for microbiological analysis of blood in patients with pyoseptic infections is based on separate inoculations of plasma, erythrocyte mass, and leukocyte layer in nutrient medium providing conditions for growth of a wide spectrum of aerobes and obligate anaerobes. The method in general ensures a more rapid result and permits differentiation between true and false-positive bacteremia and between stages of septic process (bacteremia and septicemia). 相似文献
73.
D Gems AJ Sutton ML Sundermeyer PS Albert KV King ML Edgley PL Larsen DL Riddle 《Canadian Metallurgical Quarterly》1998,150(1):129-155
The nematode Caenorhabditis elegans responds to overcrowding and scarcity of food by arresting development as a dauer larva, a nonfeeding, long-lived, stress-resistant, alternative third-larval stage. Previous work has shown that mutations in the genes daf-2 (encoding a member of the insulin receptor family) and age-1 (encoding a PI 3-kinase) result in constitutive formation of dauer larvae (Daf-c), increased adult longevity (Age), and increased intrinsic thermotolerance (Itt). Some daf-2 mutants have additional developmental, behavioral, and reproductive defects. We have characterized in detail 15 temperature-sensitive and 1 nonconditional daf-2 allele to investigate the extent of daf-2 mutant defects and to examine whether specific mutant traits correlate with each other. The greatest longevity seen in daf-2 mutant adults was approximately three times that of wild type. The temperature-sensitive daf-2 mutants fell into two overlapping classes, including eight class 1 mutants, which are Daf-c, Age, and Itt, and exhibit low levels of L1 arrest at 25.5 degrees. Seven class 2 mutants also exhibit the class 1 defects as well as some or all of the following: reduced adult motility, abnormal adult body and gonad morphology, high levels of embryonic and L1 arrest, production of progeny late in life, and reduced brood size. The strengths of the Daf-c, Age, and Itt phenotypes largely correlated with each other but not with the strength of class 2-specific defects. This suggests that the DAF-2 receptor is bifunctional. Examination of the null phenotype revealed a maternally rescued egg, L1 lethal component, and a nonconditional Daf-c component. With respect to the Daf-c phenotype, the dauer-defective (Daf-d) mutation daf-12(m20) was epistatic to daf-2 class 1 alleles but not the severe class 2 alleles tested. All daf-2 mutant defects were suppressed by the daf-d mutation daf-16(m26). Our findings suggest a new model for daf-2, age-1, daf-12, and daf-16 interactions. 相似文献
74.
75.
The electrophysiological integrity of the adult rat spinal cord was assessed at the lumbar, lower cervical and cortical levels after the animals sustained a severe contusion injury at the mid-thoracic level (T8) and received either carbon filament cultured with fetal spinal cord tissue implants, fetal tissue implants, or carbon filament implants alone. Somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs) were recorded from all animal groups at the end of the 8-week survival period. The results of this study demonstrate that the spinal cord injured animals that received carbon filament cultured with fetal spinal cord tissue implants had the highest degree of electrophysiological recovery, indicating that this combination plays an important role in promoting recovery after injury. 相似文献
76.
GS Dveksler SE Gagneten CA Scanga CB Cardellichio KV Holmes 《Canadian Metallurgical Quarterly》1996,70(6):4142-4145
Mouse hepatitis virus (MHV) receptor, the receptor for the murine coronavirus MHV, was expressed in MHV-resistant hamster and human cells as a series of mutant, recombinant glycoproteins with carboxy-terminal deletions lacking the cytoplasmic tail, transmembrane domain, and various amounts of the immunoglobulin constant-region-like domains. The soluble receptor glycoproteins containing the N-terminal virus-binding domain were released into the supernatant medium and inactivated the infectivity of MHV-A59 virions in a concentration-dependent manner. Surprisingly, some of the anchorless glycoproteins were found on the plasma membranes of transfected cells by flow cytometry, and these cells were rendered susceptible to infection with three strains of MHV. Thus, in the cells in which the anchorless, recombinant receptor glycoprotein is synthesized, some of the protein is bound to an unidentified moiety on the plasma membrane, which allows it to serve as a functional virus receptor. 相似文献
77.
A study of reversibly inactivated lipases for use in a morphine-triggered naltrexone delivery system
GR Nakayama KV Roskos BK Fritzinger J Heller 《Canadian Metallurgical Quarterly》1995,29(11):1389-1396
A key component of an implant that can be triggered by external morphine to release naltrexone is an inactivated enzyme that can be activated by morphine and which can then rapidly remove a protective coating surrounding a bioerodible polymer containing dispersed naltrexone. In this article we describe a lipase that has been conjugated with O3-carboxymethylmorphine, morphine-beta-3-glucuronide and O3-carboxypropylmorphine. The enzyme conjugate was then inactivated by complexation with affinity-purified goat polyclonal antimorphine antibodies. Antibody lipase interactions were measured by pH Stat and ELISA techniques. Affinity constants of the antibodies determined by radioimmunoassay using tritium-labeled morphine were 4.10 x 10(6), 3.18 x 10(6) and 3.38 x 10(7), respectively. While a concentration of 10(-5)M morphine was required to restore lipase activity, it is likely that a combination of correct morphine tether and correct affinity-purified antibody can increase sensitivity to the desired 10(-8)10(-9)M morphine level. Thus, a functioning device can almost certainly be constructed. However, it is unlikely that reactivation times of 1-2 h necessary for clinical usefulness in treatment of narcotic addiction can be achieved. 相似文献
78.
79.
Hyperlipidemia was identified in an 11-yr-old male cheetah (Acinonyx jubatus) and three related 3-yr-old male cheetah littermates. Hyperlipidemia in these four cheetahs was characterized by hypertriglyceridemia and hypercholesterolemia. The mean percentages of chylomicron and beta-lipoproteins were greater (P < 0.05) and the mean percent of alpha-lipoproteins was lower (P < 0.05) than the respective means for a group of 20 nonhyperlipidemic and clinically normal cheetahs. The etiology of the hyperlipidemia in these four cheetahs was not determined. However, the older cheetah also had chronic renal insufficiency and a parathyroid adenoma, conditions that have been associated with hyperlipidemia. 相似文献
80.
L Lindenskov FB Kristensen AM Andersen KV Andersen N Hermann VW Knudsen HK Nielsen 《Canadian Metallurgical Quarterly》1994,156(19):2897-2901
The study was conducted in order to describe the extent and content of advice on common ailments in pregnancy given by doctor or midwife during prenatal visits and to describe the frequency of ailments in the period before the visits. The design was a nationwide cross-sectional study based on questionnaires completed by pregnant women who had seen a general practitioner (GP), midwife or hospital doctor for prenatal care. Ailments and advice in connection with one specific visit were reported. The questionnaires were completed by 517 women after a prenatal visit to their GP (92% of eligible), by 514 women after a prenatal visit to the midwife (91% of eligible), and by 203 women after a prenatal visit to a doctor in the maternity department in pregnancy week 16-18 (84% of eligible). The results showed that nausea, pollakisuria, tiredness and heartburn had been present during the period before the visit in about half the women. Between a third and a fourth of the women had been discomforted by back pain, discharge or cramps. From 15 to 58 percent had been given advice, depending on the symptom. The advice was of many different kinds. To a large extent the women wanted to talk to the health professionals about the ailments, and most often they wanted to talk to a midwife about the ailments. We conclude that common ailments of pregnancy are frequent and they should be investigated more. Nearly all pregnant women want to talk about the subject during prenatal visits. The objectives of giving advice should be clearer, and clinical studies of the effectiveness of the advice are needed. 相似文献