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991.
We present the rare case of a girl surviving intrauterine listeria brain stem meningoencephalitis, who subsequently developed hydrocephalus, a trapped IV ventricle and an intramedullary cyst. Such cases have been reported only infrequently, and in earlier cases modern imaging studies were not available. Magnetic resonance imaging has been helpful in our patient to delineate the lesions and plan further treatment. 相似文献
992.
993.
GT Ko JC Chan VT Yeung CC Chow LW Tsang JK Li WY So HP Wai CS Cockram 《Canadian Metallurgical Quarterly》1998,21(8):1221-1225
OBJECTIVE: To assess the validity of using fasting plasma glucose (FPG) concentrations in conjunction with HbA1c or fructosamine for the screening of diabetes in high-risk individuals. RESEARCH DESIGN AND METHODS: In this study 2,877 Hong Kong Chinese (565 [19.6%] men; 2,312 [80.4%] women) with various risk factors for glucose intolerance underwent a 75-g oral glucose tolerance test (OGTT) for screening of diabetes. The risk factors included a family history positive for diabetes, a history of gestational diabetes or impaired glucose tolerance, and obesity. RESULTS: Using World Health Organization (WHO) criteria, 1,593 (55.4%) had normal glucose tolerance, 657 (22.8%) had impaired glucose tolerance, and 627 (21.8%) had diabetes. When the 1997 American Diabetes Association (ADA) criteria were applied, 394 (13.7%) had diabetes with an FPG > or = 7.0 mmol/l. Using multiple receiver operating characteristic curve analysis, the paired values of an FPG of 5.6 mmol/l and a HbA1c of 5.5% gave an optimal sensitivity of 83.8% and specificity of 83.6% to predict a 2-h plasma glucose (PG) > or = 11.1 mmol/l. Likewise, the paired values of an FPG of 5.4 mmol/l and a fructosamine level of 235 mumol/l (n = 2,408) gave an optimal sensitivity of 81.5% and specificity of 83.2%. An FPG > or = 5.6 mmol/l and an HbA1c > or = 5.5% was 5.4-fold more likely to occur in diabetic subjects (based on the WHO criteria) compared with nondiabetic subjects. For paired parameters less than these values, the likelihood ratio of this occurring in diabetic subjects was only 0.11. Similarly, an FPG > or = 5.4 mmol/l and a fructosamine > or = 235 mumol/l was fivefold more likely to occur in diabetic subjects than in nondiabetic subjects, with both parameters less than these values having a likelihood ratio of 0.04. Using these paired values as initial screening tests, only subjects who had an FPG > or = 5.6 mmol/l and < 7.8 mmol/l and an HbA1c > or = 5.5% (n = 642) required an OGTT to confirm diabetes, thereby saving 77.7% [(2,877-642)/2,877] of the OGTTs performed. Similarly, only subjects who had an FPG > or = 5.4 mmol/l and < 7.8 mmol/l and a fructosamine > or = 235 mumol/l (n = 526) required OGTT to confirm diabetes, meaning that 78.2% [(2,408-526)/2,408] of the OGTTs could have been saved. Based on the 1997 ADA criterion of an FPG cutoff value of 7.0 mmol/l, the corresponding numbers of OGTTs to be saved were 82.6% and 85.5%, respectively. CONCLUSIONS: The paired values of FPG and HbA1c or FPG and fructosamine helped to identify potentially diabetic subjects, the diagnosis of which could be further confirmed by the 75-g OGTT. Using this approach approximately 80% of OGTTs could have been saved, depending on the diagnostic cutoff value of FPG. 相似文献
994.
FE McCutchan JK Carr M Bajani E Sanders-Buell TO Harry TC Stoeckli KE Robbins W Gashau A Nasidi W Janssens ML Kalish 《Canadian Metallurgical Quarterly》1999,254(2):226-234
Multiple human immunodeficiency virus type 1 (HIV-1) genetic subtypes, intersubtype recombinants, and group O have been found in west central Africa. In Nigeria, where HIV-1 prevalence is rising rapidly, characterization of HIV-1 strains has been limited. Each of three full-length genome sequences acquired to date shows evidence of recombination: two are largely subtype G with subtype A segments in the midgenome accessory region; the third, IbNG, is subtype G with the long terminal repeats and two segments of pol from subtype A. In this study, peripheral blood mononuclear cells obtained in 1994-1995 from 10 patients hospitalized in northeastern Nigeria were evaluated by sequencing of the complete envelope and, from 7 patients, a portion of gag. Four patients harbored subtype G viruses and six patients had recombinant viruses. Two had strains sharing the A/G recombinant structure of IbNG. Two had a previously undescribed recombinant, mostly subtype A, whose carboxyl-terminal gp41 could not be classified. An A/G recombinant different from IbNG but similar to CA1, a Cameroonian strain, was found in one patient. The remaining patient had a strain that was otherwise subtype G but shared an unclassified carboxyl-terminal gp41 segment with the CA1-like strains. Other subtypes and group O were not found. 相似文献
995.
Two abscesses were shown on CT in a 72-year-old man: one in the left hip and one in the left pelvic region that resulted from a motor vehicle collision that occurred 8 months earlier. Bone scintigraphy showed increased uptake in the left hip area. On Tc-99m HMPAO leukocyte imaging, the hip area appeared to be photopenic, and the abscess of the left pelvis was not identified. Incidental uptake in the left lung base appeared to be an active acute inflammatory process as evidenced by an infiltrating lesion in the left lower lung on a chest radiograph. Because leukocyte scintigraphy cannot detect the presence of a chronic inflammatory process in the absence of acute inflammatory cells, the patient's abscesses in the left hip and the left pelvis did not localize Tc-99m HMPAO-labeled neutrophils. The cold lesion in the left hip area was most likely caused by the lesion in the reticuloendothelial system (bone marrow); the unidentifiable pelvic lesion was related to the area(s) outside the reticuloendothelial system. In interpreting a labeled leukocyte image, clinicians should be alert to the stage (chronic or acute) and location (regardless of whether in the reticuloendothelial system) of infectious lesion(s). In this patient, a wide spectrum of manifestations was evident on leukocyte scintigraphy. 相似文献
996.
997.
Mammalian ribonucleases constitute one of the fastest evolving protein families in nature. The addition of a four-residue carboxyl-terminal tail: Glu-Asp-Ser-Thr (EDST) in human pancreatic ribonuclease (HPR) in comparison with bovine pancreatic RNase (RNase A) could have adaptive significance in humans. We have cloned and expressed human pancreatic ribonuclease in Escherichia coli to probe the influence of the four-residue extension and neighboring C-terminal residues on the biochemical properties of the enzyme. Removal of the C-terminal extension from HPR yielded an enzyme, HPR-(1-124)-peptide, with enhanced ability to cleave poly(C). HPR-(1-124)-peptide also exhibited a steep increase in thermal stability mimicking that known for RNase A. Wild-type HPR had significantly low thermal stability compared to RNase A. The study identifies the C-terminal boundary in the human pancreatic ribonuclease required for efficient catalysis. 相似文献
998.
The study focuses on adult children (n = 81) having the main responsibility for parents with dementia (study group). They were compared with children (n = 102) of non-demented parents (reference group). The children were interviewed about burden experienced. The interviews also secured information about the children's co-operation with the informal and formal network and their willingness to remain as caregivers during the progression of the disease or ageing process. The results showed that the daughters reported feeling more affection in their caregiving role than the sons. About one third of the participants in the study could not get relief from someone else. Eighty-nine per cent of the children in the study group and 76% of the children in the reference group were not willing to care for their parents in the family home during the progression of the disease, even if they were employed as caregivers. 相似文献
999.
JP Elliott JK Drackley CG Aldrich NR Merchen 《Canadian Metallurgical Quarterly》1997,75(10):2803-2812
Extracellular oxygen radicals produced by H9c2 rat heart cells in monolayer cultures during ischemia and subsequent reoxygenation were monitored using the luminol-horseradish peroxidase-enhanced chemiluminescence technique. As expected, the photon count diminishes during ischemia but again rapidly attains normal values following reoxygenation. In the presence of superoxide dismutase, this photon emission is repressed, as is also the case in the presence of diphenylene iodonium, a specific inhibitor of NADPH-oxidase activity. Thus, the conclusion seems justified that H9c2 rat heart cells in monolayer cultures produce superoxide radicals extracellularly due to an NADPH oxidase-like action. In order to characterize this extracellular superoxide-generating system, we determined its sensitivity to increased temperatures, inhibition of protein synthesis and perturbations of cytoskeletal structures. Heat shocks result in a delayed inactivation of the NADPH oxidase activity followed by recovery, the kinetics of which depend on the imposed heat shock temperature. This inactivation is independent of protein synthesis and actin cytoskeletal structures, but the recovery of the enzyme's activity is dependent on these entities. 相似文献
1000.
The gonadotropin-releasing hormone (GnRH) agonists are a relatively new class of drugs that are potentially effective in treating disorders that are aggravated either by estrogen or testosterone. GnRH agonists are effective in the treatment of endometriosis, as well as other disorders, such as advanced prostrate cancer, precocious puberty and uterine leiomyomata. While the GnRH agonists reduce the extent of the endometrial lesions and the occurrence of pelvic pain associated with endometriosis, these agents are associated with physical and psychiatric side effects. The adverse effects of these agents are consistent with the physiological effects of ovarian suppression, such as vasomotor instability, vaginal dryness, and headaches. Preliminary results of a prospective, double-blind placebo-controlled study and an open label trial indicates that depressive mood symptoms increase in women treated with GnRH agonist therapy for endometriosis. Additional evidence suggest that sertraline effectively manages depressive mood symptoms associated with GnRH agonist therapy. The reason for the decline in mood on GnRH agonists is postulated to be associated with the decline in estrogen levels. Effective treatment strategies for depressive mood symptoms in women on GnRH agonists therapy may offer insight into the mechanisms of action of estrogen on mood. 相似文献