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71.
Forearm bone mineral density (BMD) was investigated in women to identify osteoporosis at the spine or femoral neck (or both) defined by WHO criteria (T score -2.5) without requirement for fracture. BMD was measured by single-energy X-ray absorptiometry (DTX100) and by dual- energy X-ray absorptiometry (DXA) in the lumbar spine and femoral neck in 422 subjects aged 22-90 yr. A total of 62% of subjects with osteoporosis (at the spine, femoral neck, or both sites) were detected with 89% specificity [receiver operating characteristics (ROC) analysis] and included all subjects below forearm BMD 0.34 g/cm2. Conversely, above 0.419 g/cm2, only 10% of patients had osteoporosis. A total of 71.8% of women could be assigned either to those who warranted therapy (<0.34 g/cm2) or to those who did not (>0.419 g/cm2) with 90% certainty. Subjects with forearm BMD between 0.34 and 0.419 g/cm2, who constituted 28.2% of the total group and included 31% of subjects with osteoporosis, had a 40% chance of having osteoporosis. This leads to a high identification rate on subsequent DXA scanning, which is thus used efficiently.   相似文献   
72.
Patients with idiopathic, cyclic, and congenital neutropenia have recurrent severe bacterial infections. One hundred twenty-three patients with recurrent infections and severe chronic neutropenia (absolute neutrophil count < 0.5 x 10(9)/L) due to these diseases were enrolled in this multicenter phase III trial. They were randomized to either immediately beginning recombinant human granulocyte colony- stimulating factor (filgrastim) (3.45 to 11.50 micrograms/kg/d, subcutaneously) or entering a 4-month observation period followed by filgrastim administration. Blood neutrophil counts, bone marrow (BM) cell histology, and incidence and duration of infection-related events were monitored. Of the 123 patients enrolled, 120 received filgrastim. On therapy, 108 patients had a median absolute neutrophil count of > or = 1.5 x 10(9)/L. Examination of BM aspirates showed increased proportions of maturing neutrophils. Infection-related events were significantly decreased (P < .05) with approximately 50% reduction in the incidence and duration of infection-related events and almost 70% reduction in duration of antibiotic use. Asymptomatic splenic enlargement occurred frequently; adverse events frequently reported were bone pain, headache, and rash, which were generally mild and easily manageable. These data indicate that treatment of patients with severe chronic neutropenia with filgrastim results in a stimulation of BM production and maturation of neutrophils, an increase in circulating neutrophils, and a reduction in infection-related events.  相似文献   
73.
Hammouda  MW; Moroz  LA 《Blood》1987,70(2):564-567
Exercise and venous occlusion stimulate fibrinolysis. In addition to increased concentrations of tissue-type plasminogen activator (tPA) and increased plasmin-mediated fibrinolysis in plasma, these stimuli produce additional cellular-phase activity in blood that is of the same magnitude as the plasma response. To determine whether tPA alone, rather than other consequences of these stimuli, is responsible for the cellular response, the in vitro effects of tPA on whole blood, plasma, and calculated cellular-phase (whole blood minus plasma) activities were determined by solid-phase radiofibrin assay on venous blood from ten normal subjects (seven men, three women). At tPA concentrations encompassing physiological and therapeutic levels (5 to 100 ng/mL; 0.7 to 14 IU/mL), increments in whole blood were consistently in excess of those in companion plasma and represented increased cellular-phase activity equivalent in magnitude to the well-known increase in plasma activity. Fibrinolytic activity produced by 10 to 20 ng tPA/mL (1.4 to 2.8 IU/mL) was consistently detected in whole blood and plasma by 60 minutes, with higher concentrations (100 ng or 14 IU tPA/mL) detectable after a five-minute assay in all subjects. Thus, tPA alone, without invoking fibrinolytic factors extraneous to blood or other effects of exercise or venous occlusion, accounts for both cellular and plasma responses to these stimuli. The considerable cellular response, the mechanism of which remains to be elucidated, may constitute a determinant of individual therapeutic responsiveness to tPA.  相似文献   
74.
This investigation explores the discourse devices associated with high-quality personal narratives. The study examined normative characteristics of 11 high-quality personal narratives of a frightening experience identified (from a larger set of 72 narratives) for their effectiveness in engaging the audience. Lay ratings and an ethnographic interview with seven of the excellent storytellers further characterized the stories and validated their selection. Narratives of both African Americans and Caucasians were represented, and were similar in nature. The excellent narratives were longer, conveyed more fearful topics, and were more dramatic than average narratives. Drama was achieved through direct speech, prosodic shifts, voice changes, inclusion of multiple characters, repetition, and syntactic and semantic parallelism. Illustrative narrative excerpts are provided. This study illustrates the potential in pairing holistic and analytical approaches to narrative analysis.  相似文献   
75.

Background  

The prevalence of overweight and obesity in children has at least doubled in the past 25 years with a major impact on health. In 2005 a prevention protocol was developed applicable within Youth Health Care. This study aims to assess the effects of this protocol on prevalence of overweight and health behaviour among children.  相似文献   
76.

Background and purpose:

The studies described here are the first to evaluate the in vitro and in vivo properties of 111In-CHX-A″-panitumumab for radioimmunotherapy (α- and β--emitters) and radioimmunoimaging (single photon emission computed tomography and positron emission tomography).

Experimental approach:

Twenty-seven human carcinoma cell lines were analysed for expression of epidermal growth factor receptors by flow cytometry. Panitumumab was conjugated with CHX-A″-DTPA (diethylenetriamine-pentaacetic acid) and radiolabelled with 111In. Immunoreactivity of the CHX-A″-DTPA-panitumumab and 111In-CHX-A″-DTPA-panitumumab was evaluated by radioimmunoassays. Tumour targeting was determined in vivo by direct quantitation of tumour and normal tissues and by γ-scintigraphy.

Key results:

For 26 of 27 human tumour cell lines, 95% of the cells expressed epidermal growth factor receptors over a range of intensity. Immunoreactivity of panitumumab was retained after modification with CHX-A″-DTPA. Radiolabelling of the immunoconjugate with 111In was efficient with a specific activity of 19.5 ± 8.9 mCi·mg−1 obtained. Immunoreactivity and specificity of binding of the 111In-panitumumab was shown with A431 cells. Tumour targeting by 111In-panitumumab was demonstrated in athymic mice bearing A431, HT-29, LS-174T, SHAW or SKOV-3 s.c. xenografts with little uptake observed in normal tissues. The 111In-panitumumab was also evaluated in non-tumour-bearing mice. Pharmacokinetic studies compared the plasma retention time of the 111In-panitumumab in both non-tumour-bearing and A431 tumour-bearing mice. Tumour targeting was also visualized by γ-scintigraphy.

Conclusions and implications:

Panitumumab can be efficiently radiolabelled with 111In with high labelling yields. Based on the efficiency in tumour targeting and low normal tissue uptake, panitumumab may be an effective targeting component for radioimmunodiagnostic and radioimmunotherapeutic applications.  相似文献   
77.
Wessels MW, Willems PJ. Genetic factors in non‐syndromic congenital heart malformations. The genetic defect in most patients with non‐syndromic congenital heart malformations (CHM) is unknown, although more than 40 different genes have already been implicated. Only a minority of CHM seems to be due to monogenetic mutations, and the majority occurs sporadically. The multifactorial inheritance hypothesis of common diseases suggesting that the cumulative effect of multiple genetic and environmental risk factors leads to disease, might also apply for CHM. We review here the monogenic disease genes with high‐penetrance mutations, susceptibility genes with reduced‐penetrance mutations, and somatic mutations implicated in non‐syndromic CHM.  相似文献   
78.
Chronic toxicity and/or oncogenicity studies were conducted in rats, mice, and dogs with the insect repellent DEET. DEET was mixed in the diet and administered to CD rats for two years at concentrations that corresponded to dosage levels of 10, 30 or 100 mg/kg/day for males and 30, 100, or 400 mg/kg/day for females; to CD-1 mice for 18 months at dosage levels of 250, 500, or 1000 mg/kg/day; and to dogs for one year, via gelatin capsules, at dosage levels of 30, 100, or 400 mg/kg/day. In the rodent studies, each group consisted of 60 animals of each sex, and two concurrent independent control groups, each containing 60 animals/sex were included in each study. Each group in the dog study consisted of four male and four female dogs and one control group was included in the study. Treatment-related effects were observed at the highest dose level in all three studies. For rats, the effects included decreases in body weight and food consumption and an increase in serum cholesterol in females only. In mice, the effects observed were decreases in body weight and food consumption in both sexes. The effects observed in dogs included increased incidences of emesis and ptyalism, and levels of transient reduction in hemoglobin and hematocrit, increased alkaline phosphatase (males only), decreased cholesterol, and increased potassium. One male dog in the high-dose group also exhibited ataxia, tremors, abnormal head movements, and/or convulsions on several occasions during the study. The highest no- observed-effect levels (NO-ELs) for rats, mice and dogs were determined to be 100, 500, and 100 mg/kg/day, respectively. No specific target organ toxicity or oncogenicity was observed in any of the studies.   相似文献   
79.
80.
Ultrasound examination of the hydatic liver   总被引:9,自引:0,他引:9  
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