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With the recent advent of accurate orbital volume assessment by computed tomography, a retrospective analysis was made of 31 patients with 'pure' blowout fracture of the orbital floor, managed either surgically or conservatively, to determine whether orbital volume measurement could provide an additional parameter of use in the management of such fractures. There was a significant difference in orbital volume discrepancy between patients managed surgically or conservatively suggesting that this investigation may be of use in decision making on surgical intervention in patients with orbital blowout fractures.  相似文献   
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OBJECTIVE: The objective of this review was to evaluate the clinical and research literature on professionally-led support groups for cancer patients and to propose an approach that would address patients' needs from diagnosis through survivorship. METHOD: Computerized and manual searches, including Medline and Psychlit searches, were completed for reviews of the literature. Twelve research studies were identified that met our criteria for in-depth review. A clinical model emerged from discussions of an oncology study group based on theoretical formulations and clinical experience with oncology patients. RESULTS: We found that recent research suggests that professionally-led support groups are increasing in number and that participation in such groups seems to enhance patients' quality, and possibly even quantity, of survival. Despite this, little effort has been made to determine what type of group may be appropriate for which patients and when in their course of care. CONCLUSIONS: If psychosocial intervention, in the form of professionally-led support groups for cancer patients, is to be more effective, it should be guided by a model which takes into consideration the changing needs and concerns of patients over the course of illness and, in many cases, recovery. The authors present an outline delineating what such a model might entail.  相似文献   
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During a recent attempt to produce solid forms of water-soluble, sulphonated reactive dye samples with low electrolyte content, it was found that salting-out of such dyes with sodium thiocyanate dihydrate and subsequent washing with acetone gave a product with very low content of inorganic salts. A readily soluble solid of high tinctorial strength was produced.  相似文献   
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OBJECTIVE: To identify clinical signs, physical examination findings, results of diagnostic tests, treatments administered, and clinical outcome of neonatal foals with enterocolitis associated with Clostridium perfringens infection. DESIGN: Retrospective study. ANIMALS: 54 neonatal foals. RESULTS: Most foals had acute onset of obtunded mentation, colic, or diarrhea and developed leukopenia, neutropenia, an abnormally high number of band neutrophils, toxic WBC, and hypoproteinemia within 24 hours after admission, despite high serum IgG concentrations (> 800 mg/dl). Abdominocentesis and abdominal radiography of some foals revealed exudative peritonitis and gaseous distention of the small and large intestine, respectively. Cytologic examination of feces revealed spores or gram-positive rods in 8 of 10 foals. The most common genotypes of C perfringens isolates were type A and C, alone or in combination. Treatment did not alter mortality rate for most foals that had a positive culture for C perfringens type C. Of 54 foals, 29 (54%) that had C perfringens-associated enterocolitis died. Foals that had a culture that yielded C perfringens had higher sepsis scores, IgG concentrations, and mortality rates, compared with the overall hospital population of neonatal foals. CLINICAL IMPLICATIONS: Foals less than 7 days old that have enterocolitis associated with C perfringens infections, especially type C, have a guarded prognosis. Cytologic examination of feces to determine spore counts and detect rods may be a means for early identification of C perfringens infections. Polymerase chain reaction assays to determine genotype are important for designing preventive treatment regimens.  相似文献   
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We have sequenced the NIb coding region of sugarcane mosaic potyvirus strain SC (SCMV-SC) and eight field isolates of SCMV from Australia. This region comprised 1563 nucleotides and encoded a putative protein of 521 amino acids containing the consensus motif GDD. The protease cleavage sites between the NIa/NIb and the NIb/coat protein were found to be Q/C and Q/A, respectively. The SCMV sequences were most similar to sorghum mosaic potyvirus with identities of 70% and 78% at the nucleotide and amino acid levels, respectively. When the sequences were compared to each other, there was a maximum of 3.3% variation between isolates at the nucleotide level and a maximum of 0.8% at the amino acid level. Phylogenetic analysis of the sequences indicated the field isolates were grouped according to their geographical location. The SCMV sequence with most homology to all other isolates has been selected to generate constructs for replicase-mediated resistance.  相似文献   
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BACKGROUND: The association of serum lipids with coronary heart disease has been studied extensively in middle-aged men and, to a lesser extent, in similar women. Less well defined are lipid variables predictive of CHD in individuals of age > or = 60 years. METHODS AND RESULTS: The Systolic Hypertension in the Elderly Program recruited 4736 persons (mean age, 72 years; 14% were black; and 43% were men). Mean systolic and diastolic blood pressures were 170 and 77 mm Hg, respectively. Baseline mean total cholesterol was 6.11 mmol/L (236 mg/dL); HDL cholesterol, 1.39 mmol/L (54 mg/dL); and non-HDL cholesterol, 4.72 mmol/L (182 mg/dL). Triglyceride levels were 1.62 mmol/L (144 mg/dL) for fasting participants and 1.78 mmol/L for the total group. LDL cholesterol, estimated in fasting samples with triglycerides of < 4.52 mmol/L, averaged 3.98 mmol/L (154 mg/dL). Mean follow-up was 4.5 years. In multivariate Cox regression analyses, baseline total, non-HDL, and LDL cholesterol levels and the ratios of total, non-HDL, and LDL to HDL cholesterol were significantly related to CHD incidence. HDL cholesterol and triglycerides were not significant in these analyses. In fasting participants with triglyceride levels of < 4.52 mmol/L, a 1.03 mmol/L (40 mg/dL) higher baseline total, non-HDL, or LDL cholesterol was associated with a 30% to 35% higher CHD event rate. CONCLUSIONS: The results of this study support the concept that serum lipids are CHD risk factors in older Americans.  相似文献   
70.
The effect of external calcium concentration ([Ca2+]o) on membrane potential-dependent calcium signals in isolated tiger salamander rod and cone photoreceptor inner segments was investigated with patch-clamp and calcium imaging techniques. Mild depolarizations led to increases in intracellular Ca2+ levels ([Ca2+]i) that were smaller when [Ca2+]o was elevated to 10 mM than when it was 3 mM, even though maximum Ca2+ conductance increased 30% with the increase in [Ca2+]o. When external calcium was lowered to 1 mM [Ca2+]o, maximum Ca2+ conductance was reduced, as expected, but the mild depolarization-induced increase in [Ca2+]i was larger than in 3 mM [Ca2+]o. In contrast, when photoreceptors were strongly depolarized, the increase in [Ca2+]i was less when [Ca2+]o was reduced. An explanation for these observations comes from an assessment of Ca2+ channel gating in voltage-clamped photoreceptors under changing conditions of [Ca2+]o. Although Ca2+ conductance increased with increasing [Ca2+]o, surface charge effects dictated large shifts in the voltage dependence of Ca2+ channel gating. Relative to the control condition (3 mM [Ca2+]o), 10 mM [Ca2+]o shifted Ca2+ channel activation 8 mV positive, reducing channel open probability over a broad range of potentials. Reducing [Ca2+]o to 1 mM reduced Ca2+ conductance but shifted Ca2+ channel activation negative by 6 mV. Thus the intracellular calcium signals reflect a balance between competing changes in gating and permeation of Ca2+ channels mediated by [Ca2+]o. In mildly depolarized cells, the [Ca2+]o-induced changes in Ca2+ channel activation proved stronger than the [Ca2+]o-induced changes in conductance. In response to the larger depolarizations caused by 80 mM [K+]o, the opposite is true, with conductance changes dominating the effects on channel activation.  相似文献   
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