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1.
The epidemiologic necropsy for abdominal aortic aneurysm   总被引:1,自引:0,他引:1  
M J McFarlane 《JAMA》1991,265(16):2085-2088
The epidemiologic necropsy measures the occurrence of unsuspected disease through the examination of necropsy records. The estimates of unsuspected disease should approximate what occurs in the living population. The necropsy records of the University of Kansas Medical Center (Kansas City) from 1950 to 1984 were examined for the occurrence rate of abdominal aortic aneurysms. Each adult patient was categorized as (1) without abdominal aortic aneurysm, (2) abdominal aortic aneurysm discovered as a necropsy surprise, or (3) abdominal aortic aneurysm diagnosed or suspected during life. Necropsy detection rates of unsuspected abdominal aortic aneurysms were compared with those found in five published screening surveys. The necropsy detection rate in men was 81 (0.019) of 4155 and was 28 (0.009) of 3142 in women, a difference that was statistically significant. When the necropsy series was adjusted to reflect the same demographic composition as the screening surveys, the results from necropsy and screening were statistically similar. In particular, two surveys from the United Kingdom showed screening detection rates among white men of 0.072 compared with a necropsy detection rate of 0.058. These results further support the use of the epidemiologic necropsy as a research tool for estimating the reservoir of disease in the population.  相似文献   
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BACKGROUND: Developments in accelerator mass spectrometry (AMS) now permit the determination of femtogram amounts of 26Al in blood and in various tissues with good precision and free of external contamination. METHODS: In the present study we used trace quantities of 26Al to investigate the intestinal absorption and compartmentalization of aluminium in rats with renal failure (Nx, 5/6 nephrectomy) and in pair- fed controls (C). Single oral doses of 20 ng 26Al were administered to six animals in each group and, subsequently, 24-h post-load 26Al was analysed in serum, urine, bone, liver, and spleen by means of AMS. RESULTS: Serum concentrations of 26Al were significantly lower in uraemic rats compared to controls, whereas urinary excretion was comparable (Nx, 7.11 +/- 5.78 pg/day vs C, 9.46 +/- 6.10 pg/day), suggesting a higher fraction of ultrafiltrable serum 26Al in uraemia. The target tissues of cellular transferrin-mediated 26Al uptake, liver and spleen, tended to show a larger degree of aluminium accumulation in controls (0.26 +/- 0.31 pg/g vs Nx, 0.14 +/- 0.10 pg/g and 0.37 +/- 0.27 pg/g vs Nx, 0.25 +/- 0.27 pg/g respectively). In contrast, in bone, a site of extracellular aluminium deposition, 26Al concentrations were more elevated in uraemia (1.22 +/- 0.59 pg/g vs C: 0.68 +/- 0.30 pg/g). Estimated total 26Al accumulation in all measured target tissues was significantly higher in uraemic rats (28.15 +/- 9.90 pg vs C: 17.03 +/- 7.03 pg) and total recovery of 26Al from tissue and urine was 26.58 +/- 6.74 pg in controls and 35.75 +/- 7.03 pg in uraemic animals, suggesting a fractional absorption of 0.133% and 0.175% respectively. CONCLUSIONS: Our data suggest that fractional absorption from a dietary level dose of 26Al is about 0.13%. Compartmentalization occurs in transferrin-dependent target tissues such as liver and spleen; however, in quantitative terms extracellular deposition in bone is more important. Uraemia has a significant effect on the intestinal absorption and compartmentalization of aluminium. It enhances fractional absorption and increases subsequent extracellular deposition of aluminium in bone. However, at the same time uraemia does not increase transferrin-dependent cellular accumulation of aluminium in liver and spleen.   相似文献   
4.
Isoflurane for removal of chest drains after cardiac surgery   总被引:2,自引:0,他引:2  
Thirty-five patients who had undergone uncomplicated cardiac surgery were randomly allocated to receive either Entonox or isoflurane 0.25% in Entonox as inhalational analgesia for the removal of their two chest drains. The gases were presented premixed in high-pressure cylinders and were self-administered by means of a demand valve. The removal of the second drain was more painful than the first but that pain was better controlled by isoflurane 0.25% in Entonox than by Entonox alone.  相似文献   
5.
The relationship between internal jugular vein diameter as measured with an ultrasound imaging machine (SiteRite, Dymax) and external jugular vein diameter was studied in 50 anaesthetised patients undergoing elective cardiac surgery. There was an inverse correlation between external jugular vein diameter and internal jugular vein diameter ( r  = −0.47, p < 0.001). All patients with an external jugular vein diameter of 7 mm or greater had an internal jugular vein diameter of less than 15 mm. No patient with an external jugular vein diameter of less than 7 mm had an internal jugular vein diameter of less than 20 mm. No other patient dimension (height, weight, body mass index, neck circumference) predicted internal jugular vein size. These results suggest that a large external jugular vein (i.e. 7 mm or greater in external diameter) may be associated with a small internal jugular vein. A size 5.0-mm internal diameter tracheal tube may be used to provide a rapid assessment of external jugular vein diameter.  相似文献   
6.
Battered and pregnant: a prevalence study.   总被引:16,自引:9,他引:7       下载免费PDF全文
We interviewed 290 pregnant women randomly selected from public and private prenatal clinics, 80 per cent of whom were at least five months pregnant (ages 18-43, 42 per cent Latino, 22 per cent Black). Twenty-four women reported physical battering during this pregnancy (44 reported physical battering before the current pregnancy). Eight of the 24 pregnant women had sought medical treatment for injuries sustained; none reported having been assessed by prenatal care providers for abuse.  相似文献   
7.
Hydranencephaly is defined as the replacement of a previously normal brain, in whole or in part, by membranous fluid-filled sacs. The etiology is not well understood, and the time course of development is unknown. Fifteen ovine fetuses were chronically cannulated and had both carotid arteries ligated at 100 days of gestation (term is 145–150 days). They were killed at 1 (n = 4), 2 (n = 6) and 4 (n = 5) weeks post-surgery, and the findings compared with those of 25 age-matched controls. By 2 weeks post-surgery the entire cerebral hemispheres and diencephalon had been replaced by fluid closely resembling cerebrospinal fluid. The choroid plexus, pituitary and brain stem remained outwardly normal, but the cerebellum showed signs of damage. Fetuses maintained normal values for blood gases and hematocrit up to 4 weeks post-surgery, and grew normally. Light microscopy of the brain stem showed significant losses of cell populations in the medulla by 4 weeks. Vascular casting and acute blood flow studies in an additional group of fetuses showed that the entire brain was perfused via the vertebral-occipital anastomosis immediately after acute bilateral carotid clamping, but that the blood flow rate was insufficient to maintain adequate oxygen delivery. Received: 4 August 1995 / Revised, accepted: 30 November 1995  相似文献   
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(1) Freshly dispersed cells from four Burkitt's lymphoma biopsies, and three `lymphoblast' cell lines (OB2, OB3 and OB6) derived from the tumour were tested for capacity to synthesize immunoglobulins in vitro.

Using labelled amino acid incorporation, electrophoretic, radio-immunoelectrophoretic and ultracentrifugation techniques, it was possible to demonstrate the release of labelled proteins with antigenic characteristics of immunoglobulins by all four biopsy samples, and the two cell lines tested by these techniques. Newly synthesized labelled proteins were demonstrable in the culture medium within 1 hour of incubation.

In a separate series of experiments, absorption and immunodiffusion techniques were used in the characterization of proteins synthesized by two cell lines (OB2 and OB3) growing as healthy continuous cultures.

(2) Freshly isolated cells from Burkitt's lymphoma are capable of immunoglobulin synthesis in vitro. Cells from all four fresh biopsy materials produced IgG. One cell line (OB2) produced IgG and type-κ light chains, while OB6 cell line produced IgA. Immunoglobulin synthesis was not detected in OB3 cell line by immunodiffusion technique.

(3) Cells from each biopsy specimen or cell line produced not more than one type of immunoglobulin, although there was a wide variation in the sedimentation coefficient of the protein molecules synthesized by one (OB6) and presumably all other cell lines.

  相似文献   
10.
A method is described for purifying malarial antigen from human brain. The antigen appears to be highly specific for malarial antibodies. On double diffusion in agar gel a precipitin reaction was produced only with sera from persons with malarial parasites in their peripheral blood and those with high malarial fluorescent antibody titre. No precipitin lines were formed with sera from persons who were known to be free from malarial infection.  相似文献   
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