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71.
BACKGROUND: When managing hypertension, the assessment of the absolute risk of a cardiovascular' event is now advocated as the most accurate way in which the risks and benefits of anti-hypertensive therapy should be judged. Most studies that have examined control of hypertension have relied solely on the blood pressure level attained after treatment, with no measurement of the likely absolute risk in individual patients. AIM: To assess control of hypertension by quantifying the 10-year absolute risk of cardiovascular disease in patients treated by their general practitioners, and to assess which risk factors are associated with uncontrolled hypertension in this group of patients. METHOD: A cross-sectional study was made of patients on drug treatment for hypertension in 18 Oxfordshire general practices subscribing to the VAMP (value-added medical products) computer system. The absolute risk of suffering a cardiovascular event in the following 10 years was measured according to each individual's risk factor profile. Factors associated with uncontrolled hypertension were ascertained using multiple logistic regression analysis. RESULTS: Overall, 40.9% (37.6% to 44.1%) of the hypertensive population had an absolute risk exceeding 20% of having a cardiovascular event in the following 10 years. The distribution of risk factors varies throughout the population. A higher blood pressure reading was strongly associated with an increased likelihood of high absolute risk, but high blood pressure readings in individual patients did not necessarily equate to a high absolute risk. The factors independently associated with uncontrolled hypertension were age, sex, past history of stroke, ischaemic heart disease and transient ischaemic attack, a body mass index greater than 30, diabetes, and current smoking. CONCLUSIONS: Absolute risk assessment maximizes the risk-benefit ratio in treated hypertensive patients. Individual control and management requires multifactorial assessment and management. Treatment of hypertension according to blood pressure reading alone is not a reliable way of reducing the absolute risk of cardiovascular disease.  相似文献   
72.
Control of protein intake was studied in young rats that were allowed to choose between either protein-free and 55% casein diets or 15% and 55% casein diets. Animals on the protein-free vs. 55% casein regimen exhibited a lower weight gain, a lower cumulative energy intake and a greater cumulative total protein intake during the 13-day study compared to rats selecting between 15% and 55% casein. The daily average proportion of total food selected as casein by animals choosing between protein-free and 55% casein diets increased from 15% to 38% during the course of the study. In contrast, rats choosing between 15% and 55% casein chose 18-22% of total food as protein throughout the entire study. Long-term protein intake or protein selection did not correlate significantly with whole-brain contents of 5-HT or 5-HIAA. Our results suggest that protein intake is not regulated at a constant proportion of total calories, but is controlled between a minimum level that will support rapid growth and a maximum that, if exceeded, would require the animal to undergo substantial metabolic adaptation. The mechanism controlling protein selection may involve diet-induced changes in the brain content of total free indispensable amino acids.  相似文献   
73.
Complement studies in membranoproliferative glomerulonephritis   总被引:1,自引:2,他引:1       下载免费PDF全文
Detailed studies of the complement system were carried out in fifteen patients with membranoproliferative glomerulonephritis. The findings of reduced levels of C3 and C7 and of circulating breakdown products of C3 in fresh plasma suggested in vivo complement activation. Low C3 levels were associated with the presence of a serum factor (the C3 nephritic factor C3NeF) which was capable of breaking down C3 in normal serum in vitro. Metabolic studies using radioactive iodine labelled C3 showed no evidence of accelerated in vivo breakdown of parenterally administered C3 suggesting that hypocomplementaemia is either maintained by diminished C3 synthesis or that accelerated catabolism is occurring in a pool that does not freely exchange with parenterally given C3. The C3 nephritic factor has so far only been identified in patients with membranoproliferative nephritis and is therefore of major diagnostic significance in patients with glomerular disease.  相似文献   
74.
Summary Lipoprotein(a), as an atherogenic particle, represents an independent risk factor for coronary heart disease. In the present study the morphological distribution of apoprotein (a) and apoprotein B within the arterial wall is described. Apoprotein B, a constituent of very low-density lipoprotein, low-density lipoprotein and lipoprotein(a) has previously been demonstrated in atheromatous lesions. Lipoprotein(a) possesses an additional protein, designated apoprotein (a). Autopsy material (n=74) from the left coronary artery and from the thoracic aorta has been examined by means of immunohistochemistry and both apoprotein (a) and apoprotein B were detected, primarily associated with the extracellular matrix and accumulating in lesions in the arterial wall. The staining pattern for both antigens was almost always found to be congruent, suggesting that the detection of (a)-antigen has to be attributed at least in part to the presence of lipoprotein(a). It is concluded that both low-density lipoprotein and lipoprotein(a) have an important role in the pathogenesis of atherosclerosis.  相似文献   
75.
A sandwich enzyme immunosorbent assay (EIA) using a mixture of mouse monoclonal antibodies for antigen capture and polyclonal hyperimmune rabbit anti-Ebola virus serum for antigen detection was developed and evaluated on the tissues of monkeys naturally or experimentally infected with strains of Ebola viruses. When compared with virus isolation, the antigen detection EIA was both sensitive and specific: 44 of 45 (97.7%) liver homogenates and 38 of 41 (92.7%) spleen homogenates that were culture positive and tested by both techniques were positive for viral antigen, while 85 of 87 (97.7%) culture-negative liver homogenates and 66 of 66 culture-negative spleen homogenates were found to be antigen negative. The assay, initially developed to detect antigens of prototype African strains of Ebola virus, reliably detected related strains of Ebola virus found during two recent outbreaks of Ebola virus infection among imported, quarantined Macaca fascicularis monkeys in the United States. The assay allows economical and rapid testing of large numbers of tissue specimens. Antigen was found in homogenates of spleen and liver and in serum.  相似文献   
76.
Polycystin-1 is a novel protein predicted to be a large membrane-spanning glycoprotein with an extracellular N-terminus and an intracellular C-terminus, harboring several structural motifs. To study the subcellular localization, antibodies raised against various domains of polycystin-1 and against specific adhesion complex proteins were used for two-color immunofluorescence staining. In Madine Darby canine kidney (MDCK) cells, polycystin-1 was detected in the cytoplasm as well as co-localizing with desmosomes, but not with tight or adherens junctions. Using confocal laser scanning and immunoelectron microscopy we confirmed the desmosomal localization. By performing a calcium switch experiment, we demonstrated the sequential reassembly of tight junctions, subsequently adherens junctions and finally desmosomes. Polycystin-1 only stained the membrane after incorporation of desmoplakin into the desmosomes, suggesting that membrane-bound polycystin-1 may be important for cellular signaling or cell adhesion, but not for the assembly of adhesion complexes.  相似文献   
77.
78.
This case report describes a 4 year old boy with the unique triad of lipomatous myelomeningocele, congenital hypothyroidism secondary to thyroid agenesis, and sensorineural deafness. While associations between deafness and abnormal thyroid function and deafness and sacral lipoma have previously been described, the constellation of findings in this patient has not been reported.  相似文献   
79.
Since identification of the genes mutated in patients with Autosomal Dominant Polycystic Kidney Disease, PKD1 and PKD2, a large number of different germ line mutations in both genes have been found by conventional PCR-based mutation detection methods. Nevertheless, in approximately 40% of the PKD1 families the disease-causing mutation remains to be elucidated. Complex germ line rearrangements are often not detectable by these standard diagnostic techniques. To detect large deletions in the PKD1 gene we performed Field Inversion Gel Electrophoresis (FIGE) followed by Southern blot analysis with probes selected in the unique and in the reiterated region of this gene. Our analysis revealed 4 deletions in 125 patients, indicating that large deletions in PKD1 are rare. Likely, patients with a deletion that also affects the neighbouring Tuberous Sclerosis Complex 2 (TSC2) gene will be diagnosed as patients with tuberous sclerosis. It was speculated that the exceptional polypyrimidine tract located in intron 21 and the small tract in intron 22, might play a role in the pathogenesis of ADPKD. Since this region is extremely difficult to amplify by PCR, we analysed the 5.8 kb BamHI fragment that contains the polypyrimidine tracts. We did not observe a disease-linked alteration although we detected two different rare variants either in PKD1 or in one of its homologues.  相似文献   
80.
The acid phosphatase (ACP1) locus codes for a low molecular weight protein tyrosine phosphatase (LMPTP) that is found ubiquitously in human tissues. The *A allele of the ACP1 gene is associated with lower total enzymatic activity than the *B and *C alleles. An association between the *A allele and extreme values of body-mass-index (BMI) and dyslipidemia has previously been described in several samples of obese subjects from the Italian population. In the present study, we investigated the relationship between ACP1 *A allele genotypes (*A/*A, *A/*B, and *A/*C) and non-*A allele genotypes (*B/*B, *B/*C, and *C/*C) and metabolic variables in 277 Caucasian post-menopausal subjects consisting of 82 non-obese subjects (BMI/=35) subjects. ACP1 genotypes were found to be significantly associated with total cholesterol (p相似文献   
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