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91.

Hyperoxia (>95% oxygen) in rats caused an increase in lung weight and an accumulation of fluid in the thorax. The mean lung wet weight of air-breathing controls at 60 h was 1.2±0.01 g, and that of vehicle-treated, oxygen-exposed animals was 2.45±0.05 g. Treatment with the 21-aminosteroid U-74389F, 3, 10, and 30 mg/kg twice daily throughout oxygen exposure, produced 8, 42, and 18% inhibition of the oxygen-induced increase in lung weight, respectively. However, U-74389F did not inhibit the hyperoxia-induced accumulation of neutrophils in bronchoalveolar lavage fluid.

No pleural fluid could be aspirated from the thorax of air-breathing controls. The volume of pleural fluid in oxygen-exposed, vehicle-treated animals and animals treated with 3, 10, and 30 mg/kg U-74389F b.i.d. was 6.5±0.9, 2.6±0.6, 0.8±0.3, and 1.3±0.5 ml, respectively.

U-74389F or its biologs are of potential value for the treatment of lung diseases in which oxidant damage has been implicated.

  相似文献   
92.
VHL disease is a dominantly inherited familial cancer syndromewith variable expression and age-dependent penetrance. The diagnosisof isolated cases is often delayed compared with familial cases,and estimates of the new mutation rate have varied more than20-fold. To investigate the frequency and origin of de novoVHL gene mutations we have analysed: (i) families with identicalmutations to determine if there is a common haplotype, and (ii)apparent new mutation cases to determine whether the clinicaldiagnosis of such cases is reliable and to define the parentalorigin of de novo VHL gene mutations. Haplotyping of 12 VHLmutations occurring in two or more families (total 42 kindreds)revealed that for most mutations there was no evidence of afounder effect. A marked bias for a paternal origin of new mutationshas been reported in other familial cancer syndromes such asneurofibromatosis type 1 (NF1), multiple endocrine neoplasia(MEN) 2B and bilateral retinoblastoma, but it is unclear whetherthis bias results from a greater susceptibility for mutagenesisduring male gametogenesis because of the larger number of celldivisions compared with that in oogenesis, or from genomic imprintingeffects. Analysis of 13 de novo VHL mutations in which the parentof origin could be established, showed no evidence for a biasfor a paternal origin (seven paternal, six maternal), and differedsignificantly from that reported in NF1, MEN2B and bilateralretinoblastoma. This result demonstrates that an increased susceptibilityto paternal allele mutation is not a universal finding in autosomalgenetic diseases and that the origin of new mutations may beinfluenced by both genomic imprinting effects and the increasednumber of cell divisions in spermatogenesis compared with oogenesis.  相似文献   
93.
While much has been written about the benefits of personal continuity of care there has been little research about the views of patients. In this cross sectional study 111 patients from three group practices (one of which ran a personal list system) were interviewed at home within a week of consulting a general practitioner. Patients were selected randomly from a systematic series of consulting sessions and a semi-structured interview was administered. Patients receiving more personal continuity of care were likely to be older, to have booked their most recent appointment further in advance, to desire personal continuity of care, to have an external health locus of control and to have a lower extroversion score. In the practice with a personal list, patients had a high level of continuity of care, were satisfied and showed little interest in having a choice of doctor. In the combined list practices patients valued their choice of doctor but often could not exercise it enough and they were more critical. They made more suggestions for change than those in the practice with a personal list system, mostly about receptionists and appointments. It is concluded that most patients like to see the same doctor, but they may not be willing to wait two days for this if there is a quicker option. It may be difficult to deliver both personal continuity of care and choice in group practice.  相似文献   
94.
BACKGROUND: Studies suggest that nasal treatment might influence lower airway symptoms and function in patients with comorbid rhinitis and asthma. We investigated the effect of intranasal, inhaled corticosteroid or the combination of both in patients with both pollen-induced rhinitis and asthma. METHODS: A total of 262 patients were randomized to 6 weeks' treatment with intranasal fluticasone propionate (INFP) 200 microg o.d., inhaled fluticasone propionate (IHFP) 250 microg b.i.d., their combination, or intranasal or inhaled placebo, in a multicentre, double-blind, parallel-group study. Treatment was started 2 weeks prior to the pollen season and patients recorded their nasal and bronchial symptoms twice daily. Before and after 4 and 6 weeks' treatment, the patients were assessed for lung function, methacholine responsiveness, and induced sputum cell counts. RESULTS: Intranasal fluticasone propionate significantly increased the percentages of patients reporting no nasal blockage, sneezing, or rhinorrhoea during the pollen season, compared with IHFP or intranasal or inhaled placebo. In contrast, only IHFP significantly improved morning peak-flow, forced expiratory volume in 1 second (FEV1) and methacholine PD20, and the seasonal increase in the sputum eosinophils and methacholine responsiveness. CONCLUSIONS: In patients with pollen-induced rhinitis and asthma, the combination of intranasal and IHFP is needed to control the seasonal increase in nasal and asthmatic symptoms.  相似文献   
95.
This first best practice review examines four series of common primary care questions in laboratory medicine, namely: (i) measurement and monitoring of cholesterol and of liver and muscle enzymes in patients in the context of lipid lowering drugs, (ii) diagnosis and monitoring of vitamin B12/folate deficiency, (iii) investigation and monitoring of paraprotein bands in blood, and (iv) management of Helicobacter pylori infection. The review is presented in a question-answer format, referenced for each question series. The recommendations represent a précis of guidance found using a standardised literature search of national and international guidance notes, consensus statements, health policy documents, and evidence based medicine reviews, supplemented by MEDLINE EMBASE searches to identify relevant primary research documents. They are not standards but form a guide to be set in the clinical context. Most are consensus rather than evidence based. They will be updated periodically to take account of new information.  相似文献   
96.
Pseudoxanthoma elasticum (PXE) is a systemic heritable disorder that affects the elastic tissue in the skin, eye, and cardiovascular system. Mutations in the ABCC6 gene cause PXE. We performed a mutation screen in ABCC6 using haplotype analysis in conjunction with direct sequencing to achieve a mutation detection rate of 97%. This screen consisted of 170 PXE chromosomes in 81 families, and detected 59 distinct mutations (32 missense, eight nonsense, and six likely splice-site point mutations; one small insertion; and seven small and five large deletions). Forty-three of these mutations are novel variants, which increases the total number of PXE mutations to 121. While most mutations are rare, three nonsense mutations, a splice donor site mutation, and the large deletion comprising exons 23-29 (c.2996_4208del) were identified as relatively frequent PXE mutations at 26%, 5%, 3.5%, 3%, and 11%, respectively. Chromosomal haplotyping with two proximal and two distal polymorphic markers flanking ABCC6 demonstrated that most chromosomes that carry these relatively frequent PXE mutations have related haplotypes specific for these mutations, which suggests that these chromosomes originate from single founder mutations. The types of mutations found support loss-of-function as the molecular mechanism for the PXE phenotype. In 76 of the 81 families, the affected individuals were either homozygous for the same mutation or compound heterozygous for two mutations. In the remaining five families with one uncovered mutation, affected showed allelic compound heterozygosity for the cosegregating PXE haplotype. This demonstrates pseudo-dominance as the relevant inheritance mechanism, since disease transmission to the next generation always requires one mutant allelic variant from each parent. In contrast to other previous clinical and molecular claims, our results show evidence only for recessive PXE. This has profound consequences for the genetic counseling of families with PXE.  相似文献   
97.
L1 is a neural cell adhesion molecule mainly involved in axon guidance and neuronal migration during brain development. Mutations in the human L1 gene give rise to a complex clinical picture, with mental retardation, neurologic abnormalities and a variable degree of hydrocephalus. Recently, a transgenic mouse model with a targeted null mutation in the L1 gene was generated. These knockout (KO) mice show hypoplasia of the corticospinal tract. Here we have performed further studies of these KO mice including magnetic resonance imaging of the brain, neuropathological analysis and behavioral testing. The ventricular system was shown to be abnormal with dilatation of the lateral ventricles and the 4th ventricle, and an altered shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the KO mice is hypoplastic. Their exploratory behavior is characterized by stereotype peripheral circling reminiscent of that of rodents with induced cerebellar lesions.   相似文献   
98.
Hallam PJ, Mannucci P, Tripodi A, Bevan D, Laursen B, Tengborn L, Wacey A, Cooper DN. Three novel PROC gene lesions causing protein C deficiency. Clin Genet 1998: 54: 231–233. 0 Munksgaard, 1998
Missense mutations. three of them novel (Am210→Val, Asn248→ Ile, Ah355→Val), were found in the protein c ( PROC ) genes of 7 patients with inherited protein C deficiency associated with venous thrombosis. Comparison with the phenotypic effects of mutations in the analogous residues of factor IX causing hdernophilia B and the use of molecular modelling has provided explanations as to how these lesions might alter either the structure, function or secretion of the protein C molecules encoded.  相似文献   
99.
100.
Protecting confidential information disclosed to doctors has been one of the most important ethical traditions of the medical profession. However, the patient's right to such confidentiality is threatened because it is legally unclear how far ownership by Government of the paper on which NHS records are kept or of the computer system in which they are stored confers right of access.

We hope the medical profession will examine this problem urgently and offer some suggestions as to how patients' confidences can continue to be protected in the future.

  相似文献   
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