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The total experience (154 patients) with ball-valve (Starr-Edwards) replacement of the tricuspid valve, alone and in combination, through Dec. 31, 1971, at the Mayo Clinic is reviewed. The early mortality rate with isolated tricuspid replacement was twice that for tricuspid replacement combined with replacement of other valves. Among patients receiving three valves, those with "functional' tricuspid insufficiency and those who were in New York Heart Association (N.Y.H.A.) Class IV preoperatively had a higher early mortality rate. The early mortality rate for the total group was 28%. Of those surviving tricuspid plus mitral valve replacement, 70% were alive at 3 years; at latest follow-up, 94% of those surviving were functionally improved. Of those surviving triple valve replacement, 56% were alive at 3 years; at latest follow-up, 93% of those surviving were functionally improved. Previous cardiac surgery with residual tricuspid valve dysfunction and severe disability, as judged by N.Y.H.A. class, influenced the outcome adversely. The experience reported here provides a standard against which never prostheses can be compared.  相似文献   
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A major gene controlling warfarin-resistance in the house mouse.   总被引:4,自引:0,他引:4  
The spread of a "cream" mutant in a wild population of house mice is reported. The hypothesis that the gene responsible for the colour, extreme chinchilla, ce, has spread because of linkage with a major gene for warfarin-resistance, is tested by a linkage backcross. The results prove that a major gene does exist, that it is very closely linked with frizzy, fr, in chromosome 7, which in turn is linked with ce, that it is fully dominant in females at 4 months of age, and that its partial dominance in males is under the control of modifiers. The symbol War is proposed for the gene. Its position in chromosome 7 is analagous with the position of the resistant gene, Rw2, in the rat in the analagous chromosome. The adaptive significance of the finding is discussed, as also are reports of certain other mutants in wild populations of mice.  相似文献   
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OBJECTIVE: Point mutations in mitochondrial DNA (mtDNA) are one mechanism that could explain the apparent excess maternal transmission of bipolar affective disorder observed in some families. The authors sequenced the mtDNA from probands with bipolar disorder and tested nucleotide variants for association with the disorder. METHOD: The entire 16.5 kilobase mitochondrial genome was sequenced in nine unrelated probands selected from large pedigrees with exclusively maternal transmission of bipolar affective disorder. Compared to a reference sequence, variants were detected at 107 nucleotide positions. Fifteen variants of possible pathogenic significance were selected for further study. These variants were assayed in 93 unrelated probands with bipolar I, bipolar II, or schizoaffective-manic disorder and 63 comparison subjects, all of whom were classified into the major groups comprising the European mtDNA haplotype structure (haplogroups).RESULTS: The major European haplogroups were represented at the expected frequencies among both probands and comparison subjects. There was no significant difference between probands and comparison subjects in the frequency of any variant, although odds ratios >2 or <0.5 were observed for four variants. Frequencies of these four variants were similar in probands and haplogroup-matched comparison subjects. The results of all comparisons were essentially unchanged when probands from families with an apparently paternal transmission pattern were excluded.CONCLUSIONS: The results demonstrate that bipolar affective disorder occurs across all of the major European mtDNA haplogroups but do not reveal any point mutations that explain excess maternal transmission of the disorder.  相似文献   
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Within the context of a post-acute rehabilitation setting, association and agreement between results from the Neurobehavioural Cognitive Status Examination (NCSE) and from the neuropsychological (NP) evaluation are examined. All participants (n = 48) had sustained a severe traumatic brain injury and NCSE testing preceded NP testing by an average of 1 month. A significant relationship and fair classification agreement (i.e. presence or absence of cognitive impairment) was found between the overall results from NCSE and NP evaluation. Significant relationships were also observed between most NCSE subtests and paired NP tests thought to be assessing the same cognitive domains. However, the classification agreement (i.e. the presence or absence of deficient performance) between most NCSE subtests and paired NP tests was poor. The findings are discussed from the standpoint of individual treatment planning.  相似文献   
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PURPOSE: Dissemination of recommended therapies for non-small-cell lung cancer (NSCLC) have not been described comprehensively. We report the patterns of initial therapy focusing on the investigation of differences in receipt of recommended therapies according to multiple clinical and nonclinical patient characteristics. METHODS: A population-based random sample of newly diagnosed NSCLC patients diagnosed in 10 separate geographic areas was collected in 1996 (n = 898). Data were obtained from medical records. Multiple logistic regression was used to assess the use of recommended therapies. RESULTS: Overall, 52% of NSCLC patients received recommended therapy. Approximately 69%, 48%, and 41% of patients with stages I and II, III, or IV NSCLC received recommended therapy, respectively. For all stages combined, the use of recommended therapy was significantly inversely associated with age and stage at diagnosis. Recommended therapy also was more common in white versus black patients, and in married versus single patients. Stage-specific analyses revealed a significant decline in the use of recommended surgery with increasing age at diagnosis for early-stage NSCLC only, and a significantly lower use of recommended therapy (primarily chemoradiotherapy) for stage III black and Hispanic patients compared with white patients. CONCLUSION: The overall use of recommended therapies for NSCLC is low. Large variations exist in the use of such therapies according to age, race or ethnicity, and marital status. Research combining medical record reviews with other sources of data is needed to better understand the contributions of both patient preferences and physician judgment to these treatment variations.  相似文献   
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