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Intrafamilial variation of the phenotype in Bardet-Biedl syndrome   总被引:3,自引:0,他引:3       下载免费PDF全文
AIMS—To describe the variation of the phenotype within families with several individuals with Bardet-Biedl syndrome.
METHODS—The phenotypes of affected siblings in 11 Scandinavian families were compared with two or more members who had at least three of the features: retinal dystrophy, polydactyly, obesity, hypogenitalism, and mental retardation. Individuals without retinal dystrophy were excluded.
RESULTS—Intrafamilial variation of expressivity of the features obesity, polydactyly, abnormal radiograms of the extremities, hypogenitalism, short stature, paraplegia, and dental abnormalities was found. The retinal dystrophy varied with respect to both the onset of symptoms and the course of the disease. The morphology of the fundus, however, was consistent within the families. The disorder showed statistically significant genetic linkage to the BBS4 locus on chromosome 15 in the affected siblings in two of the families, but the clinical features in these patients did not differ from the other cases of Bardet-Biedl syndrome.
CONCLUSION—Comparison of siblings with the Bardet-Biedl syndrome showed variation of the typical features. In addition, the course of retinal dystrophy varied. No distinctive clinical features were found to separate the BBS4 phenotype from the remaining patients.

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Occupational exposure to carcinogenic agents on the decks on six Norwegian crude oil tankers was examined in five harbors. The purpose of the study was to evaluate the need for improving the working environment on deck on these tankers. Technical arrangments and the work itself on the deck were observed during loading or unloading. Occupational monitoring was performed by active sampling of benzene, polyaromatic hydrocarbons, and some aldehydes. The crew answered a questionnaire concerning their work, use of protective equipment, and occurrence of acute symptoms. The levels of air-borne carcinogenic agents were low, probably due to closed loading systems on all tankers. However, the seamen reported discomfort during the work that may be related to other chemical agents in the cargo. The seamen were frequently painting with lead chromate paint without using personal protective equipment. This type of chemical exposure should be evaluated.  相似文献   
4.
The incidence of multiple sclerosis (MS) was studied in the county of Hordaland, western Norway. A significant increase in incidence in the period 1958-1987, a decline followed by a gradual increase in mean age at onset, geographic differences in time trends and a biphasic pattern revealed by a birth cohort analysis support the theory of real time-space fluctuations in the incidence of MS over time.  相似文献   
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OBJECTIVE: The final outcome of patients with small cell lung cancer (SCLC) is poor with an overall 5-year survival rate of less than 10%. Therefore, the question of surgery in patients with a technically-operable solitary tumor has been raised. The purpose of this study was to identify the proportion of patients with operable SCLC and to assess the prognosis of different treatment strategies. For patients who were operated, we compared the resection specimens from patients with more than 5-year survival with those with shorter survival to see whether the specimens belonged to different subclasses of SCLC. METHODS: In Norway all clinical and pathologic departments submit reports on cancer patients to the Cancer Registry. The Registry also has a law-regulated authority to collect supplemental information regarding diagnosis, treatment and outcome for all cancer patients from the hospitals in charge. All reports on patients diagnosed as having SCLC in limited disease or unknown stage during the time interval 1993-1999 were reviewed. Patients with a T2-tumor, in whom a pneumonectomy would have to be performed, were classified as potentially operable. Five-year relative survival was calculated for patients diagnosed in 1993-1997. RESULTS: During the actual period 2442 individuals with SCLC were identified. The majority was treated with conventional chemotherapy or concurrent chemoradiotherapy while 38 underwent surgical therapy. Following reclassification of 697 patients reported to have limited disease or unknown stage 180 were judged to be in stage I. In addition to the 38 resected patients 14 were considered fit for surgery technically and medically while 97 were found to be potentially operable treatment modalities apart from surgery yielded a 5-year survival rate <7%. For stage I (N=96) the rate was 11.3% in conventionally treated patients compared to 44.9% for those who underwent surgical resection. By pathological review of surgical specimens a diagnosis of SCLC was confirmed in all patients treated by surgery in the groups with long and short survival. CONCLUSION: This investigation demonstrates that patients with SCLC having a peripherally located tumor should be referred to surgery, as long time survival is far better than for conventionally treated patients.  相似文献   
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Haplotype analysis of the low density lipoprotein receptor (LDLR) gene was performed in Norwegian subjects heterozygous for familial hypercholesterolemia (FH). Southern blot analysis of genomic DNA, using an exon 18 specific probe and the restriction enzyme NcoI, showed that two out of 57 unrelated FH subjects had an abnormal 3.6 kb band. Further analyses revealed that this abnormal band was due to a 9.6 kb deletion that included exons 16 and 17. The 5' deletion breakpoint was after 245 bp of intron 15, and the 3' deletion breakpoint was in exon 18 after nucleotide 3390 of cDNA. Thus, both the membrane-spanning and cytoplasmatic domains of the receptor had been deleted. A polymerase chain reaction (PCR) method was developed to identify this deletion among other Norwegian FH subjects. As a result of this screening one additional subject was found out of 124 subjects screened. Thus, three out of 181 (1.7%) unrelated Norwegian FH subject possessed this deletion. The deletion was found on the same haplotype in the three unrelated subjects, suggesting a common mutagenic event. The deletion is identical to a deletion (FH-Helsinki) that is very common among Finnish FH subjects. However, it is not yet known whether the mutations evolved separately in the two countries.  相似文献   
8.
The response of human granulocytes to polystyrene latex beads of diameter 0.1–7 m was measured by luminol-dependent chemiluminescence. In all instances, the response to beads of 3–7 m was definitely higher than with smaller beads. In protein-free medium, the chemiluminescence response was slow compared to that of opsonized zymosan, and the highest response was only 9% of the response to opsonized zymosan. Scanning electron microscopy showed that granulocytes in suspension bound the particles, occasionally by extending rope-like protrusions. When the beads were coated with albumin, the chemiluminescence diminished to about 1/3 of that seen with uncoated beads; however, preincubating the beads in serum led to a large increase with beads of 1.1 m (to 25% of the maximal response to opsonized zymosan) and 3.19 m (to 42%), but with the smallest beads, no increase was noted. "Priming" of the cells with tumor necrosis factor- caused a further increase with serum-coated beads. When uncoated beads of 1.1 m were tested with "primed" cells, there was an increase of 6 times in the chemiluminescence compared to un-"primed" cells.  相似文献   
9.
The isologous antiidiotypic response in BALB/c mice to immunization with the DNP-binding IgA myeloma protein, MOPC 315, alters the expression of the anti-DNP antibody repertoire and confers immunity against MOPC 315 myeloma tumors. In order to characterize the idiotopes on MOPC 315 IgA which elicit this response we have isolated four monoclonal antiidiotypic antibodies (AIA), D10 (IgG2a), A2(IgG1), G3 (IgG2b) and F1 (IgG2a), produced by splenocytes of BALB/c mice immunized with MOPC 315 IgA in three independent fusion experiments. These AIA react with MOPC 315 IgA. reassociated H315 L315 and F315V but not with free H315, L315, V315H or V3152. In addition the AIA do not react with the closely related DNP-binding IgA myeloma protein, MOPC 460, suggesting that they are directed against private idiotopes on MOPC 315 IgA. These idiotopes can be divided into two groups. Group I, defined by D10, A2 and G3 consists of two overlapping idiotopes, one of which is related to the hapten-binding site. The two idiotopes are formed by an interaction of amino acids in H315 and L315. Group II defined by F1 consists of one idiotope which is related to the hapten-binding site. This idiotope is comprised of an aminoacid sequence on H315 which requires an interaction with either L315 or L460 for expression. A2 and G3 react identically with the same idiotope but were derived from two independent fusion experiments. This indicates an identity of AIA clonotypes among individual mice and suggests that the isologous AIA response to MOPC 315 IgA is restricted.  相似文献   
10.
Two-hundred and four fine-needle aspiration biopsies of the pancreas have been performed in 190 patients during a 12-year period. Sixty-one of these were performed percutaneously guided by endoscopic retrograde cholangio-pancreatography, percutaneous transhepatic cholangiography, angiography, or ultrasonography; and 143 were taken intraoperatively. In 77 (67%) out of 115 patients with pancreatic cancer, a correct cytological diagnosis was obtained. Two biopsies were reported as malignant in 1 patient who ultimately was found to have chronic pancreatitis (false positives). The frequency of not representative biopsies varied from 20.8% in patients with suspected cancer biopsied intraoperatively to 48.4% in patients biopsied preoperatively. A correct cytological diagnosis of malignancy was obtained preoperatively in 54.6% of patients with cancer, in 60.0% of patients evaluated without later operation, and in 71.1% of patients biopsied during laparotomy for suspected pancreatic cancer. The overall false-negative rate was 9.8%. The predictive value of a positive test was almost 100%, whereas the predictive value of a negative test was only 69.6% (total material). Analyses may indicate that a more aggressive approach with multiple punctures may lower the not representative biopsy rate and increase the diagnostic accuracy in patients with pancreatic cancer.
Resumen Doscientas y cuatro biopsias pancreáticas por aspiración con aguja fina han sido realizadas en 190 pacientes en un período de 12 años. Sesenta y una de éstas fueron realizadas por vía percutánea guiada por colangiopancreatografía endoscópica retrógrada, colangiografía percutánea transhepática, angiografía, o ultrasonografía, y 143 fueron intraoperatorias. En 77 (67%) de 115 pacientes con cáncer del páncreas se obtuvo un diagnóstico citológico correcto. Dos biopsias fueron informadas como malignas en un paciente en quien finalmente se demostró pancreatitis crónica (falsas positivas). La frecuencia de biopsias no representativas varió entre 20.8% en pacientes con sospecha de cáncer y biopsia realizada intraoperatoriamente, a 48.4% en pacientes con biopsias realizadas en la fase preoperatoria. El diagnóstico citológico correcto de malignidad fue logrado preoperatoriamente en 54.6% de los pacientes con cáncer, en el 60.0% de los pacientes evaluados y sin operación posterior y en el 71.1% de los pacientes en quienes se realizó biopsia durante la laparotomía por sospecha de cáncer pancreático. La tasa global de resultados falsos negativos fue de 9.8%. El valor de predicción de una prueba positiva fue de casi 100%, mientras el valor de predicción de una prueba negativa fue de sólo 69.6% (material total). La implicación práctica de esto es que cuando se obtenga un resultado negativo se debe proceder con la toma de nuevas biopsias. En conclusión, creemos que la biopsia del páncreas con aguja fina es un procedimiento seguro que puede ser recomendado en todas las fases del proceso diagnóstico o terapéutico de lesiones pancreáticas, y que es valioso en la planeación de la terapia en pacientes con cáncer. Sinembargo, las biopsias negativas en casos de sospecha clínica de cáncer no siempre excluyen su presencia. Mayor análisis puede indicar que una actitud más agresiva, con punciones mÚltiples, puede disminuir la tasa de biopsias no representativas y aumentar la precisión diagnóstica en pacientes con cáncer pancreático.

Résumé Deux cent quatre biopsies-aspirations à l'aiguille fine du pancréas ont été pratiquées chez 190 sujets au cours d'une période de 12 ans. Soixante et une d'entre elles ont été pratiquées par voie souscutanée en étant guidées par cathétérisme rétrograde, cholangiographie transpariétale, angiographie ou ultrasonographie et 143 ont été effectuées au cours de l'intervention. Chez 77 (67%) sujets appartenant à une série de 115 malades atteints de cancer du pancréas le diagnostic cytologique exact a été porté. Deux biopsies en faveur du diagnostic de cancer répondaient en réalité à des lésions de pancréatite chronique (faux positifs). La fréquence des biopsies ininterprétables chez les sujets suspects de cancer a varié de 20.8% lorsque l'examen a été pratiqué au cours de l'intervention à 48.4% lorsque ce mÊme examen a été effectué avant l'opération. Le taux de diagnostic cytologique exact de cancer a été respectivement de 54.6%, de 60.0% et 71.1% selon que la biopsie cytologique a l'aiguille a été pratiquée avant l'intervention, après un certain délai et au cours de l'opération. Au total, le taux des faux positifs s'est élevé à 9.8%. La fiabilité de la biopsie à l'aiguille a été proche de 100% en cas de biopsie positive mais seulement de 69.6% en cas de biopsie négative. L'analyse de l'ensemble de ces faits incite à adopter une attitude plus agressive c'est-à-dire à pratiquer des biopsies multiples au lieu d'une ponction unique pour réduire le taux des prélèvements ininterprétables et accroÎtre celui des résultats exacts.
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