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1.
On the Orientation of the HL-A Region and the PGM3 Locus in the Chromosome   总被引:1,自引:0,他引:1  
A study of four families with a cross-over within the HL—A region and in which the crossover parent is heterozygous at PGM3 indicates with a probability of about 95% that the chromosomal orientation of the three linked loci is LA · FOUR · PGM3.  相似文献   
2.
The effects of tricresyl phosphate (TCP) and butylated triphenylphosphate (BTP)-based hydraulic fluid on reproduction were studiedin F344 rats using a modification of the National ToxicologyProgram's Continuous Breeding Protocol. Groups of breeding pairsreceived single daily oral doses of an equal volume of either0, 0.6, 1.0 g BTP/kg or 0.4 g TCP/kg in sesame oil or 1.7 gneat BTP/kg for up to 135 days. A naive control group allowedto breed, but not dosed or handled daily, demonstrated thatdaily dosing and handling of the rats had no effect on reproduction.The fertility index and number of litters born were significantlydecreased in rats exposed to 1.0 and 1.7 g BTP/kg and 0.4 gTCP/kg. The number of pups per litter was significantly decreasedin the TCP group. A crossover mating experiment using 0.4 gTCP/kg/day and 1.0 g BTP/kg/day groups, each mated with vehiclecontrols, demonstrated that TCP caused 100% infertility in malerats but did not affect reproduction in females. BTP causeda significant decline in reproduction in female rats characterizedby low mating and fertility indices, decreased number of litters,and abnormal estrous cycles. Fertility was decreased in theBTP-dosed male rats. Both sexes of rats in the crossover experimentwith TCP and BTP had significant decreases in terminal bodyweights and increases in adrenal gland and liver weights. OnlyTCP-dosed male rats had significantly decreased testicular andepididymal weights. TCP-dosed female rats had increased ovarianweights, while BTP-dosed females had significantly lower uterineweights. The results of this study indicate that BTP and TCPare reproductive toxicants in F344 rats.  相似文献   
3.
Adenosine and Retrograde Fast Pathway Conduction . Introduction : Several studies have shown that the fast pathway is more responsive to adenosine than the slow pathway in patients with AV nodal reentrant tachycardia. Little information is available regarding the effect of adenosine on anterograde and retrograde fast pathway conduction.
Methods and Results : The effects of adenosine on anterograde and retrograde fast pathway conduction were evaluated in 116 patients (mean age 47 ± 16 years) with typical AV nodal reentrant tachycardia. Each patient received 12 mg of adenosine during ventricular pacing at a cycle length 20 msec longer than the fast pathway VA block cycle length and during sinus rhythm or atrial pacing at 20 msec longer than the fast pathway AV block cycle length. Anterograde block occurred in 98% of patients compared with retrograde fast pathway block in 62% of patients ( P < 0.001). Unresponsiveness of the retrograde fast pathway to adenosine was associated with a shorter AV block cycle length (374 ± 78 vs 333 ± 74 msec, P < 0.01), a shorter VA block cycle length (383 ± 121 vs 307 ± 49 msec, P < 0.001), and a shorter VA interval during tachycardia (53 ± 23 vs 41 ± 17 msec, P < 0.01).
Conclusion : Although anterograde fast pathway conduction is almost always blocked by 12 mg of adenosine, retrograde fast pathway conduction is not blocked by adenosine in 38% of patients with typical AV nodal reentrant tachycardia. This indicates that the anterograde and retrograde fast pathways may be anatomically and/or functionally distinct. Unresponsiveness of VA conduction to adenosine is not a reliable indicator of an accessory pathway.  相似文献   
4.
During recent years, percutaneous transhepatic catheterization of the portal venous system has become the most accurate procedure for investigation of the portal system. The procedure can be performed under local analgesia, is relatively simple, and complications are rare. The success rate is high, approximately 90%, especially when the liver hilum is localized by ultrasonography prior to catheterization. The free portal pressure can be measured. Selective catheterization of all portal tributaries can be performed. The indications are: portography in patients with cirrhosis of the liver and portal hypertension for delineation of collateral vein systems including gastro-oesophageal varices; visualization of veins that may be used for portosystemic shunt operations; postoperative control of shunt patency; diagnosis of portal and hepatic vein thrombosis; localization of stenosis in the portal vein system; pre-operative evaluation of patients with tumours in the biliary tract and pancreas; obliteration of bleeding oesophageal varices; and verification and localization of endocrine pancreatic tumours making curative resection possible. Further, transhepatic catheterization of the portal system may be used in research on the development of portal hypertension, collateral veins, variceal bleeding, and for haemodynamic, metabolic and pharmacologic studies in the gastrointestinal tract.  相似文献   
5.
Nationwide, CTX‐M‐producing clinical Escherichia coli isolates from the Norwegian ESBL study in 2003 (n=45) were characterized on strain and plasmid levels. BlaCTX‐M allele typing, characterization of the genetic environment, phylogenetic groups, pulsed field gel electrophoresis (PFGE), serotyping and multilocus sequence typing were performed. Plasmid analysis included S1‐nuclease‐PFGE, polymerase chain reaction‐based replicon typing, plasmid transfer and multidrug resistance profiling. BlaCTX‐M‐15 (n=23; 51%) and blaCTX‐M‐14 (n=11; 24%) were the major alleles of which 18 (78%) and 6 (55%), respectively, were linked to ISEcp1. Thirty‐two isolates were of phylogenetic groups B2 and D. Isolates were of 29 different XbaI‐PFGE‐types including six regional clusters. Twenty‐three different O:H serotypes were found, dominated by O25:H4 (n=9, 20%) and O102:H6 (n=9, 20%). Nineteen different STs were identified, where ST131 (n=9, 20%) and ST964 (n=7, 16%) were dominant. BlaCTX‐M was found on ≥100 kb plasmids (39/45) of 10 different replicons dominated by IncFII (n=39, 87%), FIB (n=20, 44%) and FIA (n=19, 42%). Thirty‐nine isolates (87%) displayed co‐resistance to other classes of antibiotics. A transferable CTX‐M phenotype was observed in 9/14 isolates. This study reveals that the majority of CTX‐M‐15‐expressing strains in Norway are part of the global spread of multidrug‐resistant ST131 and ST‐complex 405, associated with ISEcp1 on transferrable IncFII plasmids.  相似文献   
6.
Arteriovenous pulmonary fistulas present in infancy in more than half the number of cases. A distinction is drawn between isolated and multiple fistulas, and as a special category of the latter, the disperse telangiectatic type, is described. A review of the literature reveals 17 cases of this type. The present case extends this series—a girl dying at the age of 6 months, in whom the diagnosis of disperse telangiectatic arteriovenous pulmonary fistulas was regarded as probable on the basis of the investigations made. The diagnosis was confirmed at autopsy, which included bronchovascular injection of contrast during fluoroscopy. The relationship to the dominant hereditary Disease telangiectasia hereditaria (Rendu-Osler disease) is discussed. It is emphasized that this relationship appears particularly clear in the telangiectatic type, a circumstance which is however not confirmed in the present case. The difficulties in diagnosis and the diagnostic procedures are mentioned.  相似文献   
7.
ABSTRACT The effect of cimetidine (1 g daily) and placebo was studied in a controlled clinical trial comprising 50 patients with non-ulcer dyspepsia in whom an organic abnormality responsible for the dyspeptic symptoms was not disclosed by a standardized and extensive examination programme. Reduction of symptoms occurred in 13 (54%) out of 24 patients treated with cimetidine and in 16 (62%) out of 26 treated with placebo. The difference was insignificant, as were the alterations in the individual dyspeptic symptoms between the groups. Only 6 patients (25%) on cimetidine and 8 (31%) on placebo treatment had a total relief of symptoms. Of these, all cimetidine-treated patients remained free from symptoms during the successive 3-month observation period, while the dyspeptic symptoms relapsed in 3 (38%) placebo-treated patients. Subsequent resumption of placebo treatment reduced the symptoms in all 3 patients, but only one became free from symptoms. Cimetidine does not seem to be superior to placebo in the treatment of non-ulcer dyspepsia in patients without any previous history of ulcer or without any sign on endoscopy of an active or previous ulcer disease.  相似文献   
8.
A combined dye exclusion (Trypan Blue) and fluorochromatic technique for lymphocytotoxicity test is described. The technique allows the test to be read either as a dye exclusion or a fluorochromatic assay as required, and is found to be useful for typing lymphocyte samples with a high background of killed cells present. It is suggested that frozen lymphocytes, as well as samples which are shipped from one laboratory to another over a long distance and thus easily subjected to inadvertent damage during transit, should be labelled with Fluorescein Diacetate prior to their typing using the combined technique.  相似文献   
9.
Abstract — The present study was undertaken in order to evaluate whether electrodermal activity was a useful tool with which to measure dental anxiety in a group of drug addicts. Electrodermal activity was compared to the subjects' self-reported feelings during ordinary dental treatment sessions. In the first part of the study the level of electrodermal activity during treatment sessions was videotaped and recorded on paper by means of a polygraph. The patients were interviewed using a semi-structured questionnaire dealing with the addicts' dental anxiety and fear. In connection with the interviews the addicts completed Corah's Dental Anxiety Scale (CDAS). There was no recognizable pattern in electrodermal activity when this was compared with the patients' feelings during the treatments. Median CDAS was 9.5. In the second part of the study, electrodermal activity was recorded on the polygraph only. This group also completed a CDAS questionnaire. No correlation between the patients' self-reported highest level of anxiety and level of electrodermal activity, number of fluctuations or amplitude in relation to specific dental stimuli was found; agreement was found in two, three and none of 10 cases respectively. Median CDAS was 10.0. It could be concluded that, although the study revealed apprehension and situational anxiety among the addicts, no correlation to electrodermal activity was found. This discrepancy between the physiological and cognitive data probably reflects the uncertainty of these measures under the given circumstances.  相似文献   
10.
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