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1.
2.
To assess the augmented delta quotient (ADQ) monitor as a monitorof cerebral function during cardiac surgery, we monitored duringoperation the electroencephalograms of 48 young subjects (aged2 weeks to 19 yr). We found ADQ patterns produced by cardiopulmonarybypass, hypothermia and general anaesthetic agents correlatedwith those obtained from a compressed spectral array (CSA) monitorand could be differentiated from changes caused by cerebralischaemia, except in the youngest group of patients ( 18 months)undergoing deep hypothermia (19.4 (SD 0.8) °C nasopharyngeal).In all other age groups the ADQ proved to be a simple monitorof the adequacy of cerebral perfusion. Neurological deficitoccurred only if the ADQ was abnormal during hypotension fora period exceeding 7 min. ADQ evaluation of cerebral functionwas limited by events which produced artificially normal ADQreadings such as low amplitude EEG activity and the describedisoflurane effect that was demonstrated to occur in some cardiacpatients. The results obtained by the ADQ were comparable tothose obtained by compressed spectral array and the ADQ waseasier to use and interpret. *Present address: Department of Anaesthesia and Intensive Care,Basingstoke District Hospital, Basingstoke, Hants.  相似文献   
3.
A Two-Generation Reproduction Study in Rats Receiving DietsContaining Hexamethylenediamine. SHORT, R. D., JOHANNSEN, F.R., AND SCHARDEIN, J. L. (1991). Fundam. Appl. Toxicol. 16,490–494. Rats received diets containing average dailydoses of 0, 50, 150, and 500 mg/kg/ day of hexamethylenediamineover two generations. Although no treatment-related mortalitywas observed in any of the groups, the weight gain of adultsand pups was slightly reduced in the high dose group. Whilethe litter size was also slightly reduced at birth in the highdose group, there was no adverse effect on survival during lactationin any of the treated groups. Thus, the dietary administrationof up to 150 mg/kg/day of hexamethylenediamine over two generationsdid not adversely affect reproduction or fertility in rats.  相似文献   
4.
A new variant of congenital hemolyticanemia associated with stomatocytosis,reticulocytosis, decreased osmotic fragility, type I autohemolysis and shortened erythrocyte survival without specific splenic sequestration was discoveredin three siblings of Swiss-German ancestry. Increased intracellular sodium(two to three times normal) and slightlydecreased intracellular potassium weredetected. Total sodium efflux was eight-fold greater than normal but total potassium influx was normal and ouabain-sensitive potassium influx was decreased.The ouabain-sensitive sodium efflux:potassium influx ratio was 26:1 ratherthan the 3:2 ratio noted in normal cells.The consanguineous parents, four othersiblings, and 44 other family membershad mild stomatocytosis, reticulocytosis,and, when studied, decreased osmoticfragility, increased autohemolysis, intermediate abnormalities of cation content,cation flux, and moderate shortening oferythrocyte survival. Autosomal dominant inheritance was suggested. Noabnormalities of RBC enzymes, hemoglobin or lipids were observed. No abnormalities of membrane protein weredetected on acrylamide gel. Substratedepletion of these hypermetabolic cellsresulted in intracellular dehydrationwith potassium loss in excess of sodiumgain and decreased deformability. Although the exact nature of the defectresponsible for hemolysis is unknown,this syndrome differs from other hereditary hemolytic anemias associated withstomatocytosis.

Submitted on December 21, 1970 Revised on March 16, 1971 Accepted on March 29, 1971  相似文献   
5.
Stem Cell Migration and Proliferation During Severe Anemia   总被引:3,自引:2,他引:3  
The pluripotential stem cell (CFU) compartment of marrow and spleen wasevaluated in mice subjected to an intense erythroid stimulus associated withphenylhydrazine-induced anemia. Erythroid hyperplasia occurred in both marrow and spleen. CFU in the marrowgradually declined to approximately 50per cent of control levels (day 5) whiletheir numbers in the spleen increased(fourfold) by day 3 and were maintainedat this level for several days. Thesechanges in numbers of marrow andsplenic CFU were not associated withCFU proliferation. Thereafter, CFU inthe marrow, but not in the spleen, entered active cell cycle. The data suggestthat CFU migrate from marrow to spleenduring the demands of severe anemia.The induction of marrow CFU into cyclefurther suggests a negative feedback,which, perhaps through cell-cell interaction, maintains stem cells at a criticalcompartment size. The failure of splenicCFU to cycle may reflect the converseeffect, i.e. an inhibition on stem cell proliferation in the wake of an expandedstem cell pool.

Submitted on March 17, 1970 Revised on May 14, 1970 Accepted on June 9, 1970  相似文献   
6.
This study evaluates the effect of adjuvant immunotherapy with BCG alone, or combined with melanoma cell vaccine, on the recurrence and survival rates of patients with metastatic melanoma in the regional lymph nodes who were treated by lymphadenectomy. Patients were prospectively randomized and stratified on the basis of age, sex, site of primary tumour, and clinical estimate of the regional nodes. During the past four years, 134 patients were entered into this trial, and to date, the incidence of recurrence among the two arms mentioned and the control arm is not significantly different; however, patients receiving BCG alone had longer survival than those in either the tumour cell vaccine or control groups. The improved survival in the BCG-only group was found to be due to the fact that patients survived longer with their recurrent disease than the patients in the other two groups. At the present time, these differences do not appear to be significant enough to justify routine adjuvant immunotherapy in patients with melanoma metastatic to regional nodes. Longer follow-up will be necessary to evaluate the role of adjuvant immunotherapy of Stage II melanoma.  相似文献   
7.
8.
Smoking patterns at a British and at an American medical school   总被引:1,自引:0,他引:1  
Cigarette smoking among medical students at the University of Bristol (Bristol) and the New York University School of Medicine (NYU) was investigated and differences were subjected to statistical analysis.
At Bristol 34–6% and at NYU 14–3% of respondents classified themselves as regular smokers. Among students in the pre-clinical phase of training the difference between the number of smokers at Bristol and at NYU was not significant. At both schools more clinical students smoked than preclinical students, but only at Bristol did the difference between the number of smokers in the two grade levels reach statistical significance.
There are fewer heavy smokers (consumers of more than twenty cigarettes per day) among the pre-clinical students at Bristol than among preclinicals at NYU. In the clinical year, however, there were slightly (insignificantly) fewer heavy smokers at NYU while there were significantly more at Bristol.
Smokers at NYU acquired the habit at a somewhat earlier age than the smokers at Bristol.
The majority of students at both schools indicated that medical education had not influenced their decision to smoke or not to smoke.
Most smokers—more among the clinical than the pre-clinical students—reported that they were displeased with their habit and that they wished to give it up. Somewhat fewer smokers at Bristol gave that response than students at NYU.
Factors contributing, at least in part, to the differences between smoking patterns observed may be variables of age and years of education.
The widely held but untested belief that precept and example by medical school teachers may be a potent force for modifying the smoking behaviour of health professionals, is in need of research.  相似文献   
9.
Rat platelets were labeled with tritiated diisopropylfluorophosphate(3H-DFP) during recovery from acute thrombocytopenia. The results indicated that there was significant labeling of megakaryocytes by 3H-DFPwhich, in the presence of an increased rate of platelet production, resulted inmaintenance of relatively constant values for platelet-bound radioactivity during the period of maximum platelet production and reactive thrombocytosis.Significant random loss of platelets was apparent, and, when a cohort ofyoung platelets was transfused to normal recipients, they were destroyed at anormal rate.

  相似文献   
10.
Summary. Pregnancy-associated plasma protein-A (PAPP-A) and Schwangerschaftsprotein 1 (SP1) levels were measured in single serum samples from 60 patients admitted with vaginal bleeding in the first 14 weeks of pregnancy. When based on ultrasound diagnoses the prediction of non-viability (the predictive value) was 97% for SP1 and 84% for PAPP-A. Whereas the prediction of viability (above –2SD of the normal range) with SP1 was 88% the value with PAPP-A was only 57%; the poorer result obtained with PAPP-A probably reflects its longer half-life. Pregnancy outcome is not related to the duration of bleeding.  相似文献   
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