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31.
A severe case of aplasia cutis congenita in a preterm infant is described. Although major problems with thermoregulation and fluid balance were anticipated, these parameters were relatively easy to control once the patient was stabilized. Meticulous skin care and rapid formation of a membranous-like fibrous tissue layer covering the denuded areas probably played an important role in minimizing excessive fluid and heat loss. The prognosis in aplasia cutis congenita is determined by the underlying associated anomalies, the severity of skin lesions and, in our case, the maturity of the infant who died from complications of prematurity.  相似文献   
32.
This is the first controlled prospective study of the effects of nicotine deprivation in adolescent smokers. Heart rate and subjective withdrawal symptoms were measured over an 8-hr period while participants smoked normally. Seven days later, participants were randomized to wear a 15-mg (16-hr) nicotine patch or a placebo patch for 8 hr, and they refrained from smoking during the session. Those wearing the placebo experienced a decrease in heart rate across sessions and an increase in subjective measures of nicotine withdrawal. Those wearing the active patch also reported significant increases for some subjective symptoms. Expectancy effects were also observed. The findings indicate that adolescent smokers experience subjective and objective changes when deprived of nicotine. As in previous research with adults, expectancies concerning the effects of nicotine replacement also influenced perceptions of withdrawal.  相似文献   
33.
Two-component regulatory proteins, histidine kinases and response regulators, function in bacteria as sensing and adaptive factors in response to a wide range of environmental stimuli. Conserved histidine and glycine regions of histidine kinase sensor proteins were used to design degenerate oligonucleotide primers for amplification of DNA fragments from Mycobacterium tuberculosis. Two adjacent genes, trcR and trcS, which encode a response regulator and a histidine kinase, respectively, have been identified. Full-length and truncated TrcR and TrcS proteins have been expressed in Escherichia coli. Difficulties in expressing recombinant full-length TrcS and a truncated N -terminal form of TrcS reveal that the transmembrane domains are toxic to E. coli. Overexpressed truncated C-terminal transmitter domains of TrcS have been autophosphorylated in vitro and have transphosphorylated both the full-length recombinant TrcR protein and the N -terminal receiver/regulator domain of TrcR. In vitro autophosphorylation of TrcS requires the presence of Mn2+or Ca2+as a divalent cation cofactor and subsequent transphosphorylation of TrcR is evident in the presence of TrcS-phosphate and Ca2+. Transphosphorylation between these two proteins provides evidence that these M. tuberculosis genes encode functional two-component system regulatory proteins that are members of a signal transduction circuit.  相似文献   
34.
We present data from an exploratory study of 174 adults with Marfan syndrome regarding their cognitive perceptions of the condition as postulated by the self-regulatory model (Leventhal H, Benyamini Y, Brownlee S et al. In: Petrie KI, Weinman JA, eds. Perceptions of Health and Illness: Current Research and Applications. Amsterdam, The Netherlands: Harwood Academic, 1997: 19-45; Leventhal H, Nerenz DR, Steele DJ. In: Baum A, Taylor SE, Singer JE, eds. Handbook of Psychology and Health. Hillsdale, NJ: Lawrence Erlbaum Associates, 1984: 219-252). The vast majority of the respondents had adequate general knowledge about Marfan syndrome. Eighty-three percent of the respondents perceived Marfan syndrome as having had significant adverse consequences on their lives. Having striae, pain (sore joints), and depression were each independently correlated with this view. Fifty-eight percent of the respondents indicated that they felt they had low to moderate control over their condition, demonstrating variability. History of aortic dissection, pain (sore joints), and depressive symptoms were each negatively correlated with the view that Marfan syndrome is a curable/controllable condition. Moreover, approximately 28% view the condition as a lethal condition, whereas 67% view it as a serious condition. Forty-four percent of the cohort were found to have significant symptomatology of depression independent of beta- and Ca2+-channel blockade use. Respondents cited both advantages and disadvantages of being affected. Genetic counseling that addresses patients' perceptions of Marfan syndrome, and its associated pain, fatigue, and depressive symptoms, may enhance patient adaptation to the condition.  相似文献   
35.
Objective  To test the hypothesis that iron supplement from early pregnancy would increase the risk of gestational diabetes mellitus (GDM).
Design  Randomised placebo-controlled trial.
Setting  A university teaching hospital in Hong Kong.
Population  One thousand one hundred sixty-four women with singleton pregnancy at less than 16 weeks of gestation with haemoglobin (Hb) level between 8 and 14 g/dl and no pre-existing diabetes or haemoglobinopathies.
Methods  Women were randomly allocated to receive 60 mg of iron supplement daily ( n = 565) or placebo ( n = 599). Oral glucose tolerance tests (OGTTs) were performed at 28 and 36 weeks. Women were followed up until delivery.
Outcome measures  The primary outcome was development of GDM at 28 weeks. The secondary outcomes were 2-hour post-OGTT glucose levels, development of GDM at 36 weeks and delivery and infant outcomes.
Results  There was no significant difference in the incidence of GDM in the iron supplement and placebo groups at 28 weeks (OR: 1.04, 95% confidence interval [CI]: 0.7–1.53 at 90% power) or 36 weeks. Maternal Hb and ferritin levels were higher in the iron supplement group at delivery ( P < 0.001 and P = 0.003, respectively). Elective caesarean section rate was lower in the iron supplement group (OR: 0.58, 95% CI: 0.37–0.89). Infant birthweight was heavier ( P = 0.001), and there were fewer small-for-gestational-age babies in the iron supplement group (OR: 0.46, 95% CI: 0.24–0.85).
Conclusion  Iron supplement from early pregnancy does not increase the risk of GDM. It may have benefits in terms of pregnancy outcomes.  相似文献   
36.
Interpeduncular fossa sign: CT criterion of subarachnoid hemorrhage   总被引:1,自引:0,他引:1  
Yeakley  JW; Patchall  LL; Lee  KF 《Radiology》1986,158(3):699-700
A retrospective study of 100 cerebral computed tomography scans interpreted as displaying subarachnoid hemorrhage was undertaken to determine the frequency of blood in the interpeduncular fossa as a useful radiographic sign. The results indicate that the interpeduncular fossa sign is second only to blood in the Sylvian fissure-circular sulcus area as a reliable indicator of subarachnoid hemorrhage on CT scans.  相似文献   
37.
38.
We reviewed the clinical course of 32 children with cancer who received nutrition through a feeding tube placed percutaneously during gastroscopy (PEG). Their median age was 5.1 y (75%, range: 1.8-13.7 y, min: 3.5 mo) when the PEG was done 0.7-23 mo after diagnosis (median: 1.8 mo, 75%; range: 0.9-8 mo). Five of the children underwent bone marrow transplantation with the gastrostomy in place. There was a significant (p  相似文献   
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40.

Background  

Streptobacillus moniliformis is a zoonotic agent associated with rodent contacts. Although it is more commonly reported to cause rat-bite fever with reactive arthritides, it can also lead to pyogenic infection of the joints.  相似文献   
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