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61.
Nicotine intake, menstrual and smoking withdrawal symptomatology, and baseline cortisol and MHPG were assessed in nine women smokers under conditions of ad lib smoking and overnight abstinence in three menstrual phases (early follicular, mid-to-late follicular, and late luteal). A trend towards higher nicotine intake p <0.100 was observed in the mid-to-late follicular phase. Although me menstrual symptomatology was not significantly elevated during the smoking abstinence condition overall, abstinence appeared to prevent the normal reduction in symptomatology during the mid-to-late follicular phase that occurred under conditions of ad lib smoking. Menstrual and withdrawal symptoms were highly correlated, and both were most pronounced during the late luteal/abstinence condition. The smoking-specific item “craving” reflected this pattern, though in attenuated form, suggesting that the observed exacerbation of withdrawal symptomatology was not simply due to generalized dysphoria, as queried in both instruments. MHPG was significantly elevated in the late luteal phase, whereas cortisol was significantly higher during ad lib smoking than during abstinence and tended to be highest in the mid-to-late follicular phase. Further investigation will be needed to determine the functional significance of these findings for understanding and treating smoking in women.  相似文献   
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Genetic analysis of a set of six Mycobacterium tuberculosis strains differing in virulence for the guinea pig revealed an altered restriction enzyme fragmentation pattern associated with the superoxide dismutase (SOD) gene in a low-virulence, isoniazid-resistant strain. In addition, it was found that the SOD enzyme produced by the isoniazid-resistant strain differed in its electrophoretic mobility from the SOD of other M. tuberculosis strains. Detailed analysis of these strain-specific differences showed that the restriction fragment length polymorphism resulted from the presence of a copy of a repetitive element 552 bp upstream of the SOD gene and that the anomalous electrophoretic mobility arose from a single nucleotide change, resulting in replacement of an aspartic acid residue by histidine in the SOD enzyme of the isoniazid-resistant strain. Possible relationships between genetic changes and strain-dependent differences in virulence are discussed.  相似文献   
63.
BACKGROUND: Although it has been reported that ghost cells are present in odontomas, the generation mechanism of these cells is unclear. To evaluate the presence of ghost cells and involvement of the Wnt signaling pathway, we examined the expression of hard keratins, beta-catenin and Lef-1 in odontomas. METHODS: Sixty-nine cases of odontoma were examined immunohistochemically with the use of antibodies against human hair proteins, beta-catenin and Lef-1. RESULTS: Expression of hard keratins was found only in the cytoplasm of ghost cells in 46 (66.7%) of the 69 odontomas. Compound odontomas (78.8%) showed a higher incidence of ghost cells than complex odontomas (29.4%). Histopathologically, ghost cells were found within odontogenic epithelium adjacent to immature enamel and in the centre of Liesegang-ring-like calcified materials. Expression of beta-catenin and Lef-1 was observed in the cytoplasm and nucleus of odontogenic epithelial cells adjacent to the ghost cells in immature odontomas. CONCLUSION: These findings suggest that odontoma is a hard keratin-expressing tumor-like lesion, and that the Wnt signaling pathway may be involved in the formation of ghost cells in odontomas.  相似文献   
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The DRB1* polymorphism in 941 randomly selected individuals from the Umbilical Cord Blood Bank of Barcelona (92.75% of Spanish origin) was determined by sequence-based typing. The HLA profile was similar to that of other Mediterranean populations, with DRB1*0701 and *0301 being the most frequent alleles. This may be a consequence of the mixture of alleles as a result of migration from contiguous geographical areas.  相似文献   
67.
The standard of care for patients with cholestasis (direct bilirubin >or=2 mg/dL) while receiving parenteral nutrition (PN) solutions is to reduce or discontinue the copper and manganese. The repercussions of this action have not been studied. Two adult case reports document low serum copper levels associated with clinical symptoms of copper deficiency after the removal of copper from their PN solutions. We now describe the first known series of pediatric patients to develop copper deficiency after copper was removed from their PN solutions.  相似文献   
68.
BACKGROUND: The need to improve influenza vaccination delivery in our community became painfully clear during the winter of 1997-1998 when high rates of respiratory illness led to congestion in the emergency department and a critical shortage of hospital beds. In response, the local hospital and the Department of Health launched a collaborative program to increase influenza vaccine coverage in the community. METHODS: The partnership was designed to increase the number of citizens receiving influenza vaccine and to moderate the severity of lower respiratory tract illness during the winter season. A variety of methods were used to increase public awareness, enhance vaccine delivery, and create a relatively seamless service for the community. RESULTS: During three seasons, influenza vaccination rates increased by a relative 150%. This represented immunization of 16% of the entire community and more than 75% of residents older than 65 years. Hospital employee vaccination rates also rose from 34% to 58%. When compared with other hospitals in the county, the campaign reduced the average number of annual visits to the emergency department for all respiratory diagnoses by 34% and exacerbations of chronic obstructive pulmonary disease by 46%. CONCLUSIONS: This influenza vaccination program illustrates the potential for synergy that exists between local departments of health and community hospitals in successfully increasing vaccine delivery to the community. Furthermore, it also suggests that such efforts can be successful in reducing use of the emergency department, resulting in a positive impact on the health of the community.  相似文献   
69.
The exact opioid-sensitive receptors participating in EtOH-seeking behaviors remains unclear. Previous studies have reported higher densities of micro-opioid receptor binding in the nucleus accumbens (NACC) of P relative to NP rats; however, no differences were seen in delta-receptor binding. In contrast to the NACC, substantially lower levels of micro-receptor binding have been observed in the ventral tegmental area (VTA) of both P and NP rats, albeit no line differences have been observed. In the present study, opioid receptors in the NACC, VTA, and hippocampus were evaluated for their capacity to regulate both EtOH- and saccharin-motivated behaviors in the genetically selected alcohol-preferring (P) rat. To accomplish this, nalmefene, an opiate antagonist with preferential binding affinity for the micro-opioid receptor was unilaterally or bilaterally infused during concurrent availability of 1 h daily EtOH (10% v/v) and saccharin (0.025 or 0.050% w/v) solutions. Rats performed under a two-lever fixed ratio (FR) schedule in which four responses on one lever produced the EtOH solution, and four on a second lever produced the saccharin solution. The results demonstrated that when responding maintained by both EtOH and saccharin are matched at basal levels, unilateral (1-60 microg) or bilateral (0.5-10 microg) microinjections of nalmefene into the NACC produced selective dose-dependent reductions on responding maintained by EtOH. Unilateral (40, 60 microg) and bilateral (10 microg) VTA infusions were also observed to selectively reduced EtOH responding; however, greater nalmefene doses were required and the magnitude of suppression on EtOH responding was markedly less compared with the NACC. The greater sensitivity of nalmefene to suppress EtOH responding in the NACC is likely due to the greater number of opioid receptors in the NACC relative to the VTA. Only bilateral infusion of the 40 microg dose in the NACC and VTA suppressed responding maintained by both EtOH and saccharin. In contrast, intrahippocampal infusions dose dependently suppressed EtOH- and saccharin-maintained responding over a range of doses (1-20 microg). The present study provides evidence that nalmefene suppresses EtOH-motivated behaviors via blockade of opioid receptors within the NACC and VTA, and under various dose conditions both reinforcer and neuroanatomical specificity can be observed.  相似文献   
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