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21.
Feleppa Michele Di Iorio Walter Saracino Donato M. T. 《The journal of headache and pain》2004,5(2):s51-s58
We reviewed P300 and contingent negative variation (CNV) studies performed in migraine in order to identify their relevance in migraine and the role of neurophysiology in migraine. Publications available to us were completed by a Medline search. There is experimental and clinical evidence for loss of cognitive habituation in migraine which may serve as a specific diagnostic tool; therefore, we reviewed studies on migraine that analyzed habituation and lack of habituation by P300 and CNV, performing short-term habituation (STH) and long-term habituation (LTH). Finally, we described the two components of P300 (a and b) and of CNV (early and late wave) and the two abnormalities reported from the majority of studies on event-related potential in migraine: increased amplitude of average event-related potential and lack of habituation. These abnormalities are especially related to the early component characterizing orienting activity. 相似文献
22.
The prevalence of bad self-rated health (SRH) varies considerably across countries. Here we present the results of a cross-national comparative study based on the data of National Health Surveys conducted in France and Italy. According to these data, 11% of the Italian and 6% of the French adult population aged between 45 and 74 rate their health as bad or very bad. This gap may result from differences in population structure regarding the individual characteristics (sociodemographic characteristics, diseases and disabilities, lifestyle, and others) that impact on SRH i.e., a structural effect. It may also be that the link between these characteristics and SRH is “country-specific” i.e., a contextual effect. We use logistic regression models to assess the contribution of both explanations. We find that the structural effect plays a prominent role in the higher prevalence of bad SRH in Italy compared to France. 相似文献
23.
Giuseppina Di Stefano Luigi Fiume Michele Baglioni Corrado Busi Pasquale Chieco Felix Kratz Alessandro Mattioli 《European journal of pharmaceutical sciences》2007,30(2):136-142
Several attempts have been made to enhance doxorubicin (DOXO) concentrations in tumour cells by drug conjugation with human albumin (HSA). HSA-DOXO has the drawback of causing DOXO accumulation in spleen and bone marrow, with a consequent leucopoenia not produced when lactose molecules are coupled to the carrier protein. In the present experiments we demonstrated that the effect of HSA lactosamination is not a consequence of a more rapid disappearance from the bloodstream of the lactosaminated conjugate (L-HSA-DOXO), which is rapidly internalized by the liver through the asialoglycoprotein receptor, but is due to a hindered uptake by spleen and bone marrow cells caused by the coupled lactose molecules. Experiments in vitro showed that HSA-DOXO produced an inhibition of murine macrophage proliferation not caused by L-HSA-DOXO. This result can be explained by higher amounts of the former conjugate entering in these cells and suggests macrophages as the cell type responsible for the spleen and bone marrow internalization of HSA-DOXO hindered by lactose coupling. Importantly, lactosamination of HSA did not reduce the marked uptake of HSA-DOXO by chemically induced rat hepatocellular carcinoma. L-HSA-DOXO, by avoiding DOXO accumulation in bone marrow is an attractive candidate for clinical trials against tumors which were found to actively internalize this conjugate in laboratory animals, such as hepatocellular carcinoma. 相似文献
24.
Francesco Bertoni Giovanni Cazzaniga Giovanna Bosshard Enrico Roggero Renzo Barbazza Michele De Boni Carlo Capella Ennio Pedrinis Franco Cavalli rea Biondi & Emanuele Zucca 《British journal of haematology》1997,97(4):830-836
Gastric MALT lymphoma usually develops from chronic gastritis, the vast majority of which (>90%) is associated with Helicobacter pylori infection. We sequenced the third complementarity determining region (CDR3) of immunoglobulin heavy chain genes in 19 gastric MALT lymphoma clones to determine the pattern of variable (V), diversity (D) and joining (J) gene utilization during immunoglobulin gene rearrangement.
DNA was extracted from paraffin-embedded sections and the rearranged CDR3 regions were amplified using a semi-nested polymerase chain reaction (with primers complementary to the conserved framework-three segment of the variable region [FR3A] and J regions). The DNA used for cloning and sequencing was obtained after purification of monoclonal bands excised from polyacrylamide gels. The N-D-N region specific to each clone was compared with known germline D sequences.
Similarly to that observed in normal and leukaemic B cells, our series of gastric MALT lymphomas showed apparent preferential utilization of genes from the DXP family. In two cases no similarity between the CDR3 nucleotide sequences of the neoplastic clones and the known germline D sequences could be found. In 10/19 analysed alleles the lymphoma B-cell clones appeared to contain two D gene segments (D-D recombination), a rare occurrence in normal individuals but one which has been described as a significant event in the determination of idiotype expression and antigen-binding affinity. Remarkably, despite the use of different D and J segments, the resultant amino acid sequences matched in two patients, suggesting the presence of a common selecting antigen.
The observed pattern of D gene rearrangement suggests that MALT lymphoma B-cell clones have undergone antigen selection, which seems to indicate that the antigen stimulation plays a pivotal role in the development of the lymphoma. 相似文献
DNA was extracted from paraffin-embedded sections and the rearranged CDR3 regions were amplified using a semi-nested polymerase chain reaction (with primers complementary to the conserved framework-three segment of the variable region [FR3A] and J regions). The DNA used for cloning and sequencing was obtained after purification of monoclonal bands excised from polyacrylamide gels. The N-D-N region specific to each clone was compared with known germline D sequences.
Similarly to that observed in normal and leukaemic B cells, our series of gastric MALT lymphomas showed apparent preferential utilization of genes from the DXP family. In two cases no similarity between the CDR3 nucleotide sequences of the neoplastic clones and the known germline D sequences could be found. In 10/19 analysed alleles the lymphoma B-cell clones appeared to contain two D gene segments (D-D recombination), a rare occurrence in normal individuals but one which has been described as a significant event in the determination of idiotype expression and antigen-binding affinity. Remarkably, despite the use of different D and J segments, the resultant amino acid sequences matched in two patients, suggesting the presence of a common selecting antigen.
The observed pattern of D gene rearrangement suggests that MALT lymphoma B-cell clones have undergone antigen selection, which seems to indicate that the antigen stimulation plays a pivotal role in the development of the lymphoma. 相似文献
25.
Patrick M. Rao M.D. A. John Kuta M.D. Michele H. Johnson M.D. 《Emergency radiology》1995,2(5):303-304
We present a case in which an open fracture of the ulna penetrated the skull and caused a comminuted, depressed skull fracture
with a large intraparenchymal hematoma containing bone fragments. 相似文献
26.
27.
Phyllis W Sharps Ayman A E El-Mohandes M Nabil El-Khorazaty Michele Kiely Tessa Walker 《Journal of perinatology》2003,23(5):414-419
OBJECTIVE: To describe breastfeeding initiation among 210 urban African-American mothers with inadequate prenatal care. METHODS: This study is a case-control study of postpartum mothers recruited from four large urban hospitals. RESULTS: Mothers who chose to breastfeed were more educated, employed before birth, married, and using contraception postnatally. Regression model analysis controlling for demographic differences revealed that breastfeeding was significantly associated with a higher perception of severity of illness and higher confidence in the ability of health care to prevent illness. Breastfeeding mothers were less likely to reverse parent-child roles and had a lower perception of hassle from their infant's behavior. When comparing mothers who breastfed longer than 8 weeks to those who did not breastfeed, breastfeeding mothers had high scores related to empathy toward infants on the Adult-Adolescent Parenting Inventory as well as a low perception of hassle on the Parenting Daily Hassle. The perception of existing formal or informal social support did not influence breastfeeding behavior. CONCLUSION: Personal attributes of low-income urban mothers such as health beliefs and parental attitudes may play a role in the initiation and duration of breastfeeding. Low-income African-American mothers may be influenced in their choice to breastfeed by supportive messages from physicians and nurses delivering care to mothers and their newborns. Emphasis should be placed on the role breastfeeding can play in preventing childhood illnesses. 相似文献
28.
29.
Scott L Kominsky Michele Doucet Kelly Brady Kristy L Weber 《Journal of bone and mineral research》2007,22(1):37-44
Bone metastases develop in approximately 30% of patients with RCC, and the mechanisms responsible for this phenomenon are unknown. We found that TGF-beta1 stimulation of RCC bone metastasis cells promotes tumor growth and bone destruction possibly by stimulating paracrine interactions between tumor cells and the bone. INTRODUCTION: Bone metastasis is a frequent complication and causes marked morbidity in patients with renal cell carcinoma (RCC). Surprisingly, the specific mechanisms of RCC interaction with bone have been scarcely studied despite the inability to prevent or effectively treat bone metastasis. Bone is a reservoir for various growth factors including the pleiotropic cytokine TGF-beta1. TGF-beta1 has been shown to have tumor-supportive effects on advanced cancers and evidence suggests its involvement in promoting the development of breast cancer bone metastasis. Here, we studied the potential role of TGF-beta1 in the growth of RCC bone metastasis (RBM). MATERIALS AND METHODS: To inhibit TGF-beta1 signaling, RBM cells stably expressing a dominant-negative (DN) TGF-betaRII cDNA were generated. The in vivo effect of TGF-beta1 on RBM tumor growth and osteolysis was determined by histological and radiographic analysis, respectively, of athymic nude mice after intratibial injection of parental, empty vector, or DN RBM cells. The in vitro effect of TGF-beta1 on RBM cell growth was determined after TGF-beta1 treatment by MTT assay. RESULTS: TGF-beta1 and the TGF-beta receptors I and II (TGF-betaRI/II) were consistently expressed in both RBM tissues and cell lines. Inhibition of TGF-beta1 signaling in RBM cells significantly reduced tumor establishment and osteolysis observed in vivo after injection into the murine tibia, although no effect on tumor establishment was observed after injection of RBM cells subcutaneously or into the renal subcapsule. Treatment of five RBM cell lines with TGF-beta1 in vitro either had no effect (2/5) or resulted in a significant inhibition (3/5) of cell growth, suggesting that TGF-beta1 may promote RBM tumor growth indirectly in vivo. CONCLUSIONS: TGF-beta1 stimulation of RBM cells plays a role in promoting tumor growth and subsequent osteolysis in vivo, likely through the initiation of tumor-promoting paracrine interactions between tumor cells and the bone microenvironment. These data suggest that inhibition of TGF-beta1 signaling may be useful in the treatment of RBM. 相似文献
30.
Antonio Bobbio Alfredo Chetta Paolo Carbognani Eveline Internullo Alessia Verduri Giulianoezio Sansebastiano Michele Rusca Dario Olivieri 《European journal of cardio-thoracic surgery》2005,28(5):754-758
OBJECTIVE: Pulmonary Function Tests (PFT) and Cardio-Pulmonary Exercise Testing (C-PET) are useful to evaluate operability in functionally compromised patients. Although modifications of PFT and C-PET after lung surgery have been widely explored, little information exists as to modifications of exercise capacity in COPD patients undergoing lung resection. We prospectively analyzed the changes in PFT and C-PET in patients with COPD after a pulmonary lobar resection. METHODS: From January 2003 to March 2004 all patients scheduled for lung resection were considered for participation in the study protocol. Those patients with a preoperative diagnosis of COPD on PFT were explored through a C-PET. Only patients who had undergone a lobar pulmonary resection were subsequently considered; these patients had a new complete cardio-respiratory evaluation 3 months after surgery. The pre- and postoperative values compared were those of FEV1, TLC, DLCO, VO2max, and VE/VCO2. Data are expressed as mean +/- standard deviation (SD). Statistic evaluation was made using the Wilcoxon test. RESULTS: During this period 11 patients completed the study protocol. Ten patients underwent surgery for NSCLC and one for a pulmonary aspergilloma. Nine lobectomies and two bilobectomies were performed. In the study population, the preoperative mean value of FEV1 resulted as being 53% (SD+/-20) of the predicted mean value, that of TLC 120% (SD+/-35) and that of DLCO 65% (SD+/-27). The preoperative mean value of VO2max resulted as being 17.8 ml/Kg/min (SD+/-3.25) and mean VE/VCO2 resulted as being 35.7 (SD+/-4). Three months after surgery the measured mean value of FEV1 was 53% (SD+/-18), that of TLC was 99% (SD+/-24) and that of DLCO 52% (SD+/-18). The mean value of VO2max resulted as being 14.1 ml/Kg/min (SD+/-3.04) and that of VE/VCO2 was 42.5 (SD+/-12.8). Statistical analysis of PFT values showed that FEV1 and DLCO were not significantly modified (P > 0.05); in contrast, TLC had significantly decreased (P = 0.008). VO2max had significantly decreased (P = 0.004) and VE/VCO2 had significantly increased (P = 0.018). CONCLUSIONS: Three months after a lobar pulmonary resection, patients with COPD were found to have a significant decrease in exercise tolerance. PFT alone can underestimate the postoperative loss of exercise capacity through exercise. 相似文献