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排序方式: 共有1531条查询结果,搜索用时 31 毫秒
91.
Paola Roggero MD Arianna Bonfiglio MD Sergio Luzzani MD Alberto Valad MD Elena Cataliotti MD Giovanna Corno MD Maria Cristina Garlaschi MD Emanuela Carissimi MD Fabio Mosca MD Vittorio Carnelli MD 《The Journal of pediatrics》2002,140(6):775
We evaluated an antigen-based stool assay as an indicator of Helicobacter pylori (Hp) status during treatment aimed at eradicating Hp in 22 Hp-positive patients and 63 negative control patients. The sensitivity and specificity of the assay was 100% and 70%, respectively, when the manufacturer's cutoff was used. When we used the cutoff calculated from a receiver operating characteristic curve, the specificity of this test increased. Under these conditions, the test could be used in monitoring treatment and verifying eradication of Hp infection. Further studies must be carried out to standardize the cutoff in children. (J Pediatr 2002;140:775-7) 相似文献
92.
93.
The case of a patient who had recently undergone renal transplantation, and showed symptoms referable to pulmonary infection, is discussed. Chest X-ray showed the presence of bilateral diffuse reticulonodular interstitial involvement. For better characterization HRCT was performed. It detected ground glass interstitial involvement associated with nodules predominant in posterior segments of bilateral lower lobes. The case history associated with the findings of diagnostic imaging are strongly suggestive for pulmonary infection. The diagnosis was confirmed by bronchoalveolar lavage positive for the presence of alveolar cells and intranuclear and intracytoplasmic inclusions typical of Cytomegalovirus infection. 相似文献
94.
Ferretti V Florian C Costantini VJ Roullet P Rinaldi A De Leonibus E Oliverio A Mele A 《Psychopharmacology》2005,179(1):108-116
Rationale The nucleus accumbens receives glutamatergic and dopaminergic inputs converging onto common dendrites. Recent behavioral data demonstrated that intra-accumbens administrations of either glutamate or dopamine (DA) antagonist impair spatial memory consolidation. Thus, also based on the biochemical and molecular findings demonstrating interactions among the different receptors subtypes for glutamate and dopamine, it is conceivable that memory consolidation within this structure might be modulated by glutamate–dopamine receptor interactions.Objectives The purpose of this study was to examine the effects of intra-accumbens co-administrations of glutamate and DA antagonists on the consolidation of spatial information.Methods On day 1, CD1 male mice were placed in an open field containing five different objects and immediately after three sessions of habituation the animals were injected intra-accumbens with either vehicle or low doses of the N-methyl-d-aspartate (NMDA; AP-5 50 ng/side), the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA; DNQX 5 ng/side), the D1 (SCH23390 12.5 ng/side) and the D2 (sulpiride 25 ng/side) antagonists that were ineffective alone in disrupting object displacement. Separate groups were then focally injected with a combination of one of the glutamate antagonists with one of the dopamine antagonists. Twenty-four hours later, the ability of mice to discriminate object displacement was assessed.Results Controls and mice injected with ineffective doses of the NMDA, the AMPA, the D1 or the D2 antagonists were always able to react to the object displacement. On the contrary, the groups administered with the different combinations (AP-5 and SCH23390, AP-5 and sulpiride, DNQX and SCH23390, DNQX and sulpiride) of glutamate and dopamine antagonists did not discriminate the spatial change.Conclusions These results demonstrate that glutamate–dopamine receptor interactions within the accumbens are essential for the consolidation process of spatial information. 相似文献
95.
Piras F Colombari R Minerba L Murtas D Floris C Maxia C Corbu A Perra MT Sirigu P 《Cancer》2005,104(6):1246-1254
BACKGROUND: To establish the prognostic value of immune system cells that infiltrate melanoma, the authors evaluated the distribution and density of T lymphocyte subsets, macrophages, and dendritic cells in samples of primary cutaneous melanoma from 47 patients with Stage I and II melanoma according to the American Joint Committee on Cancer staging system. METHODS: Immunohistochemical demonstrations of CD8 and CD4 lymphocytes, CD68 macrophages, human leukocyte antigen-D-related (HLA-DR) cells, S-100 protein, and melanoma-associated antigens Melan A and HMB-45 were performed. The results were derived from independent histopathologic reviews by two pathologists. The low-density, moderate-density, and high-density groups of cells that infiltrated the base of the tumor during the vertical growth phase were compared with the overall survival rate using the Kaplan-Meier method and the log-rank test. Clinical variables (gender, age, tumor location, Clark level, vascular/lymphatic invasion, and thickness) also were analyzed. RESULTS: The CD8 lymphocytes exhibited independent statistically positive significance in survival (log-rank test, 8.49; P = 0.01) between patients in different lymphocyte density groups. There was a difference in 5-year survival among patients in the high-density group (78.8%), the moderate-density group (44.4%), and the low-density group (25.0%). The CD4 lymphocytes, which were less numerous than CD8 cells, had similar distribution. There also was a correlation of HLA-DR cells with overall survival (log-rank test, 5.29; P = 0.02). CD68 cell density was not found to be correlated with survival. CONCLUSIONS: The presence and number of infiltrating CD8 lymphocytes as well as the overall occurrence of HLA-DR cells may be considered independent, favorable prognostic factors in melanoma. The current results may be important for identifying other prognostic factors with which to evaluate disease progression and develop immune therapies for patients with melanoma. 相似文献
96.
PURPOSE: We report our experience with early 1-stage Passerini-Glazel feminizing genitoplasty with special emphasis on long-term results of vaginoplasty. MATERIALS AND METHODS: A total of 66 patients with ambiguous genitalia underwent 1-stage Passerini-Glazel feminizing genitoplasty. Long-term followup included an outpatient visit at 1 year postoperatively and a genital assessment with the patient under general anesthesia performed before menarche courses in those operated on at age 6 months to 8 years, and at 2 years postoperatively for those operated on at 9 years or older. RESULTS: All patients underwent the first long-term followup evaluation and no major complications were observed. The second long-term followup evaluation was performed in 46 patients (70%). In all cases the vaginal introitus was located in the physiological position and was large and elastic. Vaginal caliber at the suture line between the tubularized flap and vaginal mucosa was the same size as the vaginal introitus and distal native vagina in 20 of 46 patients (43%), slightly smaller in 10 (22%) and stenotic in 16 (35%). Stenosis at the suture line was corrected with simple Y-V introitoplasty performed at the same followup visit. CONCLUSIONS: Early 1-stage Passerini-Glazel feminizing genitoplasty is a safe and effective procedure that allows total surgical correction of ambiguous genitalia in infancy and good cosmetic results. Incidence of vaginal stenosis at the suture line is high but it can be repaired with simple introitoplasty performed before menarche occurs. Good functional results are presumed. 相似文献
97.
Gasbarri A Pompili A Arnone B d'Onofrio A Marchetti A Tavares MC Tomaz C 《Functional neurology》2005,20(4):157-162
Psychological and pharmacological studies in humans suggest that emotional arousal enhances long-term memory. In this paper we used, in an Italian sample, an adaptation of a paradigm previously utilized in American samples to study the relationship between emotion and long-term memory. Seventy-two healthy adults from different educational backgrounds were randomly assigned either to a neutral group or to an emotional arousal group and then told a short story, presented audio-visually. In both groups, the slides shown and the slide sequence were the same, and the images were accompanied by a narrative. The two versions of the story differed primarily in their emotional content. Shortly after viewing the slide presentation, the participants were asked to rate the emotionality of the narrative, and ten days later were submitted to a retention test. The emotionally-arousing version of the story was rated as more emotional than the neutral one. Compared with the members of the neutral group, the subjects in the arousal group recalled a significantly higher number of elements from the story. There was no overall difference between the two groups in performance on the recognition memory test. These results confirm that the emotional content of stimuli enhances long-term declarative memory of those stimuli, and indicate the possible usefulness of applying the paradigm utilized in this study to different clinical samples from various cultural backgrounds. 相似文献
98.
OBJECTIVES: Risk factors for intracranial hemorrhage occurring in prenatal life are imperfectly known. A case of prenatal diagnosis of subdural hemorrhage associated with multiple intracranial vascular aneurysms is described. METHODS: Sonography and magnetic resonance imaging of the fetal head were obtained at 21 weeks' gestation and compared with pathologic findings. RESULTS: Sonography showed a large transonic mass displacing the normal intracranial structures. Magnetic resonance imaging demonstrated the hemorrhagic origin of the mass and showed multiple vascular anomalies. Postmortem examination confirmed the compression of the cerebral hemisphere by a blood collection, probably because of bleeding from one of the multiple vascular aneurysms into the subdural space. CONCLUSION: Magnetic resonance imaging with the use of single-shot ultrafast sequences may be useful not only in the differential diagnosis of fetal intracranial hemorrhage but also in identifying vascular risk factors. 相似文献
99.
Vennarecci G Boschetto A Esposito A Giovannelli L Buscaglia F Corazza V Santoro R Mancini P Lorusso R Marino M Ettorre GM 《Chirurgia italiana》2004,56(6):865-868
The authors report the case of a malignant haemangiopericytoma found in an uncommon location, namely the mesorectum. Haemangiopericytomas of the mesorectum are rare mesenchymal tumours of vascular origin that usually occur in the musculature of the extremities, retroperitoneum, pelvis (uterus, ovary and urinary bladder), head, neck and lungs. Rare sites include the liver, pancreas, stomach and greater omentum. Because of their rarity the overall experience has not been significant and little has been published concerning such tumours. In addition, the difficult interpretation of the histological evidence and the poor prognosis of the disease may still give rise to problems in terms of clinical management. Haemangiopericytomas of the retrorectal space, however, seem to behave like malignant tumours: the clinical course is poor and survival short, despite radical surgery, due to early distant metastases and local recurrence. Surgery still remains the mainstay of treatment. Adjuvant therapies should be considered. 相似文献
100.
Li Pira G Bottone L Ivaldi F Pelizzoli R Del Galdo F Lozzi L Bracci L Loregian A Palù G De Palma R Einsele H Manca F 《International immunology》2004,16(5):635-642
CD8 and CD4 lymphocytes control cytomegalovirus (CMV) infection in immunocompetent individuals, while patients with defective cellular immunity are prone to endogenous reactivation of latent CMV or, like seronegative subjects, prone to primary infection. Administration of CMV-specific CD8 lymphocytes was beneficial for immunocompromised hemopoietic stem cell (HSC) graft recipients. Since CD4 cells contribute to expansion of cytotoxic T lymphocytes (CTL), we defined new T(h) peptides on the immunodominant protein pp65 recognized by CD4 cells from HLA-typed subjects, in the perspective of complementing CTL administration with CMV-specific T(h) cells. Screening by ELISPOT on CD4 and CD8 subsets using overlapping peptides identified 10 novel CD4 peptides. To simplify procedures to generate T cell lines, we used a CD4 peptide library for T cell stimulation instead of ill-defined viral lysates, without the requirement of dendritic cells. This library stimulated CMV-specific CD4 cells. In fact, peptide-induced CD4 cells responded to pp65 and to the viral lysate. These cells were also devoid of alloreactivity after one stimulation cycle. Since Good Manufacturing Procedure-grade peptides can be synthesized, culture conditions are simplified and alloreactivity is rapidly lost, these procedures based on peptide stimulation can facilitate implementation of adoptive reconstitution of CD4 responses in immunocompromised patients also in the case when the HSC allodonor is available for generation of the T cell line. 相似文献