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1.
Over the last decade, impressive technological advances have occurred in ultrasonography and small‐bowel endoscopy. Nowadays, endoscopic ultrasonography is an essential diagnostic tool and a therapeutic weapon for pancreatobiliary disorders. Capsule endoscopy and device‐assisted enteroscopy have quickly become the reference standard for the diagnosis of small‐bowel luminal diseases, thereby leading to radical changes in diagnostic and therapeutic pathways. We herein provide an up‐to‐date overview of the latest advances in endoscopic ultrasonography and small‐bowel endoscopy, focusing on the emerging paradigms and technological innovations that might improve clinical practice in the near future.  相似文献   
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A patient with HIV infection developed the first episode of AIDS-defining opportunism (severe Candida albicans esophagitis) with an underlying CD4+ lymphocyte count of 1,025 cells/microL. After treatment with a highly active antiretroviral therapy (HAART), taken with insufficient compliance and leaving a residual viral load, our patient suffered from two relapses of esophageal candidiasis, which occurred three months and seven years later, when his CD4+ lymphocyte count was 930 and 439 cells/microL, respectively, and a viral load slightly above 10(4) copies/mL was still present. Also in the HAART era, Candida esophagitis remains one of the most common AIDS-defining diseases, but a presentation with a concurrent CD4+ count above 1,000 cells/microL remains a rare exception, as well as the two isolated, subsequent relapses, occurred with a CD4+ count ranging from 439 to 930 cells/microL, and a residual HIV viremia due to insufficient adherence to the prescribed HAART regimens. Our case report represents the opportunity to revisit the epidemiology and, especially, the pathogenesis of this opportunistic fungal complication in HIV-infected patients and in other subjects at risk, on the ground of an extensive literature review, and to explore possible alternative supporting factors other than the crude absolute CD4+ lymphocyte count, with emphasis on the possible role of a persisting HIV viremia, and other potential contributing factors. Clinicians engaged with immunocompromised patients and subjects with HIV disease, should be aware that a Candida esophagitis may occur and relapse also when the cell-mediated immunity, as measured by a simple CD4+ cell count, do not show relevant abnormalities.  相似文献   
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To increase our understanding of Candida pathogenicity, the identification of those strains most frequently associated with infections is of paramount importance. Polymerase chain reaction (PCR)‐based methods are extremely effective in differentiating and determining reproducibility, they require minimum starting material and are rapid and simple to perform. In this study, the genetic relatedness of Candida albicans was assessed for two geographically different patient groups (London, UK and Parma, Italy) affected by diabetes mellitus. C. albicans samples from the oral cavities of non‐diabetic healthy subjects were also examined by PCR fingerprinting to evaluate the possible genetic differences among endogenous strains in individuals with and without diabetes mellitus. PCR fingerprinting, with subsequent phylogenetic analysis of C. albicans isolates from the diabetic patients from London and Italy and from the non‐diabetic subjects, revealed that there were significant differences (P < 0.0001) between C. albicans isolates indicative of the distinct ecological niches that occur in the oral cavities of these patient cohorts. The most diverse group comprised the isolates from the diabetic patients in the UK, possibly reflecting the antifungal treatment that these patients had received. Further studies that include isolates from patient cohorts with systemic diseases other than diabetes mellitus, and from more diverse geographic localities are required to explain the relatedness of C. albicans isolates in the mouth.  相似文献   
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We report the case of a patient with a 13-year history of pemphigus vulgaris (PV) treated with immunosuppressive agents, prednisone and mycophenolate mofetil who had developed lesions of Kaposi's sarcoma (KS) on a sole plaque of PV that had been previously treated with intralesional injections of steroids. The lesions were surgically removed and polymerase chain reaction (PCR) demonstrated human herpesvirus-8 (HHV-8) DNA. There were neither recurrences nor later dissemination of KS following gradual decrease of the immunosuppressive therapy. We suggest that the treatment with intralesional steroids may have influenced the local reactivation of a latent infection of the virus, determining the appearance of this localized KS.  相似文献   
6.
The purpose of this study was to provide, in a large number of patients, comprehensive Doppler echocardiographic assessment of normal St Jude Medical mitral valve prosthesis function using Doppler-derived hemodynamic variables, including the mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio and prosthesis performance index. The pressure half-time was less than 130 milliseconds in all patients, and all but one patient had either a peak early mitral diastolic velocity of 2 m/s or less or a mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio of less than 2.2. There was a significant (P < .001) negative correlation between the prosthesis performance index and prosthesis size. This negative correlation suggests that there is more efficient use of the in vitro geometric orifice area with smaller prostheses.  相似文献   
7.
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
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We investigated the neurophysiological and clinical effects of repetitive magnetic stimulation (rTMS) delivered to the cortical motor areas in healthy subjects and patients with Parkinson's disease. rTMS was delivered with a high speed magnetic stimulator (Cadwell, Kennewick, WA) through a figure-eight coil centred on the primary motor area at a stimulus intensity of 120% motor threshold. Trains of 10 stimuli were delivered at frequencies of 5 Hz while subjects were at rest and during a voluntary contraction of the contralateral first dorsal interosseous muscle. In normal subjects at rest, the muscle evoked responses (MEPs) to each stimulus in a train of magnetic stimuli progressively increased in size during the train. rTMS left the MEPs unchanged in patients off therapy and had a small facilitatory effect in those on therapy. In normal subjects and patients, 5-Hz rTMS trains delivered during a voluntary contraction of the target muscle left the MEP unchanged in size. MEPs were followed by a silent period that increased in duration during the course of the train. The silent period duration increased to a similar extent in patients and controls. The reduced rTMS-induced facilitation of MEPs in patients with Parkinson's disease reflects a decreased facilitation of the excitatory cells in the cortical motor areas.  相似文献   
10.
The alpha subunit of the nicotinic acetylcholine receptor (AChR) seems crucial in the pathogenesis of the autoimmune paralysis myasthenia gravis (MG) because it contains both the epitopes that dominate the antibody response against the AChR and those recognized by CD4+ AChR-specific T helper (Th) cells. To define the repertoire of anti-AChR Th cells, we investigated the response of unselected blood CD4+ cells or total lymphocytes, or both, from 22 MG patients to 20-residue overlapping synthetic peptides, screening the complete sequence of human-muscle AChR alpha subunit. Several epitopes were identified. Only the most severely affected patients recognized alpha subunit epitopes, and they were mainly young women. Detection of in vitro AChR-specific CD4+ response was facilitated by removal of the CD8+ cells because in two patients a clear response to several alpha subunit peptide sequences could be detected when CD(8+)-depleted cells were used, while their total peripheral blood mononuclear cell population did not respond to any alpha subunit peptide. Although each patient had a unique pattern of peptide recognition, four immunodominant regions recognized by long-term AChR-specific CD4+ T-cell lines, or flanking peptide sequences, were recognized most frequently (residues 48-67, 101-137, 293-337, and 308-437).  相似文献   
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