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1.
BACKGROUND: Since 1997, a number of trials have shown promising results in treating generalized vitiligo with narrowband ultraviolet B (UVB) both in adults and children. However, there is little knowledge concerning the duration and permanency of the treatment-induced repigmentation. OBJECTIVE: Our main objective was to perform a follow-up trial of successfully treated patients receiving narrowband UVB for generalized vitiligo. METHODS: We have investigated to what degree the treatment-induced repigmentation remains stable for up to 2 years post-treatment. We performed an initial open trial including 31 patients with generalized vitiligo. They received narrowband UVB thrice weekly for up to 12 months. Patients experiencing > 75% repigmentation were defined responders and were included in the follow-up trial. Responders were followed every 6 months for up to 2 years after cessation of treatment. We observed the pigmentation status and registered any changes indicating loss of pigmentation and relapse. RESULTS: Eleven of the 31 treated patients were included in the follow-up trial. Six patients had relapse and five patients had stable response 24 months after cessation of treatment. Four out of six relapses were within 6 months post-treatment. CONCLUSION: In our study population of 31 patients with generalized vitiligo, five patients (16%) experienced > 75% stable repigmentation 2 years after cessation of a treatment programme of up to 1 years narrowband UVB therapy.  相似文献   
2.
To assess adrenal medulla activity in states of hyperfunction, a single 0.3 mg oral dose of clonidine hydrochloride (Catapres) was given to twelve patients with varying evidence of familial adrenal medullary hyperplasia and pheochromocytomas from kindreds with Multiple Endocrine Neoplasia type 2 syndrome (MEN-2), seven patients with sporadic pheochromocytomas and six normal subjects. Mean arterial blood pressure and plasma norepinephrine (NE) levels were lower than baseline values 2 h after clonidine in the normal subjects. Plasma epinephrine (E) rose in one normal but fell in the remainder after clonidine administration. In sporadic pheochromocytoma patients, E fell slightly in 4 and NE fell in 3 while mean arterial blood pressure was not significantly lower than baseline values in 7 patients 2 h after clonidine. In MEN-2, mean arterial blood pressure fell and there was a variable response of plasma E and NE to clonidine, which appears to be related to the presence of detectable anatomic (CT scan) and functional (131I-mlBG scintigraphy) abnormalities of the adrenal medulla. These findings are thus compatible with the spectrum of adrenal medulla dysfunction and the presumed development of pheochromocytoma in this syndrome.  相似文献   
3.
Birnholz  JC 《Radiology》1986,158(3):805-807
Ultrasound (US) can be used to visualize vertebral segments, suggesting a quantitative means of studying vertebral column growth in utero and thus a means of detecting developmental abnormalities. US images of the lumbar spine were obtained in 128 clinically normal fetuses between the gestational age of 11 through 41 weeks. A large-aperture, dynamically focused US system capable of regional magnification was used. Average lumbar spacing was calculated from distance between centrums of at least four lumbar bodies. The average distance between lumbar centrums increased nearly linearly throughout the second and third trimesters (r2 = 0.98). Enhanced anatomic display implies new capabilities for recognizing developmental abnormalities antenatally.  相似文献   
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5.
Male genital oedema can be defined as swelling or the appearance of swelling of the scrotum and/or the penile shaft and prepuce. Despite the various causes of genital oedema reported in the published work, a concise approach to the evaluation and management has not been sufficiently addressed.  相似文献   
6.
Encapsulated Staphylococcus aureus strains are more virulent than unencapsulated staphylococci, and this phenomenon has been associated with decreased opsonization of encapsulated bacteria by normal human serum. Peptidoglycan, a major cell wall component of S. aureus, has been shown to promote opsonization of this bacterial species by certain components of the serum complement system. However, when the processes of complement activation and opsonization of encapsulated staphylococci have been studied, it has been found that encapsulated bacteria activate complement efficiently and C3 is bacteria associated, yet these organisms are not efficiently phagocytized by human polymorphonuclear leukocytes. In this study, the hypothesis was tested that opsonically active molecules are not on the true external surface of encapsulated organisms but rather are cell wall associated and thus "hidden" from human polymorphonuclear leukocytes. By using immunoelectronmicroscopy, C3 was found to be localized on the cell wall of an encapsulated S. aureus strain after incubation of the organism in normal human serum. When shrinkage of the capsule was prevented by treatment with anticapsular antibody, the C3 was again shown to be cell wall associated and located beneath the bacterial capsule. These results suggest that encapsulated S. aureus may resist phagocytosis because opsonically active C3 molecules are not exposed at the true external surface of the bacterium.  相似文献   
7.
Innate defense against microbial infection requires the action of neutrophils, which have cytoplasmic granules replete with antibiotic proteins and peptides. Bactericidal/permeability-increasing protein (BPI) is found in the primary granules of adult neutrophils, has a high affinity for lipopolysaccharides (or "endotoxins"), and exerts selective cytotoxic, antiendotoxic, and opsonic activity against gram-negative bacteria. We have previously reported that neutrophils derived from newborn cord blood are deficient in BPI (O. Levy et al., Pediatrics 104:1327-1333, 1999). The relative deficiency in BPI of newborns raised the possibility that supplementing the levels of BPI in plasma might enhance newborn antibacterial defense. Here we determined the effects of addition of recombinant 21-kDa N-terminal BPI fragment (rBPI(21)) on the growth and tumor necrosis factor (TNF)-inducing activity of representative gram-negative clinical isolates. Bacteria were tested in citrated newborn cord blood or adult peripheral blood. Bacterial viability was assessed by plating assay, and TNF-alpha release was measured by enzyme-linked immunosorbent assay. Whereas adult blood limited the growth of all isolates except Klebsiella pneumoniae, cord blood also allowed logarithmic growth of Escherichia coli K1/r and Citrobacter koseri. Bacteria varied in their susceptibility to rBPI(21)'s bactericidal action: E. coli K1/r was relatively susceptible (50% inhibitory concentration [IC(50)], approximately 10 nM), C. koseri was intermediate (IC(50), approximately 1,000 nM), Klebsiella pneumoniae was resistant (IC(50), approximately 10,000 nM), and Enterobacter cloacae and Serratia marcescens were highly resistant (IC(50), >10,000 nM). All isolates were potent inducers of TNF-alpha activity in both adult and newborn cord blood. In contrast to its variable antibacterial activity, rBPI(21) consistently inhibited the TNF-inducing activity of all strains tested (IC(50), 1 to 1,000 nM). The antibacterial effects of rBPI(21) were additive with those of a combination of conventional antibiotics typically used to treat bacteremic newborns (ampicillin and gentamicin). Whereas ampicillin and gentamicin demonstrated little inhibition of bacterially induced TNF release, addition of rBPI(21) either alone or together with ampicillin and gentamicin profoundly inhibited release of this cytokine. Thus, supplementing newborn cord blood with rBPI(21) potently inhibited the TNF-inducing activity of a variety of gram-negative bacterial clinical pathogens and, in some cases, enhanced bactericidal activity. These results suggest that administration of rBPI(21) may be of clinical benefit to neonates suffering from gram-negative bacterial infection and/or endotoxemia.  相似文献   
8.
Characteristics of motile curved rods in vaginal secretions   总被引:7,自引:0,他引:7  
Motile curved rods seen in vaginal secretions have been isolated on Columbia agar supplemented with 5% human blood and vitamin K. Growth occurred anaerobically and in 5% oxygen but not in more aerobic conditions. There were two distinct groups of these organisms, distinguishable by morphology, biochemical activity and susceptibility to metronidazole. All isolates were sensitive to a wide range of antimicrobial agents, with the exception of nalidixic acid and polymyxin, but one group was resistant to metronidazole. There was little difference between the results of tests of susceptibility to aminoglycosides or to metronidazole performed in anaerobic and microaerophilic conditions. Motile curved rods were isolated from 18 of 80 patients with a clinical diagnosis of non-specific vaginitis, but from only two of 39 without the disease.  相似文献   
9.
Summary The anatomic constraints imposed on a total artificial heart (TAH) require specific anatomic studies. A thoracic anatomic study was performed with a scanning device equipped with three-dimensional (3-D) reconstruction software on 15 male patients, between the ages of 41 to 63 years (52 ± 6 years). All were candidates for heart transplantation. The 3-D reconstructions of the cardiovascular structures obtained from surgical anatomy data specific to TAH implantation allowed a volumetric measurement of these structures. A modeling diagram of these structures permitted reproducible quantitative measurements of the 35 geometrical parameters which characterized shape, orientation, and position of these structures within the thorax. Most of the measured parameters were characterized by low variability (coefficient of variation from 10 to 25%).
Modélisation tridimensionnelle de l'anatomie du cur et des gros vaisseaux
Résumé Les contraintes anatomiques imposées au cur artificiel total (CAT) nécessitent des études anatomiques spécifiques. Une étude anatomique thoracique a été réalisée avec un scanner doté d'un logiciel de reconstruction tridimensionnelle (3-D) chez 15 patients, tous de sexe masculin, agés de 41 à 63 ans (52 ± 6 ans), et candidats à une transplantation cardiaque. Les reconstructions 3-D des structures cardio-vasculaires réalisées selon les données de l'anatomie chirurgicale propre à l'implantation du CAT ont permis la mesure volumétrique de ces structures. Un schéma de modélisation de ces structures a permis des mesures quantitatives reproductibles de 35 paramètres géométriques caractéristiques de la forme, de l'orientation, de la position de ces structures dans le thorax. Les résultats de ces mesures ont pu être exprimés en termes statistiques. La plupart des paramètres mesurés étaient caractérisés par une faible variabilité (coefficients de variations de 10 à 25%).
  相似文献   
10.
Increased antiphospholipid antibody prevalence has been demonstrated by a number of recent studies in in-vitro fertilization (IVF) patients but the potential effects of antiphospholipid antibodies on the different components of the reproductive process and the consideration of whether to test IVF patients for antiphospholipid antibodies are controversial. The present study was undertaken to investigate the possible association between the presence of circulating antiphospholipid antibodies (namely the lupus anticoagulant and anticardiolipin antibodies), among a series of 21 consecutive IVF patients having a clinical spontaneous abortion after their first embryo transfer. As a control group (n=42), the nearest IVF cycle resulting in an ongoing pregnancy before and after each miscarried IVF cycle (i.e. the closest cycles in temporal relationship to the index cycle) was used. One patient (4.8%) in the study group and two women (4.8%) among controls were seropositive for antiphospholipid antibodies. These low and similar seropositivity rates found in the two groups studied lead us to conclude that antiphospholipid antibodies testing in IVF patients should be considered only in those women having repeated failures of implantation/clinical abortion after embryo transfer but not in an infertile general population reaching an IVF programme.   相似文献   
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