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141.
One of the most significant advances in melanoma staging is sentinel lymph node biopsy (SLNB). It is a surgical technique to detect occult nonpalpable micrometastases in regional lymph nodes. Recently, contrast-enhanced ultrasound (CEUS) was introduced as a noninvasive procedure, in spite of SLNB, for the detection of SLNs in patients with cutaneous melanoma. The main purpose of this study was to evaluate the diagnostic accuracy of CEUS in the diagnostic workup of patients with melanoma in comparison with the final histology of SLNs detected through preoperative lymphoscintigraphy. Fifteen patients with cutaneous melanoma underwent prompt excisional biopsy with narrow margins in order to avoid impairment of the melanoma lymphatic basin and were referred for SLNB according to routine indications between January and February 2009. In our study CEUS showed, albeit based on a small patient sample, a negative predictive value of 100%, that means that all negative results were confirmed by negative SLN histopathological examination; all ultrasonographically negative lymph nodes corresponded to nonmetastatic sentinel nodes.  相似文献   
142.
Recent evidence suggests that patients with severe hemophilia B may have a less severe disease compared to severe hemophilia A. To investigate clinical, radiological, laboratory and histological differences in the arthropathy of severe hemophilia A and hemophilia B, 70 patients with hemophilia A and 35 with hemophilia B with at least one joint bleeding were consecutively enrolled. Joint bleedings (<10, 10–50, >50), regimen of treatment (prophylaxis/on demand), World Federation of Hemophilia, Pettersson and ultrasound scores, serum soluble RANK ligand and osteoprotegerin were assessed in all patients. RANK, RANK ligand and osteoprotegerin expression was evaluated in synovial tissue from 18 hemophilia A and 4 hemophilia B patients. The percentage of patients with either 10–50 or more than 50 hemarthrosis was greater in hemophilia A than in hemophilia B (P<0.001 and P=0.03, respectively), while that with less than 10 hemarthrosis was higher in hemophilia B (P<0.0001). World Federation of Hemophilia (36.6 vs. 20.2; P<0.0001) and ultrasound (10.9 vs. 4.3; P<0.0001) score mean values were significantly higher in hemophilia A patients. Serum osteoprotegerin and soluble RANK ligand were decreased in hemophilia A versus hemophilia B (P<0.0001 and P=0.006, respectively). Osteoprotegerin expression was markedly reduced in synovial tissue from hemophilia A patients. In conclusion, the reduced number of hemarthrosis, the lower World Federation of Hemophilia and ultrasound scores, and higher osteoprotegerin expression in serum and synovial tissue in hemophilia B suggest that hemophilia B is a less severe disease than hemophilia A. Osteoprotegerin reduction seems to play a pivotal role in the progression of arthropathy in hemophilia A.  相似文献   
143.
Summary Thin section, tracer, and freeze-fracture experiments demonstrate that the infection caused by molluscum contagiosum virus implies alterations of cellular contacts in the epidermis, never before observed in cutaneous viroses. These changes are basically represented by a distinctive variation in particle apcking of gap junctions, a great proliferation of these junctions and the presence of a high amount of intracytoplasmic gap junctions.Skin tumors caused by molluscum contagiosum virus appear to be a convenient model to study the morphological and topological variations as well as the turnover of gap junctions in the epidermis.This study was presented in part at the 6th meeting of the Society of Cutaneous Ultrastructure Research, Barcelona, June 7–9 1979  相似文献   
144.

Background and purpose

It is still debated whether the COVID-19 pandemic affected disease activity in people with autoimmune diseases, including multiple sclerosis (MS). The aim of this study, therefore, was to explore the impact of COVID-19 in people with MS (pwMS) not receiving continuative disease-modifying therapy (DMT) after previous treatment with autologous hematopoietic stem cell transplantation (AHSCT).

Materials and methods

We included pwMS treated with AHSCT who were in disease remission without receiving DMTs during the pandemic and who were followed up at our centre during the study period. Data on SARS-CoV-2 infection and vaccination were recorded, with details of adverse events and clinical-radiological disease activity.

Results

A total of 36 pwMS (31 females; 86%) were included, of whom 23 (64%) had relapsing-remitting (RR-MS) and 13 had secondary progressive MS (SP-MS). Thirty-three pwMS (92%) received anti-SARS-CoV-2 mRNA vaccines. Thirteen patients (36%) developed mild to moderate COVID-19 a median (range) of 58 (4–224) months after AHSCT; seven (54%) of these patients were not yet vaccinated. Transient neurological symptoms after vaccination or infection were reported in 9% and 36% of the patients, respectively. The rate of new inflammatory events (relapses or asymptomatic magnetic resonance imaging [MRI] activity) after AHSCT increased from 0.006 (one asymptomatic new lesion/159 patient-years) before the pandemic to 0.083 (five relapses plus two cases of asymptomatic MRI activity/84 patient-years) since the pandemic start (p = 0.004).

Conclusions

People with MS with a history of highly active disease, who are untreated or receiving moderate-efficacy DMTs might be more vulnerable to disease reactivation, possibly elicited by exogenous triggers. Careful monitoring and further investigation are warranted to ascertain whether special precautions are needed in these cases.  相似文献   
145.
Irinotecan is a topoisomerase inhibitor, widely used in treatment of malignancies including pancreatic ductal adenocarcinoma (PDAC) as part of the FOLFIRINOX regimen prescribed as a first‐line treatment in several countries. However, irinotecan has not been successfully introduced as a second‐line treatment for pancreatic cancer and few randomized clinical studies have evaluated its added value. Efficacy of liposomal irinotecan (nal‐IRI) combined with 5‐fluorouracil and leucovorin (5‐FU/LV) was reported in the phase III NAPOLI‐1 trial in metastatic PDAC following failure of gemcitabine‐based therapy. Several features of nal‐IRI pharmacokinetics (PK) could result in better outcomes versus nonliposomal irinotecan. Irinotecan is a prodrug that is converted to active SN‐38 by carboxylesterase enzymes and inactivated by cytochrome P450 3A4/3A5. SN‐38 is inactivated by UGT1A1 enzymes. Individual variations in their expression and activity could influence enhanced localized irinotecan activity and toxicity. Liposomal irinotecan exploits the enhanced permeability and retention effect in cancer, accumulating in tumor tissues. Liposomal irinotecan also has a longer half‐life and higher area under the concentration‐time curve (0–∞) than nonliposomal irinotecan, as the liposomal formulation protects cargo from premature metabolism in the plasma. This results in irinotecan activation in tumor tissue, leading to enhanced cytotoxicity. Importantly, despite the longer exposure, overall toxicity for nal‐IRI is no worse than nonliposomal irinotecan. Liposomal irinotecan exemplifies how liposomal encapsulation of a chemotherapeutic agent can alter its PK properties, improving clinical outcomes for patients. Liposomal irinotecan is currently under investigation in other malignancies including biliary tract cancer (amongst other gastrointestinal cancers), brain tumors, and small‐cell lung cancer.  相似文献   
146.
147.
In kittens, callosal axons originating either from medial area 17 (transient axons) or near the 17/18 border (mostly permanent axons) were labelled with anterogradely transported biocytin; they were reconstructed by computer from serial sections, and their morphologies compared at different ages. During the first and second postnatal weeks both sets of axons branched profusely in the white matter of the lateral gyrus and the number of branches increased with age. The most common type of axon ending was the growth cone; others may have been collapsing growth cones, branches in the process of elimination or early synaptic boutons. Axons from medial area 17 distributed over a broad territory, including the 17/18 border where callosal axons terminate in the adult cat, but without aiming specifically at any one area. The majority of axons and their branches terminated in the white matter or at the bottom of layer VI; exceptionally they extended further into the cortex. Most of the axons originating near the 17/18 border were different from those described above, and the difference increased with age. Although they also terminated profusely in the white matter of the lateral gyrus, most of the branches terminated near the contralateral 17/18 border; they frequently entered the grey matter up to the superficial layers and branched into it. During the third week, axons from medial area 17 were rarely found to extend beyond the corpus callosum, probably because they were in the process of being eliminated. In contrast, axons originating near the 17/18 border had increased their number of branches in the grey matter. In conclusion, during the first and second postnatal weeks axons grew and differentiated according to their origin, and this anticipated whether they would be maintained or eliminated. Neurotrophic signals, possibly from the white matter or the subplate, and growth-inhibiting signals from area 17 may be involved in this process.  相似文献   
148.
To evaluate whether the combination of nifedipine with chlorthalidone exerts an additive antihypertensive effect when compared to single-drug treatment, 66 uncomplicated essential hypertensives, whose diastolic blood pressure was greater than 100 and less than 115 mm Hg at the end of a 1-month washout placebo period, received, according to a randomized, double-blind, crossover design, nifedipine (20 mg b.i.d.), chlorthalidone (25 mg o.d.), the two drugs combined at the same doses, and the corresponding placebo. When compared to the randomized placebo the three active treatments significantly (p less than 0.001) reduced blood pressure without changing heart rate and body weight. However, blood pressure values were similarly reduced under nifedipine and the combination and were significantly lower (p less than 0.05) than those under chlorthalidone. Moreover, the percentage of responders and normalized patients under nifedipine and the two drugs combined were similar and significantly (normalized, p less than 0.0001; responders, p less than 0.02) greater than those under chlorthalidone. Under chlorthalidone and its combination with nifedipine, plasma potassium tended to decrease and blood glucose and serum uric acid were significantly (p less than 0.05) increased. These data show that the combination of nifedipine with chlorthalidone does not exert any additive antihypertensive effect when compared to nifedipine alone and that this combination increases both blood glucose and serum uric acid. Taken together these findings indicate that the combination of a dihydropyridine calcium antagonist with a thiazide diuretic is devoid of any clinical significance in the treatment of uncomplicated essential hypertensives.  相似文献   
149.
A 48-year-old parquet floor layer suffered from an attack of asthma at work and systemic toxic reaction after exposure to cabreuva wood dust (Myrocarpus fastigiatus Fr. All.). Exposure to the same dust in hospital produced a late asthmatic reaction with fever, vomiting and myalgia. Leucocytosis with neutrophilia was present after a bronchial provocation test but no radiological changes were observed. A control bronchial provocation test with fir wood dust was negative. It was not possible to study the systemic toxic reaction further due to non-collaboration of the patient; nevertheless, these findings show that systemic reactions to wood dust should always be investigated even though their occurrence is fortunately rare.  相似文献   
150.
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