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31.
In this study, our objective was to evaluate Etest strips containing exponential gradients of isoniazid (INH), rifampin (RIF), and streptomycin (STR) for susceptibility testing of Mycobacterium tuberculosis. M. tuberculosis isolates were tested for antimicrobial susceptibilities by the standard proportion method using L?wenstein-Jensen (LJ) medium and by the Etest. The MICs determined by the Etest were obtained at 5, 7, or 10 days. In some strains with Etest-discrepant results, radiometric susceptibility testing (BACTEC) was performed to determine a consensus result. M. tuberculosis concordance between the two methods was 97% (86 of 89 isolates) for RIF, 96% for INH (84 of 87 isolates), and 80% (61 of 76 isolates) for STR. Most of the MICs determined by the Etest were easy to interpret and readable within 5 days. Results correlated well with those obtained by the LJ proportion and BACTEC methods for INH and RIF. However, a high proportion of false-sensitive and false-resistant results were observed, most often for STR. We also observed that variations in the inoculum size of M. tuberculosis isolates affected the MICs to a substantial degree. These discrepancies, along with the expense of the media, the Etest strips, and the specialized equipment required (CO2 incubator), make this method less useful in developing countries.  相似文献   
32.
Loxoscelism, the term used to describe envenomation with brown spiders, is characterized by a dermonecrotic lesion at the bite site. In the present investigation we submitted albino rabbits to an acute experimental envenomation protocol using Loxosceles intermedia (brown spider) venom, with in order to determine the pathogenesic features of the lesion induced by this spider, which is the cause of several accidents throughout the world. Rabbits received intradermal injections of the venom and were monitored over the first 4 h, and then at 12 h and 1, 2 and 5 days after envenomation. Histological specimens from 3 rabbits per time point were collected from euthanized animals and processed for histological examination by light microscopy. Major findings observed during the first 4 h were oedema, haemorrhage, degeneration of blood vessel walls, plasma exudation, thrombosis, neutrophil accumulation in and around blood vessels with an intensive diapedesis, a diffuse collection of inflammatory cells (polymorphonuclear leucocytes) in the dermis, and subcutaneous muscular oedema. Over the following hours and up to 5 days after envenomation the changes progressed to massive neutrophil infiltration (with no other leucocytes) into the dermis and even into subcutaneous muscle tissue, destruction of blood vessels, thrombosis, haemorrhage, myonecrosis, and coagulative necrosis on the 5th day.  相似文献   
33.
Rats bearing lesions in the septal area followed by lesions in the subfornical organ were submitted to various thirst-eliciting procedures. The rats with hyperdipsia induced by lesions of the septal area drank more water than either during the control period or after lesion of the subfornical organ under the same thirst-eliciting or angiotensin-liberating stimuli (polyethyleneglycol, isoproterenol, water deprivation and ligation of the inferior vena cava). The overdrinking elicited by lesions in the septal area was blocked after lesion of the subfornical organ. Neither hypovolemia, nor hypotension or water deprivation could elicit increased water intake in animals whose subfornical organ had been destroyed. Animals with lesions in the subfornical organ showed decreased water intake after cellular dehydration. The results obtained suggest that the subfornical organ acts as a more important structure than the septal area in the regulation of water intake elicited by angiotensin, with two opposite effects: a direct one facilitating water intake, and an indirect one inhibiting the septal area. The septal area has an inhibitory effect on the subfornical organ and on water intake.  相似文献   
34.
AimThe aim of this study is to present our experience in the management of hormonally active adrenal tumors in children.Material and methodsWe did a retrospective chart review of all children with hormonally active adrenal tumors evaluated at the endocrinology clinic and operated at our institution between 1983 and 2019.ResultsThere were 75 patients included in the study, 58 with adrenocortical tumors (ACTs) and 17 with pheochromocytomas (PCCs). Within the group of patients with ACTs, there were 41 females and 17 males. The mean age was 58.3 (SD: 87.9; range: 9–211) months. The clinical manifestation of the tumor's hormonal activity was virilization in 37 cases, Cushing syndrome in 5, and mixed in 16. A positive family history was present in 11 patients (18.9%). The mean tumor size was 48.2 (SD: 22.4; range: 7–120) mm. The pathological diagnosis was adenoma in 42 cases, carcinoma in 15 cases, and macronodular hyperplasia in 1. Median follow-up was 192 (range: 50–290) months. Tumor recurrence occurred in 6 patients (10.3%), and there were three disease-related deaths (5%). Within the group of patients with PCCs, there were 11 males and 6 females. The mean age was 146.7 (SD: 71.2; range: 60–216) months. A positive family history was present in 7 patients (41.2%). The mean tumor size was 36.6 (SD: 16.7; range: 7–120) mm. The pheochromocytoma was classified as benign in 15 cases and as malignant in 2. During a median follow-up of 180 (range: 127–300) months, recurrence was observed in 6 cases (35.3%) and disease-related death in 1 case (5.9%).ConclusionsProper diagnosis and management at our referral center were associated with a high cure rate, even in cases of malignant tumors. Familial surveillance is highly recommended.Level of evidenceLevel IV.  相似文献   
35.
Pseudoangiosarcomatous squamous cell carcinoma, also called pseudovascular, pseudoangiomatoid or adenoid pseudovascular carcinoma, is an uncommon and highly aggressive variant of squamous cell carcinoma. Histologically, it is characterized by proliferation of atypical keratinocytes with acantholysis and formation of pseudovascular spaces, forming anastomosed channels lined with neoplastic cells that invade the dermis. These cells are positive for cytokeratin and negative for vascular markers such as CD31 and CD34. There are few reports of this variant in the literature. Skin, breast, lung and vulva involvement have been described, but to the best of our knowledge, no cases involving the penis has been described. This study aims to describe the first case of angiosarcomatous squamous cell carcinoma of the penis. The patient presented with a painful lesion in the penis associated with urinary retention. Macroscopic findings exhibited an ulcerative vegetating lesion that involving the entire glans and part of the penile body, as well as infiltration of penile structures and scrotal skin. Microscopy shows atypical proliferation of sarcomatous keratinocyte pattern mimicking vascular spaces. Human papilloma virus (HPV) biomarkers and polymerase chain reaction (PCR) were all negative. Advanced penile squamous cell carcinoma with aggressive lymph node metastasis. This report presents the first case of penile pseudoangiosarcomatous squamous cell carcinoma, as an important differential diagnosis.  相似文献   
36.
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to evaluate the chlorhexidine gluconate (CHG) susceptibility in both planktonic cells and biofilm of...  相似文献   
37.
We report here the treatment and poor outcome of a case of Maple Syrup Urine Disease with late diagnosis and retrieval (2 and 5 months, respectively). As the proband had quite high levels of plasmatic leucine (1956 micromol/L for a normal upper limit of 77), we started immediately with a gluco-insulin therapy to produce anabolism in the infant. When leucine has fallen to 275.3 micromol/L, we instituted feeding with branched chain amino acid-free protein and high energy from carbohydrates. After reviewing briefly the clinical, biochemical and therapeutic aspects of this disorder, we comment on the great difficulties of making early diagnosis and of obtaining the specific dietetic formulas to Maple Syrup Urine Disease, in Brazil.  相似文献   
38.
This is the report of a case with an atherosclerotic splenic artery aneurysm ruptured into the peritoneal cavity which presented with hypovolaemic shock. The patient underwent successfully emergency laparotomy and splenectomy. A brief review of the the literature follows.  相似文献   
39.
40.
BACKGROUND: Several studies comparing the response of acute cellular rejection (ACR) episodes to different corticosteroid regimens have been conducted. However, in most of them, the histological evaluation of the infiltrate and its correlation with clinical response was not studied. The clinical and histological outcomes of 37 episodes of ACR treated with methylprednisolone (MP) were studied, with the aim to determine how long the infiltrate takes to be cleared after therapy. METHODS: A total of 37 patients with biopsy-proven ACR were treated with 8 or 16 mg of MP/kg/day. Allograft biopsies were repeated at 5 and 10 days after the end of corticotherapy. Clinical and histological outcomes were compared. RESULTS: Six patients were excluded; 15 (48.4%) patients responded to therapy; the mean serum creatinine of these patients reached normal levels in the 2 weeks that followed treatment. Nine patients (60%) of this group had signs of ACR on biopsies done 5 days after corticotherapy, and four (26.7%) maintained them on the 10th day. Among 16 patients with no clinical response, none reached normal serum creatinine levels; 15 (93.7%) had signs of rejection 5 days after treatment and maintained them on the 10th day. Histological signs of ACR disappeared in 73.3% of patients with clinical response 10 days after therapy, but in only 6.3% of patients with no response (P=0.001). CONCLUSIONS: Biopsies performed 5 days after treatment show a high incidence of features of ACR; such features take on average 10 days to disappear in nearly 75% of cases with successful therapy with MP.  相似文献   
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