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11.
We report a first case of a 19 year old female suffering from an acute lymphatic leukemia, which developed shortly after the initiation of a chemotherapy an intracerebral hemorrhage and fatal multiple brain abscesses caused by Bacillus cereus. There is much evidence that Bacillus cereus in immunocompromised patients leads to a localized, necrotizing tissue infection due to the production of potent toxins and usually results in rapid and fulminant tissue destruction. Bacillus species has an special affinity for the CNS mediated by phospholipase C, which tends to associate with the lipid membranes of the brain.  相似文献   
12.
Idiopathic bilateral adrenal hemorrhage with thrombosis of both renal veins and inferior vena cava are presented using US and CT in a newborn. To our knowledge such bilateral involvement of the adrenal glands and the renal veins have not been reported previously.  相似文献   
13.
Abdominal Stab Wounds in Children: an 18-Year Experience   总被引:1,自引:0,他引:1  
Objective: Evaluation of the diagnosis, management, and the role of selective treatment in children with abdominal stab wounds. Patients and Methods: 59 children (56 male and three female) were included in the study. The patients' median age was 11.8 years (range, 5–14 years). Time between injury and admission was about 3 h. Laparotomy was performed in 44 patients (74%). Solid organ injury was detected in 32 of these patients (73%) and could not be observed in twelve (27%). 15 patients (26%) were treated conservatively, and only one (6.6%) underwent laparotomy during the follow-up. The stomach was the most frequently injured organ (ten patients), followed by the intestines (nine patients). Types of surgical treatment were as follows: primary suture in 28 patients, resection-anastomosis in three, and osteotomy in two. Results: Some prognostic factors such as presence of abdominal organ evisceration and pneumoperitoneum were not significantly correlated with intraabdominal organ injury, whereas some other risk factors such as acute abdomen on admission (p < 0.002) or abdominal clinical and hemodynamic findings (p < 0.001) showed significant correlation with intraabdominal organ injury. The relative risk (odds ratio) of developing an intraabdominal organ injury was > 2 for patients with signs of an acute abdomen on admission. Postoperative complications were observed in five patients with organ injuries. None of our patients died. Conclusions: Conservative treatment can be safely performed in most children with abdominal stab injuries. Signs of major internal hemorrhage or generalized peritonitis are an absolute indication for emergency operation for abdominal stab wounds. Peritoneal penetrations, free air on the abdominal X-ray, and omental or intestinal evisceration are poor indicators of significant organ injuries, and patients presenting these signs shold be closely followed up for developing acute abdominal symptoms. Received: November 2, 2001; revision accepted: February 15, 2002  相似文献   
14.
OBJECTIVE: The aim of this study is to investigate dose-dependent effect of the topical application of methotrexate (MTX) in rats on the normal nasal mucosa, liver tissue, liver enzymes, and hemoglobin levels. STUDY DESIGN: Preclinical animal study. SETTING: Twenty male adult wistar albino rats were randomly divided into 4 groups (n=5). A single puff of MTX (2.5 microg) was applied to both nasal cavities 2 times a day. The animals were given MTX 1 day a week in group 1, 3 days a week in group 2, and 5 days a week in group 3. Control group animals were given 1 puff of physiologic saline to both nasal cavities 5 days a week and 2 times a day. After 28 days, liver biopsies, blood samples, and 5 nasal mucosal biopsies were taken. Histological examination was made with respect to certain parameters semiquantitatively (grade 0-3). The aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and hemoglobin counts were studied from blood samples. RESULTS: There are no statistically significant differences with respect to histopathological parameters between the control group and the groups 1-3 (P>0.05). Histopathological examination of liver tissue did not reveal any evident difference between the control and study groups. Mean AST and ALT as liver function tests and hemoglobin counts were within normal limits. Topical application of MTX at these doses has no toxic effect on the nasal mucosa, the liver tissue, AST and ALT levels, and hemoglobin level. CONCLUSIONS: These results have been encouraging to investigate use of the topical application of MTX in nasal manifestation of autoimmune disease or addition of the topical application of MTX to the steroid treatment in cases with massive nasal polyposis resistant to steroids and prone to recurrence.  相似文献   
15.
BACKGROUND: This study aimed to investigate whether exposure to sunflower pollen (Helianthus annuus) increases both sensitization and respiratory symptoms, and whether or not it affects lung functions in sunflower processing workers. METHODS: The largest sunflower processing factories in the Thrace region of Turkey participated in this study. Workers from the units directly exposed to sunflower seed enrolled as the study group (n = 102) and workers who were not directly exposed to Helianthus annuus pollen (n = 102) were the control group. Detailed questionnaires covering respiratory and allergic symptoms were completed, and skin prick tests and lung function tests were performed. RESULTS: We found a very high rate (23.5%) of sensitization to Helianthus annuus in the study group compared to the controls (P<0.001). Logistic regression analysis showed that the risk of sensitization to H. annuus was increased 4.7-fold (odds ratio = 4.17, 95%) confidence interval = 1.3-16.7) if subjects were exposed to sunflower pollen in the workplace. While asthmatic symptoms and allergic skin diseases were not different between the two groups, workers in the study group had a higher rate of allergic rhinitis and conjunctivitis (P<0.05). We found that pulmonary function was significantly impaired in the study group (P<0.01). Using a multivariate analysis model, inclusion in the study group was found to be a predictive factor for impairment of lung function (P=0.002). CONCLUSIONS: We conclude that sunflower pollen has high allergenic potential, especially when there is close contact, and exposure to sunflower pollen in the workplace can result in impairment in lung function.  相似文献   
16.
Although breast carcinomas have been shown to produce various ectopic substances, including human chorionic gonadotropin, it is rare to identify morphologic differentiation compatible with the hormone produced by a tumor. Presently, only eight cases of breast carcinoma with focal choriocarcinomatous differentiation have been reported in the literature. This article describes the pathologic findings, immunohistochemical profile, and clinical course in two additional cases of this unusual variant of breast carcinoma. In the first case, the tumor had morphologic features suggestive of medullary carcinoma, and the patient is doing well 12 months after presentation. In the second case, the tumor was locally advanced at presentation with histologic features consistent with metaplastic carcinoma having squamous, sarcomatoid, and choriocarcinomatous elements. The patient presented with extensive multifocal metastases 6 months after the initial presentation and is not responding well to standard or experimental treatment regimen. Immunostaining for the beta subunit of human chorionic gonadotropin was localized mostly, but not entirely, to multinucleated syncytiotrophoblast-like giant cells within both tumors.  相似文献   
17.
HER-2/neu peptides have recently been shown to induce a proliferative response by peripheral CD4(+) T cells in breast cancer patients. To investigate potential differences in the local cellular immune response between breast cancer patients with and without nodal metastases, lymphocytes were isolated from axillary lymph nodes from patients with breast cancer, and proliferative and cytokine responses to HER-2/neu peptides were determined. Freshly isolated lymphocytes from lymph nodes of 7 women undergoing surgery for invasive breast cancer were plated at 20 x 10(5) cells per well in triplicate. Cells were stimulated with HER-2/neu peptides at 50 microg/ml and with control antigens. Incorporation of tritium-labeled thymidine was determined 4 days later. The levels of the cytokines interferon-gamma (IFN-gamma), interleukin-4 (IL-4), and IL-10 were determined at priming and at restimulation with HER-2/neu peptides using a cytokine-specific, double-sandwich, enzyme-linked immunosorbent assay (ELISA). Lymphocytes isolated from the axillary lymph nodes of the patients mounted significant cellular immune response to HER-2/neu peptides, manifested by proliferation and specific cytokine elaboration. Proliferative responses to HER-2/neu peptides were seen in lymphocytes of patients with and without overexpression of HER-2/neu in the primary tumor. In some patients, the proliferative response to HER-2/neu peptides in lymphocytes from lymph nodes with metastases was absent or blunted compared with the response in lymphocytes from lymph nodes without metastases from the same patient (p < 0.05). HER-2/neu peptides induced a predominantly T helper type 1 (Th1) pattern of cytokine response in nodal lymphocytes isolated from breast cancer patients. A Th1-specific cytokine production pattern was maintained at priming and restimulation with HER-2/neu peptides and was amplified with IL-12 costimulation. These results indicate that HER-2/neu peptides can activate T cells in draining lymph nodes from women with invasive breast cancer. This activation is associated with a predominantly Th1 cytokine response, which suggests that conditioning with HER-2/neu peptides may be of value in the development of breast cancer vaccines.  相似文献   
18.
Interactions between the CXCR4 chemokine receptor in breast cancer cells and the ligand CXCL12/SDF-1α are thought to play an important role in breast cancer metastases. In this pilot study, CXCR4 expression along with other biomarkers including HER2-neu and EGFR, were measured in primary tumor samples of patients with operable breast cancer to test whether any of these biomarkers alone and in combination could indicate breast cancer with high likelihood of metastasizing to bone marrow. Cytokeratin (CK) positive cells in bone marrow were identified by flow-cytometry following enrichment with CK 7/8 antibody-coupled magnetic beads. Primary tumors (n = 18) were stained with specific antibodies for CXCR4, HER2-neu, EGFR, and PCNA using an indirect avidin–biotin horseradish peroxidase method. The majority of the patients had T2/T3 tumors (72%), or lymph node involvement (67%) as pathologic characteristics that were more indicative of high-risk breast cancer. High CXCR4 cytoplasmic expression was found in 7 of 18 patients (39%), whereas 6 of 18 patients (33%) were found to have CK positivity in bone marrow. The median number of CK+ cells was 236 (range, 20–847) per 5 × 104 enriched BM cells. The presence of CK+ cells in bone marrow was found to be associated with increased expression of CXCR4 alone or in addition to EGFR and/or HER2-neu expression (P = 0.013, P = 0.005, and P = 0.025, respectively) in primary tumors. Furthermore, three patients with high CK positivity (>236 CK+ per 5 × 104 enriched bone marrow cells) in bone marrow exclusively expressed high levels of CXCR4 with EGFR/HER2-neu (P = 0.001). Our data suggest that high CXCR4 expression in breast cancer may be a potential marker in predicting isolated tumor cells in bone marrow. CXCR4 coexpression with EGFR/HER2-neu might further predict a particular subset of patients with high CK positivity in bone marrow.  相似文献   
19.
Recording the motor output of the central nervous system from the cervical spinal cord was investigated as a method of generating voluntary command signals, potentially to be used in quadriplegic individuals. Corticospinal volleys evoked by motor cortex stimulation were recorded from the spinal cord surface with multicontact electrodes in anesthetized cats. The multicontact recordings were analyzed for their information-carrying capacity as a neural interface. Neural signals resulting from the stimulation of various points in the motor cortex were considered as symbols of an alphabet that were sent through a discrete information channel. The information capacity of this channel at the thermal noise level of the electrode contacts was calculated. The maximum information rate was 1.57 bits in a trial for a 4-symbol alphabet. The background noise that reduces the information rate to 50% of its maximum theoretical value was defined as the half-bitrate-noise-tolerance (HBR-NoiseTol) and used as a measure of symbol distinguishability. The HBR-NoiseTol for all trials on average was 24 +/- 12%, 18 +/- 10%, and 15 +/- 9% for interfaces with 2-, 3-, and 4-symbol alphabets (n = 11 trials). The average peak-to-peak amplitude of the neural volleys was 13.5 +/- 6.7 microV (n = 11). These results suggest that the corticospinal signals can be recorded with spatial selectivity from the spinal cord surface and thus warrant further investigation of their potential use for a spinal cord-computer interface.  相似文献   
20.
Pain during sexual activity and ejaculation are the unspoken long-term complications of groin hernia repair. Laparoscopic surgical techniques are associated with decreased post-operative pain and earlier return to daily activities, but its effect on these complications is unclear. This study aims to investigate the effect of transabdominal preperitoneal repair (TAPP) on de-novo pain during sexual intercourse and ejaculation and to compare with open repair. For this reason, two groups were determined according to the surgical technique: the Lichtenstein repair and the TAPP groups and a questionnaire was sent to the patients a minimum of 6 months following the surgery. A total of 317 patients included, as 115 in TAPP and 202 in Lichtenstein repair group. No significant difference was observed concerning pre-operative pain during sexual activity and ejaculation in both groups (p = .75, p = .56). Following the surgery, the number of patients experiencing painful sexual activity was significantly higher in the Lichtenstein repair group compared to the TAPP group (19.3% vs. 11.3%, respectively, p = .03). The post-operative painful ejaculation rate was also significantly lower for the TAPP group (p = .04). The lower rates of post-operative dysejaculation and pain during sexual activity can be achieved with the advantage of laparoscopic surgery.  相似文献   
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