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991.
We report a case of embolomycotic aneurysm of the right iliac artery secondary to bacterial endocarditis. The patient, a 33-year-old woman, presented with unilateral hydronephrosis and lower extremity edema caused by aneurysmal compression of the ipsilateral ureter and the external iliac vein. She was treated with ligation and an extraperitoneal left-external-iliac-artery to right-femoral-artery bypass using a knitted Dacron prosthesis. Since her surgery, our patient has been well except for persistence of moderate leg edema. To the best of our knowledge, we are reporting the 1st case of embolomycotic external-iliac-artery aneurysm secondary to bacterial endocarditis and resulting in hydronephrosis and venous insufficiency.  相似文献   
992.
BALB/c mice sensitized by repeated injections of immature eggs of the trematode worm, Schistosoma japonicum, were challenged with low numbers of cercariae and evidence was sought for inhibition of embryonation by examination of eggs in livers and intestines at days 40 - 42 of infection. In contrast to the situation in unsensitized control mice, a greater proportion of dead eggs was noted in tissues of many of egg-sensitized mice. There was also a decrease in the proportion of mature eggs relative to control mice. A substantial number of egg - sensitized mice contained no eggs in the liver though eggs were readily detected in their intestinal walls. The data support the concept that immune effector mechanisms act on eggs in a manner that prevents their full development into a miracidium and thus a rich source of immunopathologic antigens.  相似文献   
993.
The purpose of this work was to determine the expression of type Th1 cytokines: IL-2 and IFNgamma, and Th2: IL-4 and IL-6, as well as TNF-alpha in patients with precancerous lesions of the uterine cervix and their relationship with the human papiloma virus (HPV). 30 patients with precancerous lesions (NIC 1: 70%, NIC 2: 16.7% and NIC 3: 1.3%) and 9 normal controls were studied. A clinical history, gynecological evaluation, cytology and an uterine biopsy were carried out in each patient and control. PCR was used for the diagnosis of HPV. IFN-gamma expression (positive cells/field) was increased in patients with NIC (5.06 +/- 4.7 vs 0 in the control group; p < 0.05). TNFa was a little higher in pathologycal tissues than in the controls (5.23 +/- 3.63 vs 1.55 +/- 2.65; p < 0.05). IL-2 was higher in pathologycal cases than in the controls (8.73 +/- 5.23 vs 0.33 +/- 1, p < 0.05). IL-4 were expressed in both, patients and controls (6.53 +/- 5.23 vs 5.77 +/- 7.32). IL-6 was also higher in patients (4.63 +/- 3.34 vs 0.77 +/- 2.33; p < 0.05). When the HPV status was considered, only IFN-gamma (p < 0.05) and IL-2 (p < 0.05) were significantly higher in HPV positive patients (n = 4) compared to controls. When HPV+ patients were compared with HPV- patients, only IFNgamma was significant (11.5 +/- 5 vs 4.07 +/- 3.8; p < 0.05). In conclusion, Type Th1 immune response prevails in patients with precancerous lesions, whether they are HPV positive or not.  相似文献   
994.
The Mera Silox-S is a silicone hollow-fibre membrane oxygenator made up of thousands of fibres in a clear polycarbonate housing. Being a silicone membrane it does not have the plasma leakage problem associated with conventional microporous hollow fibres when used in a long-term application. This device (Mera Senko Medical Instrument Co., Japan) is made in three sizes: 0.3, 0.5 and 0.8 m 2. The performance of the 0.5 m 2 and 0.8 m 2 Silox-S membrane oxygenators was tested in vitro using filtered ovine blood and a customized test circuit designed to provide a continuous source of de-oxygenated, CO 2-laden blood, according to the AAMI standard for oxygenator performance. The 0.8 m 2 membrane provided excellent oxygenation, with a transfer rate of 13.0-43.5 ml/min for blood flows of 200-800 ml/min. CO 2 transfer over the same range of flows measured 32.3-40.8 ml/min. Flow rates of 100-500 ml/min for the 0.5 m 2 membrane provided an oxygen transfer of 6.8-28.3 ml/min and would probably not be suited for the existing neonatal ECMO population. A matter of concern with both oxygenators was an increased pressure drop for blood flow through the devices. The delta P for the 0.5 m 2 for flows of 100-500 ml/min ranged from 155 +/- 7 mmHg to 516 +/- 6 mmHg. For the 0.8 m 2, delta P was 194 +/- 39 mmHg to 492 +/- 53 mmHg for flows of 200-800 ml/min. Overall, favourable results support further long-term evaluation for potential use in neonatal ECMO.  相似文献   
995.
This study estimated the prevalence of violations of the International Code of Marketing of Breast‐milk Substitutes (BMS) and subsequent resolutions of the World Health Assembly (Code) at health facilities, points of sale (POS), and on BMS labelling and media in Mexico. We carried out a cross‐sectional survey among 693 mothers with children aged less than 24 months and 48 health providers at public and private health facilities in two states of Mexico. Observational assessment at 20 POS and the health facilities was conducted as well as an analysis of labels on BMS products for sale. Women attending public and private health facilities reported receiving free BMS samples in the previous 6 months (11.1%), and about 80% reported seeing BMS promotion in the mass media. Health providers reported contact with BMS manufacturer representatives in the previous 6 months (15.5%), and only 41.6% of the health providers had knowledge of the Code. BMS promotions were identified at nearly all POS. Analysis of 190 BMS labels showed that 30% included pictures/text idealizing the use of BMS, and all labels incorporated health and nutrition claims. Violations of the Code are prevalent within the health services, POS, and labelling of BMS products. The high percentage of health providers with no knowledge of the Code calls for action at national level to better disseminate and comply with the Code. A transparent, free from commercial influence, and continual monitoring system for Code compliance is needed, including a follow‐up component on sanctions for contraventions of the Code.  相似文献   
996.
997.
Here, we report a patient with ring chromosome 6 [r(6)], associated with anterior segment dysgenesis (ASD) and other anomalies. The phenotype was due to a 1880 kb microdeletion at 6p25.3 identified by whole‐genome array analysis, and was mainly attributable to a FOXC1 haploinsufficiency. Currently 37 patients with r(6) have been reported. We found that facial dysmorphism, ASD, heart anomalies, brain anomalies, and hearing loss are constant features only in severe cases of r(6), mainly related to hemizygosity of FOXC1. Thus, overlaps with other FOXC1 related phenotypes, such as the 6p25 deletion syndrome, Axenfeld‐Rieger syndrome type 3, and ASD type 3. Contrarily, those patients whose r(6) does not disrupt FOXC1, have mild or moderate phenotypes and do not exhibit ASD.  相似文献   
998.
999.
1000.
Interferon beta induces T-helper 2 immune deviation in MS   总被引:6,自引:0,他引:6  
Kozovska ME  Hong J  Zang YC  Li S  Rivera VM  Killian JM  Zhang JZ 《Neurology》1999,53(8):1692-1697
OBJECTIVE: To define the in vitro effects of interferon beta la (IFN-beta1a) on myelin basic protein (MBP)-reactive T cells and to determine its regulatory mechanism on cytokine networks in patients with MS. METHODS: The proliferation and cytokine production of MBP-reactive T-cell clones were measured in thymidine uptake assays and ELISA respectively. The precursor frequency of MBP-reactive T cells was estimated in a microwell culture system. RESULTS: IFN-beta inhibited the proliferation of established MBP-reactive T-cell clones, which correlated with enhanced production of anti-inflammatory interleukin (IL)-4 and IL-10, and a decrease in tumor necrosis factor alpha (TNF-alpha) and IFN-gamma. When examined with peripheral blood mononuclear cells (PBMCs), IFN-beta was found to reduce the in vitro T-cell responses to MBP, as indicated by the significantly decreased frequency of MBP-reactive T cells. The decreased frequency of MBP-reactive T cells corresponded to an augmented production of IL-4 and IL-10. Although the level of TNF-alpha and IFN-gamma was generally unaltered or decreased, IFN-beta appeared to enhance the production of IFN-gamma in PBMCs derived from some individuals with MS. CONCLUSION: Interferon beta la (IFN-beta) suppresses myelin basic protein (MBP)-reactive T cells and induces immune deviation toward the production of T-helper 2 cytokines, which may contribute to its therapeutic benefit in MS. The study also suggests some heterogeneity in MBP-reactive T-cell responses to IFN-beta in different individuals with MS.  相似文献   
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