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1.
A rare case of congenital lumbar hernia associated with carpus equina varus is described in a week old baby. The treatment is described with limited review of the literature.  相似文献   
2.
The effect of tumor necrosis factor (TNF), a potential anti-tumor agent, was assessed both in vivo and in vitro against MBT-2 transitional cell carcinoma of the bladder in C3H/HeHa mice. Systemic administration of either single or multiple doses of TNF into tumor bearing animals resulted in partial tumor regression and had a consistent but transient anti-tumor effect. Compared to control, untreated tumor bearing animals, TNF-treated tumor bearing mice had significantly smaller tumor volumes and slower tumor growth rates over the period of 12 days following TNF inoculation. No significant difference in tumor volumes and tumor growth rates between controls and TNF-inoculated mice was observed from day 12 to day 21 after TNF treatment. Assessment of TNF cytotoxicity against in vitro MBT-2 cell line using 3[H]-thymidine proliferation assay showed significant sensitivity of MBT-2 cells to treatment with TNF. A "Variant" MBT-2 cell line was derived by sequential culturing of the original MBT-2 cells in the presence of progressively higher concentrations of TNF in culture medium. Although the significant growth suppression on the MBT-2 tumor appears to be transient, further studies are warranted which may elucidate the immunologic and biologic behavior of TNF and this transplantable animal tumor.  相似文献   
3.
Background: Tyrosine hydroxylase (TH) is a specific marker for catecholaminergic neurones. Some reports have demonstrated a decrease of TH in the sudden infant death syndrome (SIDS) compared with controls. To further investigate this, the correlation between TH and sleep apnea was investigated here. Materials and methods: Among 27,000 infants studied prospectively to characterize their sleep–wake behavior, 38 infants died under 6 months of age. They included 26 cases of SIDS. All the infants had been recorded during one night in a pediatric sleep laboratory some 3–12 weeks before death. The frequency and the duration of sleep apnea were analyzed. The brain-stem material was collected and subjected to immunohistochemical studies for TH. The density of TH-immunoreactive neurons was measured in the nucleus hypoglossus, nervus vagus dorsalis, solitary and ambiguus and the ventrolateral medulla (VLM) in the medulla oblongata. Correlation analyses were carried out between the density of TH-immunoreactive neurons and the data from the sleep apnea studies. Results: There was no SIDS specific correlation between TH-immunoreactive neurons in the nucleus hypoglossus, nervus vagus dorsalis, solitary and ambiguus and the ventrolateral medulla in the medulla oblongata and the frequency and duration of sleep apnea. Conclusions: No significant association between the pathological data and the physiological data refers to TH-positive neurons in the medulla oblongata in SIDS victims.  相似文献   
4.
Background: The Ki-67 antigen appears in all human proliferating cells during late G1, S, M and G2 phases of the cell cycle, but is consistently absent in the Go phase (noncycling) cells. The correlation between Ki-67 in the brainstem and sleep apnea in victims of the sudden infant death syndrome (SIDS) was investigated to elucidate cell kinetics in the brainstem of this condition, which is still the main cause of postneonatal infant death. Materials and methods: Twenty-six cases of SIDS occurred among 38 infants dying under 6 months of age in a cohort of 27,000 infants studied prospectively to characterize their sleep–wake behavior. All the infants had been recorded during one night in a pediatric sleep laboratory some 3–12 weeks before death. The frequency and duration of sleep apnea were analyzed. At autopsy, brainstem material was collected and immunohistochemistry for Ki-67 was carried out. The density of Ki-67-positive neurons was measured semiquantitatively. Correlation analyses were carried out between the density of Ki-67-positive neurons and the data on sleep apnea. Results: Except in two cases in SIDS victims and in one control, the detection of Ki-67 was negative. No correlation analysis between the Ki-67 and of sleep apnea was found. Conclusions: There were no abnormal cell kinetics detected by the demonstration of Ki-67 antigen in the brainstems of SIDS victims.  相似文献   
5.
6.
PURPOSE: To investigate the relationship between two well-established delayed effects of ionizing radiation, experiments were conducted to determine the induction and expression of lethal mutations (delayed reproductive death) and chromosomal instability with respect to dose and time in a human immortalized keratinocyte cell line. METHODS: HPV-G cells were gamma- or alpha-irradiated and maintained in culture for up to 72 population doublings. At intervals, measurements were made of cloning efficiency and the cells examined for apoptosis and cytogenetic aberrations. RESULTS: The descendants of cells surviving 1 or 3 Gy gamma-irradiation, but not 0.5 Gy gamma-irradiation, exhibited a reduced colony-forming efficiency. The reduction persisted at a constant rate of 15-20% clonogenic cell loss per population doubling for up to 72 population doublings. Apoptosis was demonstrated in all colonies in the 1 and 3 Gy groups at 30 and 72 population doublings post-irradiation but not in the 0.5 Gy group. A significant persistent reduction in colony-forming ability (approximately 80%) was demonstrated in the progeny of cells irradiated with 0.5 Gy alpha-particles. After 30 population doublings, the proportion of chromosomally aberrant cells was significantly greater than control values for all doses of both high- and low-LET radiations. The major cytogenetic aberrations (chromatid breaks, chromosome fragments and minutes) were consistent with the transmission of chromosomal instability. The expression of instability declined between 30 and 72 population doublings in the 0.5 Gy and 3 Gy gamma-irradiation groups, but persisted up to 72 population doublings in the 1 Gy group. The expression of chromosomal instability was greater in the descendants of alpha-irradiated cells and showed little evidence of reduction with time. CONCLUSIONS: Unstable aberrations characteristic of radiation-induced chromosomal instability may commonly result in apoptosis and account for a component of the delayed reproductive death/lethal mutation phenotype in HPV-G cells. However, the absence of lethal mutations in the descendants of 0.5 Gy gamma-irradiated cells indicates a low-LET threshold effect for this particular endpoint. Overall, and particularly at low doses, there is no direct correlation between the two endpoints, indicating the absence of a simple relationship between these manifestations of radiation-induced genomic instability.  相似文献   
7.
EPR技术研究枸杞多糖清除·OH自由基作用   总被引:20,自引:0,他引:20  
目的:探讨枸杞多糖清除自由基的作用.方法:采用电子顺磁共振技术(EPR)检测不同浓度枸杞多糖对·OH自由基的清除作用.结果:枸杞多糖清除·OH自由基的能力在0.25 mg/ml为18.64%,在1.0 mg/ml为87.29%,再增大浓度时清除能力呈下降趋势.结论:枸杞多糖低浓度时具显著清除·OH自由基作用,但高浓度时其清除能力却下降.  相似文献   
8.
The objective of this study was to assess the physico-chemical parameters and waterborne parasites in selected recreational lakes from Malaysia. Samples were collected from seven stations of Recreational Lake A (RL-A) and six stations of Recreational Lake B (RL-B). The samples were processed to detect the presence of Giardia spp. and Cryptosporidium spp. using immunomagnetic separation kit, helminth eggs or ova by bright field microscopy and Acanthamoeba spp. by cultivation in non-nutrient agar. Chemical parameters such as ammonia, chlorine, fluoride, nitrate and nitrite and physical parameters such as dissolved oxygen, electrical conductivity, pH, salinity, temperature and total dissolved solid were also measured. Both lakes were freshwater with salinity ranging from 0.05 to 0.09 ppt. Most stations of these lakes were contaminated with Cryptosporidium spp., Giardia spp., Ascaris spp. and hookworm. Schistosoma spp. was found in RL-B only, while Acanthamoeba spp. was found in all stations. Of all sampling sites, station 5 of RL-B is the most contaminated. Linear regression and correlation analysis revealed that Giardia spp. and Schistosoma spp. showed a significant negative correlation with turbidity (p?<?0.01). Based on the preliminary data obtained, it is clearly shown that there is a necessity to implement the detection of waterborne parasites and physico-chemical analysis in Malaysia. Future work on heavy metals (chromium, copper, mercury and zinc) is recommended to enhance the overall water quality monitoring and to take appropriate safety measures to ensure maintenance of good water standards.  相似文献   
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10.
Although some bariatric guidelines reserve pre-operative trans-abdominal ultrasonography screening for symptomatic patients and those with elevated liver enzymes, there has yet to exist a general consensus regarding this issue. Some centers still employ its use as a vital step in the workup of the bariatric patient. This study aims to observe the prevalent findings on routine pre-operative trans-abdominal ultrasonography when used as a screening tool prior to laparoscopic sleeve gastrectomy (LSG). All patients undergoing LSG were screened pre-operatively with trans-abdominal ultrasonography. A retrospective study was done of the pre-operative ultrasonography results of patients who underwent LSG at Amiri Hospital from 2008 to 2012. A total of 747 patients were included in the study, with a median age of 36 (15–68). Five hundred ninety (79.0 %) patients were females while 157 (21.0 %) were males, with an overall median body mass index (BMI) of 45 (30–90). Two hundred forty patients (32.1 %) had normal pre-operative ultrasonography results, 83 (11.1 %) were found to have gallstones, 427 (57.2 %) had fatty liver, and 55 (7.4 %) had other pathologies. There was no statistically significant association between BMI and gallstones (p?=?0.545) and BMI and fatty liver (p?=?0.418). Trans-abdominal ultrasonography screening prior to LSG revealed a wide range of findings but does not add significant information to the pre-operative workup of patients undergoing the procedure and should be reserved for indicated patients.  相似文献   
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