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1.
We report the case of a 3-year-old girl with temporomandibular ankylosis, which was treated with a costochondral graft and required two further resections because the grafted tissue had overgrown.  相似文献   
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p53 codon 72 polymorphism and risk of cervical carcinoma in Korean women   总被引:3,自引:0,他引:3  
A common polymorphism of the wild type p53 is known at codon 72 of exon 4, with 2 alleles encoding either arginine (CGC, p53Arg) or proline (CCC, p53Pro). A recent study suggested that this polymorphism affects the susceptibility of p53 protein to human papillomavirus E6 oncoprotein mediated degradation and that individuals homozygous for p53Arg are seven times more susceptible to HPV-associated carcinogenesis of the cervix than heterozygotes. To examine whether the p53Arg genotype could be a risk factor for HPV-associated cervical carcinomas in the Korean population, we analyzed the p53 codon 72 polymorphism status of HPV-positive invasive cervical carcinomas from 52 Korean women and 103 healthy control samples. The proportion of individuals homozygous for p53Arg, homozygous for p53Pro, and heterozygous for the two alleles were 40%, 19%, and 41% in normal healthy controls; 42%, 17%, and 40% in women with HPV-positive invasive cervical carcinoma. There were no significant differences in the distribution of p53 genotypes between controls and cervical carcinomas. This finding indicates that the p53Arg genotype is not associated with an increased susceptibility to cervical carcinoma in Korean women.  相似文献   
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The hypo-osmotic swelling test (HOST or HOS test) usually takes into consideration the total HOS response value with no emphasis either on the value of the response subtypes or the response evaluation time. This study investigated the time course of HOS responses and analysed their physiological relevance. Raw semen spermatozoa and Percoll washed spermatozoa were used in the experiment. The morphological changes in the sperm tail were monitored by incubating the spermatozoa in the hypo- osmotic solution for 16 different time periods. The HOS reactive spermatozoa and the type of HOS reaction (swelling subtypes) of the samples subjected to different duration of treatment were identified under a phase contrast microscope. Also the fate of individual spermatozoa in a hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed to a hypo-osmotic solution, the motility lasted usually less than 2 min and motility characteristics were uniquely different from that of the spermatozoa under iso-osmotic conditions. The HOS response development was permanent but the motility loss due to hypo-osmotic shock was reversible up to 1 min of incubation. There was an indication of ordered transition among the HOS swelling subtypes apparently initiating with subtype b destined to c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and increase, respectively, while subtype b showed abrupt initial increase and then gradual decrease. Transition from b to g could be direct or via one or more than one subtypes. Ultrastructure based analysis indicated that HOS response subtypes are the apparent reflection of the differences in the cytoskeletal assembly of the sperm tail and thus may be identifying different physiological variants in the sperm population. These results indicate that shorter incubation is essential to document the kinetics of various HOS responses but the conventional HOS test misses these important HOS features because of lengthy incubation. Since the time course of ordered transition of HOS responses will vary more than the total HOS response in semen of different aetiologies, the importance of HOS response subtypes and response evaluation time should be taken into consideration when applying HOS test.   相似文献   
6.
Applications of the pulsatile flow versatile ECLS: in vivo studies   总被引:3,自引:0,他引:3  
INTRODUCTION: T-PLS (Twin-Pulse Life Support) is the first commercial pulsatile ECLS (Extra Corporeal Life Support) device (1). The dual sac structure of T-PLS can effectively reduce high membrane oxygenator inlet pressure and hemolysis. To verify both the use of T-PLS for ECLS and the advantages of T-PLS, we tested various models. METHOD AND RESULTS: In the partial CPB (cardio pulmonary bypass) model (swine), T-PLS (N = 6), and Biopump (N = 2), a single pulsatile pump (N = 2), were compared. In the case of single pulsatile flow, during pump systole, pressure increased to 700 - 800 mmHg at the inlet port of the membrane oxygenator. fHb, a hemolysis measurement value, was about 80 mg/dL at 3 hours. On the contrary, because of T-PLS's dual sac system, the pressure of T-PLS had a maximum value of about 250 mmHg and fHb was similar to that of the commercial centrifugal pumps. In the total CPB model (bovine, N = 6), the heart was stopped via cardioplegia (Kcl). T-PLS flow was maintained at 3.0-4.5 L/min. T-PLS functioned like a natural heart, having a pulse pressure of 26-43 mmHg and a pulse rate of 40-60 bpm (beats per minute). In the emergency case model (canine, N = 6), T-PLS was started 10 minutes after cardiac arrest from electronic shock. In spite of cardiac arrest for a period of 40 minutes, the heart was recovered after defibrillation. In the ARDS (Acute Respiratory Distress Syndrome) model (canine, N = 6), minimal ventilator parameters were set: tidal volume 130 ml, respiration rate = bpm, FiO2 = 10%. Three hours after starting T-PLS, PO2 of the carotid artery blood (after 2 hours: 195 +/- 89.4; after 3 hours: 258 +/- 99.3 mmHg) was above half the value of the femoral artery but was within normal range. CONCLUSION: It is suggested that a portable pulsatile ECLS like T-PLS may be used as a CPB device and as an alternative CPR (cardiopulmonary resuscitation) device in the case of cardiac arrest. Due to the pulsatile flow, oxygenated blood is delivered to the patient without overloading the ARDS patients heart.  相似文献   
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The coagulation of Limulus amebocyte lysate (LAL) can be activated through two pathways, one initiated by endotoxin and the other by beta-glucans. The two pathways join at the step of activation of the proclotting enzyme. We report here that the endotoxin-activated pathway can be differentially inhibited by two methods in a Limulus enzyme-linked immunosorbent assay (ELISA), either by the combined use of dimethyl sulfoxide and polymyxin B or by a monoclonal antibody against Limulus factor C. LAL reactivities to 10 different endotoxin preparations could be inhibited by the former method by a factor of 10(4) to 10(6) and could be blocked almost totally by the latter method, irrespective of the source of endotoxin. The sensitivity of the assay was approximately 50 pg/ml both for curdlan from Alcaligenes faecalis and for laminarin from Laminaria digitata. We also found that the beta-glucan-activated pathway could be totally blocked by laminarin (> 1 microgram/ml) without affecting the endotoxin-activated pathway, allowing endotoxin to be quantitated specifically by the Limulus ELISA with a detection limit of 0.005 endotoxin unit per ml. The use of uninhibited and differentially inhibited ELISAs demonstrated that different LAL preparations showed much greater variation in assaying beta-glucans than in assaying endotoxins. The LAL reactivity of normal human plasma was found to be due to the activation of the beta-glucan pathway, but not the endotoxin pathway, of LAL.  相似文献   
8.
There is persuasive epidemiological and experimental evidence that dietary polyphenols have anti-inflammatory activity. Aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) have long been used to combat inflammation. Recently, cyclooxygenase (COX) inhibitors have been developed and recommended for treatment of rheumatoid arthritis (RA) and osteoarthritis (OA). However, two COX inhibitors have been withdrawn from the market due to unexpected side effects. Because conventional therapeutic and surgical approaches have not been able to fully control the incidence and outcome of many inflammatory diseases, there is an urgent need to find safer compounds and to develop mechanism-based approaches for the management of these diseases. Polyphenols are found in many dietary plant products, including fruits, vegetables, beverages, herbs, and spices. Several of these compounds have been found to inhibit the inflammation process as well as tumorigenesis in experimental animals; they can also exhibit potent biological properties. In addition, epidemiological studies have indicated that populations who consume foods rich in specific polyphenols have lower incidences of inflammatory disease. This paper provides an overview of the research approaches that can be used to unravel the biology and health effects of polyphenols. Polyphenols have diverse biological effects, however, this review will focus on some of the pivotal molecular targets that directly affect the inflammation process.  相似文献   
9.
To study the active proteins which participate in the reaction of Limulus amoebocyte lysate (LAL) with lipopolysaccharide, antibody was raised in rabbits against LAL. When LAL was run against rabbit antiserum in crossed immunoelectrophoresis, a complex precipitin pattern appeared. Profound changes took place after reaction of LAL with lipopolysaccharide. The most distinct change was the complete disappearance of the cathodic migrating protein coagulogen, because the antigenicity of coagulogen was lost. Based on this observation, a new rocket immunoelectrophoretic method was developed to detect the disappearance of coagulogen after reaction of LAL with lipopolysaccharide. This assay method was used on clinical specimens (cerebrospinal fluid, plasma, ascites, and urine). It was used as a qualitative test, when a single sample is tested, or as a quantitative assay, when a number of sample dilutions were tested. The new method showed a higher degree of accuracy and sensitivity in comparison with the tube test and it can be used for both research and diagnostic purposes.  相似文献   
10.
Kim KM  Kim HW  Kim JO  Baek KM  Kim JG  Kang CY 《Immunology》2002,107(4):472-479
4-1BB(CD137) is a member of the tumour necrosis factor receptor superfamily and is expressed on activated T cells, monocytes and natural killer (NK) cells. The interaction of 4-1BB and 4-1BB ligand provides a costimulatory signal leading to T-cell activation. The expression of 4-1BB has been known to be activation dependent. Interestingly, we found that expression of 4-1BB increased in human peripheral blood mononuclear cells after exposure to mitomycin C. Thus, we tested whether the treatment with other DNA-damaging agents, such as doxorubicin, bleomycin, and gamma-irradiation, could induce 4-1BB expression. The data indicated that 4-1BB expression increased dose-dependently by these agents reaching maximum at 2-3 days after the exposure. We found that the major 4-1BB-expressing population was CD3+ T cells, although a moderate number of CD14+ cells and a few NKB1+ cells also expressed 4-1BB. The levels of 4-1BB expression induced by anticancer drugs, were relatively lower than that induced by CD3 ligation. Interestingly, at subcytotoxic concentrations, doxorubicin and bleomycin considerably enhanced 4-1BB expression induced by CD3 ligation in CEM cells. The ligation of the damage-induced 4-1BB by monoclonal antibody enhanced the viability and proliferating capacity of the cells. In conclusion, the expression of 4-1BB might be one of the cellular responses of the immune cells against various genotoxic stresses.  相似文献   
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