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1.
When tympanosclerosis involves the tympanic membrane or the lateral ossicles, treatment is usually straightforward and uncomplicated. When the stapes is involved, therapy is more controversial and may be more difficult. We report our results in 154 patients who underwent different surgical procedures for tympanosclerosis of the stapes. Followup was up to 10 years. Pure-tone average threshold was significantly improved (p < 0.05) in patients who underwent mobilization procedures or stapedectomy for definitive treatment. The air-bone gap was less than 20 dB at 6 months postoperative in 72% of patients and less than 30 dB in 90%. At 6 months, 2 years, and 5 years there were no statistically significant differences in hearing results between stapedectomy and mobilization patients, some of whom were followed for up to 10 years. No patient had a profound hearing loss after surgery. Surgical treatment for tympanosclerosis of the stapes is a safe procedure, with hearing results similar to those of surgery for other chronic ear diseases involving the ossicular chain. 相似文献
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MIA SON JEONG‐OK KONG SANG‐BAEK KOH JAEYOUNG KIM MIKKO HÄRMÄ 《Journal of sleep research》2008,17(4):385-394
We investigated the effects of 12‐hour shift work for five to seven consecutive days and overtime on the prevalence of severe sleepiness in the automobile industry in Korea. [Correction added after online publication 28 Nov: Opening sentence of the summary has been rephrased for better clarity.] A total of 288 randomly selected male workers from two automobile factories were selected and investigated using questionnaires and sleep‐wake diaries in South Korea. The prevalence of severe sleepiness at work [i.e. Karolinska Sleepiness Scale (KSS) score of 7 or higher] was modeled using marginal logistic regression and included theoretical risk factors related to working hours and potential confounding factors related to socio‐economic status, work demands, and health behaviors. Factors related to working hours increased the risk for severe sleepiness at the end of the shift in the following order: the night shift [odds ratio (OR): 4.7; 95% confidence interval (CI): 3.6–6.0)], daily overtime (OR: 2.2; 95% CI: 1.7–2.9), weekly overtime (OR: 1.6; 95% CI: 1.0–2.6), and night overtime (OR: 1.6; 95% CI: 0.8–3.0). Long working hours and shift work had a significant interactive effect for severe sleepiness at work. Night shift workers who worked for 12 h or more a day were exposed to a risk of severe sleepiness that was 7.5 times greater than day shift workers who worked less than 11 h. Night shifts and long working hours were the main risk factors for severe sleepiness among automobile factory workers in Korea. Night shifts and long working hours have a high degree of interactive effects resulting in severe sleepiness at work, which highlight the need for immediate measures to address these characteristics among South Korean labor force patterns. 相似文献
4.
Lawrence G. Lum Edith Burns Marleen M. Janson Paul J. Martin Bernadette R. Giddings Margaret C. Seigneuret Jan E. Noges Sandra C. Galoforo 《Journal of clinical immunology》1990,10(5):255-264
This investigation uses a system for inducing and detecting anti-tetanus toxoid antibody (anti-TT) synthesis to study specific antibody (Ab) synthesis by bone marrow mononuclear cells (MC). We measured the amounts of anti-TT secreted and the number of B cells secreting antibody (Ab). The ELISA plaque detects single B cells secreting specific Ab. The results show that (1) spontaneous anti-TT secretion by MC is higher than spontaneous anti-TT secretion by peripheral blood lymphocytes (PBL) using an ELISA plaque (P<0.01); (2) spontaneous anti-TT production by MC correlated with the serum anti-TT titers as measured by an ELISA (r=0.75,P=0.005); (3) two types of marrow B cells were identified—one that spontaneously secretes anti-TT and another that produces anti-TT after TT-stimulation; (4) the frequency of anti-TT-secreting B cells is higher in MC than in PBL; (5) the amount of Ab secreted per marrow B cell is not different from that secreted by a peripheral B cell; and (6) marrow B cells could be induced to produce anti-TTin vitro up to 10 months without added cytokines. These results show that bone marrow is a major repository for differentiated B cells that spontaneously produce Abs to maintain circulating Abs titers and for memory B cells that can be induced to produce specific Ab. 相似文献
5.
Laboratory support in the diagnosis of coagulation disorders 总被引:1,自引:0,他引:1
In spite of recent advances in knowledge concerning the detailed biochemistry of blood coagulation, the diagnosis of haemostatic disturbances remains an important problem of clinical judgement in many instances. Laboratory support relies initially on a series of screening tests designed to investigate the general nature of blood clotting. Recent interest in these aspects is centred on standardization and quality assurance of methods and results. Procedures have been recommended in an attempt to unify data. Several aspects of conventional laboratory investigations have been modified and the reliability of diagnostic information has been improved. Some relatively recent findings have extended the application to coagulation studies. For example, the discovery of protein C, a potent physiological inhibitor of blood coagulation, has clarified the nature of the clotting disorder in some patients with hereditary thrombosis disease. In addition, close analysis of plasma from patients with systemic lupus erythematosus has stimulated interest in the association between the haemostatic, neurological and immunological abnormalities recorded in these patients. More recently, sophisticated techniques for the diagnosis of many coagulation factor defects have been developed. Carrier detection of the sex-linked disorders is undertaken widely with reasonable success and reliable prenatal diagnosis procedures have been established in specialized centres. Unequivocal information regarding the diagnosis of carrier status in some families is obtained by the use of gene analysis and linked polymorphisms. Precise details of the genes for several clotting factors have been recorded. Future development in this field is likely to improve the clinical course of many coagulation disorders. 相似文献
6.
Damario MA; Barmat L; Liu HC; Davis OK; Rosenwaks Z 《Human reproduction (Oxford, England)》1997,12(11):2359-2365
Certain patients have a tendency for high response to gonadotrophin therapy
which is often not ameliorated with prior gonadotrophin- releasing hormone
agonist (GnRHa) suppression. As a result, these patients are frequently
cancelled and often experience ovarian hyperstimulation syndrome (OHSS)
episodes during in-vitro fertilization (IVF)-embryo transfer cycles.
Patients with polycystic ovarian syndrome (PCOS) have been noted to be
particularly sensitive to exogenous gonadotrophin therapy. We have
developed a protocol which is effective in improving IVF outcome in high
responder patients, including those with PCOS. Oral contraceptive pills
(OCP) are taken for 25 days followed by s.c. leuprolide acetate, 1 mg/day,
which is overlapped with the final 5 days of oral contraceptive
administration. Low-dose gonadotrophin stimulation is then initiated on the
third day of withdrawal bleeding in the form of either human menopausal
gonadotrophins or purified urinary follicle-stimulating hormone at a dosage
of 150 IU/day. Over a 5 year period, we reviewed our experience utilizing
this dual method of suppression in 99 cycles obtained in 73 high responder
patients. There were only 13 cancellations prior to embryo transfer
(13.1%). The clinical and ongoing pregnancy rates per initiated cycle were
46.5 and 40.4% respectively. Only eight patients experienced mild-moderate
OHSS following treatment. For those patients who had undergone previous
IVF-embryo transfer cycles at our centre, significant improvements were
noted in oocyte fertilization rates, embryo implantation rates and
clinical/ongoing pregnancy rates with this protocol. Hormonal analyses
revealed that the chief mechanism may be through an improved luteinizing
hormone/follicle-stimulating hormone ratio following dual suppression. An
additional feature of this dual method of suppression is significantly
lower serum androgen concentrations, particularly dehydroepiandrosterone
sulphate.
相似文献
7.
Corteling RL Li S Giddings J Westwick J Poll C Hall IP 《American journal of respiratory cell and molecular biology》2004,30(2):145-154
Elevation of the intracellular free Ca(2+) concentration regulates many functional responses in airway smooth muscle, including contraction, proliferation, adhesion, and cell survival. This increase in calcium can be achieved by a release from internal stores (sarcoplasmic reticulum) and/or entry across the cell membrane from the extracellular environment. The molecular identity of this calcium influx pathway in human airway smooth muscle (HASM) remains unclear. Functional studies using Fluo 4-loaded HASM suggest the presence of a histamine H(1) receptor-activated Ca(2+) entry pathway with characteristics similar to those seen with transient receptor potential (TRP) family homologs. Using a range of molecular and cell biological approaches we defined the expression pattern of transient receptor potential classics (TRPC) homologs in airway cells and tissue. Here we show that HASM and human bronchial epithelial cells both express TRPC1, -4, and -6, with HASM also expressing TRPC3 at the mRNA level. Identification of TRPC6 protein by western blot and confocal microscopy indicated that the protein is localized in specific cell types, suggesting that it plays an important role in regulating key functions in airway cells. These data demonstrate the expression of a range of TRPC homologs in the airway and the presence of a functional Ca(2+) entry pathway with characteristics typical of TRPC family members. TRPC homologs may provide an important novel target for the treatment of airway disease. 相似文献
8.
C R Yonker K D Caldwell J C Giddings J L Van Etten 《Journal of virological methods》1985,11(2):145-160
A virus (PBCV) from the symbiotic Chlorella-like algae of Paramecium bursaria has been characterized by sedimentation field flow fractionation (SdFFF). The method yields effective molecular weight M' (molecular weight X buoyancy factor) with a precision of better than 5% under a variety of experimental conditions. The value for M' is used to calculate true molecular weight values through combination with density values; densities were obtained from outside sources, from ultrasonic densitometry, and from sedimentation coefficients determined independently. The actual molecular weight is also determined through SdFFF analysis of the virus in carriers of different densities. Values for the particle diameter are obtained from SdFFF zone broadening studies. The various SdFFF characterization results are compared with molecular weight, particle size, and density values determined by conventional methods. 相似文献
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10.
A school-based study was implemented to assess the family history of coronary heart disease (CHD) and hyperlipidemia (HL) in relation to serum lipoprotein and apolipoprotein levels. One hundred and twenty-five elementary school students (aged9–10 years) and 297 junior high school students (aged12–13 years) participated. Family history was evaluated by the following scoring method: positive family history in a parent. 2 points: in a grandparent. 1 point: and onset of CHD before age 60, 1 additional point. Family history of HL was positive in 8.2% of elementary school students, and 4.2% in junior high school students. Family history of CHD was positive in 11.5% of elementary students, and 11.0% in junior students. Family history score (FHS) for HL was related to serum total cholesterol (TC), low density lipoprotein cholesterol (LDLC), high density lipoprotein cholesterol, apolipoprotein A-T, apolipoprotein B (apoB) and lipoprotein (a) in elementary students, and to TC, LDLC, triglyceride and apoB in junior students. There was no relationship between FHS for CHD and serum lipoprotein or apolipoprotein levels in any student. The children with a positive FH of HL already demonstrated an atherogenic lipid profile while those with FH of CHD did not. which was probably because lipid profiles in children are more genetically mediated by a FH of HL than of CHD. 相似文献