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31.
Primary subcutaneous phaeohyphomycosis can rarely be caused by Cladophialophora bantiana, and we present the histologic and culture findings of such a case. A 32-year-old African American woman with systemic lupus erythematosus presented with a 2-year history of multiple, recurrent, tender, and ulcerated skin nodules with purulent drainage on her upper back. Histologic sections of the excision demonstrated features of phaeohyphomycosis. Culture findings were characteristic of C bantiana. Of interest, at age 10 she had sustained traumatic implantation of wood splinters into this area during a tornado, yet clinical symptoms of a subcutaneous infection did not manifest until she developed lupus erythematosus at age 27. Our case highlights the role of trauma and immunosuppression in the pathogenesis of subcutaneous phaeohyphomycosis.  相似文献   
32.
一氧化氮与白细胞精子症不育的关系探讨   总被引:13,自引:1,他引:13  
目的 探讨一氧化氮 (NO)与白细胞精子症不育的关系。方法 参照WHO标准方法 ,进行精液常规分析。采用过氧化物酶染色法检测精液中白细胞密度。用改良的低渗肿胀法检测精子细胞膜的完整性。采用镀铜镉还原荧光法 ,检测精液中NO代谢产物硝酸盐 (NO 3 )。结果 白细胞精子症不育组白细胞的密度为 (1.4 8± 0 .90 )× 10 9/L ,NO水平为 (10 3.5± 2 .0 ) μmol/L ,显著高于正常生育组的(0 .73± 0 .2 8)× 10 9/L和 (41.6± 1.8) μmol/L (P分别为<0 .0 5和 <0 .0 0 1)。精子的活动率、精子速度试验 (SVT)及精子头、尾部膜完整率 ,均明显低于生育组 (P <0 .0 1) ,而精子的死亡率则显著高于生育组 (P <0 .0 1)。结论 NO水平与白细胞密度呈正相关 ;与精子的活动率、SVT及精子头、尾膜的完整率呈负相关。表明当精液中的白细胞增高时 ,可产生过量的NO导致精子中毒受损使精子的受精能力下降  相似文献   
33.
BACKGROUND. Routine, voluntary testing of hospital patients for the human immunodeficiency virus (HIV) has been proposed in order to identify those with early HIV infection in a setting where there is ready access to counseling, appropriate clinical referral, evaluation, and therapy. We studied the pattern of HIV infection among patients in 20 U.S. hospitals, in order to evaluate possible national strategies for the routine, voluntary HIV counseling and testing of hospital patients. METHODS. Blood specimens remaining after clinical use from a systematically selected sample of patients at 20 hospitals in 15 U.S. cities were tested anonymously for antibody to HIV type 1 (HIV-1). Multivariate regression was used to determine which variables best predicted HIV seroprevalence in individual hospitals. Using these data, we estimated the number of HIV-positive patients in all U.S. hospitals and considered the efficiency of routine counseling and testing in different subgroups of patients and hospitals. RESULTS. From September 1989 through October 1991, 9286 of 195,829 specimens (4.7 percent) were positive for HIV-1 in the 20 hospitals. The seroprevalence of HIV at these institutions ranged from 0.2 percent to 14.2 percent. Among HIV-positive patients, 32 percent had symptomatic HIV infection or the acquired immunodeficiency syndrome (AIDS) at the time of admission or evaluation. In the 20 hospitals, HIV seroprevalence was 10.4 times (95 percent confidence interval, 8.8 to 12.0) the AIDS-diagnosis rate (the annual number of patients with new diagnoses of AIDS per 1000 discharges in 1990). In a multivariate model that included 13 hospital-specific variables, only the AIDS-diagnosis rate was associated with the hospital-specific HIV-seroprevalence rate (P less than 0.001). Using these data and the AIDS-diagnosis rates for all U.S. acute care hospitals, we estimated that 225,000 HIV-positive persons were hospitalized (95 percent confidence interval, 190,000 to 260,000) in all 5558 such hospitals in 1990, including 163,000 persons presenting with conditions other than HIV or AIDS (95 percent confidence interval, 130,000 to 196,000). In 1990, in 593 U.S. hospitals with AIDS-diagnosis rates of 1.0 or more per 1000 discharges, HIV testing of patients 15 to 54 years old (3 million patients, or 12.0 percent of all patients in U.S. acute care hospitals) would have identified an estimated 68 percent of all HIV-positive patients (110,000 patients) who were admitted with conditions other than symptomatic HIV infection or AIDS. CONCLUSIONS. We estimate that about 225,000 HIV-positive persons were hospitalized in 1990, of whom only one third were admitted for symptomatic HIV infection or AIDS. Routine, voluntary HIV testing of patients 15 to 54 years old in hospitals with 1 or more patients with newly diagnosed AIDS per 1000 discharges per year could potentially have identified as many as 110,000 patients with HIV infection that was previously unrecognized.  相似文献   
34.
BACKGROUND: Like other herpes viruses, latent Epstein-Barr virus (EBV) infection can be reactivated to lytic replication. Reactivation can be achieved by treatment with various reagents, including tetradecanoyl phorbol acetate (TPA) and Ca2+ ionophores. Relatively little is known about the physiological factors related to reactivation of EBV. Previous studies have demonstrated that G0/G1 cell cycle arrest is associated with EBV activation, and that hypoxic conditions can induce cell cycle arrest. In the present study we investigated the effect of hypoxia on reactivation of EBV. OBJECTIVE AND METHODS: Hypoxic culture conditions were established and the expression of Zta protein and the number of EBV DNA copies were measured in B95-8 cells maintained under these conditions. RESULTS: Hypoxia treatment not only increased the expression of the EBV immediate-early protein Zta (which mediates the switch between the latent and lytic form of infection), but also increased the number of EBV DNA copies in B95-8 cells. CONCLUSIONS: EBV in latent infection can be activated to lytic infection by hypoxia treatment.  相似文献   
35.
Interleukin-24 and its receptors   总被引:5,自引:0,他引:5  
Wang M  Liang P 《Immunology》2005,114(2):166-170
  相似文献   
36.
AIMS: To evaluate the technique of multiple displacement amplification (MDA) for whole genome amplification from small volume blood samples before sequencing in a clinical test to identify haemoglobin gene mutations. METHODS: Phage phi29 DNA polymerase was used to perform MDA, starting with either 1 micro l of blood or 1 ng of previously isolated blood DNA from 23 patients. The amplified products were then evaluated using a clinical test that involves sequencing the haemoglobin genes to detect mutations. The results were compared with the current clinical test method that uses genomic DNA isolated using column based technology. RESULTS: The MDA technique produced large quantities (theoretically approximately 2 mg) of DNA. The amplification procedure was extremely easy and took about four hours (less than one hour of hands on technician time and three hours for amplification). When MDA products were used in the same clinical test protocol as genomic DNA isolated using column technology, there was 100% concordance for detection of a variety of point mutations in the alpha1, alpha2, and beta globin genes. CONCLUSIONS: The MDA technique is useful for overcoming the problem of insufficient genomic DNA in clinical specimens requiring haemoglobin gene sequencing and could be useful for other clinical applications.  相似文献   
37.
A novel series of 5-substituted-3-(1H-pyrrol-2-yl)-2-oxazolidinones 2a-s has been described as pyrrole analogues of toloxatone and befloxatone, two phenyl-oxazolidinones active as anti-MAO agents and used in antidepressant therapy. Tested against MAO-A and MAO-B enzymes, the majority of 2a-s show highly potent inhibitory effect against the A isoform of the enzyme, with Ki values in the range 0.52-0.004 microM, whilst their anti-MAO-B activity is considerably lower (Ki = >100-0.5 microM). Structurally, 2a-s differs for the substituent inserted at the C5 position of the 2-oxazolidinone ring (hydroxymethyl (2a-d), methoxymethyl (2e-h), azidomethyl (2i-l), methylaminomethyl (2m-p), and aminomethyl (2q-s)), and the size of the alkyl chain at the pyrrole N1 position (methyl, ethyl, allyl, or benzyl). As a rule, apart from the C5 substitution, the bulkier is the alkyl group at the pyrrole-N1, the lower is the anti-MAO-A activity of the compounds, being the N1-methyl derivatives 2a, 2e, 2i, and 2q among the most potent (K(iMAO-A) = 0.087-0.004 microM) and A-selective (A-selectivity ratio: >11,111-41) compounds in this series. Exceptions are represented by the N1-benzyl derivative 2d (K(iMAO-A) = 0.009 microM) and the N1-allylpyrrole 2o (K(iMAO-A) = 0.04 microM). In comparison with the reference drugs, these highly active derivatives are more potent than toloxatone, slightly less potent than befloxatone, and several times more A-selective than both the references. Such results indicate that 2a-s may represent a new promising series of antidepressant agents.  相似文献   
38.
目的:探讨血清、尿液β2-微球蛋白(β2-mieroglobulin,β2-m)对毒性弥漫性甲状腺肿(graves diseases,Graves)患者β2-m含量与甲状腺激素的关系,了解其变化情况及临床意义。方法:采用放射免疫分析和化学发光免疫分析测定了82例Graves病初发未治疗组与同一组经治疗的69例缓解组及13例未缓解组。并和40例健康对照组进行血清、尿液β2-m含量与FT3、FL4、TGA、TMA血清检测。结果:初发组与未缓解组β2-m含量与FT3、FT4含量显著高于健康对照组(P〈0.01)。经治疗组β2-m含量与FT3、FT4含量同步缓解而下降至正常,与未治疗组对比(P〈0.01)。对比健康正常组差异无显著性(P〉0.05)。82例Graves病初发组TGA阳性率为48.7%(40/82),TMA阳性率为53.66%(44/82)。未缓解组TGA阳性率为15.38%(2/13),TMA阳性率为23.07%(3/13)。缓解组TGA、TMA仍有13.04%、15.94%阳性。结论:甲状腺疾病患者β2-m含量与甲状腺激素有密切关系,提示β2-m可作为Graves病疗效观察、病情变化及预后判断的一项辅助诊断指标。  相似文献   
39.
Hürthle cell papillary thyroid carcinoma is a variant of papillary thyroid carcinoma (PTC). Its pathologic and clinical significance has not been well documented. The authors studied the relative incidence of Hürthle cell PTC and the relationship of Hürthle cell PTC to other variants of thyroid carcinoma. Three hundred eighty consecutive cases of thyroid carcinoma were reviewed to identify cases with focal or extensive areas of Hürthle cell PTC, classic PTC, Hürthle cell carcinoma (ie, non-Hürthle cell PTC), and follicular carcinoma. In addition, the status of lymphoid infiltrate in the tumor, stromal invasion with desmoplastic reaction, vascular invasion, and distant and lymph node metastasis were noted by microscopic examination, review of clinical charts, or both. A total of 24 (HCs) and 42 PTCs with Hürthle cells were identified. The latter category was divided into pure Hürthle cell PTC or extensive Hürthle cell (HPTC) (28 cases) and PTC or Hürthle cell carcinoma with focal areas of Hürthle cell PTC (14 cases). The Hürthle cell PTC/Hürthle cell carcinoma ratio was lower than that of PTC/follicular carcinoma (39:289) (P = 0.001). Follicular or solid structures were present in all HPTCs. HPTCs were associated with frequent stromal intrathyroid and extrathyroid invasion, but they tended to have a lower rate of lymph node metastasis (8/28) compared with classic PTC with stromal invasion (108:200) (P = 0.12) and a lower rate of distant metastasis (2:28) compared with Hürthle cell carcinoma (15:24) (P = 0.02) or follicular carcinoma (13:39) (P = 0.04). Warthin-like Hürthle cell PTC (10 cases) was associated with extrathyroid invasion in five cases. In Hürthle cell PTC associated with tall cell variant (10 cases), areas of gradual transition between Hürthle cell PTC and tall cell variant were identified. The latter variant showed the highest rate of extrathyroid stromal and vascular invasion with distant metastasis and patient death compared with all Hürthle cell PTCs and classic PTCs. In conclusion, Hürthle cell PTC is frequently associated with tall cell variant. It has a higher potential for extrathyroid invasion than classic PTC and has vascular invasion and distant metastasis characteristics intermediate between those of classic PTC and Hürthle cell carcinoma with or follicular carcinoma. Hürthle cell PTC tends to show a greater likelihood of extrathyroid invasion when associated with Warthin-like features and tall cell variant PTC, and higher vascular invasion and distant metastasis when associated with tall cell variant.  相似文献   
40.
Maternal and Child Health Journal - Many studies correlate lower health literacy with poorer health outcomes and inferior provider-patient communication. Little is known about how impaired health...  相似文献   
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