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61.
男性不育症精浆中超氧化物歧化酶、锌、睾酮含量的研究   总被引:2,自引:0,他引:2  
本文采用一种简便灵敏的改良邻苯三酚法测定了236例不育症患者和27例正常育龄男子精浆中铜锌超氧化物歧化酶(CuZn-SoD)含量,同时还测定了精浆锌(Zn)和睾酮(T)含量。结果表明:在不育症精浆中,CuZn-SOD、Zn、T与精子密度之间均有显著正相关(P<0.01);CuZn-SOD和Zn含量与精子活动度均有密切关系,含量高活动度也高(P<0.001);CuZn-SOD和Zn之间亦存在显著正相关(P<0.01). 在精子密度范围同60~100×10~6/ml时.不育组与生育组精浆中CuZn-SOD、Zn、T含量均无统计学差异(P<0.2).本究究提示.CuZn-SOD作为精浆保护因子,通过抑制类脂过氧化反应使精子免受损伤。精浆CuZn-SOD含量测定有可能作为衡量精液质量的新指标。应用SOD类制剂治疗男性不育症可能有裨益。  相似文献   
62.
63.
BACKGROUND: Government policy advocates maternal choice in pregnancy care. Two key issues are place of birth and type of lead professional. Anecdotal evidence suggests there is variation in both these issues across the UK, but there has been no recent national assessment of whether maternal options are in line with government policy. AIM: To establish the range of women's childbirth delivery options, degree of midwife autonomy, and supporting training and governance mechanisms. DESIGN: Two postal questionnaires. SETTING: UK maternity units. METHOD: Questionnaires were sent to maternity services managers. MAIN OUTCOME MEASURES: number and type of units and births, transfers and care types; midwifery procedures; clinical governance and training activities. RESULTS: Completed questionnaires were received from 301 out of 308 (97.7%) units in 2002 and from 258 out of 309 (83.5%) units in 2001. Midwife-led care is available in 186 English (76.9%), 15 Welsh (78.9%), 18 Scottish (48.6%) and three Northern Ireland (30.0%) units. There are 73 (24.3%) stand-alone, 22 (7.3%) alongside, 127 (42.2%) integrated and 79 (26.2%) consultant units (for definitions of unit types, see main text), with a median 2215 hospital, 25 home and 210 midwife-led births. The median antenatal and labour transfers from midwife-led units are 25.5% (interquartile range [IQR] = 18.5-36.5%) and 18.0% (IQR = 13.4-24.8%) respectively; transfers are independent of distance to nearest consultant unit, country and unit type. CONCLUSIONS: Despite government policy promoting greater parental choice, this is not in evidence in many parts of the UK. The wide variations in home birth, midwife-led care and maternity-unit types merit further exploration. If more midwife-led units are to be established as a way of promoting parental choice and dealing with junior doctor rota problems, then such units must have adequate governance and training activities in place.  相似文献   
64.
Sullivan  JL; Woda  BA; Herrod  HG; Koh  G; Rivara  FP; Mulder  C 《Blood》1985,65(5):1097-1104
The virus-associated hemophagocytic syndrome (VAHS) is a disorder characterized by a benign, generalized histiocytic proliferation, with marked hemophagocytosis associated with systemic viral infections. We have studied the virological and immunopathological events occurring in two children experiencing Epstein-Barr VAHS. Neither of the patients had an underlying immunodeficiency and both recovered from their disease and are completely well one year after follow-up. In each patient, evidence for primary Epstein-Barr virus (EBV) infection was documented with a typical humoral immune response, including IgM antibody directed against virus capsid antigen. EBV was demonstrated in lymphoreticular tissues by electron microscopy and molecular hybridization studies. Permissive EBV infection was suggested by the finding of mature virus particles and linear viral DNA in lymphoreticular tissues. Immunopathological studies demonstrated complete effacement of lymph node architecture by a marked proliferation of immunoblasts in patient 1 and infiltration and effacement of the lymph node architecture with benign-appearing histiocytes in patient 2. Atypical lymphocytes characteristic of acute EBV infection were notably absent in the peripheral blood of both patients and cytotoxic T cells, which normally lyse EBV-infected B cells, were also absent from the peripheral circulation. Our observations suggest that EBV-induced VAHS may be the result of an increased virus burden in the face of immunoregulatory cell imbalances.  相似文献   
65.
Urinary excretion of 99mTc administered as microspheres   总被引:1,自引:0,他引:1  
  相似文献   
66.
Agha  FP 《Radiology》1984,153(1):37-42
The changes seen on radiographs of the esophagus following endoscopic injection sclerotherapy (EIS) for varices are described and illustrated. In the early period (within 30 days) after EIS, the spectrum of changes includes mucosal ulceration, luminal narrowing, intramural defects, sinuses, fistulae, esophageal dissection, and perforation. In the late period (after 30 days), the spectrum includes strictures, irregular contour, mural defects, esophageal dysmotility, and luminal obstruction. Familiarity with these radiographic features will aid in proper interpretation of esophagograms following EIS for esophageal varices.  相似文献   
67.
All gallium-67 citrate scans obtained in patients with acquired immunodeficiency syndrome (AIDS) at the Clinical Center, National Institutes of Health (Bethesda, Md.) were retrospectively analyzed and correlated with the results of bronchoscopy, chest radiography, and endoscopy. There were 164 scans of 95 patients. Twenty scans were from patients with Pneumocystis carinii pneumonia; 19 were abnormal, for a sensitivity of 95%. Ga-67 uptake tended to be less in patients receiving therapy for P. carinii pneumonia. Chest radiographs were normal at least initially in three patients with abnormal scans and P. carinii pneumonia. Unusually prominent colonic activity was associated with infection in some patients. No lesions of Kaposi sarcoma showed tracer uptake. Gallium scanning is useful for detecting P. carinii pneumonia and other opportunistic infections in patients with AIDS, but it is not useful for localizing Kaposi sarcoma.  相似文献   
68.
The presence or absence of nine autoantibodies were assessedin 44 patients with ulcerative colitis (17 with hyposplenism)and 22 patients with Crohn's disease (eight with hyposplenism).The purpose of the study was to determine whether hyposplenismin inflammatory bowel disease is associated with an increasedtendency to autoimmunity, or whether autoimmunity is linkednot to hyposplenism itself but to the underlying bowel disease.The results strongly suggest that the latter hypothesis is correct.There was a much higher frequency of autoantibodies in patientswith ulcerative colitis than in those with Crohn's disease (P0.01),suggesting that autoimmune factors are more important in thepathogenesis of ulcerative colitis than in Crohn's disease.  相似文献   
69.
Journal of Neuro-Oncology - Medulloblastoma is the most frequent pediatric malignant brain tumor, and is divided into four main subgroups: WNT, SHH, group 3, and group 4. MYCN amplification is an...  相似文献   
70.

Background

The role of human papillomavirus (HPV) on head and neck squamous cell carcinoma (HNSCC) survival in regions with low HPV prevalence is not yet clear. We evaluated the HPV16 infection on survival of HNSCC Brazilian patient series.

Methods

This cohort comprised 1,093 HNSCC cases recruited from 1998 to 2008 in four Brazilian cities and followed up until June 2009. HPV16 antibodies were analyzed by multiplex Luminex assay. In a subset of 398 fresh frozen or paraffin blocks of HNSCC specimens, we analyzed for HPV16 DNA by L1 generic primer polymerase chain reaction. HNSCC survival according to HPV16 antibodies was evaluated through Kaplan–Meier method and Cox regression.

Results

Prevalence of HPV16 E6 and E6/E7 antibodies was higher in oropharyngeal cancer than in other head and neck tumor sites. HPV16 DNA positive in tumor tissue was also higher in the oropharynx. Seropositivity for HPV16 E6 antibodies was correlated with improved HNSCC survival and oropharyngeal cancer. The presence of HPV16 E6/E7 antibodies was correlated with improved HNSCC survival and oropharyngeal cancer survival. The death risk of oropharyngeal squamous cell carcinoma patients HPV16 E6/E7 antibodies positive was 78 % lower than to those who test negative.

Conclusion

Oropharyngeal squamous cell carcinoma is less aggressive in the HPV16 E6/E7 positive serology patients. HPV16 E6/E7 antibody is a clinically sensible surrogate prognostic marker of oropharyngeal squamous cell carcinoma.  相似文献   
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