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排序方式: 共有563条查询结果,搜索用时 62 毫秒
1.
Sundaram Hariharan Eric P. Cohen Brahm Vasudev Rimas Orentas Raphael P. Viscidi Justin Kakela Brian DuChateau 《American journal of transplantation》2005,5(11):2719-2724
We evaluated twenty renal transplant subjects at various stages of BKV nephritis (BKVN) for BKV-specific IgG and IgM antibodies using ELISA technique and BKV-DNA using PCR. They were divided as early onset (n = 7), stabilizing (n = 3), resolved (n = 8) and late onset (n = 2) BKVN. BKV-specific antibodies and BKV-DNA were simultaneously determined. The mean BKV-specific IgG level in early onset and stabilizing BKVN were 64 and 39 EIA units, and were significantly lower than 138 EIA units seen in resolved BKVN, P = 0.007, P = 0.008. The mean BKV-specific IgM levels in stabilizing BKVN was higher than resolved BKVN (130 vs 51 EIA units), P = 0.006. Mean plasma BKV loads for each group were 955,925, 5642 and 42 copies/mL of plasma, respectively. Prospective study in six BKVN cases revealed mean IgG, IgM levels and BKV-DNA at the time of diagnosis of BKVN as 39, 110 EIA units and 586,758 copies/mL of plasma, respectively. After a mean period of 5.2 months, IgG level increased to 120 EIA units (p = 0.0058) and had no detectable viral copies in circulation. Recovery from BKVN and elimination of BKV is associated with the development of BKV-specific IgG antibodies and this provides insight into the role of humoral immunity to BKV in the pathogenesis of BKVN. 相似文献
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Repair of large midline incisional hernias with polypropylene mesh: Comparison of three operative techniques 总被引:9,自引:0,他引:9
de Vries Reilingh TS van Geldere D Langenhorst BLAM de Jong D van der Wilt GJ van Goor H Bleichrodt RP 《Hernia》2004,8(1):56-59
Polypropylene mesh is widely used for the reconstruction of incisional hernias that cannot be closed primarily. Several techniques have been advocated to implant the mesh. The objective of this study was to evaluate, retrospectively, early and late results of three different techniques, onlay, inlay, and underlay. The records of 53 consecutive patients with a large midline incisional hernia — 25 women and 28 men, mean age 60.4 (range 28–94) — were reviewed. Polypropylene mesh was implanted using the onlay technique in 13 patients, inlay in 23 patients, and underlay in 17 patients. Either the greater omentum or a polyglactin mesh was interponated between the mesh and the viscera. The records of these 53 patients were reviewed with respect to: size and cause of the hernia, pre- and postoperative mortality and morbidity, with special attention to wound complications. Patients were invited to attend the outpatient clinic at least 12 months after implantation of the mesh for physical examination of the abdominal wall. Postoperative complications occurred in 14 (26.4%) patients. The onlay technique had significantly more complications, as compared to both other techniques. Reherniation occurred in 15 (28.3%) patients. The reherniation rate of the inlay technique was significantly higher than after the underlay technique (44% vs 12%, P=0.03) and tended to be higher than the onlay technique (44% vs 23%, P=0.22). Repair of large midline incisional hernias with the use of a polypropylene mesh carries a high risk of complications and has a high reherniation rate. The underlay technique seems to be the better technique. 相似文献
4.
Nonheme iron in sickle erythrocyte membranes: association with phospholipids and potential role in lipid peroxidation 总被引:5,自引:0,他引:5
Previous studies documented the abnormal association of heme and heme proteins with the sickle RBC membrane. We have now examined RBC ghosts and inside-out membranes (IOM) for the presence of nonheme iron as detected by its formation of a colored complex with ferrozine. Sickle ghosts have 33.8 +/- 18.2 nmol nonheme iron/mg membrane protein, and sickle IOM have 4.3 +/- 3.0 nmol/mg. In contrast, normal RBC ghosts and IOM have no detectable nonheme iron. The combination of heme and nonheme iron in sickle IOM averages nine times the amount of membrane- associated iron in normal IOM. Kinetics of the ferrozine reaction show that some of this nonheme iron on IOM reacts slowly and is probably in the form of ferritin, but most (72% +/- 18%) reacts rapidly and is in the form of some other biologic chelate. The latter iron compartment is removed by deferoxamine and by treatment of IOM with phospholipase D, which suggests that it represents an abnormal association of iron with polar head groups of aminophospholipids. The biologic feasibility of such a chelate was demonstrated by using an admixture of iron with model liposomes. Even in the presence of tenfold excess adenosine diphosphate, iron partitions readily into phosphatidylserine liposomes; there is no detectable association with phosphatidylcholine liposomes. To examine the bioavailability of membrane iron, we admixed membranes and t-butylhydroperoxide and found that sickle membranes show a tenfold greater peroxidation response than do normal membranes. This is not due simply to a deficiency of vitamin E, and this is profoundly inhibited by deferoxamine. Thus, while thiol oxidation in sickle membranes previously was shown to correlate with heme iron, the present data suggest that lipid peroxidation is related to nonheme iron. In control studies, we did not find this pathologic association of nonferritin, nonheme iron with IOM prepared from sickle trait, high-reticulocyte, postsplenectomy, or iron-overloaded individuals. These data provide additional support for the concept that iron decompartmentalization is a characteristic of sickle RBCs. 相似文献
5.
C A Gaydos L Bobo L Welsh E W Hook R Viscidi T C Quinn 《Sexually transmitted diseases》1992,19(6):303-308
A portion of the major outer membrane protein (MOMP) gene from 15 Chlamydia trachomatis serovars was amplified by polymerase chain reaction (PCR) and the product was analyzed by restriction fragment length polymorphism (RFLP). A set of primers was used to amplify an 871 base pair gene fragment encompassing the 4 hypervariable regions of MOMP. AluI digestion of the product gave distinctive patterns for the 15 serovars as demonstrated on silver-stained polyacrylamide gels. A triple digest with EcoRI, HinfI, and HpaII allowed improved discrimination between closely related serovars (C, H, I, J, L3). PCR and RFLP were used to type 50 wild-type clinical isolates and results were compared to results of the solid-phase enzyme immunoassay typing method. These isolates represented the most prevalent genital serovars (D, E, F, K, I and J) in the local sexually transmitted diseases clinic population. For specimens containing 1 serovar, the results of the two methods were similar for 42 samples and discordant for 1 sample. In addition, two samples showed evidence of mixed infection with two serovars as identified by both methods. Five additional specimens contained two serovars, as shown by one or both methods. In all five such specimens, the two typing methods agreed on at least one of the two serovars. For both single and multiple serovar specimens, there was concordance between the two typing methods for 16/17 E serovars, 8/9 D serovars, 8/8 F serovars, 7/7 I serovars, 7/7 J serovars, 5/8 K serovars, and 0/2 G serovars.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
Persistent diarrhea and fecal shedding of retroviral nucleic acids in children infected with human immunodeficiency virus 总被引:3,自引:0,他引:3
Gastrointestinal dysfunction is a serious problem in many children infected with human immunodeficiency virus (HIV), the etiology of which has not been clearly defined. Quantitative nucleic acid amplification was used to study the correlation between shedding of HIV nucleic acids and gastrointestinal symptoms in HIV-infected infants and children. Many with HIV infection and persistent diarrheal disease shed HIV nucleic acids in their feces, as did an HIV-infected patient without apparent diarrheal disease. HIV nucleic acids were not found in feces of non-HIV-infected individuals. Intestinal infection with HIV appears to be important in the pathophysiology of gastrointestinal dysfunction in infants and children with HIV infection. Furthermore, the fecal shedding of HIV may play a role in HIV transmission in environments prone to high levels of fecal-oral contamination. 相似文献
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This study analyses the influence of female and male patient age and human
menopausal gonadotrophin (HMG) requirements on clinical pregnancy rates and
live birth rates with ovulation stimulation using HMG in combination with
intrauterine insemination (IUI). In this study, 363 consecutive HMG/IUI
treatment cycles in 184 patients carried out at a university fertility
centre were analysed in a retrospective fashion. The main outcomes measured
were clinical pregnancy rates and live birth rates. Increased female
partner age (> or = 35) and male partner age (> or = 40) were found
to negatively influence pregnancy rates with HMG/ IUI therapy. In addition,
this study demonstrated a critical threshold of HMG requirements beyond
which pregnancy did not occur. No pregnancies occurred in treatment cycles
requiring > 25 ampoules (1875 IU) of menotrophins to achieve follicular
maturity, irrespective of patient age. In conclusion, female partner age,
male partner age, and HMG requirements all significantly influence
pregnancy rates with HMG/IUI therapy.
相似文献