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Keratography as a guide to selective suture removal for the reduction of astigmatism after penetrating keratoplasty 总被引:2,自引:0,他引:2
After penetrating keratoplasty in 52 eyes, keratography refraction and keratometry were used to select appropriate interrupted sutures for removal in order to reduce astigmatism. All eyes had one continuous and either 12 or 16 interrupted nylon sutures. The keratographs were examined retrospectively and separated into six groups on the basis of similar mire patterns. The removal of single sutures associated with three of these patterns reduced astigmatism by the following average amounts: symmetrical oval pattern, 0.44 diopters (D); D-shaped oval pattern, 2.07 D; and focal indentation pattern, 6.60 D. The other three patterns--mildly disrupted mires, incomplete mires, and uninterpretable mires--did not allow quantification of results. Examples of these keratographic patterns are presented and recommendations are made for their use in the management of astigmatism following penetrating keratoplasty. 相似文献
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Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
6.
Ruth Tachezy Eva Hamsikova Jaroslav Valvoda Marc Van Ranst Jan Betka Robert D. Burk Vladimir Vonka 《Journal of medical virology》1994,42(1):52-59
Recurrent respiratory papillomatosis (RRP) is the most common benign tumour of the larynx, affecting both children and adults. We present a series of 25 patients, including 10 cases of juvenile multiple, 8 cases of adult solitary, and 7 cases of adult multiple RRP. Biopsy tissue from each patient was screened by Southern blot hybridization and polymerase chain reaction for the presence of human papillomavirus (HPV) DNA. Sera from patients and age- and sex-matched controls were tested for the presence of HPV-specific antibodies using a synthetic pep-tide derived from the minor capsid protein (L2) of HPV 6/11. By Southern blot hybridization and/or polymerase chain reaction, biopsies from all patients were positive for HPV 6/11 DNA. There was no difference in antibody response between cases and controls. Female cases and controls had significantly higher antibody titers than male subjects. A correlation was observed between the HPV-specific antibody level and the number of surgery-necessitating recurrences. © 1994 Wiiey-Liss, Inc. 相似文献
7.
Comparison of the hybrid capture tube test and PCR for detection of human papillomavirus DNA in cervical specimens. 总被引:5,自引:3,他引:5 下载免费PDF全文
J U Cope A Hildesheim M H Schiffman M M Manos A T Lrincz R D Burk A G Glass C Greer J Buckland K Helgesen D R Scott M E Sherman R J Kurman K L Liaw 《Journal of clinical microbiology》1997,35(9):2262-2265
The strong association of human papillomavirus (HPV) and cervical cancer makes it important to study HPV detection methods that may play a role in cervical cancer screening. We compared two DNA methods that are commonly used for HPV research in the United States: the MY09/MY11 L1 consensus primer PCR-based test and the first-generation Hybrid Capture tube method (HCT). Laboratory assays by each method were performed with 596 cervicovaginal specimens collected from participants in a large cohort study conducted in Portland, Oreg. Included were 499 specimens from women whose cytology was normal and 97 specimens from women with squamous intraepithelial lesions (SILs). The overall HPV DNA positivity for known types was 22.5% by PCR compared to 13.6% by HCT. When the analysis was restricted to the 14 HPV types detectable by both methods, the sensitivity of HCT, with PCR used as the standard for HPV status, was higher for specimens from women with concurrent SILs (81.0%) than for specimens from women with normal cytology (46.7%). Among specimens testing positive by both methods, 97.2% of the time the two methods agreed on whether specimens were positive for cancer-associated HPV types. Both of these HPV test methods provide information that supplements the information provided by the Pap smear. The PCR method has higher analytic sensitivity than HCT in detecting HPV, but HCT may be helpful in identifying women with concurrent SILs. 相似文献
8.
The glucocorticoid receptor recognizes a specific nucleotide sequence in hepatitis B virus DNA causing increased activity of the HBV enhancer 总被引:10,自引:0,他引:10
R Tur-Kaspa Y Shaul D D Moore R D Burk S Okret L Poellinger D A Shafritz 《Virology》1988,167(2):630-633
The hepatitis B virus (HBV) genome contains a specific DNA binding site for the glucocorticoid receptor. Using DNase I footprinting, this binding site was localized at HBV map positions 341-370 clockwise from the EcoRI site. The DNA sequence protected in the footprint contains two tandem copies of the GRE core hexanucleotide 5'-TGTTCCT-3'. Deletion analysis and reconstruction experiments in plasmid expression vectors demonstrated that this glucocorticoid receptor binding sequence serves as a signal for augmenting glucocorticoid-dependent activity of the HBV enhancer, which is located approximately 730 nucleotides downstream in the HBV genome. Even though it does not serve as an independent enhancer element, the HBV glucocorticoid receptor domain can therefore be categorized as a functional GRE. 相似文献
9.
Detection of chromosomes and estimation of aneuploidy in human spermatozoa using fluorescence in-situ hybridization 总被引:11,自引:0,他引:11
The development and application of fluorescence in-situ hybridization
(FISH) has opened the way for comprehensive studies on numerical chromosome
abnormalities in human spermatozoa. FISH can be rapidly applied to large
numbers of spermatozoa and thus overcomes the major limitation of
karyotyping spermatozoa after penetration of zona-free hamster oocytes. The
simultaneous hybridization of two or more chromosome-specific probes to
spermatozoa and subsequent detection of the bound probes using different
fluorescent detection systems enables two or more chromosomes to be
localized simultaneously in the same spermatozoon and provides a technique
for undertaking reasonable estimates of aneuploidy. The most commonly used
probes are those which bind to the centromeric region of specific
chromosomes. Most studies to date have concentrated on estimating
aneuploidy in spermatozoa from normospermic men, although reports are
beginning to appear on aneuploidy in spermatozoa from subfertile and
infertile men. Multi- probe FISH studies have generally reported disomy
(hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary
evidence that some chromosomes such as X, Y and 21 are predisposed towards
higher rates of non-disjunction during spermatogenesis. There are also
suggestions of inter-donor variability in aneuploidy frequencies for
specific chromosomes, although this requires confirmation in larger
studies. While FISH is clearly a powerful technique that has many
applications in reproductive medicine, it must also be realized that it
does have limitations and the technology itself is still evolving and has
yet to be fully validated on spermatozoa.
相似文献
10.