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11.
Joseph C. Gretzula D.O. Osmar Hevia B.S. Lawrence S. Shachner M.D. John H. DiLiberti M.D. † R. H. A. Ruvalcaba M.D. ‡ James R. Schimshock M.D. § Richard G. Weleber M.D. Fahed Halal M.D. # Mark H. Lipson M.D. Bruce Blumberg M.D. †† Paul J. Weber M.D. 《Pediatric dermatology》1988,5(1):28-32
In 1980 a syndrome was first described in two adult males, consisting of macrocephaly, pigmented macules on the glans and shaft of the penis, and hamartomatous intestinal polyps. Since then, 10 additional cases have been identified. Herein, we present two new cases and review the cutaneous manifestations as well as additional features in patients with the Ruvalcaba-Myhre-Smith syndrome. 相似文献
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Juliene G. Lipson 《Journal of nursing scholarship》1992,24(4):313-318
Esther Lucile Brown, who died in 1990 at the age of 92, was a social anthropologist at the Russell Sage Foundation for more than 30 years. Among her contributions were ground-breaking studies of the professions and stimulation of the development of medical social science. Her research on nursing stimulated professionalization and nursing education's move into the university. The accuracy of her research findings on nursing and psychosocial aspects of patient care led many to assume that she was a nurse. This memorial focuses on her contributions and personal impact on friends and colleagues. 相似文献
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16.
Isolation of a new clathrin heavy chain gene with muscle-specific expression from the region commonly deleted in velo-cardio-facial syndrome 总被引:3,自引:4,他引:3
Sirotkin H; Morrow B; DasGupta R; Goldberg R; Patanjali SR; Shi G; Cannizzaro L; Shprintzen R; Weissman SM; Kucherlapati R 《Human molecular genetics》1996,5(5):617-624
Velo-cardio-facial syndrome (VCFS) and DiGeorge syndrome (DGS) are
developmental disorders characterized by a spectrum of phenotypes including
velopharyngeal insufficiency, conotruncal heart defects and facial
dysmorphology among others. Eighty to eighty-five percent of VCFS/DGS
patients are hemizygous for a portion of chromosome 22. It is likely that
the genes encoded by this region play a role in the etiology of the
phenotypes associated with the disorders. Using a cDNA selection protocol,
we isolated a novel clathrin heavy chain cDNA (CLTD) from the VCFS/DGS
minimally deleted interval. The cDNA encodes a protein of 1638 amino acids.
CLTD shares significant homology, but is not identical to the ubiquitously
expressed clathrin heavy chain gene. The CLTD gene also shows a unique
pattern of expression, having its maximal level of expression in skeletal
muscle. Velopharyngeal insufficiency and muscle weakness are common
features of VCFS patients. Based on the location and expression pattern of
CLTD, we suggest hemizygosity at this locus may play a role in the etiology
of one of the VCFS-associated phenotypes.
相似文献
17.
Mahadevan MM; McIntosh Q; Miller MM; Breckinridge SM; Maris M; Moutos DM 《Human reproduction (Oxford, England)》1998,13(4):979-982
Cryopreservation of human zygotes and embryos has been routinely performed
by in-vitro fertilization clinics for many years. Karran and Legge (1996)
first reported that formaldehyde (FA) present in the cryoprotective
solutions can have a deleterious effect on mouse oocytes. FA is a
cytotoxic, carcinogenic and mutagenic chemical. The effect of FA on mouse
zygotes was investigated. In addition, the concentrations of FA in
propanediol (PROH) obtained from various sources were determined. Pooled
1-cell embryos were dispensed into droplets of modified Ham's F10 or human
tubal fluid containing various concentrations of FA. Since bovine serum
albumin (BSA) may minimize toxicity additional trials were done as above in
the absence of BSA. FA concentration in the standard 1.5 M PROH, from
different sources in water, was measured in the same assay using a standard
curve of 0-100 microM FA. FA in a complex medium had a significant
deleterious effect on embryo development and hatching but only at 1 mM
concentration (P < 0.000001; see Tables I-III). There was no significant
effect of FA at 100 microM. However, in a simple medium even 50 microM FA
decreased embryo hatching. FA was present in 1.5 M PROH from different
sources (range 1.0-35.3 microM concentration). It appears that FA
concentrations do not increase with storage because FA concentrations were
low even after opening and storage for 3 years on the shelf. This suggests
that FA is a contaminant during the manufacturing process and may vary from
manufacturer to manufacturer and batch to batch. Until further studies are
done to confirm the lack of toxicity to embryos during cryopreservation
(with or without FA scavengers) it may be prudent to screen all batches of
cryoprotectants for FA as part of quality control.
相似文献
18.
Three-generation transmission of Hirschsprung's disease 总被引:1,自引:0,他引:1
19.
Glycoproteins present in human follicular fluid that inhibit the zona- binding capacity of spermatozoa 总被引:1,自引:0,他引:1
Previous studies have suggested that human follicular fluid contains
factors that reduce the zona-binding capacity of spermatozoa. The present
study provides further evidence of the existence of such factors. Using the
hemizona binding assay (HZA), we have shown that the inhibitory effect of
human follicular fluid on the zona-binding capacity of spermatozoa is
concentration-dependent, an inhibitory effect being detected when the
concentration of human follicular fluid was > or = 10%. A 1%
concentration of human follicular fluid did not possess this inhibitory
activity. Heating human follicular fluid at 56 degrees C for 30 min did not
affect its inhibitory properties; treatment with proteinase-K abolished
such inhibition. Human follicular fluid was fractionated sequentially by
concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography
and Superose-12 gel filtration. The zona binding inhibitory activity
resided in the fraction which bound to the lectin and Mono Q column and
contained molecules with native molecular weights of 32 and 192 kDa. Sodium
dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that
the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein
remained as a single molecular species under denaturing conditions. We
conclude that two glycoproteins were responsible for the zona binding
inhibitory activity of human follicular fluid. The physiological role of
these factors remains unclear.
相似文献
20.
Detection of precytopathic effect of enteroviruses in clinical specimens by centrifugation-enhanced antigen detection 总被引:2,自引:0,他引:2 下载免费PDF全文
Rapid enterovirus detection is important for decisions about antibiotic administration and length of hospital stay. The efficacy of rapid antigen detection-cell culture amplification (Ag-CCA) was evaluated with monoclonal antibodies (MAbs) 5-D8/1 (DAKO) and Pan-Enterovirus clone 2E11 (Chemicon) with 10 poliovirus, echovirus, and coxsackievirus type A and B stock isolates and College of American Pathologists check samples. By using Ag-CCA technology, MAb 2E11 was more sensitive than 5-D8/1 at detecting a greater number of stock isolates at or past tube (cytopathic effect [CPE]) culture (TC) end points. The efficacy of Ag-CCA in the clinical setting was subsequently confirmed with 273 consecutively freshly collected nasopharyngeal aspirate or swab specimens, rectal swab, and cerebrospinal fluid specimens during the 1999 enterovirus season. All specimens were tested by Ag-CCA in parallel with rhesus monkey kidney (RhMk), MRC-5, and A549 conventional TCs. Approximately 60% of field specimens were additionally tested with Hep-2 and HNK conventional TCs. Sixty-two percent of the clinical specimens tested were Ag-CCA positive after 48 h. Among 51 isolates, the mean time to CPE or culture confirmation was 5.5 days (range, 2 to 18 days). After 48 h, Ag-CCA achieved sensitivity, specificity, and positive and negative predictive values of 62, 100, 100, and 93%, respectively. During the same period, TC-CPE displayed test parameters of 12, 100, 100, and 85%, respectively. After 5 days, the sensitivity and specificity of Ag-CCA increased to 92 and 98%, respectively. Within the same period, isolation attained sensitivity and specificity of 52 and 100%, respectively. Although Ag-CCA displayed slightly reduced sensitivity and reduced specificity compared with conventional cell culture after 14 days, the markedly superior 48-h enterovirus Ag-CCA detection rate supports incorporation of this assay into the routine clinical setting. 相似文献