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1.
A retrospective review of obstetric records for 1979 in two major Calgary hospitals was undertaken to determine the rate of compliance with postpartum Rh isoimmunization prophylaxis in Alberta. The charts of 4528 women ranging in age from 13 to 46 years were reviewed. The prevalence rate of Rh negativity was found to be 16%. Of the 710 Rh-negative women 490 (69%) were eligible to receive Rh immune globulin (RhIG); that is, they had no anti-D antibodies, and the baby/fetus was Rh-positive or Rh-unknown. RhIG had been administered to 93.6% of the eligible women; the compliance rate ranged from 66.7% for obstetric emergencies (i.e., spontaneous abortion, antepartum or early-pregnancy hemorrhage, or ectopic pregnancy) to 98.2% for postpartum diagnoses. In more than half (54.7%) of the women who underwent amniocentesis Rh type was not determined; the implications of this finding are discussed. Although poor compliance with postpartum RhIG administration is not a reason for withholding antepartum administration of RhIG, maximum compliance with the more cost-effective programs should be attained before antepartum programs are fully implemented. 相似文献
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Affinity labeling of delta-opiate receptors using [D-Ala2,Leu5,Cys6]enkephalin. Covalent attachment via thiol-disulfide exchange 总被引:1,自引:0,他引:1
W D Bowen S B Hellewell M Kelemen R Huey D Stewart 《The Journal of biological chemistry》1987,262(28):13434-13439
[D-Ala2,Leu5,Cys6]Enkephalin (DALCE) is a synthetic enkephalin analog which contains a sulfhydryl group. DALCE binds with high affinity to delta-receptors, with moderate affinity to mu-receptors, and with negligible affinity to kappa-receptors. Pretreatment of rat brain membranes with DALCE resulted in concentration-dependent loss of delta-binding sites. Using 2 nM [3H][D-Pen2,D-Pen5]enkephalin (where Pen represents penicillamine) to label delta-sites, 50% loss of sites occurred at about 3 microM DALCE. Loss of sites was not reversed by subsequent incubation in buffer containing 250 mM NaCl and 100 microM guanyl-5'-yl imidodiphosphate (Gpp(NH)p), conditions which cause dissociation of opiate agonists. By contrast, the enkephalin analogs [D-Ala2,D-Leu5]enkephalin, [D-Ser2,Leu5,Thr6]enkephalin, [D-Pen2,D-Pen5]enkephalin, and [D-Ala2,D-Leu5,Lys6]enkephalin were readily dissociated by NaCl and Gpp(NH)p, producing negligible loss at 3 microM. This suggests that DALCE binds covalently to the receptors. Pretreatment of membranes with the reducing agents dithiothreitol and beta-mercaptoethanol had no effect on opiate binding. Thus, loss of sites required both specific recognition by opiate receptors and a thiol group. The irreversible effect of DALCE was completely selective for delta-receptors. Pretreatment with DALCE had no effect on binding of ligands to mu- or kappa-receptors. The effect of DALCE on delta-binding was: 1) markedly attenuated by inclusion of dithiothreitol in the preincubation buffer, 2) partially reversed by subsequent incubation with dithiothreitol, 3) slightly enhanced when converted to the disulfide-linked dimer, and 4) prevented by blocking the DALCE sulfhydryl group with N-ethylmaleimide or iodoacetamide. These results indicate that DALCE binds covalently to delta-receptors by forming a disulfide bond with a sulfhydryl group in the binding site. The mechanism may involve a thiol-disulfide exchange reaction. 相似文献
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Better procedures for freezing and thawing equine sperm are needed since variable fertility is obtained when cryopreserved sperm are used. To evaluate current methods of freezing equine sperm, we examined spermatozoal quality by means of two new techniques. These measured the integrity of plasma-acrosomal membranes by immunofluorescent analyses of binding of an antibody specific to the acrosome and evaluated eight parameters of spermatozoal motion using a fully automated computerized system. Five ejaculates from each of eight stallions were processed for freezing in egg yolk-lactose extender with 4% glycerol. Spermatozoal quality was assessed at four different points: at less than 15 min after collecting and before processing (Step 1); after centrifugation and just before freezing (Step 2); immediately after thawing less than 3 h after freezing (Step 3); and immediately after thawing 10 to 20 d after freezing (Step 4). Acrosome-specific monoclonal antibody detected differences (P <0.05) among steps and ejaculates within stallions. All parameters of spermatozoal motion, including the percentage of motile sperm, percentage of progressively motile sperm, curvilinear velocity, straight line velocity, linearity, amplitude of lateral head displacement, and radius of the average path for circularly swimming sperm, differed (P <0.05) among steps, and most of these parameters differed among ejaculates within a stallion and among stallions. For Steps 2 and 3, 62 and 37% of the sperm were motile, and 56 and 23% of all motile sperm had a curvilinear velocity of >100 mum/sec. Most damage to sperm occurred as a result of freezing-thawing, whereas centrifugation of sperm caused only minor damage. 相似文献
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Bone morphometrics and tetracycline marking patterns in young growing American alligators (Alligator mississippiensis) 总被引:1,自引:0,他引:1
Nine young American alligators (Alligator mississippiensis) were injected at monthly intervals with tetracycline to determine the bone apposition rate and the resorption patterns over a 3-mo period. The periosteal apposition rate increased progressively over the 3-mo period from 2.99 microns/day to 5.94 microns/day. Endosteal apposition rate was much slower with incomplete tetracycline lines being observed on the endosteum. This suggests that most modeling-resorptive activities occur on the endosteal envelope. 相似文献
8.
Pulse-chase methodology with [35S]methionine as label was employed to determine flow kinetics through the endoplasmic reticulum-Golgi apparatus-(lysosome-) secretory vesicle-plasma membrane export route in livers of animals receiving vitamin A excess by gavage. Overall fraction composition determined by morphometry and by analyses of marker enzymes was unchanged by vitamin administration. The vitamin modified the pattern of flow of proteins through the Golgi apparatus to the cell surface and to lysosomes. Altered flux was evidenced by a markedly reduced rate of labeling of lysosomes and a slightly increased rate of labeling of both total membrane proteins of the plasma membrane and of a specific membrane glycoprotein GP80. Also reduced was overall labeling of the Golgi apparatus. Differences in the rate or routes of trafficking of glycoproteins through the Golgi apparatus together with altered opportunities for processing might account for some of the alterations in glycoconjugate glycosylation associated with excess vitamin A administration. 相似文献
9.
Goats and some sheep synthesize a juvenile hemoglobin, Hb C (alpha 2 beta
C2), at birth and produce this hemoglobin exclusively during severe anemia.
Sheep that synthesize this juvenile hemoglobin are of the A haplotype.
Other sheep, belonging to a separate group, the B haplotype, do not
synthesize hemoglobin C and during anemia continue to produce their adult
hemoglobin. To understand the basis for this difference we have determined
the structural organization of the beta- globin locus of B-type sheep by
constructing and isolating overlapping genomic clones. These clones have
allowed us to establish the linkage map 5' epsilon I-epsilon II-psi beta
I-beta B-epsilon III-epsilon IV- psi beta II-beta F3' in this haplotype.
Thus, B sheep lack four genes, including the BC gene, and have only eight
genes, compared with the 12 found in the goat globin locus. The goat
beta-globin locus is as follows: 5' epsilon I-epsilon II-psi beta X-beta
C-epsilon III-epsilon IV-psi beta Z-beta A-epsilon V-epsilon VI-psi beta
Y-beta F3'. Southern blot analysis of A-type sheep reveals that these
animals have a beta- globin locus similar to that of goat, i.e., 12 globin
genes. Thus, the beta-globin locus of B-haplotype sheep resembles that of
cows and may have retained the duplicated locus of the ancestor of cows and
sheep. Alternatively, the B-sheep locus arrangement may be the result of a
deletion of a four-gene set from the triplicated locus.
相似文献
10.
Identification and characterization of a B cell activation factor (BCAF) produced by a human T cell line 总被引:1,自引:0,他引:1
A human T cell line, Peer, that expresses the T cell helper phenotype produces discrete activation and growth factors for tonsillar B cells. The B cell activation factor produced by Peer is biochemically and physiologically distinct from other lymphokines known to enhance B cell proliferation, namely, interleukin 1, interleukin 2, interferon, and previously characterized B cell growth factors (BCGF). The BCGF produced by Peer is functionally similar to previously described BCGF but has a m.w. of approximately 30,000 daltons. The identification and characterization of a T cell-derived activation factor that can induce apparently resting (Go phase) B cells to enter S phase in the absence of an exogenous first signal has important implications in the additional dissection of the complex steps in the human B cell cycle. 相似文献