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11.
Our experiments were designed to determine whether recombinant ribonuclease inhibitor (RNasin) could inhibit angiogenesis and reduce tumor growth in adult mice. We used the Fajardo disc angiogenesis assay as the primary means of measuring new blood vessel growth. This assay measures the penetration of cells into a polyvinyl alcohol sponge with a central core of ELVAX-coated sponge containing test substances. Cell penetration was reduced to 29.3% of control (phosphate-buffered saline; heat-inactivated RNasin) values. Endothelial cell influx was measured by lectin staining and confirmed by culturing cells isolated from sponges by collagenase treatment. RNasin also reduced the augmented reaction evoked by either basic fibroblast growth factor (bFGF) or sodium orthovanadate. To confirm the anti-angiogenic activity of RNasin, Hydron-coated polyvinyl sponges containing bFGF or bFGF plus RNasin were implanted into adult mouse corneas. bFGF induced a strong angiogenic response that was almost completely inhibited by RNasin. RNasin-containing ELVAX-coated sponges implanted subcutaneously underneath an intradermal inoculum of C755 mammary tumor cells caused significant reduction in tumor growth (P < 0.005). The antitumor effect of RNasin correlated with its effect on tumor-induced neovascularization, suggesting that the ability of RNasin to affect tumor growth was due to its ability to inhibit angiogenesis.  相似文献   
12.
The bioavailability of zinc from defatted soy flour, dried chicken meat or mixed (50:50 dry weight basis) soy flour and chicken meat included in egg white-based diets was investigated in rats. Following a 6-d experimental diet (9 ppm Zn) feeding period, marginally zinc-depleted weanling rats were fed a test meal, identical in composition to the experimental diet except that the protein source was labeled either intrinsically or extrinsically with 65Zn. Retention of 65Zn from the chicken test meal was significantly higher than that from the soy test meal. Retention of 65Zn from the mixed soy/chicken test meal was midway between the retention values for either protein alone regardless of which protein source was labeled. Intrinsic and extrinsic labeling techniques resulted in similar assessment of zinc bioavailability. Additionally, the influence of previous dietary protein source on zinc retention from a soy test meal was investigated. Retention of 65Zn from an intrinsically labeled soy test meal was higher in rats adapted to chicken protein than in rats adapted to soy protein. The levels of tibia zinc and tibia 65Zn were associated with whole-body retention of 65Zn.  相似文献   
13.
For the 1983 nesting season, Forster's tern (Sterna forsteri) reproductive success was significantly impaired on organochlorine contaminated Green Bay, Lake Michigan compared to a relatively uncontaminated inland location at Lake Poygan, Wisconsin. Compared with tern eggs from Lake Poygan, eggs from Green Bay had significantly higher median concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), other polychlorinated dibenzo-p-dioxins (PCDDs), total polychlorinated biphenyls (PCBs), total (three congeners) non-ortho, ortho' PCBs, five individual PCB congeners known to induce aryl hydrocarbon hydroxylase (AHH) and several other organochlorine contaminants. Conversions of analytical concentrations of TCDD and PCB congeners based on relative AHH induction potencies allowed for estimation of total 2,3,7,8-TCDD equivalents. Two PCB congeners, 2,3,3,4,4- and 3,3,4,4,5-pentachlorobiphenyl (PeCB) accounted for more than 90% of the median estimated TCDD equivalents at both Green Bay and Lake Poygan. The median estimated TCDD equivalents were almost 11-fold higher in tern eggs from Green Bay than in eggs from Lake Poygan (2175 and 201 pg/g). The hatching success of Green Bay sibling eggs from nests where eggs were collected for contaminant analyses was 75% lower at Green Bay than at Lake Poygan. Hatchability of eggs taken from other nests and artificially incubated was about 50% lower for Green Bay than for Lake Poygan. Among hatchlings from laboratory incubation, those from Green Bay weighed approximately 20% less and had a mean liver weight to body weight ratio 26% greater than those from Lake Poygan. In both field and laboratory, mean minimum incubation periods were significantly longer for eggs from Green Bay compared to Lake Poygan (8.25 and 4.58 days, respectively). Mean minimum incubation time for Green Bay eggs in the field was 4.37 days longer than in the laboratory. Hatchability was greatly improved when Green Bay eggs were incubated by Lake Poygan adults in an egg-exchange experiment, but was sharply decreased in Lake Poygan eggs incubated in Green Bay nests. Nest abandonment and egg disappearance were substantial at Green Bay but nil at Lake Poygan. Thus, not only factors intrinsic to the egg, but also extrinsic factors (parental attentiveness), impaired reproductive outcome at Green Bay. The epidemiological evidence from this study strongly suggested that contaminants were a causal factor. AHH-active PCB congeners (intrinsic effects) and PCBs in general (extrinsic effects) appeared to be the only contaminants at the concentrations measured in eggs, capable of producing the effects that were observed at Green Bay.  相似文献   
14.
15.
In a human in-vitro fertilization (IVF) programme, the effect of co- culture of embryos with human fibroblasts was evaluated with respect to pregnancy rate and embryo development. Patients were included in the study after giving informed written consent. The IVF treatments were randomly assigned by stratification of both age (<36 versus > or =36 years) and previous IVF attempts (yes versus no). After fertilization was established, the zygotes were transferred to a 4-well dish with or without fibroblasts and cultured for 2 days. On the third day after ovum pick-up (OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were scored and a maximum of three embryos was transferred. Supernumerary embryos of good quality were cryopreserved. The design of this study was a group sequential trial with the objective of detecting differences between pregnancy rates following IVF with conventional incubation or incubation in co-culture with fibroblasts. This design included one evaluation at half-way data collection. In the study, 148 patients had an OPU, of whom 77 were allocated to the co-culture group. There was no statistically significant difference in pregnancy rate, cell number and embryo quality between the two groups. The ongoing pregnancy rate per embryo transfer was 27% in co-culture and 30% in the conventional culture group. The implantation rates per transferred embryo were 17 and 18% respectively. Using a multivariate logistic regression model for the probability of ongoing pregnancies, the odds ratio of co-culture, adjusted for age and previous IVF attempts, was not statistically significant. In conclusion, co-culture with human fibroblasts does not contribute to an improvement of embryo quality nor to a higher pregnancy rate after IVF in an unselected group of patients.   相似文献   
16.
Male genital tract obstructions may result from infections, previous inguinal and scrotal surgery (vasectomy) and congenital bilateral absence of the vas deferens (CBAVD). Microsurgery can sometimes be successful in treating the obstruction. In other cases and in cases of failed surgical intervention, the patient can be treated by microsurgical or percutaneous epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI). We present the results of 39 ICSI procedures for obstructive azoospermia in 24 couples. The aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD in nine and genital infections in four. Sperm retrieval was accomplished via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was only applied when PESA failed to produce enough spermatozoa for simultaneous ICSI. In six patients, the ICSI procedure was performed with cryopreserved spermatozoa after an initial PESA procedure. Fertilization occurred in 47% of the metaphase II oocytes; embryo transfer was performed in 92% of procedures and resulted in a clinical pregnancy in 13/39 procedures. Ongoing pregnancy was achieved in 10/39 procedures. One pregnancy was terminated early after prenatal investigation showed a cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine pregnancies resulted in the live birth of 10 children, without any congenital abnormalities. Epididymal and testicular retrieved spermatozoa were successfully used for ICSI to treat obstructive azoospermia, and resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI procedures, a success rate of 25.6% per treatment cycle and of 27.7% per embryo transfer.   相似文献   
17.
18.
Screening for chlamydial and gonococcal infection has been strongly recommended for all sexually active women under the age of 26. Advances in the ability to detect infection by nucleic acid detection techniques have improved access to screening methods in routine clinical practices. To meet the increasing demand for testing, a high-throughput system is desirable. We evaluated the performance of the Hybrid Capture 2 CT/GC (HC2) assay with the Digene Rapid Capture System (HC2-RCS). The results of HC2-RCS for endocervical samples from 330 women were compared to those of culture and the COBAS Amplicor PCR. For detection of chlamydial infection, HC2-RCS had a sensitivity and a specificity similar to those of PCR (P > 0.5) and an improved sensitivity compared to that of culture (P = 0.007). For identification of gonococcal infections, all assays performed similarly (P > 0.5). The performance of HC2-RCS was also compared to that of the manual HC2 format (HC2-M) with these samples and with 911 endocervical samples collected previously. The performance of HC2-RCS was equivalent to that of HC2-M; the overall concordance rates for the detection of chlamydia and gonorrhea were 99.7% (kappa = 0.97) and 99.8% (kappa = 0.97), respectively. When the HC2 assay was performed with a semiautomated system application designed for high throughput, it demonstrated high sensitivity and a high specificity for detection of both Chlamydia trachomatis and Neisseria gonorrhoeae.  相似文献   
19.
Widowhood causes four problems: how to replace the functions of the dead spouse and those of the dead parent? who should inherit the property of the dead spouse/ parent? and, where should the surviving family live? Typical solutions to these problems are related to demographic characteristics of developing and developed countries.  相似文献   
20.
Individuals with inflammatory bowel disease (IBD), irritable bowel syndrome (IBS) and reflux frequently experience gastrointestinal symptoms (GIS), potentially enhanced by high-intensity running. Food avoidances, food choices, and GIS in runners with IBS/IBD (n = 53) and reflux (n = 37) were evaluated using a reliability and validity tested questionnaire. Comparisons to a control group of runners (n = 375) were made using a Fisher’s Exact test. Runners with IBS/IBD experienced the greatest amount of exercise-induced GIS followed by those with reflux. Commonly reported GIS were stomach pain/cramps (77%; 53%), bloating (52%; 50%), intestinal pain/cramps (58%; 33%), and diarrhea (58%; 39%) in IBS/IBD and reflux groups respectively. In the pre-race meal, those with IBS/IBD frequently avoided milk products (53%), legumes (37%), and meat (31%); whereas, runners with reflux avoided milk (38%), meat (36%), and high-fibre foods (33%). When considering food choices pre-race, runners with IBS/IBD chose grains containing gluten (40%), high fermentable oligo-, di-, mono-saccharides and polyols (FODMAP) fruits (38%), and water (38%). Runners with reflux chose water (51%), grains containing gluten (37%), and eggs (31%). In conclusion, while many runners with IBS/IBD and reflux are avoiding trigger foods in their pre-race meals, they are also consuming potentially aggravating foods, suggesting nutrition advice may be warranted.  相似文献   
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