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1.
Tetraploid bovine blastocysts were produced experimentally by electrofusion of in vitro matured and fertilized, zona-enclosed two-cell embryos (33-35 hr after initiation of sperm-egg incubation) using three fusion protocols. Field strengths of 1.0, 1.4, and 2.4 kV/cm were tested and the rate of fusion, subsequent cleavage, and blastocyst development were measured for each. High rates of fusion (76.5% +/- 2.8%), cleavage (72.5% +/- 7.4%) and blastocyst development (56.1% +/- 6.4%) were achieved with the application of 1. 4 kV/cm as a single 100-microseconds pulse. Embryos were scored 30 and 60 min after stimulation for fusion. No time effect for fusion, cleavage, or blastocyst development was observed. Chromosome preparations of day 7 blastocysts revealed 12.5% of fused embryos were tetraploid. This is a significant increase from that found in nonfused embryos where spontaneous tetraploidy did not occur. An electrical stimulus of 1.0 kV/cm applied as two 50-microseconds pulses produced significantly less one-cell embryos (64.2% +/- 3.0%) compared to 1.4 kV/cm while cleavage (79.9% +/- 3.4) and blastocyst development (44.6% +/- 4.0%) were not different from that for unexposed control embryos (89.5% +/- 2.3% and 57.2% +/- 3.2%, respectively). Embryos fused at 2.4 kV/cm applied as a single 30-microseconds pulse (69.7% +/- 5.7%) showed significantly lower cleavage (72.1% +/- 3.7%) and blastocyst rates (40.2% +/- 4.6%) compared to the unexposed control.  相似文献   

2.
Changes in amino acid concentrations were investigated in selected regions of rat brain prior to the onset and during the course of epileptiform seizures induced by L-homocysteine. The concentration of gamma-aminobutyric acid (GABA) decreased preictally in substantia nigra (-18%), caudate putamen (-26%), and inferior colliculus (-46%). After seizure onset, the GABA content was further reduced in substantia nigra (-31%) and additionally in hippocampus (-18%). Preictal taurine levels were elevated in globus pallidus (+26%) and caudate putamen (+13%) but returned to normal after seizure onset. However, in hippocampus, taurine decreased both preictally (-22%) and after seizure onset (-56%). Glycine was reduced preictally only in globus pallidus (-13%). After seizure onset the direction of its concentration change varied in the brain regions studied. Glutamate levels decreased preictally in hippocampus (-10%) and hypothalamus (-46%) but increased in globus pallidus (+14%). Normal levels were detectable after seizure onset in hypothalamus and globus pallidus but a further reduction in hippocampus (-59%) and significant reductions in substantia nigra (-15%) and caudate putamen (-17%) were detected. Aspartate was elevated in hippocampus, both preictally (+49%) and after seizure onset (+21%) while at the same phases in globus pallidus a consistent reduction (-30%) was observed. The glutamine content increased preictally in globus pallidus (+41%) and hypothalamus (+36%), and in all brain areas during the ictal phase of seizure, the hippocampus exhibiting a dramatic increase (approximately 300%). The contents of serine and alanine were altered in most regions studied only after seizure onset, with the exception of the hippocampus, where a decrease (-41%) of serine was observed preictally.  相似文献   

3.
4103 cases suspected of mycoses were analysed as to sex, age and site of disease and 3891 were proved cases. This group formed 50% of total mycoses or 13-93% of all dermatoses recorded in the Government General Hospital, Madras, during the period of study. There were 66-26% adult female, 27-6% adult male and 6-14% were below 13 years. Dermatophytoses were found in 73-5%; the other common diseases were tinea versicolor (17-68%) and candidiasis (12-43%). Multiple sites of involvement or more than 1 disease in the same individual were mostly observed. The incidence of piedra (0-1%) and deep mycoses (0-156%) was very low. Mycetoma was the common disease (5/6) in deep mycoses. In dermatophytoses, tinea corporis (49-71%) and tinea cruris (47-85%) commonest; tinea axillaris (3-42%), tinea capitis (1-72%) and tinea barbae (1-29%) were less common. The incidence of tinea manuum, tinea pedis and tinea unguium was similar (4-97%-6-38%). High temperature and humidity were related to the higher incidence of tinea corporis, tinea cruris and tinea versicolor. Mainly children suffered from tinea capitis. All other mycoses were commonly found in adults between 2nd and 3rd decades. In all mycoses but candidiasis, female predominated. Cutaneous candidiasis was mainly a problem of housewives. Among the dermatophytes Trichophyton violaceum was predominant (33-7%) followed by T. rubrum (32-6%). Trichophyton schoenleinii and M. gypseum were rarely isolated. From mycetoma, Madurella mycetomii, Nocardia braziliensis, N. asteroides and Actinomadura spp. were isolated. Demonstration of Cryptococcus laurentii in 1 case is reported in this area for the first time.  相似文献   

4.
The serum samples and corresponding cervical swabs were collected from 50 women with genital warts from Tianjin city, China. The neutralizing antibodies against HPV-16, -18, -58, -45, -6 and -11 in serum samples were tested by using pseudovirus-based neutralization assays and HPV DNAs in cervical swabs were also tested by using a typing kit that can detect 21 types of HPV. The results revealed that 36% (18/50) of sera were positive for type-specific neutralizing antibodies with a titer range of 160–2560, of which 22%(11/50), 12%(6/50), 10%(5/50), 4%(2/50), 4%(2/50) and 2%(1/50) were against HPVs -6, -16, -18, -58, -45 and -11, respectively. Additionally, 60% (30/50) of samples were HPV DNA-positive, in which the most common types detected were HPV-68(18%), HPV-16(14%), HPV-58(12%), HPV-33(8%) and HPV-6, HPV-11, HPV-18 and HPV-52 (6% each). The concordance between HPV DNA and corresponding neutralizing antibodies was 56% (28/50) with a significant difference (P<0.05). The full-length sequences of five HPV types (HPV -42, -52, -53, -58 and -68) were determined and exhibited 98%–100% identities with their reported genomes. The present data may have utility for investigating the natural history of HPV infection and promote the development of HPV vaccines.  相似文献   

5.
The results of 250 cadaver kidney transplants performed at this hospital between May 1968 and December 1974 were analysed. A functioning transplant was defined strictly as one that maintained the recipient in good health with a serum creatinine below 442 mumol/1 (5 mg/100 ml) without any need for dialysis. The proportions of kidneys functioning after one, two, and three years were 40-4%, 33-9%, and 31-1% respectively, the corresponding survival rates of patients being 62-6%, 57-4%, and 43-8%. The primary failure rate overall was 21-6%, while the failure rates for first, second, and third transplants were 18-1%, 39-9%, and 66-7% respectively. Half of the primary failures were attributed to the use of cadaver kidneys with abnormal vasculature or long ischaemic times or originating from non-ventilated donors. Of the initially successful transplants 49% were subsequently lost due to rejection (53%) or death of the patient with a functioning transplant (46%), and of the secondary losses 58% occurred within three months of transplantation. HLA matching of donor and recipient for two or more antigens was associated with a significant increase in transplant survival--46% at three years as opposed to 9-5% at three years for kidneys with poorer matches.  相似文献   

6.
The purpose of this study was to determine the effect of football equipment and running surface on sprint performance in NCAA Division II football players (n = 68). Players were timed in the 40-yd sprint on an indoor rubberized track (Day 1) and on an outdoor, natural-grass football field (Day 2) wearing either regulation football equipment or shorts and a T-shirt. Each player was assigned randomly to perform 2 trials under each condition on each surface, and the average of the 2 trials was used for analysis. Offensive backs, defensive backs, and linebackers were significantly faster than were offensive and defensive linemen in all trials, and subjects were collapsed into 2 groups, backs and linemen. Football equipment significantly impaired performance on the track (-2.8% +/- 1.7%) and the field (-2.9% +/- 1.8%). The increase in body mass due to the football equipment was significantly greater for backs (7.2% +/- 0.7%) than for linemen (6.5% +/- 1.0%), but produced a significantly greater impairment in sprint performance in linemen (-3.3% +/- 1.1%) as compared with backs (-2.5% +/- 1.5%). Sprint performance was significantly and equivalently impaired when running on grass (backs: -2.5 +/- 1.1%; linemen: -2.8 +/- 1.4%) as compared with the track. Thus, running a 40-yd sprint in football equipment on a natural grass field impairs performance by an average of 5.5% (+/- 2.3%) compared with running indoors with minimal apparel. Football equipment and running surface significantly impair sprint performance in college football players, the effect being greater in linemen than in backs, and is likely related to differences in muscle strength/power and body fat.  相似文献   

7.
500 strains of Serratia marcescens isolated in 2003-2005 were examined for drug susceptibility. By using several phenotypic methods it was shown that 67.6% of these strains produced ESBLs. Strains ESBL(-) and ESBL(+) were compared, paying special attention to their susceptibility to various antibiotics. It was revealed that strains ESBL(+) were much more resistant to majority of the investigated drugs. The biggest differences were in the case of amikacin and gentamicin, sensitive about 50% of ESBL(-) and 10% of ESBL(+), ciprofloxacin, sensitive 42% of ESBL(-) and 6.3% of ESBL(+) and trimethoprim/ sulphametoxazole, sensitive 45.8% of ESBL(-) and 9.4% of ESBL(+). Strains ESBL(-) retained a high susceptibility to ceftazidime (68.9%) and cefepime (71%). All strains ESBL(-) as well as ESBL(+) were susceptible to imipenem and meropenem. 78.9% of ESBL(-) and 67.3% of investigated ESBL(+) were susceptible to piperacillin/ tazobactam.  相似文献   

8.
The effects of season (January-March = I; April-June = II; July-September = III; October-December = IV) and ovarian status (freshly ovulated, follicular, luteal, intermediate, or inactive) on the efficiency of the in vitro production of domestic cat embryos were evaluated. Ovaries and testes from cats with access to daylight were collected at local veterinary clinics. A total of 6843 cumulus-oocyte complexes (COCs) were recovered from 363 pairs of ovaries, matured in TCM 199 supplemented with BSA and gonadotropins (IVM), fertilized with epididymal sperm in a medium based on Tyrode albumin lactate pyruvate (IVF), and cultured in synthetic oviduct fluid (SOF) medium supplemented with 10% estrous cow serum (ECS) and essential and nonessential amino acids. The proportion of freshly ovulated, follicular, or luteal ovaries was higher (P < 0.05) in seasons II (64.4%) and III (60.5%) than in seasons I (42.0%) and IV (30.6%). The average number of COCs recovered per donor was not influenced by season. After IVM/IVF, cleavage rates (Day 2) were significantly higher (P < 0.05) in seasons II (mean +/- SEM: 53.1% +/- 1.9%) and III (54.6% +/- 2.8%) than in seasons I (48.4% +/- 1.4%) and IV (44.9% +/- 3.0%). Blastocyst rates on Day 6 were similar in seasons I (25.3% +/- 1.3%), II (28.2% +/- 1.5%), and III (29.6% +/- 2.3%) but were significantly lower (P < 0.01) in season IV (18.6% +/- 2.4%). The corresponding blastocyst rates on Day 8 were 28.9% +/- 1.3%, 33.7% +/- 1.6%, 37.9% +/- 2.3%, and 23.6% +/- 2.6%. In addition, we found a significant effect (P < 0.05) of ovary type; luteal, follicular, and intermediate ovaries yielding a higher proportion of developmentally competent oocytes than did freshly ovulated and inactive ovaries. These data show that the culture system used in our study supports development of IVM/IVF cat oocytes to blastocysts at a higher rate than those obtained with other methods. Although embryos could be produced throughout the year, the efficiency was significantly affected by season and ovary type.  相似文献   

9.
10.
Im GS  Lai L  Liu Z  Hao Y  Wax D  Bonk A  Prather RS 《Theriogenology》2004,61(6):1125-1135
This study investigated the effect of culture media and gas atmospheres on the development of porcine nuclear transfer embryos. Oocytes derived from a local abattoir were matured for 42-44 h and enucleated. Fetal fibroblasts were prepared from a Day 35 porcine fetus. Confluent stage fetal fibroblasts were introduced into the perivitelline space of enucleated oocytes. Fusion and activation were induced simultaneously with two direct current (1.2 kV/cm for 30 micros) in 0.3 M mannitol medium. For parthenogenetic activation, the same pulses were used. In Experiment 1, parthenogenetically activated oocytes were cultured in North Carolina State University-23 (NCSU-23), Porcine Zygote Medium-3 (PZM-3), or Beltsville Embryo Culture Medium-3 (BECM-3). Parthenogenetically activated oocytes cultured in PZM-3 had a higher (P < 0.05) developmental rate to the blastocyst stage (15.2% versus 3.7-9.6%) as compared to BECM-3 or NCSU-23. The number of nuclei in Day 6 blastocysts was higher (P < 0.05) in PZM-3 (23.6) and NCSU-23 (21.4) than BECM-3 (14.2). In Experiment 2, parthenogenetically activated oocytes were cultured in NCSU-23 under a gas atmosphere of 5% CO(2) in air for 6 days (T1), 5% CO(2), 5% O(2), 90% N(2) for 6 days (T2), 5% CO(2) in air for 3 days, then 5% CO(2), 5% O(2), 90% N(2) for 3 days (T3), or 5% CO(2), 5% O(2), 90% N(2) for 3 days, then 5% CO(2) in air for 3 days (T4). Blastocyst formation rates were not different among treatments (12.9 =/-3.6 %, 13.5 +/- 4.2%, 10.8+/-2.4%, and 12.6+/-2.7%, respectively). However, T2 (36.7+/-2.9) and T3 (33.8+/-3.0) resulted in more nuclei per blastocyst than T1 (23.2+/-2.1) or T4 (26.0+/-2.1 ). In Experiment 3, reconstructed porcine nuclear transfer (NT) embryos were cultured in NCSU-23 or PZM-3 under a gas atmosphere of 5% CO(2) in air or 5% CO(2), 5% O(2), 90% N(2). Developmental rates to blastocyst stage for porcine NT embryos cultured in NCSU-23 under a gas atmosphere of 5% CO(2) in air or 5% CO(2), 5% O(2), 90% N(2) were 7.2+/-1.4% and 12.3+/-1.4%, and the number of nuclei was 12.2=/-0.8% and 19.4+/-1.0, respectively. NT embryos cultured in PZM-3 under a gas atmosphere of 5% CO(2) in air or 5% CO(2), 5% O(2), 90% N(2) had developmental rates to blastocyst stage of 18.8+/-1.9 %, and 17.8+/-3.8% the nuclei number was 20.9 +/- 1.9 and 21.9+/-3.3, respectively. NT embryos cultured in NCSU-23 had a higher developmental rate to the blastocyst stage in 5% CO(2), 5% O(2), 90% N(2) than in 5% CO(2) in air (P < 0.05). Regardless of gas atmospheres, NT embryos cultured in PZM-3 had a higher developmental rate (18.3 =/- 1.7% versus 16.9 +/- 1.2%) and nuclei number (21.4 +/-1.8 versus 16.9 +/- 1.2) than in NCSU-23 (P < 0.05). In conclusion, a gas atmosphere of 5% CO(2), 5% O(2), 90% N(2) supported a higher development rate of porcine NT embryos than 5% CO(2) in air when the porcine NT embryos were cultured in NCSU-23. Furthermore, regardless of atmosphere, PZM-3 supported a higher development rate of porcine nuclear transfer embryos than NCSU-23.  相似文献   

11.
Treatment of wheat straw with hot water at 80-95 degrees C for 0.5 h at pH 6.0-8.0 released 41.0-53.0% of the original lipophilic extractives. The chemical compositions of six lipophilic extractives were determined by GC on a medium-length high-temperature capillary column without derivatization, thus giving a method for direct determination of individual components of free fatty and resin acids, sterols, waxes, sterol esters, and triglycerides. The extracts contained 68.7-75.8% lipophilic substances, comprising mainly free fatty acids (25.8-48.4%), waxes (9.4-27.0%), sterols (4.1-8.0%), triglycerides (3.3-11.0%), and sterol esters (2.6-5.1%). Minor amounts of diglycerides (0.3-0.5%), resin acid (0.5-3.1%), and phenolic compounds (0.9-3.6%) were also quantitatively determined in the extractives.  相似文献   

12.
Four yellow-pigmented, gram-negative, chemoorganotrophic aerobic bacteria were isolated from starfish Stellaster equestris (strains 022-2-10T, 022-2-9, and 022-2-12) and soft coral (unidentified species) (strain 022-4-7) collected in the South China Sea. 16S rRNA gene sequence-based analyses of the new organisms revealed that Erythrobacter spp. were the closest relatives and shared the highest similarity of 98.7% to E. citreus, 98.5% to E. flavus, 97.9% to E. litoralis and 97.6% to E. longus. The novel organisms were tolerant to 3-6% NaCl, grew between 10 degrees C and 40 degrees C, and were not able to degrade gelatin, casein, and agar, while degraded Tween 80. Two strains (022-2-9 and 022-2-12) could weakly degrade starch. All strains produced a large pool of carotenoids and did not have Bacteriochlorophyll a. Phosphatidylethanolamine (30-36%), phosphatidylglycerol (39-46%), and phosphatidylcholine (21-27%) were the predominant phospholipids. Sphingoglycolipid was not detected. The major fatty acids were 16:0 (6-11%), 16:1omega7 (12-15%), and 18:1omega7 (46-49%). The two-hydroxy fatty acids, 13:0-2OH, 14:0-2OH, 15:0-2OH, 16:0-2OH were also present. The G + C content of the DNAs ranged from 61 to 62 mol%. The level of DNA similarity among four strains was conspecific and ranged from 94% to 98%. Even though new strains and other species of the genus had rather high level of 16S rRNA gene sequence similarities, DNA-DNA hybridization experiments showed only 33-39% of binding with the DNA of the type strains. On the basis of these results and the significant differences demonstrated in the phenotypic and chemotaxonomic characteristics, it is suggested that the new organisms be classified as a novel species; the name Erythrobacter vulgaris sp. nov. is proposed. The type strain is 022-2-10T (= KMM 3465T = CIP 107841T).  相似文献   

13.
We investigated the effect of thyroid hormone (TH) receptor (TR)alpha and -beta isoforms in TH action in the heart. Noninvasive echocardiographic measurements were made in mice homozygous for disruption of TRalpha (TRalpha(0/0)) or TRbeta (TRbeta(-/-)). Mice were studied at baseline, 4 wk after TH deprivation (using a low-iodine diet containing propylthiouracil), and after 4-wk treatment with TH. Baseline heart rates (HR) were similar in wild-type (WT) and TRalpha(0/0) mice but were greater in TRbeta(-/-) mice. With TH deprivation, HR decreased 49% in WT and 37% in TRbeta(-/-) mice and decreased only 5% in TRalpha(0/0) mice from baseline, whereas HR increased in all genotypes with TH treatment. Cardiac output (CO) and cardiac index (CI) in WT mice decreased (-31 and -32%, respectively) with TH deprivation and increased (+69 and +35%, respectively) with TH treatment. The effects of CO and CI were blunted with TH withdrawal in both TRalpha(0/0) (+8 and -2%, respectively) and TRbeta(-/-) mice (-17 and -18%, respectively). Treatment with TH resulted in a 64% increase in LV mass in WT and a 44% increase in TRalpha(0/0) mice but only a 6% increase in TRbeta(-/-) mice (ANOVA P < 0.05). Taken together, these data suggest that TRalpha and TRbeta play different roles in the physiology of TH action on the heart.  相似文献   

14.
A double staining method involving the sequential use of monoclonal OKT hybridoma antibodies applied in the colloidal immunogold method and followed by a simultaneously capturing azo dye method for the detection of acid alpha-naphthyl acetate esterase (ANAE) is described. Mononuclear leukocytes isolated from human peripheral blood using a Ficoll-Hypaque density gradient were stained. M-pattern ANAE-positive monocytes (diffuse staining) were excluded from the lymphocyte counts. 80 +/- 5% of all lymphocytes were T-pattern ANAE positive (dot-like staining) and 77 +/- 3% were OKT3 positive. 86 +/- 6% of all ANAE-positive T-pattern lymphocytes were also OKT3 positive, and 89 +/- 6% of all OKT3-positive lymphocytes were also ANAE positive. This indicates that ANAE is a good marker for total human T lymphocytes. 53 +/- 10% of human peripheral blood lymphocytes were OKT4 positive and 87 +/- 8% of all OKT4-positive lymphocytes were also ANAE positive. 30 +/- 6% of all lymphocytes were OKT8 positive, and only 26 +/- 18% of all OKT8-positive lymphocytes were ANAE negative. This indicates that ANAE cannot be used to distinguish T-helper and T-suppressor lymphocytes as identified by monoclonal antibodies.  相似文献   

15.
16.
In captive Asian elephants, there is a strong need for production of female offspring to enhance reproduction, counter premature aging processes in female animals and reduce challenging management situations derived from husbandry of several bulls in one institution. Artificial insemination of flow cytometrically sex-sorted spermatozoa offers the possibility to predetermine the sex of offspring with high accuracy. The aims of this study were to determine a suitable semen extender and basic parameters for flow cytometrical sex-sorting of Asian elephant spermatozoa. In total 18 semen samples were collected by manual rectal stimulation from one bull. Sperm quality parameters and sex sortability of spermatozoa were evaluated after dilution in three semen extenders (MES-HEPES-skim milk, MES-HEPES, TRIS-citric acid) and DNA staining. MES-HEPES-skim milk was the only semen extender found suitable to sex Asian elephant spermatozoa. From 18 ejaculates collected, 12 were successfully sorted with a purity of 94.5+/-0.7% at an average sort rate of 1945.5+/-187.5 spermatozoa per second. Sperm integrity, progressive and total motility were 42.6+/-3.9%, 48.1+/-3.3%, 59.4+/-3.8% after DNA labelling, and 64.8+/-3.2%, 58.0+/-5.0%, 70.8+/-4.4% after sorting, respectively. After liquid storage of sorted spermatozoa for 12h at 4 degrees C, sperm integrity, progressive and total motility were 46.4+/-5.2%, 32.2+/-4.2% and 58.2+/-3.9%, respectively. The obtained results provide a promising base to inseminate Asian elephants with sexed semen.  相似文献   

17.
Nuclear transfer (NT) techniques have advanced in the last few years, and cloned animals have been produced from somatic cells in several species including pig. In this study we examined the feasibility of using granulosa-derived cells (GCs) as donor cells combined with a microinjection procedure to transfer those nuclei. In vitro matured oocytes were enucleated by aspirating the first polar body and adjacent cytoplasm. Mural GCs infected with an enhanced green fluorescence protein (EGFP) gene were serum-starved (0.5% serum, 7 days), injected directly into cytoplasm of enucleated oocytes and the oocytes were electrically activated. The reconstructed embryos were cultured for 7 days and stained with Hoechst 33342 to determine the number of nuclei. Non-manipulated oocytes were electrically activated and cultured as controls. At 9 h post-activation, the pronuclear formation rates were 78.7+/-3.7% in NT and 97.4+/-4.4% in controls at 9 h post-activation. After 7 days culture, the cleavage rates were 24.5+/-7.2% in NT and 79.3+/-5.6% in controls. The blastocysts formation rates were 4.9+/-2.4% in NT and 26.8+/-3.8% in controls. To examine the effect of activation time on development of NT embryos, oocytes were activated at 0-0.5, 1-2, or 3-4 h post-injection. At 18 h post-activation the pronuclear formation rates were higher (62.5+/-7.3%) in the 3-4 h group as compared to the 0-0.5 h (22.0+/-12.5%) or 1-2h (44.5+/-6.3%) groups (P<0.05). However, the cleavage rates (9.6+/-4.6 to 10.7+/-4.2%) and the blastocysts formation rates (1.2+/-2.4 to 4.9+/-3.7%) were not different among treatments (P>0.05). The mean cell number of blastocysts was 15.7+/-5.7 in NT and 25.3+/-24.7 in controls. Green fluorescence was observed in roughly half of the embryos from the one-cell to the blastocyst stage. These results indicate that granulosa-derived cell nuclei can be remodeled in the cytoplasm of porcine oocytes, and that the reconstructed embryos can develop to the blastocyst stage. In addition, EGFP can be used as a marker for gene expression of donor nuclei.  相似文献   

18.
The activity profile of men's competitive surfing was investigated during an international contest. Forty-two male surfers were filmed during 42 elimination heats. Surfers' activities were classified into 1 of 4 distinct categories (paddling, wave riding, stationary, and miscellaneous). The surfers were paddling and stationary 51% (25-70%) and 42% (23-72%) of the total time, respectively. Wave riding accounted for 4% (2-7%) of the total time, whereas miscellaneous activity accounted for the remaining 2% (0.1-6%) of the total time. The frequency (average number of motions in a heat) of each activity was 26 for paddling (15-37); 17 for stationary (10-26); 5 for wave riding (2-8); and 6 for miscellaneous activity (1-13). The mean duration lengths of the activities were 30.1 seconds (1-286 seconds), 37.7 seconds (1-413 seconds), 11.6 seconds (1-44 seconds), and 5 seconds (1- 31 seconds) for paddling, stationary, wave riding, and miscellaneous activities, respectively. Most of the paddling bouts ( approximately 60%) were performed at time intervals of between 1 and 20 seconds. Approximately 50% (50.9%) of the rest intervals were between 1 and 20 seconds in duration. The results showed that surfing is an intermittent activity characterized by a large variability and random distribution of each parameter analyzed. This information can be used to assist in the development of fitness training programs and physiological testing for competitive surfers.  相似文献   

19.
A total of 678 bovine blastocysts, which had been produced by in vitro maturation, fertilization, and culture, were placed into plastic straws and were vitrified in various solutions of ethylene glycol (EG) + polyvinylpyrrolidone (PVP). Part of the straw was loaded with TCM199 medium + 0.3 M trehalose as a diluent; the diluent portions of the straw were prefrozen to either -30 or -196 degrees C. Then, the embryos suspended in the vitrification solution were pipetted into the balance of the straw and vitrified by direct immersion into liquid nitrogen. For thawing, the straws were warmed for 3 s in air and 20 s in a water bath at 39 degrees C and then agitated to mix the diluent and cryoprotectant solution for 5 min followed by culture in TCM199 + 10% FCS + 5 + microg/ml insulin + 50 microg/ml gentamycin sulfate for 72 h. Variables that were examined were the time of exposure to EG prior to vitrification, the PVP concentration, and the temperature of exposure to EG + PVP prior to vitrification. Survival and hatching rates of the blastocysts exposed to 40% EG in four steps at 4 degrees C were higher than those of embryos exposed in two steps (81.3 +/- 4.3% and 80.2 +/- 3.4% vs 67.6 +/- 4.5% and 71.5 +/- 4.7%, respectively; P < 0.05). The same indices were superior following vitrification-thawing of the blastocysts in 40% EG + 20% PVP than it was in 40% EG + 10% PVP (76.1 +/- 5.5% vs 63.7 +/- 1.8%; P < 0.05; and 61.6 +/- 6.0% vs 70.5 +/- 4.7%; P < 0.01, respectively). Exposure to the vitrification solution (40% EG + 20% PVP) at higher temperatures (37.5 degrees C vs 4 degrees C) reduced both survival and hatching rates (45.8 +/- 6.9% vs 83.9 +/- 4.4% and 41.5 +/- 1.8% vs 64.0 +/- 4.7%, respectively; P < 0.001). These results indicate that blastocysts vitrified after prefreezing the diluent portions of the straws do favor developmental competence of in vitro produced embryos.  相似文献   

20.
The objective of this study was to compare CA 72-4 with CEA and CA 19-9 in gastrointestinal malignancies. CA 72-4 was assayed by radioimmunoassay and CEA and CA 19-9 with the Abbott IMx analyser. The study included 52 patients with gastrointestinal cancer and 20 controls with benign gastrointestinal diseases. The 52 cases showed marker sensitivities of 39%, 49% and 35% for CA 72-4, CEA and CA 19-9, respectively, and 64% when the markers were combined. Marker expression in serum was highest in colorectal carcinoma followed by gastric and esophageal carcinoma. The sensitivities of the individual markers in colorectal, gastric and esophageal carcinomas, respectively, were: CA 72-4, 56%, 32% and 18%; CEA, 83%, 33% and 18%; CA 19-9, 53%, 25% and 18%. The sensitivity of the three markers in combination was 89%, 50% and 46% in colorectal, gastric and esophageal cancer, respectively. The specificity of CA 72-4, CEA and CA 19-9 was 100%, 72% and 86%, respectively. However, CA 72-4 is not a useful a marker for gastrointestinal cancers because of its poor sensitivity. CEA, which had the best overall sensitivity and a reasonable specificity, was the most useful single marker, especially for colorectal cancer. Whereas the single markers were not useful in gastric and esophageal cancer, the combination of the three may be.  相似文献   

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