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1.
We have inferred the first empirically supported hypothesis of relationships for the cosmopolitan butterfly subfamily Satyrinae. We used 3090 base pairs of DNA from the mitochondrial gene COI and the nuclear genes EF-1alpha and wingless for 165 Satyrinae taxa representing 4 tribes and 15 subtribes, and 26 outgroups, in order to test the monophyly of the subfamily and elucidate phylogenetic relationships of its major lineages. In a combined analysis, the three gene regions supported an almost fully resolved topology, which recovered Satyrinae as polyphyletic, and revealed that the current classification of suprageneric taxa within the subfamily is comprised almost completely of unnatural assemblages. The most noteworthy findings are that Manataria is closely related to Melanitini; Palaeonympha belongs to Euptychiina; Oressinoma, Orsotriaena and Coenonympha group with the Hypocystina; Miller's (1968). Parargina is polyphyletic and its components group with multiple distantly related lineages; and the subtribes Elymniina and Zetherina fall outside the Satyrinae. The three gene regions used in a combined analysis prove to be very effective in resolving relationships of Satyrinae at the subtribal and tribal levels. Further sampling of the taxa closely related to Satyrinae, as well as more extensive sampling of genera within the tribes and subtribes for this group will be critical to test the monophyly of the subfamily and establish a stronger basis for future biogeographical and evolutionary studies.  相似文献   

2.
The survival of indigenous enteric viruses in samples of unconcentrated and concentrated waste water sludge eluates, which had been prepared using a combination beef extract elution - organic flocculation concentration procedure, was studied at 2, 23, and -70 degrees C. Changes of virus titer occurring in the samples were followed during an 84-day observation period, with rates of change then calculated by least-squares regression. Virus survival in both types of eluates was statistically dependent (p less than or equal to 0.05) upon storage temperature. Based upon the observed rates of inactivation the average times which would be required for a 90% decrease (one log10 unit) in virus titer for unconcentrated eluates are 27 days at 23 degrees C, 198 days at 2 degrees C, and 375 days at -70 degrees C. The calculated average times required for a 90% decrease in virus titer for concentrated eluates are 22 days at 23 degrees C, 132 days at 2 degrees C, and 246 days at -70 degrees C. In both types of eluates the rates of virus inactivation at 2 degrees C were statistically different from those observed at 23 degrees C, but not different from those observed at -70 degrees C. The three study temperatures were selected to approximate holding of samples in an air-conditioned room, fluid on wet ice (H2O), and frozen on dry ice (CO2).  相似文献   

3.
A rearing method for the fleaCeratophyllus (Monopsyllus) sciurorum sciurorum, a pest on farmed mink in Europe, has been developed. The behaviour of egg-laying and the development period are described at 23 °C and 80% r.h. The eggs ofC. sciurorum sciurorum hatched after 4–7 days and cocoons were formed 10–12 days later. The development period from egg to newly emerged adult was 23–32 days. Females emerged, in general, earlier than males.  相似文献   

4.
Fatty (fa/fa) rats accumulate more adipose mass than their littermates soon after birth, but they first appear obese during the fourth week of life. We analyzed the effects of fa genotype on growth of pups housed with their dams through 4 wk of age. The fa genotype effects on daily gain were undetectable from 7 to 22 days of age but became highly significant (P = 10(-18)) at 23 days of age. When litters were reduced to 4 pups, fa genotype effects on daily gain also became detectable at 23 days of age. The fa genotype effects on daily gain, stomach contents weight, liver weight, and plasma insulin of rats killed from 20 to 24 days of age displayed a marked genotype by age interaction, becoming highly significant at 23 days of age. These changes occur without the environmental changes induced by separating pups from their dams. These observations suggest that a developmental switch triggers hyperphagia and rapidly increases growth rate of fatty rats after 22 days of age.  相似文献   

5.
We examined Ixodes ricinus embryos between 18 and 28 days of development with light, scanning and transmission electron microscopy. The differences in inner structure attested to establish three successive developmental stages: days 18-20, day 23, and days 26-28. Between 18 and 20 days the embryos are at early stages of organogenesis. Salivary glands cannot be identified at that stage. In 23-day-old embryos salivary glands are already outlined but the structure of alveoles is still different from that in larvae in which the embryonic development has been completed. Gland cells start to form alveoles and become active between 26 and 28 days of the development.  相似文献   

6.
Twenty-five years of reproductive and birth data from a Macaca cyclopis colony at the New England Regional Primate Research Center (NERPRC) indicate that these animals are seasonal breeders with a birth peak between February and May. Interbirth intervals have a mean of 587.5 ± 45.6 days. The age at first reproduction for females is 5.08 ±.357 years and for males 5.01 ± .94. The normal menstrual cycle length ranges from 24–31 (mean 27.9 ± .506) days, with “offseason” long cycles ranging from 43–69 days. For 10 females studied prospectively, the sex skin color cycle ranged from 23–34 days and exhibited no long cycles. The peak estradiol value was 1.35 nmol/L on day 11 (range 10–12) of the menstrual cycle. Estradiol values ranged from 0.7–2.0 nmol/L. The peak progesterone value was 23 nmol/L on day 21 (17–23). Progesterone levels ranged from 10–42 nmol/L. The observed lower fecundability of M. cylopis in a timed mating program is consistent with later ages at first reproduction and longer interbirth compared to the other species in breeding colonies at NERPRC. © 1995 Wiley-Liss, Inc.  相似文献   

7.
H T Epstein  K Fenton  S Shimpach 《Life sciences》1991,49(16):1169-1172
Starting at parturition and continuing until weaning, mothers of five mouse litters received tap water while five others had 10 mg PbAc/ml in their drinking water. The offspring receiving lead from the mothers had significantly lower body weights after the first days of receiving lead; their slowed body growth led to a 2-day delay of onset (usually at 16-18 days) of their last rapid body growth stage. They also had significantly smaller brain weights between age 14 days and weaning (23 days). The onset of rapid brain growth was delayed from its usual onset at 16-18 days to about 22-23 days before rising to about the same value as the control mice at 26 days. Thus, the initial effect on brain growth is decidedly greater than on body growth, though brain weight later reaches close to the control value.  相似文献   

8.
Catechol 2,3-dioxygenase (C23O) is an extradiol dioxygenase that plays an important role in degrading aromatic compounds such as those found at polluted sites. However, little is known about the diversity of C23O genes in unpolluted environments. In such environments, various factors, including the quality and quantity of dissolved organic matter (DOM), could influence the composition and behaviour of bacterial community possessing C230 genes. We investigated C23O genes in bacteria responding to DOM from various sources in a eutrophic lake by PCR and cloning. Six microcosms filled with lake water containing indigenous bacteria and DOM from different sources were incubated for 10 days. After 1 or 2 days of incubation, C23O genes were detected in the microcosms enriched with DOM recovered from inflow river water and humus from reed grass. The sequences were very diverse but had features conserved in extradiol dioxygenases. The clone libraries generated on day 2 showed distinctive compositions among microcosms, indicating that bacteria possessing a variety of C23O genes responded differently to DOM from different sources. After 10 days of incubation, C23O genes in a previously unidentified gene cluster, 'Cluster X', became dominant in the libraries.  相似文献   

9.
The aim of this study was to compare four methods of estrus resynchronization performed 23 days after timed artificial insemination (TAI) plus estrus observation in Bos indicus cows. Eight hundred fourteen lactating Nelore cows were submitted to TAI and then randomly assigned to one of the five following treatments: R23 (resynchronization without eCG), R23/200 (resynchronization with 200 IU of eCG), R23/300 (resynchronization with 300 IU of eCG), R23/TCR (resynchronization with temporary calf removal [TCR]), and a control group, with estrus observation followed by AI (with no resynchronization). Treatment consisted of a progesterone device plus administration of estradiol benzoate on Day 0; on Day 8, the device was removed and cloprostenol was applied, together with estradiol cypionate. Also on Day 8, either eCG was administered or TCR was performed in the resynchronized groups, except for R23. The females were inseminated 48 hours after device removal or TCR (33 days after the first TAI). The control group was kept under estrus observation from 18 to 23 days after the first TAI and was inseminated 12 hours after detection of estrus. The first pregnancy evaluation was performed using ultrasound examination 31 days after the first TAI. After 30 days of the resynchronization, a second pregnancy evaluation was performed and the animals in the R23/300 and R23/TCR groups achieved the highest conception rates, 76.6% and 74.0%, respectively (P < 0.05). There were no differences between the conception rates of the animals in the R23/200 (63.3%), R23 (61.3%), and control (54.3%) groups (P > 0.05). These results suggest that estrus resynchronization at 23 days after TAI can effectively improve the conception rate of lactating Bos indicus cows in a short time period. Furthermore, resynchronization with 300 IU of eCG or with TCR provided the best results.  相似文献   

10.
The stability of indigenous enteric viruses in samples of settled primary and mixed-liquor activated sludges was studied at 2, 23, and -70 degrees C. Changes of virus titer which occurred in these samples were followed during an 84-day observation period, with rates of change then calculated by least-squares regression. Virus survival was found to be statistically dependent (p less than or equal to 0.05) upon storage temperature but not sludge solids content. Based upon the observed rates of inactivation, the average times which would be required for a 90% decrease in virus titer are 26 days at 23 degrees C, 180 days at 2 degrees C, and 163 days at -70 degrees C. As a group, the rates of virus inactivation observed at 2 degrees C were statistically different (p less than or equal to 0.05) from those observed at 23 degrees C, but not different from those observed at -70 degrees C. The three study temperatures were selected to approximate holding of samples in an air-conditioned room, on wet ice (H2O), and on dry ice (CO2).  相似文献   

11.
There are situations in which adult female rats release increased amounts of follicle-stimulating hormone (FSH) independent of increased luteinizing hormone (LH) release. This results from, at least in part, a selective increase in the basal FSH release rate. We investigated whether an increase in the basal FSH release rate is contributory to the rise in serum FSH levels which occurs independent of a rise in serum LH levels in the immature female rat. Rats had high serum FSH concentrations on days 7 and 15 after birth, low serum FSH levels on day 23, and low serum LH levels on all three days. In contrast, anterior pituitary gland (APG) FSH and LH concentrations and contents increased from day 7 to day 15 and the contents increased further from day 15 to day 23. Similarly, basal FSH and LH release rates per mg APG or per APG, as assessed by measurement of FSH and LH released into culture medium containing APG(s) from different aged rats, increased from day 7 to day 15 but did not increase further between days 15 and 23. The results indicate that unlike situations observed to date in adult female rats, a mechanism(s) other than an increase in the basal FSH release rate is involved in selective FSH release in the immature female rat.  相似文献   

12.
1. The rate of fatty acid synthesis by mammary explants from rabbits pregnant for 16 days or from rabbits pseudopregnant for 11 days was stimulated up to 15-fold by culturing for 2-4 days with prolactin. This treatment initiated the predominant synthesis of C(8:0) and C(10:0) fatty acids, which are characteristic of rabbit milk. 2. Inclusion of insulin in the culture medium increased the rate of synthesis of these medium-chain fatty acids. By contrast the inclusion of corticosterone led to the predominant synthesis of long-chain fatty acids. When explants were cultured for 2-4 days with insulin, corticosterone and prolactin, the rate of fatty acid synthesis increased up to 42-fold, but both medium- and long-chain fatty acids were synthesized. 3. These results show that the stimulus to mammary-gland lipogenesis and the initiation of synthesis of medium-chain fatty acids observed between days 16 and 23 of pregnancy in the rabbit can be simulated in vitro by prolactin alone. 4. When mammary explants from rabbits pregnant for 23 days were cultured for 2 days with insulin, corticosterone and prolactin, the rate of fatty acid synthesis increased fivefold, but there was a preferential synthesis of long-chain fatty acids. Culture with prolactin alone had little effect on the rate or pattern of fatty acids synthesized. 5. The results are compared with findings in vivo on the control of lipogenesis in the rabbit mammary gland, and are contrasted with the known effects of hormones in vitro on the mammary gland of the mid-pregnant mouse.  相似文献   

13.
We examined Ixodes ricinus embryos between 18 and 28 days of development with light, scanning and transmission electron microscopy. The differences in inner structure attested to establish three successive developmental stages: days 18–20, day 23, and days 26–28. Between 18 and 20 days the embryos are at early stages of organogenesis. Salivary glands cannot be identified at that stage. In 23-day-old embryos salivary glands are already outlined but the structure of alveoles is still different from that in larvae in which the embryonic development has been completed. Gland cells start to form alveoles and become active between 26 and 28 days of the development. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

14.
Bt玉米秸秆分解对土壤酶活性和土壤肥力的影响   总被引:26,自引:0,他引:26  
通过室内实验,研究了Bt玉米34B24和同源常规品种34B23、Bt玉米农大61和常规品种农大3138秸秆分解对土壤酶活性和土壤肥力的影响.结果表明,与34B23处理相比,34B24处理的土壤蛋白酶和酸性磷酸酶活性在观测期没有显著差异;7d时土壤脱氢酶活性显著提高,1、4、60和7d土壤蔗糖酶活性显著提高;30d时土壤脲酶活性显著提高,4d和7d时则土壤脲酶活性显著降低.2个Bt玉米处理和2个常规玉米处理的土壤酶活性也在某些时间有显著差异.秸秆分解90d后,34B24处理比34B23处理.显著降低了土壤速效磷和速效钾含量.以上差异与不同秸秆的化学构成有关,Bt基因的转化过程可能会影响受体作物秸秆的化学成分.应建立不同土壤类型土壤酶活性的标准分级体系,以便科学评价Bt玉米秸秆分解对土壤质量的影响.  相似文献   

15.
Kim HS  Lee GS  Hyun SH  Lee SH  Nam DH  Jeong YW  Kim S  Kang SK  Lee BC  Hwang WS 《Theriogenology》2004,61(7-8):1381-1393
The effect of replacing 5.5 mM glucose in North Carolina State University (NCSU)-23 medium with 0.5 mM pyruvate/5.0 mM lactate on porcine IVF embryo development was investigated in Experiment 1. Culturing embryos with pyruvate/lactate for 7 days or with pyruvate/lactate from Days 0 to 2, and then glucose from Days 2 to 7 improved cleavage rates. In Experiment 2, embryos were cultured for 7 days in pyruvate/lactate containing NCSU-23 medium supplemented with 0.05% PVA, 0.4% BSA or 10% fetal bovine serum (FBS). The BSA supplement increased the rates of cleavage, blastocyst formation, and the number of total cells in blastocysts. In Experiment 3, embryos were cultured in pyruvate/lactate containing NCSU-23 medium supplemented with 0.4% BSA for 7 days (BSA-PL), 0.4% BSA from Days 0 to 4 and then 10% FBS from Days 4 to 7 (BSA-PL-->F ) or 0.4% BSA from Days 0 to 7 with addition of 10% FBS (BSA-PL + F ) at Day 4. More blastocysts in BSA-PL--> F and hatching or hatched blastocysts in BSA-PL-->F and BSA-PL+F were obtained. Total cell number in blastocysts derived from BSA-PL-->F and BSA-PL+F were increased. Our results demonstrated that supplementing pyruvate/lactate containing NCSU-23 medium with 0.4% BSA for 4 days and replacing it with 10% FBS for another 3 days improved porcine IVF embryo development.  相似文献   

16.
M. S. T. Abbas 《BioControl》1989,34(4):447-451
Trichogramma buesi was reared in the laboratory on eggs of the Mediterranean flour moth,Anagasta kuehniella. The incubation period of the parasite's egg was 27 h at 23 °C and 22 h at 27 °C. The larval stage lasted 3.6 and 3.2 days, the pre-pupa lasted 16 and 23 h, and the pupa lasted 5.4 and 4.6 days at 23° and 27°C, respectively. The total developmental time (from egg to adult) averaged 9.2, 9.4, and 9.1 days when the parasite was reared on eggs ofPieris rapae, Spodoptera littoralis, andA. kuehniella, respectively, at 27 °C. Sex ratio inT. buesi was 1 ♂: 1 ♀ in nature and 1 ♂: 1.3 ♀ in the laboratory. The daily and total numbers or progeny produced/female were 5.1 and 98.2 adults, respectively. The parasite female, fed on honey, lived 10.7 days at 27 °C and 12.1 days at 23 °C. Percentages of parasitism byT. buesi on eggs ofP. rapae collected from cabbage fields ranged between 0 and 31.5 % in 1985 and betwcen 0 and 36.4% in 1986 during July through December. The respective figures on eggs collected from turnip fields were 16–42.2% and 12.5–32.1% during November and December.   相似文献   

17.
Captive muntjac fed on vegetation had a daily defecation rate of 7 to 8.2.pellet groups. Even in the cold month of February 97.6% of pellets decayed within 80 days but for 8 other months the range was 4 to 23 days. Emphasis is given to the need for site-specific information when decay rate is required to assess population size from dung counts. The morphology, dimensions, weight and group size of pellets are described as an aid to distinguish them from the faeces of other cervids.  相似文献   

18.
The prophylactic effects of heat-killed cells of Enterococcus faecalis FK-23 (FK-23 preparation) on experimental candidiasis were investigated in normal and leukopenic mice. In cyclophosphamide-induced leukopenic mice, oral or intraperitoneal administration of the FK-23 preparation at a daily dose of 1.25 or 5 mg/mouse for 3 consecutive days prior to Candida albicans infection significantly prolonged survival periods of the infected mice, and decreased viable counts of C. albicans recovered from their kidneys. In normal mice, the FK-23 preparation administered at dosages ranging from 0.63 to 10 mg/mouse/day for 3 consecutive days was ineffective, while in leukopenic mice, the FK-23 administered orally caused a facilitated recovery in the number of white blood cells including neutrophils. Furthermore, intraperitoneal administration of the FK-23 preparation into mice augmented the anti-Candida activity of immunocompromised peritoneal exudate cells obtained from the animals. These results suggested the potential usefulness of the FK-23 preparation as a prophylactic agent for the management of patients with opportunistic fungal infections.  相似文献   

19.
Data are presented on the mean aftersurvival of male B6CF1 mice exposed for 22 h per day, 5 days per week, to 60Co gamma radiation at dose rates of 1.36 to 12.64 x 10(-3) cGy/min for 23 weeks or 1.36 to 6.32 x 10(-3) cGy/min for 59 weeks. For deaths from all causes, linear dose-response curves were obtained with slopes (days of life lost/cGy) of 0.158 +/- 0.016 and 0.077 +/- 0.002 for 23- and 59-week exposures, respectively. These values were not significantly altered when the analysis was restricted to those mice dying with tumors (92% of the total) or to those presumably dying from tumors (82% of the total). Analysis of mortality rates showed that about 90% of the radiation-specific excess mortality was tumor related. The 59-week exposure series induced only a small increase in the number of days of life lost/cGy/weekly fraction over that induced by 23 weeks of irradiation, 4.53 +/- 0.15 compared to 3.64 +/- 0.36 days lost/cGy/weekly fraction. This lower than expected value for 59 weeks of exposure may signal the approach to the final linear, additive, injury term postulated from earlier studies at this laboratory with low-dose-rate, daily, duration-of-life 60Co gamma irradiation.  相似文献   

20.
The age of Colorado beetles can be determined, for at least 20–23 days after emergence, by means of the colour of the membranous hind-wings. The colour changes are described and a series of colour reproductions illustrate the appearance of a selection of wings during the first 25 days after emergence from the soil.  相似文献   

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