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排序方式: 共有240条查询结果,搜索用时 15 毫秒
101.
James F Grutsch Patricia A Wood Jovelyn Du-Quiton Justin L Reynolds Christopher G Lis Robert D Levin Mary Ann Daehler Digant Gupta Dinah Faith T Quiton William JM Hrushesky 《Journal of circadian rhythms》2011,9(1):1-12
Background
Many previous studies have documented seasonal variation in suicides globally. We re-assessed the seasonal variation of suicides in Finland and tried to relate it to the seasonal variation in daylength and ambient temperature and in the discrepancy between local time and solar time.Methods
The daily data of all suicides from 1969 to 2003 in Finland (N = 43,393) were available. The calendar year was divided into twelve periods according to the length of daylight and the routinely changing time difference between sun time and official time. The daily mean of suicide mortality was calculated for each of these periods and the 95% confidence intervals of the daily means were used to evaluate the statistical significance of the means. In addition, daily changes in sunshine hours and mean temperature were compared to the daily means of suicide mortality in two locations during these afore mentioned periods.Results
A significant peak of the daily mean value of suicide mortality occurred in Finland between May 15th and July 25th, a period that lies symmetrically around the solstice. Concerning the suicide mortality among men in the northern location (Oulu), the peak was postponed as compared with the southern location (Helsinki). The daily variation in temperature or in sunshine did not have significant association with suicide mortality in these two locations.Conclusions
The period with the longest length of the day associated with the increased suicide mortality. Furthermore, since the peak of suicide mortality seems to manifest later during the year in the north, some other physical or biological signals, besides the variation in daylight, may be involved. In order to have novel means for suicide prevention, the assessment of susceptibility to the circadian misalignment might help. 相似文献102.
EM García JJ Calvete L Sanz J Roca EA Martínez JM Vázquez 《Reproduction in domestic animals》2009,44(2):200-205
The aim of this study was to evaluate how different protein profiles of seminal plasma (SP) fractions affect sperm functionality in vitro. Ejaculates from three boars were separated into six fractions. The fractions differed from each other in their sperm content, in their total SP protein content, and their spermadhesin PSP-I/PSP-II and heparin-binding protein (HBP) concentrations. Spermatozoa were mainly recovered in fraction 2 (sperm-rich fraction, >1800 × 106 spermatozoa/ml), whereas the pre-sperm fraction 1 and the post-sperm fractions 4–6 contained low numbers of spermatozoa (<500 × 106 /ml). Except in fraction 2, the total SP protein concentration and the concentration of both, spermadhesin PSP-I/PSP-II and the HBPs increased with fraction order. Distinct time-dependent effects were observed on motility characteristics and membrane integrity of highly diluted boar spermatozoa upon incubation with a 10% dilution of the SP from each fraction. The highest sperm viability was recorded after exposure for 5 h to fraction 2, followed by fractions 1 and 3. The percentages of motile spermatozoa also differed significantly among fractions after 5 h of incubation. Spermatozoa incubated with SP of fractions 1–3 showed the highest percentage motility. We conclude that different SP fractions exert distinct effects on the functionality of highly diluted boar spermatozoa. Fractions 1–3 appear to promote sperm survival, whereas fractions 4–6 seem to be harmful for preserving the physiological functions of highly diluted boar spermatozoa. 相似文献
103.
Challenges in Pig Artificial Insemination 总被引:4,自引:0,他引:4
J Roca JM Vázquez MA Gil C Cuello I Parrilla EA Martínez 《Reproduction in domestic animals》2006,41(S2):43-53
104.
Vilhelmiina Huuskonen JM Lynne Hughes Elisa Estaca Bañon Eleanor West 《Veterinary anaesthesia and analgesia》2013,40(1):74-82
ObjectiveTo investigate whether intratesticular injection of lidocaine pre-surgery would reduce the intraoperative responses to elective castration in dogs.Study designDouble-blinded, randomized, controlled, prospective clinical study.AnimalsForty-two client-owned dogs weighing 2.2–38.4 kg and aged between 4.5 and 56 months.MethodsGroup L dogs received an intratesticular injection of 2% lidocaine (2 mg kg?1) and Group S an identical volume of saline prior to surgery. Premedication was with acepromazine and morphine intramuscularly. Anaesthesia was induced with propofol intravenously and maintained with isoflurane vaporized in oxygen. Heart rate (HR), mean arterial pressure (MAP), respiratory rate (fR), end-tidal isoflurane (Fe′ISO) and carbon dioxide concentrations, oxygen saturation and ECG were monitored during surgery. Fe′ISO was maintained at 1.0 ± 0.1%. Supplemental propofol was given in response to gross movement.ResultsGroup L had significantly lower maximum values for both HR and MAP. Group L displayed significantly smaller increases in HR during exteriorization of the first testis than Group S. There was an overall significant difference in MAP between groups during all surgical events (p = 0.041) and time points (p = 0.002). In univariate analysis, Group L showed significantly less changes in MAP during skin incision, exteriorization of the first testis and clamping of both spermatic cords. Group S reached its highest fR significantly earlier. Group L (eight dogs) required additional propofol 33 ± 18 minutes after the start of surgery and Group S (seven dogs) at 19 ± 17 minutes; this difference was not statistically significant. Seven dogs in Group L and 12 dogs in Group S required rescue analgesia with morphine (GCMPS-SF score ≥6); this difference was not statistically significant. No adverse effects were reported postoperatively.Conclusions and clinical relevanceBased on this study, the authors recommend the use of intratesticular lidocaine for surgical castration in dogs. 相似文献
105.
An improved enzyme preparation for rapid mass production of protoplasts as seed stock for aquaculture of macrophytic marine green algae 总被引:1,自引:0,他引:1
C.R.K. Reddy Shikh Dipakkore G. Rajakrishna Kumar Bhavanath Jha Donald P. Cheney Yuji Fujita 《Aquaculture (Amsterdam, Netherlands)》2006,260(1-4):290-297
Preparation of protoplasts and their subsequent applications for both basic and applied research of marine macroalgae remains largely under developed due to lack of development of reliable methods with consistent yields of viable protoplasts. An improved enzyme preparation with a single commercial enzyme, e.g. 2% Cellulase Onozuka R-10 in 1% NaCl solution, was developed to produce protoplasts rapidly from different green algal genera of Ulva, Enteromorpha and Monostroma. The simple dissolution of enzyme powder in 1% NaCl resulted in exclusion of 2% Macerozyme R-10 from the mixture consisting of 2% Cellulase Onozuka R-10 with 3% NaCl earlier reported as superior for the same algae. Optimal conditions for the isolation of maximum yields of viable protoplasts were found to be with 2% Cellulase Onozuka R-10 incubated at 20 °C for 2 h in 1% NaCl solution with 0.8 M mannitol adjusted to pH 6.0. The protoplast yield with optimized enzyme mixture was as high as 102.8 × 106 cells g− 1 f. wt for M. oxyspermum while it was in the range of 74.4–88.6 × 106 cells g− 1 f. wt thallus for seven species of Ulva, and 82.5–95.4 × 106 cells g− 1 f. wt for three species of Enteromorpha. The regeneration rate of protoplasts isolated using this method ranged from 89 to 92% with normal morphogenesis. The seeding of nylon threads with isolated protoplasts of M. oxyspermum was successful and after 3–4 weeks the entire frame with nylon threads became thick green in color with tiny germlings in laboratory culture. Thus, the method described in the present study allow for rapid mass production of viable protoplasts that could be potentially used as a source for seed material for mariculture and for other applied phycological research. 相似文献
106.
A study was conducted to evaluate the effects of postpartum prostaglandin treatment on reproduction in 3 seasonal calving dairy herds. Recently calved lactating dairy cows were paired on herd, age, calving date and previous production index. One cow in each of the 196 pairs received a single intramuscular injection of 25 mg of the prostaglandin analogue, dinoprost, between 14 and 28 days after calving. Subsequent reproduction was monitored. Within each herd and overall, there was no significant effect of treatment on the intervals from calving to first service, mating start date to first service, calving to conception, mating start date to conception and first service to conception. Treatment also had no significant effect on 21-day submission and pregnancy rates, on the proportion of each group not pregnant at the end of mating, and on first service pregnancy rates. Responses to treatment did not vary between cows calving within 50 days of mating start date and earlier calving cows or between cows aged less than 5 years and older cows. 相似文献
107.
108.
A Junaidi PE Williamson GB Martin MA Blackberry JM Cummins TE Trigg 《Reproduction in domestic animals》2009,44(5):725-734
We tested the effect of dose of GnRH superagonist on pituitary and testicular function in a study with four groups of four male dogs. The Controls received blank implants and the other three groups received implants containing 3, 6 or 12 mg deslorelin (d ‐Trp6‐Pro9‐des‐Gly10‐GnRH ethylamide). In all deslorelin‐treated groups, there was initially an acute increase in plasma concentrations of LH and testosterone, followed by declines such that both hormones became undetectable after approximately 12 days. There was a dose–response in some of these early aspects of the hormone profiles. With respect to long‐term effects of treatment, the 12‐mg dose had significantly greater effects than the smaller doses for the duration of minimum testicular volume [366 ± 77, mean ± SEM (3 mg), 472 ± 74 (6 mg), and 634 ± 59 (12 mg) days], absence of ejaculate [416 ± 88 (3 mg), 476 ± 83 (6 mg), and 644 ± 67 (12 mg) days], undetectable plasma concentrations of LH and testosterone [367 ± 64 (3 mg), 419 ± 72 (6 mg), and 607 ± 69 (12 mg) days], the delay until complete recovery of LH and testosterone secretion [394 ± 65 (3 mg), 484 ± 72 (6 mg) and 668 ± 47 (12 mg) days], and the delay until testes had regrown to normal volume [408 ± 77 (3 mg), 514 ± 74 (6 mg), 676 ± 59 (12 mg) days]. The time taken to restore full ejaculates was also longest for the 12‐mg dose: 716 ± 67 (12 mg) days vs 440 ± 66 (3 mg) and 538 ± 83 (6 mg) days after implantation. There was no correlation between delay to recovery of normal ejaculate quality and body mass. We conclude that the dose–response relationship with deslorelin implants is not expressed with respect to the degree of suppression of reproduction, but on the maximum duration of suppression and thus to delay until recovery. 相似文献
109.
110.
Nature has been instrumental as a source for therapeutics. Despite the fact that we live in an oceanic planet, a number of technical factors have historically hampered the evolution of a marine-based chamanic medicine. With the implementation of scuba diving tools and the development of sophisticated instruments for the isolation and elucidation of structures of natural products from marine organisms, major advances have been made in the discovery of marine derived therapeutics. The availability of ARA-C, a nucleoside analog that is a basic component in the treatment of acute myeloid leukemia, and its fluorinated analog Gemcitabine, an important therapeutic tool in the treatment of pancreatic cancer and in non small cell lung cancer, is a solid proof and validation of the potential of this approach. As a result of our discovery and developmental program, three innovative compounds with novel mechanisms of action: ET-743, AplidinR and Kahalalide F, have been shown to display a positive therapeutic index and activity in resistant solid tumors that supports the ongoing clinical phase III/II trials. ET-743 represents the first active agent against sarcomas developed in the past 25 years and has demonstrated a therapeutic potential in pretreated ovarian cancer. Several chemical entities are under advanced preclinical testing and additional candidates for clinical development are emerging, including compounds hitting a specific target. Moreover, the development of a given marine candidate implies the collaboration of an interdisciplinary team special focused on supply, formulation, pharmacogenetics and preclinical toxicology. 相似文献