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111.
The global endemic of cardiovascular diseases calls for improved risk assessment and treatment. Here, we describe an association between myocardial infarction (MI) and a common sequence variant on chromosome 9p21. This study included a total of 4587 cases and 12,767 controls. The identified variant, adjacent to the tumor suppressor genes CDKN2A and CDKN2B, was associated with the disease with high significance. Approximately 21% of individuals in the population are homozygous for this variant, and their estimated risk of suffering myocardial infarction is 1.64 times as great as that of noncarriers. The corresponding risk is 2.02 times as great for early-onset cases. The population attributable risk is 21% for MI in general and 31% for early-onset cases.  相似文献   
112.
Triclinic ulexite crystals contain isolated borate polyanions [B(5)O(6)(OH)(6)](3-) related to the well known pentaborate polyanion [B(5)O(6)(OH)(4)](-) by addition of two hydroxyl groups to two opposite B-O triangles. The isolated ulexite polyanions form the [B(5)O(7)(OH)(4)](n)(3n-) chains previously found in crystals of the related mineral probertite, NaCaB(5)O(7)(OH)(4).3H(2)O.  相似文献   
113.
Plants of three cultivars of lucerne ( Medicago sativa L.) and of red clover ( Trifolium pratense L.) were grown at four levels each of water availability and temperature in all combinations to evaluate these factors as determinants of plant growth. Plants grew in conventional plant growth chambers from age 2 to 4 weeks with the roots held between layers of polyester cloths that held a volume of nutrient solution which was adjusted at 24-h intervals by flushing and blotting the cloths. The experimental design consisted of two growth chamber runs at each of four temperatures. Within each run, water treatments and the species-cultivar combination were arranged In four replicates of a split-plot design with water treatment as whole plot and species-cultivars as subplots.
Plant response variables over all treatments were significant (P < 0·05) for temperature and water for shoot weights, root weights, shoot/root ratios and number of roots. Cultivars within species had no significant difference in response lo the treatments, but species differences were significant for alt response variables except shoot/root ratio.  相似文献   
114.
The most common pathological anovulatory condition that occurs spontaneously during the breeding season in the mare is the haemorrhagic anovulatory follicle (HAF). A relatively high proportion of mares, soon after ovulation, develop a corpus haemorrhagicum (CH) with a central lacuna. This type of corpora lutea may resemble an HAF, which may complicate the accurate diagnosis of ovulation. The main objective of this study was to compare the ultrasound data of mares examined frequently with HAFs and CHs to elucidate whether it is possible to distinguish them from each other. A total of 135 ovulating mares were classified according to the morphology of the corpus luteum (CL) in mares with: a solid CL, a CH with small or with large central cavities. Ultrasound characteristics of the development of 11 HAF and 13 CHs with a large central cavity were compared. The pre‐ovulatory follicular diameter of ovulatory mares was significantly correlated with the diameter of CH with large central cavities. The percentage of mares with post‐ovulatory areas eligible to be mistaken with a CH was <25%. Although a predictive diagnosis of an HAF/CH can be made on the basis of several ultrasonographic endpoints, the only parameter that allows a definitive diagnosis is the thickness of the luteal border. This is <3 mm in HAFs in contrast to >5 mm in CHs. However, this only applies when the unidentified structure has non‐organized contents.  相似文献   
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Based on work largely in laboratory animals, transforming growth factors (TGF) and insulin like growth factors (IGF) could be regulators of testicular development. The aim of this study was to see if TGF‐alpha and ‐beta 1, 2 and 3 are present in the bovine testis and to monitor concentrations of these factors in the testis and IGF‐I in serum during reproductive development. Separate groups of Hereford × Charolais calves (n = 6) were castrated every 4 weeks from 5 to 33 weeks of age and at 56 weeks of age. A week prior to castration, from 5 to 33 weeks of age, blood was collected every 15 min for 10 h. Serum IGF‐I concentrations increased from 8 to 12 weeks of age, decreased from 24 to 28 weeks and increased to 32 weeks of age (p < 0.05). Testicular TGF‐alpha concentrations increased from 13 to 17 weeks of age, decreased to 21 weeks and from 33 to 56 weeks of age (p < 0.05). Testicular TGF‐beta 1 concentrations decreased from 17 to 21 weeks of age, increased to 25 weeks and decreased from 25 to 33 weeks of age (p < 0.05). Testicular TGF‐beta 2 concentrations increased from 5 to 17 weeks of age, decreased to 21 weeks, increased to 25 weeks and decreased at 29 weeks of age (p < 0.05). Testicular TGF‐beta 3 concentrations increased from 13 to 17 weeks of age, decreased to 21 weeks and from 25 to 29 weeks of age (p < 0.05). We concluded that TGF‐alpha and TGF‐beta 1, 2 and 3 are present in the testis of the bull calf, and changes in concentrations with age suggest a functional role in the development of the testis.  相似文献   
118.
Based on observations in laboratory animals interleukins could be regulators of testicular development. The objects of this study were to see if interleukins (IL‐1 and IL‐6) are present in the developing bull testis and to establish the temporal patterns of concentrations of IL‐1 and IL‐6 in the bovine testis during development. Separate groups of six bull calves were castrated every 4 weeks from 5 to 33 weeks of age, and at 56 weeks of age. Mean testicular IL‐1 alpha concentrations decreased (p < 0.01) from 5 to 9 weeks of age and 13 to 21 weeks of age. Mean testicular IL‐1 beta concentrations decreased (p < 0.01) from 13 to 17 weeks of age and from 29 to 33 weeks of age. Mean IL‐1 bioactivity increased from 13 to 17 weeks of age, decreased to 21 weeks, increased to 25 weeks, decreased to 29 weeks and decreased from 33 to 56 weeks of age (p < 0.05). Mean testicular IL‐6 concentrations decreased (p < 0.05) from 9 to 13 weeks of age, increased (p < 0.05) to 21 weeks, decreased (p < 0.05) to 25 weeks, increased (p < 0.05) to 29 weeks and decreased (p < 0.01) to 56 weeks of age. In conclusion, testicular IL‐1 alpha, IL‐1 beta and IL‐6 were found in the bovine testis and concentrations were age dependent. Testicular IL‐1 alpha and IL‐1 beta concentrations were highest in the early post‐natal period; however, IL‐1 bioactivity and IL‐6 concentrations were greatest in the immediate pre‐pubertal period. These findings suggest a functional role for interleukins in testicular development in the bull.  相似文献   
119.
Objectives To define the prevalence of Bartonella spp., Rickettsia felis, Mycoplasma haemofelis, ‘Candidatus Mycoplasma haemominutum’ (Mhm) and ‘Candidatus Mycoplasma turicensis’ (Mtc) in cats and their fleas in eastern Australia. Design and procedure Conventional PCR assays that detect Bartonella spp., M. haemofelis, Mhm, Mtc, Rickettsia spp., Ehrlichia spp., Anaplasma spp. and Neorickettsia spp. were performed on DNA extracted from blood and fleas collected from 111 cats. Cat sera were assayed by ELISA for IgG of Bartonella spp. Results DNA of M. haemofelis, Mtc and Mhm was amplified from 1 (0.9%), 1 (0.9%) and 17 cats (15.3%), respectively. Only DNA of Mhm was amplified from the 62 of 111 pooled flea samples (flea sets; 55.9%). Overall, the prevalence rates for Bartonella spp. DNA in the cats and the flea sets was 16.2% (18 cats) and 28.8% (32 flea sets), respectively. Bartonella spp. IgG was detected in 42 cats (37.8%), of which 11 (26.2%) were positive for Bartonella spp. DNA in their blood. R. felis DNA was amplified from 22 flea sets (19.8%), but not from cats. Overall, DNA of one or more of the organisms was amplified from 27% (30) of cats and 67.6% (75) of the flea sets. Conclusions This is the first Australian study to determine the prevalence of R. felis and B. clarridgeiae in both fleas and the cats from which they were collected. Flea-associated infectious agents are common in cats and fleas in eastern Australia and support the recommendation that stringent flea control be maintained on cats.  相似文献   
120.
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