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81.
In the “Eastern Pontides” (NE Turkey), the intense volcanic activity accompanying carbonate-siliceous sedimentation during the Late Cretaceous period ensured the occurrence of thick volcano-sedimentary sequences. Seventy-one radiolarian species belonging to 26 genera were identified from five stratigraphic sections of the Upper Cretaceous sequences between Trabzon and Giresun areas in NE Turkey. These species were obtained from the lower Turonian–lower Coniacian strata of the Çe?meler Formation, the Coniacian–lower Santonian strata of the Elmal? Dere Formation and the upper Santonian strata of the Ça?layan Formation. Coniacian–Campanian fauna, consisting of planktonic foraminifera Hedbergella, Marginotruncana, Globotruncana, Whiteinella and biserial heterohelicids as well as radiolarians, was recovered from the red pelagic limestones of the Elmal? Dere Formation known as marker horizon.  相似文献   
82.
Vitamin requirements, determined by two different methods, and other nutritional characteristics of 46 psychrophobic and 30 non-psychrophobic yeasts were investigated. Vitamin requirements and induced nutritional imbalances emerged as criteria for definingCandida slooffii. Strains of this species behaved uniformly. Variations in vitamin requirements of strains ofSaccharomyces telluris, Torulopsis bovina andTorulopsis pintolopesii were confirmed. The choline requirement exhibited by several strains (by as many as 86% inS. telluris) was evident on a simple defined medium without methionine, but not on Wickerham's vitamin-free basal medium. The group of choline-requiring strains comprised strains responding similarly to choline or methionine, and some strains growing with choline but not with methionine on short incubation. Other frequently required vitamins were biotin, pantothenate, thiamine, nicotinic acid, pyridoxine, and inositol. Fellow of the John Simon Guggenheim Memorial Foundation. Fellow of the National Research Council (Brasil).  相似文献   
83.
84.
Whooping cough (pertussis) is a highly contagious respiratory infection caused by Bordetella pertussis. Although availability of effective pertussis vaccines reportedly decreases the incidence of the disease, B. pertussis circulation in populations has not been eliminated. Thus, it is necessary to find new protein candidates with greater immune protective capacities than the currently available acellular pertussis vaccines. In this study, iron superoxide dismutase (FeSOD) gene (sodB) was cloned, expressed in Escherichia coli and recombinant FeSOD protein thence purified. The recombinant protein (rFeSOD) was formulated with aluminum hydroxide (Alum) or monophosphoryl lipid A (MPLA) and injected intraperitoneally to immunize mice, after which IgG1, IgG2a and IFN‐γ titers were measured to assess humoral and cellular responses, respectively, to these immunizations. The extent of bacterial colonization in lungs of intranasally challenged mice was determined 5, 8 and 14 days post‐challenge. IgG1 and IgG2a responses were significantly stronger in mice that had been immunized with rFeSOD–MPLA than in those that had received rFeSOD‐Alum (P < 0.05). Additionally, IgG2a titers were higher in mice vaccinated with recombinant protein FeSOD (rFeSOD) formulated with MPLA, especially after the second immunization. Immunization with rFeSOD–MPLA also provided a modest, but significant decrease in bacterial counts in lungs of mice (P < 0.05). Antigen specific‐IFN‐γ responses were significantly stronger in the group vaccinated with rFeSOD–MPLA, which could account for the lower bacterial counts. These findings suggest that rFeSOD protein formulated with MPLA has potential as an acellular pertussis vaccine candidate component.  相似文献   
85.
Experimental design is a form of process analysis in which certain factors are selected to obtain the desired responses of interest. It may also be used for the determination of the effects of various independent factors on a dependent factor. The bioengineering discipline includes many different areas of scientific interest, and each study area is affected and governed by many different factors. Briefly analyzing the important factors and selecting an experimental design for optimization are very effective tools for the design of any bioprocess under question. This review summarizes experimental design methods that can be used to investigate various factors relating to bioengineering processes. The experimental methods generally used in bioengineering are as follows: full factorial design, fractional factorial design, Plackett–Burman design, Taguchi design, Box–Behnken design and central composite design. These design methods are briefly introduced, and then the application of these design methods to study different bioengineering processes is analyzed.  相似文献   
86.
Cisplatin (CP) treatment causes the damage in male reproductive system. Carvacrol (CARV) is an antioxidant that is naturally found in some plants. We aimed to investigate the effect of CARV on CP‐induced reproductive toxicity in male rats. Eighteen adult male Sprague–Dawley rats were used. The control group (n = 6) was treated orally with physiological saline (PS) daily for 14 days and a single intraperitoneal (IP) PS injection on day 10. The CP group (n = 6) was administered with daily oral PS for 14 days and a single IP injection of 10 mg/kg CP on day 10. The CARV + CP group (n = 6) was treated with daily 75 mg/kg oral CARV for 14 days and a single IP injection of 10 mg/kg CP on day 10. CP treatment caused the damage on some spermatological parameters (motility, live sperm rate, and abnormal sperm rate), increased the oxidative stress, and induced testicular degeneration and apoptosis. However, CARV treatment mitigates CP‐induced reproductive toxicity.  相似文献   
87.
The activity concentrations of radionuclides in grape molasses soil samples collected from Zile (Tokat) plain in the Central Black Sea region of Turkey were measured by using gamma spectrometer with a NaI(Tl) detector. Also, the concentrations of 222Rn in soil samples and air were estimated essentially taking the activity concentrations of 226Ra measured in soil samples. Grape molasses soil samples with calcium carbonate content are used for sedimentation for making molasses in this region. The average activity concentrations of 232Th, 226Ra, 40K, and 137Cs were found as 62 ± 2, 68 ± 3, 479 ± 35, and 8.0 ± 0.3 Bq kg?1, respectively. The average concentrations of 222Rn in soil samples and air were estimated to be 50 kBq m?3 and 144 Bq m?3. From the activity concentrations, absorbed gamma dose rate in outdoor air (D), annual effective dose from external exposure (EE), annual effective dose from inhalation of radon (EI), and excess lifetime cancer risk (ELCR) were estimated in order to assess radiological risks. The average values of D, EE, EI, and ELCR were found to be 90 nGy h?1, 110 μSv y?1, 1360 μSv y?1, and 4 × 10?4, respectively.  相似文献   
88.
89.
The Lutzomyia subgenus (Diptera: Psychodidae) includes sibling species with morphologically indistinguishable females. The aims of this study were to analyse variations in the size and shape of wings of species within the Lutzomyia subgenus and to assess whether these analyses might be useful in their identification. Wings (n = 733) of 18 species deposited in Brazilian collections were analysed by geometric morphometrics, using other genera and subgenera as outgroups. Shape variation was summarized in multivariate analyses and differences in wing size among species were tested by analysis of variance. The results showed significant variation in the sizes and shapes of wings of different Lutzomyia species. Two clusters within the Lutzomyia subgenus were distinguished in analyses of both males and females. In Cluster 1 (Lutzomyia ischnacantha, Lutzomyia cavernicola, Lutzomyia almerioi, Lutzomyia forattinii, Lutzomyia renei and Lutzomyia battistinii), scores for correct reclassification were high (females, kappa = 0.91; males, kappa = 0.90), whereas in Cluster 2 (Lutzomyia alencari, Lutzomyia ischyracantha, Lutzomyia cruzi, Lutzomyia longipalpis, Lutzomyia gaminarai and Lutzomyia lichyi), scores for correct reclassification were low (females, kappa = 0.42; males, kappa = 0.48). Wing geometry was useful in the identification of some species of the Lutzomyia subgenus, but did not allow the identification of sibling species such as L. longipalpis and L. cruzi.  相似文献   
90.
In this study, we aimed to detect the proportion of Candida dubliniensis among yeast strains previously identified as C. albicans by using several phenotypic methods and PCR. For this purpose, we screened 300 strains by using phenotypic tests suggested for the identification of C. dubliniensis in the literature, but we detected high proportion of false-positive reactions. Only two strains (0.6%) were detected as true C. dubliniensis by PCR and API ID 32C methods. Moreover, these two strains gave the expected results with all the phenotypic tests, including modified salt tolerance test for C. dubliniensis. In conclusion, none of the phenotypic methods, except for the modified salt tolerance test, revealed 100% successful results in discrimination of C. albicans and C. dubliniensis species. However, in the tobacco agar test, the rate of false positivity was as low as 0.6%. We suggest that in the case of absence of PCR and other automatized identification systems, these two phenotypic tests can be used in routine laboratories to obtain a presumptive result.  相似文献   
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