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1.
Maria João Feio Trefor B. Reynoldson Verónica Ferreira Manuel Augusto S. Graça 《Hydrobiologia》2007,579(1):55-68
We sampled macroinvertebrates at 75 locations in the Mondego river catchment, Central Portugal, and developed a predictive
model for water quality assessment of this basin, based on the Reference Condition Approach. Sampling was done from June to
September 2001. Fifty-five sites were identified as “Reference sites” and 20 sites were used as “Test sites” to test the model.
At each site we also measured 40 habitat variables to characterize water physics and chemistry, habitat type, land use, stream
hydrology and geographic location. Macroinvertebrates were generally identified to species or genus level; a total of 207
taxa were found. By Unweighted Pair Group Method with Arithmetic mean (UPGMA) clustering and analysis of species contribution
to similarities percentage (SIMPER), two groups of reference sites were established. Using Discriminant Analysis (stepwise
forward), four variables correctly predicted 78% of the reference sites to the appropriate group: stream order, pool quality,
substrate quality and current velocity. Test sites’ environmental quality was established from their relative distance to
reference sites, in MDS ordination space, using a series of bands (BEAST methodology). The model performed well at upstream
sites, but at downstream sites it was compromised by the lack of reference sites. As with the English RIVPACS predictive model,
the Mondego model should be continually improved with the addition of new reference sites. The adaptation of the Mondego model
methodology to the Water Framework Directive is possible and would consist mainly of the integration of the WFD typology and
increasing the number of ellipses that define quality bands.
Handling editor: K. Martens 相似文献
2.
3.
Summary The child with iminoglycinuria is in our observation. Hyperprolinuria was seen at 5 months by screening program. The child was repeatedly examined in the hospital and was seen last time at 16 months. IQ was 67, in the urine were excessive amounts of glycine, proline a hydroxyproline. In the blood aminoacids were in normal levels. In the child was noticed the same increase of proline in the blood as in the control child of the same age following loading test with L-proline, indicating normal intestinal absoption. Both parents and father's sister's 2-year-old mentally retarded child exhibit excessive glycinuria. The father, his sister, father's father, and grandfather are partialy, congenitaly deaf. 相似文献
4.
5.
6.
Elžbieta Milewska-Pawliczuk 《Biologia Plantarum》1987,29(4):295-298
Six thousand anthers ofSecale cereale cv. Dańkowskie Zlote and inbred lines L214 L215 and L258c/5, in the uninuclear microspore were cultured over a period of
three months on Murashige and Skoog nutrient medium supplemented with IAA (1–2μg1−1), kinetin (0.2 to (1.0μg1−1) and 2,4-D (0.5–2.0μg1−1). First divisions of microspore were observed after 7 days. In the course of 10 weeks, 4 albino tic embryos at the cotyledon
stage were observed that died away in the course of further culture. The course of androgenesis was regular in inbred lines
and irregular in rye cv. Dańkowskie Ziote. The efficiency of androgenesis and the amount of observed globular structures in
anthers were also dependent on the genetic potency of the material. Inbred lines did not show any greater viability of embryos. 相似文献
7.
The effect of tin and lead on levels of essential metals (Zn, Cu, Ca, Fe) in rabbit tissues was compared in relation to the route of administration. Animals received intraperitoneally, or per os, SnCl2 (2 mg Sn/kg) or Pb(CH3COO)2 (3.5 mg Pb/kg) every day for 5 d or for 1 mo. Copper, zinc, iron, and calcium were determined by AAS in the liver, kidneys, spleen, brain, bone marrow, and blood; lead and tin concentration were measured in the blood of animals. Tin and lead administered per os caused either no changes or the decreased concentration of endogenous metals in several tissues. The other route of administration (ip) of both metals generally contributed to the increased storage of essential elements. Blood tin levels of tin treated animals were only about less than or equal to 1/10 of blood lead concentrations of rabbits exposed to lead. 相似文献
8.
Miroslav Flieger Jaroslav Votruba Vladimír Křen Sylvie Pažoutová Viktor Rylko Přemysl Sajdl Zdeněk Reháček 《Applied microbiology and biotechnology》1988,29(2-3):181-185
Summary Kinetic parameters of production of clavine alkaloids were evaluated in twoClaviceps purpurea strains. Mutagenesis brought about enhanced resistance of the biosynthetic system towards alkaloids. Addition of glucose into the fermentation medium altered the zero order kinetics of production to activation-inhibition kinetics. The glucose treatment allowed performance of both elymoclavine-inhibitionless and clavine alkaloid-decompositionless fermentations if a combination of fermentation and separation units in a closed loop was used.Nomenlacture
k
1
rate constant of agroclavine synthesis (mg Agro · mg Elymo/l·g DW·day for stage 1, mg Agro/g DW·day for stage 2)
-
k
2
parameter describing inhibition of agroclavine formation rate by elymoclavine (mg Elymo/l)
-
k
3
specific rate of agroclavine decay (l/g DW·day)
-
k
4
maximal specific rate of elymoclavine synthesis (stage 1, 1/g DW·day, stage 2, mg Elymo/g DW·day)
-
k
4
–
maximal specific rate of elymoclavine synthesis in stage 1 (inhibition-activation mechanism) (mg Elymo/g DW·day)
-
k
5
physiological constant describing the elymoclavine decay rate (l2/g DW·day·mg Elymo)
-
k
5
–
physiological constant describing the activation of elymoclavine biosynthesis by elymoclavine (mg Elymo/l)
-
k
6
physiological constant describing the repression of elymoclavine biosynthesis by elymoclavine (mg Elymo/l)
-
k
7
maximal specific growth rate (1/day)
-
k
8
specific rate of biomass decay (l/g DW·day)
-
A
agroclavine concentration (mg/l)
-
E
elymoclavine concentration (mg/l)
-
r
A
specific rate of agroclavine biosynthesis (mg Agro/g DW·day)
-
r
E
specific rate of elymoclavine biosynthesis (mg Elymo/g DW·day)
-
r
i
specific rate of alkaloid biosynthesis (mg alkaloid/g DW·day)
-
X
dry biomass concentration (g/l)
-
specific growth rate (1/day)
Abbreviations Agro
agroclavine
- Elymo
elymoclavine
- Chano
chanoclavine
- DW
dry weight of biomass 相似文献
9.
J. Šťovíčková J. Turková B. Urbánek V. Bažant J. Kavalírová 《Biotechnology Techniques》1988,2(2):121-126
Summary The effect was studied of the method of drying chymotrypsin attached to bead cellulose on its chemical and physical characteristics. These characteristics are not deteriorated when replacing the commonly used lyophilisation by fluid drying in the air stream. The preparations saved essentially the same proteolytic activity as well as stability even when increasing the drying air temperature to 70°C. 相似文献
10.
G. Egea J. M. Ureña X. Graña J. Marsal J. Carreras F. Climent 《Histochemistry and cell biology》1992,97(3):269-275
Summary We have previously reported (Ureña et al. Eur. J. Cell Biol. 1990) that in skeletal muscle, type MM phosphoglycerate mutase isozyme is present in the nucleus as well as in the cytosol. To determine whether type BB phosphoglycerate mutase isozyme is also present in nucleus, the subcellular location of this isozyme was studied in different rat tissues by cell fractionation and immunogold techniques. With the aid of high affinity-purified anti-phosphoglycerate mutase BB isozyme antibodies, the isozyme was located in the nucleus of neuronal, astroglial and liver cells but not in the nucleus of oligodendroglial and endothelial cells. Biochemical studies on purified nuclear fractions also demonstrated the presence of phosphoglycerate mutase activity in the nucleus. Both immunocytochemical and biochemical techniques showed that nuclear phosphoglycerate mutase-specific activity depended on the type of cell.Abbreviations PGAM
phosphoglycerate mutase
- PGAM-M(M)
muscle specific subunit (isozyme) of PGAM
- PGAM-B(B)
brain type subunit (isozyme) of PGAM
- ssDNA
single stranded DNA
- PBS
0.001 M phosphate buffer, pH 7.4, containing 0.15 M NaCl
- kDa
kilodalton 相似文献