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81.
Deoxynivalenol (DON), a well-known contaminant of feed, can have negative effects on gut permeability and function in poultry, which then could affect major and trace element content of the broilers’ breast and thigh muscles, and ultimately reduce meat quality. To study this hypothesis, DON-contaminated diet was fed to broiler chicks. Two groups of birds were housed in metabolic cages with free access to water and feed, with or without DON (10 mg/kg). After 5 weeks, birds were dissected and samples of the breast and thigh muscles, feed and droppings were analysed for five macro (Ca, K, Mg, Na, and P) and ten micro elements (Al, Cr, Cu, Fe, Mn, Li, Mo, Ni, Pb, Rb, and Zn) by inductively coupled plasma optical emission spectrometry (ICP-OES) or inductively coupled plasma mass spectrometer (ICP-MS) methods. In both groups, increased (p?<?0.05) concentrations of Ca Na, Fe, Mn, and Zn were found in thigh muscles compared with the breast, whereas the concentrations of Mg, P, and Rb were higher in the breast muscles. DON had no effect on the elemental contents of the broilers’ breast and thigh muscles. In conclusion, DON at a level of 10 mg/kg feed to broiler chicken over of 5 weeks did not alter the macro or micro element composition in muscle meat.  相似文献   
82.
After a short introduction to the phenomena of children with Down's syndrome, values describing body status as gained by Schmid at the Aschaffenburg hospital for child disease (F.R.G.) are recalled. In a cross-sectional study values for body height, head circumference and body weight for 393 girls and 436 boys were gathered in 1983 reflecting the status for medically treated patients of the present. After insuring that the scattering of the data keeps within tolerable limits growth specific analysis became a challenge. Body length is approximated with the 2 step model by Sager (1981) comprising a basic function without a growth spurt superimposed by a spurt term. As a result, an usual but somewhat reduced growth spurt can be secured for the girls whilst the boys show no intermediate maximum in growth velocity. Nevertheless velocity keeps well above that for the basic function thus indicating a silent spurt after the definition of Pelez and Sager (1984). Head circumference too is treated with the same model after tests with Czech values for common and gypsy children. As a result, a reduced but acute growth spurt with a growth hump for the increase function has been found for both sexes. In contrast to height, however, a short term formula for values from birth to near pubescence cannot be applied due to the vivid head growth in the postnatal phase. Values for body weight W allow first conclusions after plotting log W against the body length L. In the case of the Down patients, 2 different forms of fundamental relations emerge, one of them related to normal growth, the other to impeded or less differentiated development as found in the rhesus for example. For both cases, mathematical expressions as proposed and used by Sager are applied. Results show near to normal behaviour for the girls and a less intricate course in weight growth for the boys. Results are given in graphs and tables allowing detailed calculations if desired. Quotients of momentary to finally attained values for body height and weight as well as head circumference are added.  相似文献   
83.
Areas of skin approximately 1.5 cm in diameter on the legs of mice were made hyperthermic (30 min at 42.7 degrees C) by exposure to an ultrasound beam (780 kHz), a single dose of X irradiation (2000 rad), or a combination of these treatments. After 35 days, when the acute reaction had reached a steady state, the same tissue was given a second treatment by either hyperthermia, irradiation, or a combination of hyperthermia and irradiation. When the first treatment was irradiation and the second treatment was either irradiation or a combination of hyperthermia and irradiation, the acute skin reactions were similar to those of skin not previously irradiated, indicating a large proportion of recovery from the first irradiation. When irradiation was the first treatment, a comparison of second treatments by hyperthermia plus irradiation with irradiation alone showed a thermal enhancement of 1.45. When the first treatment was hyperthermia plus irradiation, a comparison of second treatments by hyperthermia plus irradiation with irradiation also showed an enhancement factor of 1.45 for the combined treatment.  相似文献   
84.
ABSTRACT. Troglocorys cava n. g., n. sp. is described from the feces of wild eastern chimpanzee, Pan troglodytes schweinfurthii, in Uganda. This new species has a spherical body with a frontal lobe, a long vestibulum, a cytoproct located at the posterior dorsal side of the body, an ovoid macronucleus, a contractile vacuole near the cytoproct, and a large concavity on the left surface of the body. Buccal ciliature is non‐retractable and consists of three ciliary zones: an adoral zone surrounding the vestibular opening, a dorso‐adoral zone extending transversely at the basis of the frontal lobe, and a vestibular zone longitudinally extending in a gently spiral curve to line the surface of the vestibulum. Two non‐retractable somatic ciliary zones comprise arches over the body surface: a short dorsal ciliary arch extending transversely at the basis of the frontal lobe and a wide C‐shaped left ciliary arch in the left concavity. Because of the presence of three ciliary zones in the non‐retractable buccal ciliature, the present genus might be a member of the family Blepharocorythidae, but the large left concavity and the C‐shaped left ciliary arch are unique, such structures have never been described from other blepharocorythids.  相似文献   
85.
86.
Sager R  Ramanis Z 《Genetics》1976,83(2):303-321
This paper presents allelic segregation data from a series of 16 crosses segregated for nuclear and chloroplast genes. By means of pedigree analysis, segregants of chloroplast markers occurring in the zygote have been distinguished from those occurring in zoospore clones. The genes ac1, ac2, and tm1 showed little if any deviation from 1:1 either in zygotic segregation or in zoospore clones. The genes sm2, ery, and spc showed a significant excess of the allele from the mt (+) parent in zygotes. However, in zoospores, mt( +) excess was seen only when that allele was the mutant (resistant) form but not when it was wild type (sensitive).These results show that the extent of preferential segregation differs in zygotes and in zoospores, and that preferential segregation is influenced by map location and by allele specificity. A comparison of progeny from zygotes mated after 0, 15', 30', and 50' UV irradiation of the mt(+) gametes demonstrated the lack of an effect of UV upon allelic segregation ratios. In total, these results exclude the multi-copy model of chloroplast genome segregation suggested by Gillham, Boynton and Lee (1974) and support the diploid model we have previously proposed (Sager and Ramanis 1968, 1970; Sager 1972).  相似文献   
87.
Using environmental parameters we studied the distribution of two endangered species, Hydrocharis morsus-ranae L. and Rumex hydrolapathum Huds., in a low-lying marshland of the Swiss Plateau, a region in which aquatic vegetation is particularly threatened. A large part of the study site is regularly mown by a machine for site management purposes. The caterpillar mower digs ruts, which are especially pronounced along the tracks used to reach the mown compartment. To assess the effects of site management on these species, we have tested six environmental parameters (vegetation unit, water conductivity, water supply indicated by altitude, time elapsed since the last cut, distance from major ruts and disturbance of major ruts) that can potentially influence plant distribution. All the plots of these two species have been found in mowed compartment, which seems to indicate a correlation between site management operations and occurrences. The other factors driving the distribution of these plants are vegetation unit, distance from major ruts and water supply.  相似文献   
88.
Potato and wheat plants were grown for 50 d at 400, 1000 and 10000 micromoles mol-1 carbon dioxide (CO2). and sweetpotato and soybean were grown at 1000 micromoles mol-1 CO2 in controlled environment chambers to study stomatal conductance and plant water use. Lighting was provided with fluorescent lamps as a 12 h photoperiod with 300 micromoles m-2 s-1 PAR. Mid-day stomatal conductances for potato were greatest at 400 and 10000 micromoles mol-1 and least at 1000 micromoles mol-1 CO2. Mid-day conductances for wheat were greatest at 400 micromoles mol-1 and least at 1000 and 10000 micromoles mol-1 CO2. Mid-dark period conductances for potato were significantly greater at 10000 micromoles mol-1 than at 400 or 1000 micromoles mol-1, whereas dark conductance for wheat was similar in all CO2 treatments. Temporarily changing the CO2 concentration from the native 1000 micromoles mol-1 to 400 micromoles mol-1 increased mid-day conductance for all species, while temporarily changing from 1000 to 10000 micromoles mol-1 also increased conductance for potato and sweetpotato. Temporarily changing the dark period CO2 from 1000 to 10000 micromoles mol-1 increased conductance for potato, soybean and sweetpotato. In all cases, the stomatal responses were reversible, i.e. conductances returned to original rates following temporary changes in CO2 concentration. Canopy water use for potato was greatest at 10000, intermediate at 400, and least at 1000 micromoles mol-1 CO2, whereas canopy water use for wheat was greatest at 400 and similar at 1000 and 10000 micromoles mol-1 CO2. Elevated CO2 treatments (i.e. 1000 and 10000 micromoles mol-1) resulted in increased plant biomass for both wheat and potato relative to 400 micromoles mol-1, and no injurious effects were apparent from the 10000 micromoles mol-1 treatment. Results indicate that super-elevated CO2 (i.e. 10000 micromoles mol-1) can increase stomatal conductance in some species, particularly during the dark period, resulting in increased water use and decreased water use efficiency.  相似文献   
89.
Sager JJ  Torres GE 《Biochemistry》2011,50(34):7295-7310
Plasma membrane and vesicular transporters for the biogenic amines, dopamine, norepinephrine, and serotonin, represent a group of proteins that play a crucial role in the regulation of neurotransmission. Clinically, mono amine transporters are the primary targets for the actions of many therapeutic agents used to treat mood disorders, as well as the site of action for highly addictive psychostimulants such as cocaine, amphetamine, methamphetamine, and 3,4-methylenedioxymethamphetamine. Over the past decade, the use of approaches such as yeast two-hybrid and proteomics has identified a multitude of transporter interacting proteins, suggesting that the function and regulation of these transporters are more complex than previously anticipated. With the increasing number of interacting proteins, the rules dictating transporter synthesis, assembly, targeting, trafficking, and function are beginning to be deciphered. Although many of these protein interactions have yet to be fully characterized, current knowledge is beginning to shed light on novel transporter mechanisms involved in monoamine homeostasis, the molecular actions of psychostimulants, and potential disease mechanisms. While future studies resolving the spatial and temporal resolution of these, and yet unknown, interactions will be needed, the realization that monoamine transporters do not work alone opens the path to a plethora of possible pharmacological interventions.  相似文献   
90.

Introduction

Increased frequencies of hyperuricemia and gout have been associated with primary hyperparathyroidism, and recent clinical trials of parathyroid hormone (PTH) have reported hyperuricemic adverse events. We evaluated the potential population impact of PTH on serum uric acid (SUA) levels by using a nationally representative sample of United States adults.

Methods

By using data from 8,316 participants aged 18 years and older in the National Health and Nutrition Examination Survey 2003 to 2006, we examined the relation between serum PTH and SUA levels with weighted linear regression. Additionally, we examined the relation with hyperuricemia by using weighted logistic regression.

Results

SUA levels increased with increasing serum PTH concentration. After adjusting for age, sex, dietary factors, glomerular filtration rate (GFR), and other potentially related biomarkers (calcium, phosphorus, alkaline-phosphatase, 25-hydroxyvitamin D), the SUA level differences from the bottom (referent) to top quintiles of serum PTH levels were 0, 8, 13, 14, and 19 ??M (95% CI, 12 to 26; P for trend, < 0.001). These estimates were larger among renally impaired individuals (multivariate SUA difference between the extreme quintiles of PTH, 26 versus 15 ??M among those with GFR ?? 60 versus < 60 ml/min per 1.73 m2, respectively) (P for interaction = 0.004). The odds of hyperuricemia by various definitions increased with increasing PTH levels as well (multivariate P values for trend, < 0.05).

Conclusions

These nationally representative data indicate that serum PTH levels are independently associated with serum uric acid levels and the frequency of hyperuricemia at the population level.  相似文献   
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