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71.
Piotrowski P Lianeri M Wudarski M Olesińska M Jagodziński PP 《Molecular biology reports》2012,39(9):8861-8866
The STAT4 has been found to be a susceptible gene in the development of systemic lupus erythematosus (SLE) in various populations. There are evident population differences in the context of clinical manifestations of SLE, therefore we investigated the prevalence of the STAT4 G > C (rs7582694) polymorphism in patients with SLE (n = 253) and controls (n = 521) in a sample of the Polish population. We found that patients with the STAT4 C/G and CC genotypes exhibited a 1.583-fold increased risk of SLE incidence (95 % CI = 1.168-2.145, p = 0.003), with OR for the C/C versus C/G and G/G genotypes was 1.967 (95 % CI = 1.152-3.358, p = 0.0119). The OR for the STAT4 C allele frequency showed a 1.539-fold increased risk of SLE (95 % CI = 1.209-1.959, p = 0.0004). We also observed an increased frequency of STAT4 C/C and C/G genotypes in SLE patients with renal symptoms OR = 2.259 (1.365-3.738, p = 0.0014), (p (corr) = 0.0238) and in SLE patients with neurologic manifestations OR = 2.867 (1.467-5.604, p = 0.0016), (p (corr) = 0.0272). Moreover, we found a contribution of STAT4 C/C and C/G genotypes to the presence of the anti-snRNP Ab OR = 3.237 (1.667-6.288, p = 0.0003), (p (corr) = 0.0051) and the presence of the anti-Scl-70 Ab OR = 2.665 (1.380-5.147, p = 0.0028), (p (corr) = 0.0476). Our studies confirmed an association of the STAT4 C (rs7582694) variant with the development of SLE and occurrence of some clinical manifestations of the disease. 相似文献
72.
Janowska B Kurpios-Piec D Prorok P Szparecki G Komisarski M Kowalczyk P Janion C Tudek B 《Mutation research》2012,729(1-2):41-51
One of the major lipid peroxidation products trans-4-hydroxy-2-nonenal (HNE), forms cyclic propano- or ethenoadducts bearing six- or seven-carbon atom side chains to G > C ? A > T. To specify the role of SOS DNA polymerases in HNE-induced mutations, we tested survival and mutation spectra in the lacZα gene of M13mp18 phage, whose DNA was treated in vitro with HNE, and which was grown in uvrA? Escherichia coli strains, carrying one, two or all three SOS DNA polymerases. When Pol IV was the only DNA SOS polymerase in the bacterial host, survival of HNE-treated M13 DNA was similar to, but mutation frequency was lower than in the strain containing all SOS DNA polymerases. When only Pol II or Pol V were present in host bacteria, phage survival decreased dramatically. Simultaneously, mutation frequency was substantially increased, but exclusively in the strain carrying only Pol V, suggesting that induction of mutations by HNE is mainly dependent on Pol V. To determine the role of Pol II and Pol IV in HNE induced mutagenesis, Pol II or Pol IV were expressed together with Pol V. This resulted in decrease of mutation frequency, suggesting that both enzymes can compete with Pol V, and bypass HNE-DNA adducts in an error-free manner. However, HNE-DNA adducts were easily bypassed by Pol IV and only infrequently by Pol II.Mutation spectrum established for strains expressing only Pol V, showed that in uvrA? bacteria the frequency of base substitutions and recombination increased in relation to NER proficient strains, particularly mutations at adenine sites. Among base substitutions A:T → C:G, A:T → G:C, G:C → A:T and G:C → T:A prevailed.The results suggest that Pol V can infrequently bypass HNE-DNA adducts inducing mutations at G, C and A sites, while bypass by Pol IV and Pol II is error-free, but for Pol II infrequent. 相似文献
73.
Plants have developed a range of strategies for resisting environmental stresses. One of the most common is the synthesis
and deposition of callose, which functions as a barrier against stress factor penetration. The aim of our study was to examine
whether callose forms an efficient barrier against Pb penetration in the roots of Lemna minor L. exposed to this metal. The obtained results showed that Pb induced callose synthesis in L. minor roots, but it was not deposited regularly in all tissues and cells. Callose occurred mainly in the protoderm and in the centre
of the root tip (procambial central cylinder). Moreover, continuous callose bands, which could form an efficient barrier for
Pb penetration, were formed only in the newly formed and anticlinal cell walls (CWs); while in other CWs, callose formed only
small clusters or incomplete bands. Such an arrangement of callose within root CWs inefficiently protected the protoplast
from Pb penetration. As a result, Pb was commonly present inside the root cells. In the light of the results, the barrier
role of callose against metal ion penetration appears to be less obvious than previously believed. It was indicated that induction
of callose synthesis is not enough for a successful blockade of the stress factor penetration. Furthermore, it would appear
that the pattern of callose distribution has an important role in this defence strategy. 相似文献
74.
It is commonly assumed that transformations of endosymbionts into organelles are exceptionally rare evolutionary events because of hypothetical difficulties in the origin of an import apparatus for nuclear-encoded, organelle-targeted proteins along with their targeting signals. A challenge to this view comes from recent studies of protein import into the cyanobacterial endosymbionts/organelles of Paulinella chromatophora. 相似文献
75.
Andrzej Wuczyński Bartosz Smyk Paweł Kołodziejczyk Wiesław Lenkiewicz Grzegorz Orłowski Andrzej Pola 《Central European Journal of Biology》2012,7(3):495-506
South-western Poland belongs to the key staging areas for geese in Europe, supporting some 100000 birds in recent years. We
compared goose counts conducted in the 1970s, 1990s and during 2009–2011 in this region, and linked the findings to the recent
assessments of trends in the flyway-populations. Numbers increased several dozen times between the first two counts and have
stabilized to the present. More than 14% of the flyway Tundra Bean Goose (Anser fabalis rossicus) stopped over in SW Poland on passage. Smaller numbers of White-fronted Goose (A. albifrons), Greylag Goose (A. anser), and four other rarer species, have all increased since the 1970s. The likely factors responsible for these changes are
mild weather conditions, increased availability of large water bodies and shifts in winter ranges of particular species. Temporal
mismatch between SW Poland and the total flyways in Bean and White-fronted Geese was recorded when we compared the long-term
and the short-term population trends. Increasing reports of other species in SW Poland match the general tendencies in Europe.
These data document that regional trends are not a simple reflection of those in flyways as a whole. To understand changes
in goose populations a re-established international count network is desired. 相似文献
76.
Ewa M. Skibniewska Michał Skibniewski Tadeusz Kosla 《Central European Journal of Biology》2012,7(5):817-824
The aim of the investigations was the determination of the Cu contents in the liver, kidneys and skeletal muscles of canine females. Material for research was collected post mortem from 45 animals aged 1 to 18 years coming from the Warsaw area. The effect of the health state, age and life conditions on the distribution of copper in the investigated organs was estimated. That element was determined using the method of inductively coupled plasma-atomic emission spectrometry (ICP-AES). In the liver, the average Cu contents amounted to 24.04 mg kg−1 wet weight, in kidneys to 2.90 mg kg−1 wet weight and in muscles to 0.94 mg kg−1 wet weight. The highest values of copper content in particular tissues and organs were noted in the group of animals with neoplastic changes. In respect to the animal age the highest mean values of the copper content were noted in the oldest animals. They amounted to 30.97 mg kg−1 in the liver, 3.34 mg kg−1 in kidneys and 1.18 mg kg−1 wet weight in muscles. Considering life conditions of the dogs it was observed that the higher mean values in all the investigated organs occurred in dogs coming from the urban areas. 相似文献
77.
Malgorzata Szczepańska Przemyslaw Wirstlein Jana Skrzypczak Pawe? P Jagodziński 《Reproductive biology and endocrinology : RB&E》2012,10(1):1
Background
A decrease in HOXA11 expression in eutopic mid-secretory endometrium has been found in women with endometriosis-associated infertility. 相似文献78.
Anna Mucha-Małecka Bogdan Gliński Marcin Hetnał Magdalena Jarosz Jacek Urbański Beata Frączek-Błachut Paweł Dymek Krzysztof Małecki Agnieszka Chrostowska 《Reports of Practical Oncology and Radiotherapy》2012,17(3):141-145
AimTo report the long-term follow-up of a cohort of adult patients with LGG post-operatively irradiated in one institution, and to identify prognostic factors for progression free survival.BackgroundThere is little consensus about the optimal treatment for low-grade glioma (LGG), and the clinical management of LGG is one of the most controversial areas in neurooncology. Radiation therapy is one option for treatment of patients with LGG, whereas other options include postoperative observation.Materials and methodsBetween 1975 and 2005, 180 patients with LGG (WHO II) received postoperative irradiation after non radical (subtotal or partial) excision. Patients had to be 18 years of age or older, and have histologic proof of supratentorial fibrillary (FA), protoplasmic (PA) or gemistocytic astrocytoma (GA). Radiotherapy was given within 3–10 weeks after surgery. Treatment fields were localized and included the preoperative tumor volume, with a 1–2 cm margin, treated to a total dose of 50–60 Gy in 25–30 fractions over 5–6 weeks.ResultsActuarial ten-year progression free survival (APFS) in the whole group was 19%. The worse prognosis was observed in patients with GA. Ten-year APFS rates for GA, PA and FA were 10%, 18% and 22%, respectively.ConclusionThe findings from our long-term cohort of 180 patients with LGG confirmed by uni- and multivariate analysis demonstrated that only astrocytoma histology significantly determined the prognosis. The best survival was observed in patients with the fibrillary variant, and the worst for the gemistocytic one. 相似文献
79.
Aleksandra Kładna Paweł Berczyński Irena Kruk Teresa Michalska Hassan Y. Aboul‐Enein 《Luminescence》2012,27(6):473-477
The direct effects of the four catecholamines (CATs), adrenaline (A), noradrenaline (NA), dopamine (D) and isoproterenol (I), on free radicals were investigated using the free radical 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH?) and hydroxyl radial (HO?). The CATs examined were found to inhibit the ESR signal intensity of DPPH? in a dose‐dependent manner over the range 0.1–2.5 mmol/L in the following order: NA > A > I > D, with IC50 = 0.30 ± 0.03 for noradrenaline and IC50 = 0.86 ± 0.02 for dopamine. Hydroxyl radicals were produced using a Fenton reaction in the presence of the spin trap 5,5‐dimethyl‐1‐pyrroline N‐oxide (DMPO), and ESR technique was applied to detect the CATs reactivity toward the radicals. The reaction rates constant (kr) of CATs with HO? were found to be in the order of 109 L/mol/s, and the kr value for noradrenaline was the highest (kr = 8.4 × 109 L/mol/s). The CATs examined exhibited also a strong decrease in the light emission (62–73% at 1 mmol/L concentration and 79–89% at 2 mmol/L concentration) from a Fenton‐like reaction. These reactions may be relevant to the biological action of these important polyphenolic compounds. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
80.