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排序方式: 共有491条查询结果,搜索用时 390 毫秒
91.
Ozt��rk Ozdemir Ilhan Sezgin Hande Kucuk Kurtulgan Ferhan Candan Binnur Koksal Haldun Sumer Dilara Icagasioglu Atilla Uslu Fazilet Yildiz Sulhattin Arslan Selma Cetinkaya Senol Citli Zekeriya Oztemur Mansur Kayatas 《Molecular biology reports》2011,38(5):3195-3200
The Familial Mediterranean Fever (FMF) shows an autosomal recessive pattern of inheritance and affects certain ethnic groups. Disease is caused by mutations in MEFV gene and more than 180 mutations have been defined in affected individuals. Current study aimed to determine the frequency-type of the mutations for MEFV gene in Sivas??middle Anatolian city. The cohort was composed of 3340 patients. MEFV gene mutations were studied by multiplex PCR based reverse hybridization stripAssay method. Patients?? clinical features were; family history: 68%, erysipelas-like erythema: 17.6%, fever: 89.9%, abdominal pain: 84.2%, peritonitis: 90.2%, arthritis: 33%, pleuritis: 14.2%, parental consanguinity: 21.2%. Current results revealed that M694V is the most frequent mutation (43.12%), followed by E148Q (20.18), M680I(G/C) (15.00%) and V726A (11.32%). The study population has a high rate of carriers and the E148Q mutation frequency was found to be highest when compared to the other regions of Turkey and other Mediterranean groups. 相似文献
92.
Venous thrombosis is a significant cause of morbidity and mortality in patients with malignancies. We aimed to investigate
the association between prothrombotic gene polymorphisms detected in lung cancer cases and deep venous thrombosis (DVT). Totally
66 patients with an established diagnosis of lung cancer, of which 33 developed DVT, were enrolled. Multiplex PCR technique
and reverse hybridization strip assay were performed on DNA extracted from peripheral blood, in order to analyze prothrombin
G20210A, factor V G1691A, methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, angiotensin converting enzyme (ACE),
plasminogen activator inhibitor-1 (PAI-1), and glycoprotein IIIa (Gp IIIa) gene mutations. Among prothrombotic gene polymorphisms
investigated in this study, the commonest ones were PAI-1 4G/5G (56% heterozygous, 39% homozygous) and ACE gene mutations
(58% heterozygous, 17% homozygous). The presence of homozygous MTHFR A1298C mutation was significantly associated with DVT
(P = 0.020). Comparing the lung cancer patients with and without DVT, only MTHFR A1298C gene polymorphism differed significantly
(P = 0.040). We determined a higher rate of prothrombotic gene mutations in lung cancer patients who developed DVT. However,
statistical significance was achieved only for MTHFR A1298C gene mutation. Therefore, nongenetic factors for disturbance of
hemostatic metabolism should also be considered in lung cancer patients. 相似文献
93.
Tumor necrosis factor-alpha (TNF-α) and interleukin 1 beta (IL-1β) genetic variants which resulting in TNF-α and IL-1 overproduction
may increase susceptibility to autoimmune diseases such as atherosclerosis. We have studied the association of TNF-α G308A
and IL-1β (+3953) C/T polymorphism with myocardial infarction in Turkish population. 143 patients with myocardial infarction
and 213 age-matched healthy controls were included in the study. In univariant analysis, the frequencies of IL-1β, TNF-α genotype
or allele, and haplotype of C:A and T:A were significantly elevated in patients when compared with those of controls. GA genotype
of TNF-α, T allele of IL-1β and A of TNF-α allele seem to be risk factors for myocardial infarction. In contrast, CC genotype
of IL-1β and GG genotype of TNF-α have protective effect against myocardial infarction. In multivariate logistic regression
analysis, TNF-α A allele, gender and smoking were associated with myocardial infarction. In conclusion, we can state that
TNF-α A allele might be associated with myocardial infarction. 相似文献
94.
Aydin S Dag E Ozkan Y Arslan O Koc G Bek S Kirbas S Kasikci T Abasli D Gokcil Z Odabasi Z Catak Z 《Peptides》2011,32(6):1276-1280
A relationship between hormones and seizures has been reported in animals and humans. Therefore, the purpose of this study was to investigate the association between serum levels of prolactin, nesfatin-1 and ghrelin measured different times after a seizure or non-epileptic event and compared with controls. The study included a total of 70 subjects, and of whom 18 patients had secondary generalized epilepsy (SGE), 16 patients had primary generalized epilepsy (PGE), 16 patients exhibited paroxysmal event (psychogenic) and 20 healthy males were control subjects. The first sample was taken within 5 min of a seizure, with further samples taken after 1, 24, and 48 h so long as the patient did not exhibit further clinically observable seizures; blood samples were taken once from control subjects. Prolactin was measured immediately using TOSOH Bioscience hormone assays. Nesfatin-1 and ghrelin peptides were measured using a commercial immunoassay kit. Patients suffering from focal epilepsy with secondary generalization and primary generalized epilepsy presented with significantly higher levels of serum prolactin and nesfatin-1 and lower ghrelin levels 5 min, 1 and 24 h after a seizure than patients presenting with paroxysmal events (psychogenic) and control subjects; the data were similar but not statistically significant after 48 h. The present study suggests that increased serum prolactin and nesfatin-1 concentrations, decreased ghrelin concentrations could be used as markers to identify patients that have suffered a recent epileptic seizure or other paroxysmal event (psychogenic). 相似文献
95.
Iron overload is a major health problem for patients who have to have continuous blood transfusions. It brings some metabolic problems together. Various iron chelating agents are being used for treatment of hemochromatosis which arises from excess iron accumulation. This study was conducted with the aim of determining whether deferasirox used as an iron chelator in patients with hemochromatosis has genotoxic effects. Commercial form of deferasirox, Exjade was used as test material. Test material showed a general mutagen character in mutant strains of Salmonella typhimurium. Deferasirox has also led to an increase in mutagenity-related polymorphic band count in random amplification of polymorphic DNA test done with bone marrow cells of rats. Similarly, test material has increased micronucleus formation in cultured in vitro human peripheral lymphocytes particularly in 48 h period. Consistently with the abovementioned findings, deferasirox reduced nuclear division index (NDI) compared to controls and some part of these reductions are statistically significant. NDI reductions were found at positive control levels at high concentrations. 相似文献
96.
β‐Hydroxyamide‐Based Ligands and Their Use in the Enantioselective Borane Reduction of Prochiral Ketones
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Hydroxyamide‐based ligands have occupied a considerable place in asymmetric synthesis. Here we report the synthesis of seven β‐hydroxyamide‐based ligands from the reaction of 2‐hydroxynicotinic acid with chiral amino alcohols and test their effect on the enantioselective reduction of aromatic prochiral ketones with borane in tetrahydofuran (THF). They produce the corresponding secondary alcohols with up to 76% enantiomeric excess (ee) and good to excellent yields (86‐99%). Chirality 26:21–26, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
97.
Pierre‐Alexandre Rastorgueff Pierre Chevaldonné Defne Arslan Caroline Verna Christophe Lejeusne 《Molecular ecology》2014,23(11):2825-2843
The marine cave‐dwelling mysid Hemimysis margalefi is distributed over the whole Mediterranean Sea, which contrasts with the poor dispersal capabilities of this brooding species. In addition, underwater marine caves are a highly fragmented habitat which further promotes strong genetic structuring, therefore providing highly informative data on the levels of marine population connectivity across biogeographical regions. This study investigates how habitat and geography have shaped the connectivity network of this poor disperser over the entire Mediterranean Sea through the use of several mitochondrial and nuclear markers. Five deeply divergent lineages were observed among H. margalefi populations resulting from deep phylogeographical breaks, some dating back to the Oligo‐Miocene. Whether looking at the intralineage or interlineage levels, H. margalefi populations present a high genetic diversity and population structuring. This study suggests that the five distinct lineages observed in H. margalefi actually correspond to as many separate cryptic taxa. The nominal species, H. margalefi sensu stricto, corresponds to the westernmost lineage here surveyed from the Alboran Sea to southeastern Italy. Typical genetic breaks such as the Almeria‐Oran Front or the Siculo‐Tunisian Strait do not appear to be influential on the studied loci in H. margalefi sensu stricto. Instead, population structuring appears more complex and subtle than usually found for model species with a pelagic dispersal phase. The remaining four cryptic taxa are all found in the eastern basin, but incomplete lineage sorting is suspected and speciation might still be in process. Present‐day population structure of the different H. margalefi cryptic species appears to result from past vicariance events started in the Oligo‐Miocene and maintained by present‐day coastal topography, water circulation and habitat fragmentation. 相似文献
98.
99.
Stable coronary artery disease (CAD) can cause repetitive reversible myocardial ischaemia, and it seems to be possible that reversibly injured myocardium releases small amounts of soluble cytoplasmic proteins. Hence, the aim was to evaluate the effect of stable CAD on baseline serum levels of cardiac biomarkers. We studied 68 consecutive outpatients referred for gated myocardial perfusion imaging. Before a treadmill exercise test, blood samples for measurement of creatine kinase (CK), CK-myocardial band (CK-MB) mass, myoglobin, aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were collected. Normal perfusion patterns were detected in 29 (43%) patients (group 1) and perfusion defects were detected in 39 (57%) patients (group 2). Baseline serum levels of biomarkers except CK were significantly higher in group 2 (p=0.001). Stable CAD increases baseline levels of CK-MB mass, myoglobin, AST and LDH in the serum and this increase is related to the extent and severity of the perfusion defect and to some extent the ejection fraction of the left ventricle. 相似文献
100.
Protease deficient recA431 mutants of Escherichia coli are defective in their capacity for induction of SOS responses and were intermediate in their sensitivities to ultraviolet light (UV) and cis-platinum(II)diamminodichloride (cis-PDD). Survival after treatment determined as colony forming ability was greater in rec+ strains and decreased in recA13 mutants which are defective in both recA proteolytic and recombination capabilites. In contrast, recA431 mutants were as sensitive to N-methyl-N′-nitro-N-nitrosoguanidine (NTG) as the recA13 cells. When cells carried either the pKM101 or N3 plasmid, survival after treatment with the three mutagens was increased. Presence of these plasmids in cells also resulted in hypermutagenicity as indicated by reversion of the argE3 mutation using a modified Ames test. Mutagenesis by NTG and cis-PDD was increased, as was survival of cells treated with UV light, cis-PDD and NTG in both recA+ and recA431 (protease deficient) strains. No plasmid mediated enhancement of mutagenesis or cell survival was observed in recA13 mutants. Thus, the ability of the plasmids to enhance cell survival and mutagenesis was dependent on recombination proficiency of the recA gene product and not its regulatory proteolytic activity. Unlike UV or NTG, presence of one of these plasmids was needed to detect reversion of the argE3 mutation by cis-PDD. 相似文献