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71.
72.
Ghabaee M Bayati A Amri Saroukolaei S Sahraian MA Sanaati MH Karimi P Houshmand M Sadeghian H Hashemi Chelavi L 《Cellular and molecular neurobiology》2009,29(1):109-114
Multiple sclerosis (MS) is prototype of inflammatory demyelinating disease of the central nervous system .The etiology of
MS remains unclear, but according to current data the disease develops in genetically susceptible individuals and may require
additional environmental triggers. The human leukocyte antigen (HLA) class II alleles (DRB1*1501, DQA1*0102, DQB1*0602) may
have the strongest genetic effect in MS. In this study, the role of these alleles were investigated in 183 Iranian patients
with multiple sclerosis and compared with 100 healthy individuals. HLA typing for DRB1*1501, DQA1*0102, DQB1*0602 was performed
by polymerase chain reaction (PCR) amplification with sequence-specific primers (PCR-SSP) method. The results show that, HLA
DR B1*1501 was significantly more frequent among MS patients (46% vs. 20%, PV = 0.0006) but DQA1*0102 haplotype was negatively
associated with MS (30% vs. 50%, PV = 0.0049) and no significant association was found with DQB1*0602 and MS patients in comparison
with control group (24% and 30%, PV = 0.43). No significant correlation was observed among these alleles with sex, type of
disease; initial symptoms, expanded disability status scale (EDSS), as well as age at onset and familial MS. This study therefore
indicates that there is no association of above HLA haplotypes with clinical presentation, disease duration, and disability
in Iranian patients with MS which is in line with other previous studies in different ethnic groups. 相似文献
73.
Christine Kubiak Fernando de Andres-Trelles Wolfgang Kuchinke Karl-Heinz Huemer Steffen Thirstrup Kate Whitfield Christian Libersa Béatrice Barraud Xina Grählert Gabriele Dreier Ruth Grychtol Zsuzsa Temesvari Gyorgy Blasko Gabriella Kardos Timothy O'Brien Margaret Cooney Siobhan Gaynor Arrigo Schieppati Nuria Sanz Raquel Hernandez Charlotte Asker-Hagelberg Hanna Johansson Sue Bourne Jane Byrne Adeeba Asghar Jean-Marc Husson Christian Gluud Jacques Demotes-Mainard 《Trials》2009,10(1):1-7
Background
Idiopathic recurrent miscarriage is defined as 3 consecutive pregnancy losses with no contributing features found on investigations. At present there are no treatments of proven efficacy for idiopathic recurrent miscarriage. Uterine natural killer (uNK) cells, the most predominant leucocyte in the endometrium are adjacent to foetal trophoblast cells and thought to be involved in implantation. The exact mechanisms of how uNK cells affect implantation are not clear but are probably through the regulation of angiogenesis. Multiple studies have shown an association between high density of uterine natural killer cells and recurrent miscarriage. We have shown that prednisolone reduces the number of uNK cells in the endometrium. The question remains as to whether reducing the number of uNK cells improves pregnancy outcome.Methods
We propose a randomised, double-blind, placebo controlled trial of prednisolone with a pilot phase to assess feasibility of recruitment, integrity of trial procedures, and to generate data to base future power calculations. The primary aim is to investigate whether prednisolone therapy during the first trimester of pregnancy is able to improve live birth rates in patients with idiopathic recurrent miscarriage and raised uNK cells in the endometrium. Secondary outcomes include conception rate, karyotype of miscarriage, miscarriages (first and second trimester), stillbirths, pregnancy complications, gestational age at delivery, congenital abnormality and side effects of steroids. The trial has 2 stages: i) screening of non-pregnant women and ii) randomisation of the pregnant cohort. All patients who fit the inclusion criteria (<40 years old, ≥3 consecutive miscarriages with no cause found and no contraindications to prednisolone therapy) will be asked to consent to an endometrial biopsy in the mid-luteal phase to assess their levels of uNK cells. Women with high levels of uNK cells (≥5%), will be randomised to either prednisolone or placebo when a pregnancy is confirmed. Follow-up includes 2 weekly ultrasound scans in the first trimester, an anomaly scan at 20 weeks gestation, growth scans at 28 and 34 weeks gestation and a postnatal follow-up at 6 weeks.Trial Registration
Current Controlled Trials ISRCTN28090716 相似文献74.
Shaheen Asghar Andres Magnusson Azad Khan Keramat Ali Akhtar Hussain 《Obesity (Silver Spring, Md.)》2010,18(6):1143-1145
The aim of this study was to examine whether the association between overweight and depression usually found in western societies would also be found in locations where overweight is not stigmatized. A total of 1,271 individuals from rural Bangladesh were randomly selected; the response rate was 76%. Depressive symptoms were measured with the Montgomery‐Åsberg Depression Rating Scale (MADRS). The sum MADRS scores were 13.4 (s.d. = 5.8) and 18.5 (8.1) for overweight vs. nonoverweight (t = 6.6; P < 0.000) men, respectively, and 19.7 (7.8) and 23.2 (7.9) for overweight vs. nonoverweight women, respectively (t = 4.2; P < 0.000). Thus the MADRS score was lower in overweight individuals. After adjusting for sex and age, BMI significantly predicted the MADRS score (β = ?0.3; t = 10.2; P < 0.000). These findings suggest that overweight may be related to fewer depressive symptoms in non western cultures. 相似文献
75.
Aamir J Khan Hailemichael Gebreselassie Edwin J Asturias Mubina Agboatwalla Redda Teklehaimanot Stephen P Luby Berhane Beyene Berhane Bayene Claudia Chezzi Humayun Asghar Tariq Moatter Olga R Torres Olen Kew Jerry Winkelstein Neal A Halsey 《Biologicals》2006,34(2):113-116
Persons who have developed acute flaccid paralysis following infection with wild-type polioviruses or vaccine-associated paralytic poliomyelitis usually excrete polioviruses for only a few weeks. However, some patients with paralytic poliomyelitis have had prolonged excretion of polioviruses for periods of up to 10 years after onset of disease. Most prolonged excretors have been identified in industrialized countries. We studied 348 patients 2-28 years old in Ethiopia, Pakistan and Guatemala with residual paralytic poliomyelitis to determine if they had IgA or IgG deficiency or persistent poliomyelitis excretion at least 1 year after onset of disease. None of the 348 affected individuals had IgG deficiency or persistent poliovirus excretion. One child had borderline low serum IgA concentration. Since we did not study children under 2 years of age, persons born with IgG deficiency disorders may have died in developing countries where replacement immunoglobulin therapy is not readily available. Nevertheless, persistent poliovirus excretion among persons 2 years of age and older with residual paralytic poliomyelitis is uncommon in developing countries. 相似文献
76.
Khair Un Nisa Attiq Ur Rehman Kakar Muhammad Asghar Samiullah Naqeebullah Niamatullah Arif Shah 《Luminescence》2023,38(5):647-661
A flow injection (FI) methodology using the acidic potassium permanganate (KMnO4)–rhodamine-B (Rh-B) reaction with chemiluminescence (CL) detection was established to determine acetochlor and cartap-HCl pesticides in freshwater samples. Experimental parameters were optimized, and Chelex-100 cationic exchanger mini column and solid-phase extraction (SPE) were used as phase separation techniques. Linear calibration curves were observed for the standard solutions of acetochlor and cartap-HCl over the ranges 0.005–2.0 mg L−1 [y = 1155.8x + 57.551, R2 = 0.9999 (n = 8)] and 0.005–1.0 mg L−1 [y = 979.76x + 14.491, R2 = 0.9998 (n = 8)] with LODs and LOQs of 7.5 × 10−4 and 8.0 × 10−4 mg L−1 (3σ blank) and 2.5 × 10−3 and 2.7 × 10−3 mg L−1 (10σ blank), respectively, with an injection throughput of 140 h−1. These methods were used to estimate acetochlor and cartap-HCl with or without the SPE procedure, respectively, in spiked freshwater samples. Results obtained were not significantly different at a 95% confidence level to those of other reported methods. Recoveries for acetochlor and cartap-HCl were obtained over the ranges 93–112% (RSD = 1.9–3.6%) and 98–109% (RSD = 1.7–3.8%), respectively. The most probable CL reaction mechanism was explored. 相似文献
77.
Naveed Asghar Pontus Lindblom Wessam Melik Richard Lindqvist Mats Haglund Pia Forsberg Anna K. ?verby ?shild Andreassen Per-Eric Lindgren Magnus Johansson 《PloS one》2014,9(7)
The increased distribution of the tick-borne encephalitis virus (TBEV) in Scandinavia highlights the importance of characterizing novel sequences within the natural foci. In this study, two TBEV strains: the Norwegian Mandal 2009 (questing nymphs pool) and the Swedish Saringe 2009 (blood-fed nymph) were sequenced and phylogenetically characterized. Interestingly, the sequence of Mandal 2009 revealed the shorter form of the TBEV genome, similar to the highly virulent Hypr strain, within the 3′ non-coding region (3′NCR). A different genomic structure was found in the 3′NCR of Saringe 2009, as in-depth analysis demonstrated TBEV variants with different lengths within the poly(A) tract. This shows that TBEV quasispecies exists in nature and indicates a putative shift in the quasispecies pool when the virus switches between invertebrate and vertebrate environments. This prompted us to further sequence and analyze the 3′NCRs of additional Scandinavian TBEV strains and control strains, Hypr and Neudoerfl. Toro 2003 and Habo 2011 contained mainly a short (A)3C(A)6 poly(A) tract. A similar pattern was observed for the human TBEV isolates 1993/783 and 1991/4944; however, one clone of 1991/4944 contained an (A)3C(A)11 poly(A) sequence, demonstrating that quasispecies with longer poly(A) could be present in human isolates. Neudoerfl has previously been reported to contain a poly(A) region, but to our surprise the re-sequenced genome contained two major quasispecies variants, both lacking the poly(A) tract. We speculate that the observed differences are important factors for the understanding of virulence, spread, and control of the TBEV. 相似文献
78.
The insulin receptor (IR) and its signaling appear to be essential for insulin secretion from pancreatic beta-cells. However, much less is known about the role of the IR in alpha-cells. To assess the role of the IR in glucagon and insulin secretion, we engineered adeno-viruses for high efficiency small interference RNA (siRNA)-IR expression in isolated mouse pancreatic islets and lentiviruses for siRNA-IR expression in pancreatic alpha- and beta-cell lines (alpha-TC6 and MIN6) with specific, long term stable IR knockdown. Western blot analysis showed that these strategies resulted in 60-80% reduction of IR protein in islets and alpha- and beta-cell lines. Cell growth was reduced by 35-50% in alpha-TC and MIN6 cells stably expressing siRNA-IR, respectively. Importantly, glucagon secretion, in response to glucose (25 to 2.8 mm), was completely abolished in islets expressing siRNA-IR, whereas secretion increased 1.7-fold in islets expressing control siRNA. In contrast, there was no difference in glucose-stimulated insulin secretion when comparing siRNA-IR and siRNA control, with both groups showing a 1.7-fold increase. Islet glucagon and insulin content were also unaffected by IR knockdown. To further explore the role of the IR, siRNA-IR was stably expressed in pancreatic cell lines, which dramatically suppressed glucose-regulated glucagon secretion in alpha-TC6 cells (3.4-fold) but did not affect GSIS in MIN6 cells. Defects in siRNA-IR-expressing alpha-cells were associated with an alteration in the activity of Akt and p70S6K where insulin-induced phosphorylation of protein kinase B/AKt was greatly reduced while p70S6K activation was enhanced, suggesting that the related pathways play important roles in alpha cell function. This study provides direct evidence that appropriate expression of the IR in alpha-cells is required for glucose-dependent glucagon secretion. 相似文献
79.
Bijan Ansari-Moghaddam Ali Asghar Kiani Ali Sheikhian Mehdi Birjandi Seyyed Amir Yasin Ahmadi Nazanin Mousavi Hamzeh Ali Torang Farhad Shahsavar 《Reports of Biochemistry & Molecular Biology》2021,10(1):84
Background:The pathophysiology underlying the progression and development of autoimmune conditions, such as Rheumatoid Arthritis (RA), is a result of dysregulations of the immune system. Research has explored the genetic alterations present in RA; however, limited studies have examined the role of Killer cell Immunoglobulin-like Receptors (KIR) and Human Leukocyte Antigen (HLA) molecules in RA. Therefore, the aim of this study was to examine KIR genes, their HLA ligands, and KIR-HLA compounds in patients with RA.Methods:In this case-control study, a total of 50 patients with RA and 100 healthy individuals were enrolled. DNA samples were evaluated using PCR with sequence specific Primers (PCR-SSP). Odds ratio (OR) with a 95% confidence interval (CI) were reported.Results:Among the KIR genes examined, KIR2DLA (p= 0.0255, OR= 0.389, 95% CI= 0.210-0.722) and KIR2DS4-full (p< 0.0001, OR= 6.163, 95% CI= 3.174-11.968) were observed to have a statistically significant correlation with disease susceptibility to RA. As an inhibitory gene, KIR2DLA was observed to have a protective effect against RA while KIR2DS4-full as an activating gene, was found to increase risk for RA. No significant associations were found between any of the other KIR genotypes, HLA ligands, or KIR-HLA compounds examined in this study to RA susceptibility. Conclusion:In this study of RA in the Lur population of Iran, KIR2DS4-full was observed to increase susceptibility to RA, while KIR2DL5A was found to act as a protecting factor based on both the cross Table and regression analyses. Further research should focus on repeating this study in additional populations.Key Words: HLA, KIR, NK cells, Rheumatoid Arthritis 相似文献
80.
Asghar Ghasemi Fatemeh Mehrazin Saleh Zahediasl 《Journal of physiology and biochemistry》2013,69(4):751-759
Reduced nitric oxide availability and a heterogeneous pattern of nitric oxide synthase activity in some tissues have been reported in hypothyroidism. This study aimed at determining the effects of oral nitrate and l-arginine administration on serum, heart, and aorta nitric oxide metabolite concentrations in fetal hypothyroid rats. In an experimental study, pregnant Wistar rats were administrated tap water or 0.02 % of 6-propyl-2-thiouracil in drinking water during pregnancy and their male pups were followed (n?=?8/group). In adult progeny, serum, heart, and aorta nitric oxide metabolite concentrations were measured by the Griess method after 1-week administration of sodium nitrate (500 mg/L) or l-arginine (2 %) in drinking water. Serum thyroid hormone and thyroid-stimulating hormone levels were also measured. Compared to controls, fetal hypothyroid progeny had significantly lower nitric oxide metabolite concentrations in heart (0.32?±?0.07 vs. 0.90?±?0.14 nmol/mg protein, p?=?0.004) and aorta (2.98±0.56 vs. 6.15±0.74 nmol/mg protein, p?=?0.011) tissues. Nitrate therapy restored heart nitric oxide metabolite levels decreased by fetal hypothyroidism, while l-arginine administration further decreased aorta nitric oxide metabolite levels. Sodium nitrate increased and l-arginine decreased serum nitric oxide metabolite levels in both control and fetal hypothyroid animals. In conclusion, nitrate therapy restores decreased heart nitric oxide metabolite levels, whereas l-arginine decreases aorta nitric oxide metabolite levels even further in fetal hypothyroid rats, findings relevant to the cardiovascular consequences of congenital hypothyroidism in adulthood. 相似文献