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Background and Objective
Emerging evidence indicates that common functional polymorphisms in the estrogen receptor 1 (ESR1) gene may have an impact on an individual’s susceptibility to endometrial cancer, but individually published results are inconclusive. The aim of this meta-analysis is to derive a more precise estimation of the associations between eight polymorphisms in the ESR1 gene and endometrial cancer risk.Methods
A literature search of PubMed, Embase, Web of Science and China Biology Medicine (CBM) databases was conducted on publications published before November 1st, 2012. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Statistical analyses were performed using the STATA 12.0 software.Results
Thirteen case-control studies were included with a total of 7,649 endometrial cancer cases and 16,855 healthy controls. When all the eligible studies were pooled into the meta-analysis, the results indicated that PvuII (C>T) polymorphism was associated with an increased risk of endometrial cancer, especially among Caucasian populations. There were also significant associations between rs3020314 (C>T) polymorphism and an increased risk of endometrial cancer. Furthermore, rs2234670 (S/L) polymorphism may decrease the risk of endometrial cancer. However, no statistically significant associations were found in XbaI (A>G), Codon 325 (C>G), Codon 243 (C>T), VNTR (S/L) and rs2046210 (G>A) polymorphisms.Conclusion
The current meta-analysis suggests that PvuII (C>T) and rs3020314 (C>T) polymorphisms may be risk factors for endometrial cancer, especially among Caucasian populations. 相似文献Background
Aberrant methylation of CpG islands acquired in tumor cells in promoter regions plays an important role in carcinogenesis. Accumulated evidence demonstrates P16INK4a gene promoter hypermethylation is involved in non-small cell lung carcinoma (NSCLC), indicating it may be a potential biomarker for this disease. The aim of this study is to evaluate the frequency of P16INK4a gene promoter methylation between cancer tissue and autologous controls by summarizing published studies.Methods
By searching Medline, EMBSE and CNKI databases, the open published studies about P16INK4a gene promoter methylation and NSCLC were identified using a systematic search strategy. The pooled odds of P16INK4A promoter methylation in lung cancer tissue versus autologous controls were calculated by meta-analysis method.Results
Thirty-four studies, including 2 652 NSCLC patients with 5 175 samples were included in this meta-analysis. Generally, the frequency of P16INK4A promoter methylation ranged from 17% to 80% (median 44%) in the lung cancer tissue and 0 to 80% (median 15%) in the autologous controls, which indicated the methylation frequency in cancer tissue was much higher than that in autologous samples. We also find a strong and significant correlation between tumor tissue and autologous controls of P16INK4A promoter methylation frequency across studies (Correlation coefficient 0.71, 95% CI:0.51–0.83, P<0.0001). And the pooled odds ratio of P16INK4A promoter methylation in cancer tissue was 3.45 (95% CI: 2.63–4.54) compared to controls under random-effect model.Conclusion
Frequency of P16INK4a promoter methylation in cancer tissue was much higher than that in autologous controls, indicating promoter methylation plays an important role in carcinogenesis of the NSCLC. Strong and significant correlation between tumor tissue and autologous samples of P16INK4A promoter methylation demonstrated a promising biomarker for NSCLC. 相似文献Background
A functional -94 insertion/deletion polymorphism (rs28362491) in the promoter of the NFKB1 gene was reported to influence NFKB1 expression and confer susceptibility to different types of cancer. This study aims to determine whether the polymorphism is associated with risk of bladder cancer.Materials and methods
TaqMan assay was used to determine genotype among 609 cases and 640 controls in a Chinese population. Logistic regression was used to assess the association between the polymorphism and bladder cancer risk, and quantitative real-time polymerase chain reaction was used to determine NFKB1 mRNA expression.Results
Compared with the ins/ins/ins/del genotypes, the del/del genotype was associated with a significantly increased risk of bladder cancer [adjusted odd ratio (OR) = 1.92, 95% confidence interval (CI) = 1.42–2.59]. The increased risk was more prominent among subjects over 65 years old (OR = 2.37, 95% CI = 1.52–3.70), male subjects (OR = 1.97, 95% CI = 1.40–2.79) and subjects with self-reported family history of cancer (OR = 3.59, 95% CI = 1.19–10.9). Furthermore, the polymorphism was associated with a higher risk of developing non-muscle invasive bladder cancer (OR = 2.07, 95% CI = 1.51–2.85), grade 1 bladder cancer (OR = 2.40, 95% CI = 1.68–3.43), single tumor bladder cancer (OR = 2.04, 95% CI = 1.48–2.82) and smaller tumor size bladder cancer (OR = 2.10, 95% CI = 1.51–2.92). The expression of NFKB1 mRNA in bladder cancer tissues with homozygous insertion genotype was higher than that with deletion allele.Conclusions
In conclusion, the -94 ins/del ATTG polymorphism in NFKB1 promoter may contribute to the etiology of bladder cancer in the Chinese population. 相似文献Purpose
The purpose of this study was to describe the epidemiology of cervical spine injury in the patients with cervical trauma and analyze its associated risk factors during the special heating season in North China.Methods
This cross-sectional study investigated predictors for cervical spine injury in cervical trauma patients using retrospectively collected data of Hebei Provincial Orthopaedic Hospital from 11/2011 to 02/2012, and 11/2012 to 02/2013. Binary logistic regression analysis was used to determine risk factors for cervical fractures/dislocations or cord injury.Results
A total of 106 patients were admitted into this study. Of all, 34 patients (32.1%) were treated from 11/2011 to 02/2012 and 72 patients (67.9%) from 11/2012 to 02/2013. The mean age was 41.9±13.3 years old; 85 patients (80.2%) were male and 82 (77.4%) from rural areas. Eighty patients (75.5%) were caused by fall including 45 (42.5%) by severe fall (>2 m). Sixty-five patients (61.3%) of all suffered injuries to other body regions and 32 (30.2%) got head injury. Thirty-one patients (29.2%) sustained cervical cord injury with cervical fractures/dislocations. Twenty-six (83.9%) of cervical cord injury patients were from rural areas and 24 (77.4%) of those resulted from fall including 15 (48.4%) from severe fall (>2 m). Logistic regression displayed that age (OR, 1.47; 95% CI, 1.05–2.07), head injury (OR, 5.63; 95% CI, 2.23–14.26), were risk factors for cervical cord injury and snowing (OR, 8.25; 95% CI, 2.26–30.15) was a risk factor for cervical spine injury due to severe fall (>2 m).Conclusions
The elder male patients and patients with head trauma are high-risk population for cervical cord injury. As a seasonal factor, snowing during heating season is of note a risk factor for cervical spine injury resulting from severe fall (>2 m) in the patients with cervical trauma in North China. 相似文献Background
The meiotic program initiation pathway genes (CYP26B1, NANOS1 and STRA8) have been proposed to play key roles in spermatogenesis.Objective
To elucidate the exact role of the genetic variants of the meiosis initiation genes in spermatogenesis, we genotyped the potential functional genetic variants of CYP26B1, NANOS1 and STRA8 genes, and evaluated their effects on spermatogenesis in our study population.Design, Setting, and Participants
In this study, all subjects were volunteers from the affiliated hospitals of Nanjing Medical University between March 2004 and July 2009 (NJMU Infertile Study). Total 719 idiopathic infertile cases were recruited and divided into three groups according to WHO semen parameters: 201 azoospermia patients (no sperm in the ejaculate even after centrifugation), 155 oligozoospermia patients (sperm counts <20×106/ml) and 363 infertility/normozoospermia subjects (sperm counts >20×106/ml). The control group consisted of 383 subjects with normal semen parameters, all of which had fathered at least one child without assisted reproductive technologies.Measurements
Eight single nucleotide polymorphisms (SNPs) in CYP26B1, NANOS1 and STRA8 genes were determined by TaqMan allelic discrimination assay in 719 idiopathic infertile men and 383 healthy controls.Results and Limitations
The genetic variant rs10269148 of STRA8 gene showed higher risk of spermatogenic impairment in the groups of abnormospermia (including azoospermia subgroup and oligozoospermia subgroup) and azoospermia than the controls with odds ratios and 95% confidence intervals of 2.52 (1.29–4.94) and 2.92 (1.41–6.06), respectively (P = 0.006, 0.002 respective). Notably, larger sample size studies and in vivo or in vitro functional studies are needed to substantiate the biological roles of these variants.Conclusions
Our results provided epidemiological evidence supporting the involvement of genetic polymorphisms of the meiotic program initiation genes in modifying the risk of azoospermia and oligozoospermia in a Han-Chinese population. 相似文献The specific and high-level expression of 1Ax1 is determined by different promoter regions. HMW-GS synthesis occurs in aleurone layer cells. Heterologous proteins can be stored in protein bodies.
AbstractHigh-molecular-weight glutenin subunit (HMW-GS) is highly expressed in the endosperm of wheat and relative species, where their expression level and allelic variation affect the bread-making quality and nutrient quality of flour. However, the mechanism regulating HMW-GS expression remains elusive. In this study, we analyzed the distribution of cis-acting elements in the 2659-bp promoter region of the HMW-GS gene 1Ax1, which can be divided into five element-enriched regions. Fragments derived from progressive 5′ deletions were used to drive GUS gene expression in transgenic wheat, which was confirmed in aleurone layer cells, inner starchy endosperm cells, starchy endosperm transfer cells, and aleurone transfer cells by histochemical staining. The promoter region ranging from ??297 to ??1 was responsible for tissue-specific expression, while fragments from ??1724 to ??618 and from ??618 to ??297 were responsible for high-level expression. Under the control of the 1Ax1 promoter, heterologous protein could be stored in the form of protein bodies in inner starchy endosperm cells, even without a special location signal. Our findings not only deepen our understanding of glutenin expression regulation, trafficking, and accumulation but also provide a strategy for the utilization of wheat endosperm as a bioreactor for the production of nutrients and metabolic products.
相似文献Since the 1970s, extensive croplands were converted to forest and pasture lands to control severe soil erosion on the Loess Plateau of China. We quantify the direct and indirect effects of vegetation restoration on runoff and sediment yield on hillslopes in the field to improve environmental governance.
MethodsAn artificial rainfall experiment at a rainfall intensity of 120 mm h−1 and a slope gradient of 22° were used to distinguish the effects of vegetation restoration on runoff and sediment yield.
ResultsCompared to the farmland slopes, vegetation restoration directly prolonged the time-to-runoff by 140%, reduced the runoff rate by 20%, and increased the soil infiltration capacity by 15%. Vegetation restoration indirectly delayed the time-to-runoff by 120%, reduced the runoff rate and sediment yield rate by 50% and 94%, respectively, and increased the soil infiltration capacity by 58% on the hillslopes with vegetation restoration.
ConclusionsThe direct effects of vegetation restoration on runoff and sediment yield were lower than its indirect impacts. Vegetation cover, decreases in soil bulk density, and increases in belowground root biomasses and > 0.25 mm aggregate stability were the primary causes of runoff and sediment yield reduction on the slopes with vegetation restoration.
相似文献