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991.
Z K Shikary S S Betrabet Z M Patel S Patel J V Joshi V S Toddywala S P Toddywala D M Patel K Jhaveri B N Saxena 《Contraception》1987,35(5):477-486
The transfer of levonorgestrel (LNG) from the maternal plasma via breast milk to the infant was studied in 38 fully lactating and breast-feeding women at 4-6 weeks postpartum, for a duration of 28 days. These volunteers were provided with LNG contraceptive treatment delivered through three, different routes of drug delivery system: (i) intrauterine devices impregnated with LNG (LNG-IUD); (ii) subdermal implant (Norplant (R)-2); and (iii) minipills (LNG 30 micrograms daily). On the first day after either the LNG-IUD (n = 14 women) or Norplant (R)-2 (n = 14 women) insertion, the maternal blood and breast milk samples were collected at 2, 4 and 8 hourly intervals. This was followed by daily collection of these samples as well as infant's blood from days 2 to 4 and thereafter on days 7, 14 and 28. For infant's blood samples from LNG minipill users (n = 10 women), only a single 4-hour sample was collected on the first day and no samples were collected on days 3 and 4. The rest of the schedule for collection of maternal blood and breast milk as well as infant's blood samples were the same in minipill users as for the other two treatment groups. The study revealed a lower LNG percentage transfer from maternal sera to breast milk--11.8 +/- 2, 7 +/- 2 and 8 +/- 1 and relatively higher percentage LNG transfer from breast milk to infant's sera--75 +/- 17, 68 +/- 20 and 32 +/- 3, in LNG-IUD, Norplant (R)-2 and minipill users, respectively. Therefore, LNG contraceptive steroid is transferred into the infant's circulation, the biological significance of which remains to be established. 相似文献
992.
Mai Fujiwara Radhika Raheja Lucien P. Garo Amrendra K. Ajay Ryoko Kadowaki-Saga Sukrut H. Karandikar Galina Gabriely Rajesh Krishnan Vanessa Beynon Anu Paul Amee Patel Shrishti Saxena Dan Hu Brian C. Healy Tanuja Chitnis Roopali Gandhi Howard L. Weiner Gopal Murugaiyan 《The Journal of clinical investigation》2022,132(10)
993.
Taniya Sharma Nikita Kundu Sarvpreet Kaur Amlan Chakraborty Aman Kumar Mahto Rikeshwer Prasad Dewangan Jadala Shankaraswamy Sarika Saxena 《RSC advances》2022,12(34):21760
Research in recent decades has revealed that the guanine (G)-quadruplex secondary structure in DNA modulates a variety of cellular events that are mostly related to serious diseases. Systems capable of regulating DNA G-quadruplex structures would therefore be useful for the modulation of various cellular events to produce biological effects. A high specificity for recognition of telomeric G-quadruplex has been observed for BLM helicase. We identified peptides from the HRDC domain of BLM using a molecular docking approach with various available solutions and crystal structures of human telomeres and recently created a peptide library. Herein, we tested one peptide (BLM HRDC peptide) from the library and examined its interaction with human telomeric variant-1 (HTPu-var-1) to understand the basis of G4-protein interactions. Our circular dichroism (CD) data showed that HTPu-var-1 folded into an anti-parallel G-quadruplex, and the CD intensity significantly decreased upon increasing the peptide concentration. There was a significant decrease in hypochromicity due to the formation of G-quadruplex-peptide complex at 295 nm, which indicated the unfolding of structure due to the decrease in stacking interactions. The fluorescence data showed quenching upon titrating the peptide with HTPu-var-1-G4. Electrophoretic mobility shift assay confirmed the unfolding of the G4 structure. Cell viability was significantly reduced in the presence of the BLM peptide, with IC50 values of 10.71 μM and 11.83 μM after 72 and 96 hours, respectively. These results confirmed that the selected peptide has the ability to bind to human telomeric G-quadruplex and unfold it. This is the first report in which a peptide was identified from the HRDC domain of the BLM G4-binding protein for the exploration of the G4-binding motif, which suggests a novel strategy to target G4 using natural key peptide segments.Schematic representation of (HTPu–var-1-G4) located at the 3′ end, formation of G-quadruplex, model of the G-quadruplex structure, base stacking between G-quadruplex planes, G-quadruplex structure-peptide complex and twisting of G-quadruplex planes upon peptide binding. 相似文献
994.
Junxi Liu Rebecca C. Richmond Jack Bowden Ciarrah Barry Hassan S. Dashti Iyas Daghlas Jacqueline M. Lane Samuel E. Jones Andrew R. Wood Timothy M. Frayling Alison K. Wright Matthew J. Carr Simon G. Anderson Richard A. Emsley David W. Ray Michael N. Weedon Richa Saxena Deborah A. Lawlor Martin K. Rutter 《Diabetes care》2022,45(4):772
OBJECTIVETo examine the effects of sleep traits on glycated hemoglobin (HbA1c).RESEARCH DESIGN AND METHODSThis study triangulated evidence across multivariable regression (MVR) and one- (1SMR) and two-sample Mendelian randomization (2SMR) including sensitivity analyses on the effects of five self-reported sleep traits (i.e., insomnia symptoms [difficulty initiating or maintaining sleep], sleep duration, daytime sleepiness, napping, and chronotype) on HbA1c (in SD units) in adults of European ancestry from the UK Biobank (for MVR and 1SMR analyses) (n = 336,999; mean [SD] age 57 [8] years; 54% female) and in the genome-wide association studies from the Meta-Analyses of Glucose and Insulin-Related Traits Consortium (MAGIC) (for 2SMR analysis) (n = 46,368; 53 [11] years; 52% female).RESULTSAcross MVR, 1SMR, 2SMR, and their sensitivity analyses, we found a higher frequency of insomnia symptoms (usually vs. sometimes or rarely/never) was associated with higher HbA1c (MVR 0.05 SD units [95% CI 0.04–0.06]; 1SMR 0.52 [0.42–0.63]; 2SMR 0.24 [0.11–0.36]). Associations remained, but point estimates were somewhat attenuated after excluding participants with diabetes. For other sleep traits, there was less consistency across methods, with some but not all providing evidence of an effect.CONCLUSIONSOur results suggest that frequent insomnia symptoms cause higher HbA1c levels and, by implication, that insomnia has a causal role in type 2 diabetes. These findings could have important implications for developing and evaluating strategies that improve sleep habits to reduce hyperglycemia and prevent diabetes. 相似文献
995.
Working Group on Pediatric Acute Rheumatic Fever Cardiology Chapter of Indian Academy of Pediatrics Saxena A Kumar RK Gera RP Radhakrishnan S Mishra S Ahmed Z 《Indian pediatrics》2008,45(7):565-573
JUSTIFICATION: Acute rheumatic fever and rheumatic chronic valvular heart disease is an important preventable cause of morbidity and mortality in suburban and rural India. Its diagnosis is based on clinical criteria. These criteria need verification and revision in the Indian context. Furthermore, there are glaring differences in management protocols available in literature. These facts prompted Indian Academy of Pediatrics to review the management of rheumatic fever. PROCESS: Management of Rheumatic fever was reviewed and recommendation was formulated at national consultative meeting on 20th May 2007 at New Delhi. OBJECTIVES: To formulate uniform guidelines on management of acute rheumatic fever and rheumatic heart disease in the Indian context. Guidelines were formulated for the management of streptococcal pharyngitis, acute rheumatic fever and its cardiac complication as well as secondary prophylaxis for recurrent episodes. RECOMMENDATIONS: (1) Streptococcal eradication with appropriate antibiotics (Benzathine penicillin single dose or penicillin V oral or azithromycin). (2) Diagnosis of rheumatic fever based on Jones criteria. (3) Control inflammatory process with aspirin with or without steroids (total duration of treatment of 12 weeks). (4) Treatment of chorea according to severity (therapy to continue for 2-3 weeks after clinical improvement). (5) Protocol for managing cardiac complication like valvular heart disease, congestive heart failure and atrial fibrillation. (6) Secondary prophylaxis with benzathine penicillin and management of anaphylaxis. 相似文献
996.
Joan SK Ng FRCS William Wong FRCP Ricky WK Law FRCS Joannie Hui MRCP Esther N Wong MRCP Dennis SC Lam FRCOphth 《Clinical & experimental ophthalmology》2001,29(4):239-243
Purpose : To investigate ocular complications arising from nephrotic syndrome and/or its treatments in children. Methods : A cross‐sectional study was conducted in a teaching hospital. A total of 31 paediatric patients with nephrotic syndrome were studied. Comprehensive ophthalmic assessments on best‐corrected visual acuity, intraocular pressure, slit‐lamp and fundus examination were taken. Information regarding histological diagnosis of nephrotic syndrome and its treatment regimen in each patient was reviewed and analysed. Results : Bilateral posterior subcapsular cataracts were detected in three of 29 patients (10.3%) who received steroid therapy. Two had normal vision while one had visual acuity reduced to 6/15 in both eyes. The age of onset of the nephrotic syndrome in these three patients was 2 years, which was significantly younger than those without cataract (5.4 ± 3.2 years, P < 0.001). Three patients (9.7%) had isolated asymptomatic fundal findings of tortuous and dilated retinal vessels. Hypertensive retinopathy was found in one patient (3.2%). No steroid‐induced glaucoma, uveitis, ocular infection, or other eye complications related to the use of steroids or other immunosuppressive agents were noted. Conclusions : Children who have nephrotic syndrome often require prolonged, intermittent high dose of systemic corticosteroid therapy. Paediatricians should be aware of the potential risk of developing steroid‐related complications, especially posterior subcapsular cataract. It appears to have a higher risk when steroid therapy is used in very young patients. Early detection would help to prevent amblyopia development, particularly in the group of immature eyes. 相似文献
997.
998.
Jing Ma Adrien Guillot Zhihong Yang Bryan Mackowiak Seonghwan Hwang Ogyi Park Brandon J. Peiffer Ali Reza Ahmadi Luma Melo Praveen Kusumanchi Nazmul Huda Romil Saxena Yong He Yukun Guan Dechun Feng Pau Sancho-Bru Mengwei Zang Andrew MacGregor Cameron Ramon Bataller Frank Tacke Zhaoli Sun Suthat Liangpunsakul Bin Gao 《The Journal of clinical investigation》2022,132(14)
Intrahepatic neutrophil infiltration has been implicated in severe alcoholic hepatitis (SAH) pathogenesis; however, the mechanism underlying neutrophil-induced injury in SAH remains obscure. This translational study aims to describe the patterns of intrahepatic neutrophil infiltration and its involvement in SAH pathogenesis. Immunohistochemistry analyses of explanted livers identified two SAH phenotypes despite a similar clinical presentation, one with high intrahepatic neutrophils (Neuhi), but low levels of CD8+ T cells, and vice versa. RNA-Seq analyses demonstrated that neutrophil cytosolic factor 1 (NCF1), a key factor in controlling neutrophilic ROS production, was upregulated and correlated with hepatic inflammation and disease progression. To study specifically the mechanisms related to Neuhi in AH patients and liver injury, we used the mouse model of chronic-plus-binge ethanol feeding and found that myeloid-specific deletion of the Ncf1 gene abolished ethanol-induced hepatic inflammation and steatosis. RNA-Seq analysis and the data from experimental models revealed that neutrophilic NCF1-dependent ROS promoted alcoholic hepatitis (AH) by inhibiting AMP-activated protein kinase (a key regulator of lipid metabolism) and microRNA-223 (a key antiinflammatory and antifibrotic microRNA). In conclusion, two distinct histopathological phenotypes based on liver immune phenotyping are observed in SAH patients, suggesting a separate mechanism driving liver injury and/or failure in these patients. 相似文献
999.
Malik Nassan Iyas Daghlas John W. Winkelman Hassan S. Dashti International Suicide Genetics Consortium Richa Saxena 《Neuropsychopharmacology》2022,47(9):1672
Insomnia and restless leg syndrome (RLS) are associated with increased risk for suicidal behavior (SB), which is often comorbid with mood or thought disorders; however, it is unclear whether these relationships are causal. We performed a two-sample Mendelian randomization study using summary-level genetic associations with insomnia symptoms and RLS against the outcomes of risk of major depressive disorder (MDD), bipolar disorder (BP), schizophrenia (SCZ), and SB. The inverse-variance weighted method was used in the main analysis. We performed replication and sensitivity analyses to examine the robustness of the results. We identified outcome cohorts for MDD (n = 170,756 cases/329,443 controls), BP (n = 20,352/31,358), SCZ (n = 69,369/236,642), SB-Cohort-2019 (n = 6569/14,996 all with MDD, BP or SCZ; and SB within individual disease categories), and SB-Cohort-2020 (n = 29,782/519,961). Genetically proxied liability to insomnia symptoms significantly associated with increased risk of MDD (odds ratio (OR) = 1.23, 95% confidence interval (CI) = 1.2–1.26, P = 1.37 × 10–61), BP (OR = 1.15, 95% CI = 1.07–1.23, P = 5.11 × 10–5), SB-Cohort-2019 (OR = 1.17, 95% CI = 1.07–1.27, P = 2.30 × 10–4), SB-Cohort-2019 in depressed patients (OR = 1.34, 95% CI = 1.16–1.54, P = 5.97 × 10–5), and SB-Cohort-2020 (OR = 1.24, 95% CI = 1.18–1.3, P = 1.47 × 10–18). Genetically proxied liability to RLS did not significantly influence the risk of any of the outcomes (all corrected P > 0.05). Results were replicated for insomnia with MDD and SB in Mass General Brigham Biobank and were consistent in multiple lines of sensitivity analyses. In conclusion, human genetic evidence supports for the first time a potentially independent and causal effect of insomnia on SB and encourages further clinical investigation of treatment of insomnia for prevention or treatment of SB.Subject terms: Genetic markers, Risk factors, Psychiatric disorders 相似文献
1000.
蓣知子皂甙IV的结构 总被引:5,自引:1,他引:5
从木通科木通属植物白木通[Akebia trifoliata(Thunb.)Koidz.var.australis(Diels)Rehd]种子的乙醇提取物中以硅胶层析等方法得四种三萜皂甙。其中甙IV是新天然产物,命名为蓣知子皂甙IV(yuzhiziosideIV)。根据化学和光谱分析,确定甙IV的结构为3-O-β-D-吡喃木糖基-(1→2)-a-L-吡喃阿拉伯糖齐墩果酸-28-O-β-D-吡喃葡萄糖基-(1→6)-β-D-吡喃葡萄糖酯甙。另外皂甙B(I)、皂甙C(II)和皂甙D(III)为已知物。这些化合物在白木通种子中均是首次得到。 相似文献