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61.

Aim

Tenascin C (TNC) is a large extracellular matrix glycoprotein. It is involved in development and upregulated both during tissue repair and in several pathological conditions, including cardiovascular disease. Extracellular matrix proteins play a role in promoting exercise responses, leading to adaptation, regeneration, and repair. The main goal of this study was to investigate whether a short anaerobic effort leads to increased levels of TNC in serum.

Methods

Thirty-nine healthy men performed a Wingate test followed by a muscle biopsy. Myoblasts were isolated from the muscle biopsies and differentiated to myotubes ex vivo. TNC RNA was quantified in the biopsies, myotubes and myoblasts using RNA sequencing. Blood samples were drawn before and 5 min after the Wingate test. Serum TNC levels were measured using enzyme-linked immunosorbent assay.

Results

After the Wingate test, serum TNC increased on average by 23% [15–33], median [interquartile range]; PWilcoxon < 0.0001. This increase is correlated with peak power output and power drop, but not with VO2max. TNC RNA expression is higher in myoblasts and myotubes compared to skeletal muscle tissue.

Conclusion

TNC is secreted systemically as a response to the Wingate anaerobic test in healthy males. The response was positively correlated with peak power and power drop, but not with VO2max which implicates a relation to mechanical strain and/or blood flow. With higher expression in undifferentiated myoblast cells than muscle tissue, it is likely that TNC plays a role in muscle tissue remodelling in humans. Our findings open for research on how TNC contributes to exercise adaptation.  相似文献   
62.
Theiler’s murine encephalomyelitis virus (TMEV) induces demyelination in susceptible strains of mice (SJL/J) through an immunopathological process that is mediated by CD4+ Th1 T cell. These T cells are chemoattracted to the central nervous system by chemokines. Hence, in this study, we focused on the production of the chemokine “interferon-gamma-inducible protein 10 kDa,” or IP-10/CXCL10, by cultured SJL/J mouse astrocytes infected with the BeAn strain of TMEV and its capacity to attract activated T cells. The analysis of the whole murine genome by DNA hybridization with cRNAs from mock- and TMEV-infected cultures revealed the upregulation of six sequences that potentially encode for CXCL10. This increased CXCL10 expression was validated by PCR and qPCR. The presence of this chemokine was further demonstrated by enzyme-linked immunoassay (ELISA). Significantly, astrocytes from BALB/c mice, a strain resistant to demyelination, did not produce CXCL10. The secreted CXCL10 was biologically active, inducing chemoattraction of activated lymphocytes. The inflammatory cytokines, IL-1α, IFN-γ, and TNF-α, were strong inducers of CXCL10 in astrocytes. Serum from TMEV-infected SJL/J but not BALB/c mice contains CXCL10, the levels of which peak at the onset of the clinical disease. Finally, this in vitro inflammation model was fully inhibited by 17β-estradiol and four selective estrogen receptor modulators, as demonstrated by ELISA and qPCR.  相似文献   
63.

Purpose

We report a 45-year old female adult patient with terminal deletion of chromosome 11q resulting in clinical phenotype of late-onset combined immunodeficiency.

Methods

We describe the clinical phenotype and discuss the similarities between our patient and those with chromosome 22q11.2 deletion syndrome. Immunological evaluation included immunoglobulin levels, vaccine responses, number and function of T, NK and B cell subsets and comparative genomic hybridization test of blood and fibroblasts.

Results

The patient suffered from recurrent pneumococcal pneumonia and genital and cutaneous condylomas. She had a history of learning difficulties, dysmorphic features, autoimmune thyroiditis, chronic thrombocytopenia and severe asthma. We found Paris-Trousseau type thrombocytopenia, B-, T- and NK-lymphopenia, T cell oligoclonality and IgG hypogammaglobulinemia with inability to respond to pneumococcal polysaccharide, tetanus and diphtheria vaccines. A terminal deletion of chromosome 11q compatible with partial Jacobsen syndrome was found.

Conclusions

This confirms Jacobsen syndrome as a chromosome deletion syndrome able to cause combined immunodeficiency.  相似文献   
64.
This study reports the electropolymerization of novel keto functionalized octaethyl metal porphyrins (Zn2+ and Ni2+) in the presence of 4,4′-bipyridine (4,4′-bpy) as a bridging nucleophile. The polymer films were characterized by electrochemical, spectroscopic (UV-Vis, XPS, FT-IR and Raman spectroscopy) and imaging (AFM and SEM) techniques. The absorption and electronic spectra confirm the presence of both porphyrin and 4,4′-bipyridine units in the film. The surface morphology reveals homogeneous film deposition with average roughness values of approx. 8 nm. The theoretical studies performed offered insights into the interplay of different metal centres (Zn2+ and Ni2+) and the keto functionality of the porphyrin unit in the formation of copolymer films. The electrochemical interaction of polymer films with CO2 suggests a reversible trap and release of CO2 with low energy barriers for both the polymers.

Electropolymerization of keto functionalized porphyrins and 4,4′-bipyridine.  相似文献   
65.
Open in a separate windowOBJECTIVESWe investigated whether the selective use of supracoronary ascending aorta replacement achieves late outcomes comparable to those of aortic root replacement for acute Stanford type A aortic dissection (TAAD).METHODSPatients who underwent surgery for acute type A aortic dissection from 2005 to 2018 at the Helsinki University Hospital, Finland, were included in this analysis. Late mortality was evaluated with the Kaplan–Meier method and proximal aortic reoperation, i.e. operation on the aortic root or aortic valve, with the competing risk method.RESULTSOut of 309 patients, 216 underwent supracoronary ascending aortic replacement and 93 had aortic root replacement. At 10 years, mortality was 33.8% after aortic root replacement and 35.2% after ascending aortic replacement (P = 0.806, adjusted hazard ratio 1.25, 95% confidence interval, 0.77–2.02), and the cumulative incidence of proximal aortic reoperation was 6.0% in the aortic root replacement group and 6.2% in the ascending aortic replacement group (P = 0.65; adjusted subdistributional hazard ratio 0.53, 95% confidence interval 0.15–1.89). Among 71 propensity score matched pairs, 10-year survival was 34.4% after aortic root replacement and 36.2% after ascending aortic replacement surgery (P = 0.70). Cumulative incidence of proximal aortic reoperation was 7.0% after aortic root replacement and 13.0% after ascending aortic replacement surgery (P = 0.22). Among 102 patients with complete imaging data [mean follow-up, 4.7 (3.2) years], the estimated growth rate of the aortic root diameter was 0.22 mm/year, that of its area 7.19 mm2/year and that of its perimeter 0.43 mm/year.CONCLUSIONSWhen stringent selection criteria were used to determine the extent of proximal aortic reconstruction, aortic root replacement and ascending aortic replacement for type A aortic dissection achieved comparable clinical outcomes.  相似文献   
66.
Dr. S. M. Virtanen  T. Saukkonen  E. Savilahti  K. Ylönen  L. Räsänen  A. Aro  M. Knip  J. Tuomilehto  H. K. Åkerblom  R. Lounamaa  L. Toivanen  E. A. Kaprio  J. Pitkäniemi  E. Virtala  A. Fagerlund  M. v. Flittner  B. Gustafsson  C. Häggqvist  A. Hakulinen  L. Herva  P. Hiltunen  T. Huhtamäki  N. -P. Huttunen  T. Huupponen  M. Hyttinen  T. Joki  R. Jokisalo  M. -L. Käär  S. Kallio  U. Kaski  L. Laine  J. Lappalainen  J. Mäenpää  A. -L. Mäkelä  K. Niemi  A. Niiranen  P. Ojajärvi  T. Otonkoski  K. Pihlajamäki  S. Pöntynen  J. Rajantie  J. Sankala  J. Schumacher  M. Sillanpää  M. -R. Ståhlberg  C. -H. Stråhlmann  T. Uotila  M. Väre  P. Varimo 《Diabetologia》1994,37(4):381-387
Summary Associations of infant feeding patterns and milk consumption with cow's milk protein antibody titres were studied in 697 newly-diagnosed diabetic children, 415 sibling-control children and 86 birth-date-and sex-matched population-based control children in the nationwide Childhood Diabetes in Finland study. IgA and IgG antibody titres to the proteins of cow's milk formula, BLG and BSA, and IgM antibody titres to cow's milk formula proteins were measured by ELISA. Several inverse correlations were observed between the duration of breast-feeding or age at introduction of dairy products and antibody titres, and positive correlations were observed between milk consumption and antibody titres in all three populations studied. Multivariate analyses which included the infant feeding variables, milk consumption and current age simultaneously showed that the earlier the introduction of dairy products and the greater the consumption of milk was, the higher several antibody titres were. High IgA antibody titres to cow's milk formula were associated with a greater risk of IDDM both among diabeticpopulation-control and diabetic-sibling-control pairs when adjusted for other cow's milk antibody titres, dietary variables and in diabetic-sibling-control pairs also for ICA. The results suggest that young age at introduction of dairy products and high milk consumption during childhood increase the levels of cow's milk antibodies and that high IgA antibodies to cow's milk formula are independently associated with increased risk of IDDM.Abbreviations IDDM Insulin-dependent diabetes mellitus - BLG betalactoglobulin - BSA bovine serum albumin - ICA islet cell antibodies - IAA insulin autoantibodies - OR odds ratio - CI confidence interval  相似文献   
67.
The prevalence of shift work disorder (SWD) has been studied using self‐reported data and the International Classification of Sleep Disorders, Second Edition (ICSD‐2) criteria. We examined the prevalence in relation to ICSD‐2 and ICSD‐3 criteria, work schedules and the number of non‐day shifts (work outside 06:00–18:00 hours) using objective working‐hours data. Secondly, we explored a minimum cut‐off for the occurrence of SWD symptoms. Hospital shift workers without (n = 1,813) and with night shifts (n = 2,917) and permanent night workers (n = 84) answered a survey (response rate 69%) on SWD and fatigue on days off. The prevalence of SWD was calculated for groups with ≥1, ≥3, ≥5 and ≥7 monthly non‐day shifts utilizing the working hours registry. ICSD‐3‐based SWD prevalence was 2.5%–3.7% (shift workers without nights), 2.6%–9.5% (shift workers with nights) and 6.0% (permanent night workers), depending on the cut‐off of non‐day shifts (≥7–1/month, respectively). The ICSD‐2‐based prevalence was higher: 7.1%–9.2%, 5.6%–33.5% and 16.7%, respectively. The prevalence was significantly higher among shift workers with than those without nights (p‐values <.001) when using the cut‐offs of ≥1–3 non‐day shifts. Shift workers with nights who had ≥3 days with ICSD‐3‐based SWD symptoms/month more commonly had fatigue on days off (49.3%) than those below the cut‐off (35.8%, p < .05). The ICSD‐3 criteria provided lower estimates for SWD prevalence than ISCD‐2 criteria, similarly to exclusion of employees with the fewest non‐day shifts. The results suggest that a plausible cut‐off for days with ICSD‐3‐based SWD symptoms is ≥3/month, resulting in 3%–6% prevalence of SWD.  相似文献   
68.
A key question in precision medicine is how functional heterogeneity in solid tumours informs therapeutic sensitivity. We demonstrate that spatial characteristics of oncogenic signalling and therapy response can be modelled in precision‐cut slices from Kras‐driven non‐small‐cell lung cancer with varying histopathologies. Unexpectedly, profiling of in situ tumours demonstrated that signalling stratifies mostly according to histopathology, showing enhanced AKT and SRC activity in adenosquamous carcinoma, and mitogen‐activated protein kinase (MAPK) activity in adenocarcinoma. In addition, high intertumour and intratumour variability was detected, particularly of MAPK and mammalian target of rapamycin (mTOR) complex 1 activity. Using short‐term treatment of slice explants, we showed that cytotoxic responses to combination MAPK and phosphoinositide 3‐kinase–mTOR inhibition correlate with the spatially defined activities of both pathways. Thus, whereas genetic drivers determine histopathology spectra, histopathology‐associated and spatially variable signalling activities determine drug sensitivity. Our study is in support of spatial aspects of signalling heterogeneity being considered in clinical diagnostic settings, particularly to guide the selection of drug combinations. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
69.
BACKGROUND: Pravastatin is a widely used statin in adults, but its pharmacokinetics in children is not known. Our aim was to determine the single-dose pharmacokinetics and the lipid-lowering effect and safety of short-term administration of pravastatin in children. METHODS: Twenty children (age range, 4.9-15.6 years) with heterozygous familial hypercholesterolemia ingested a single dose of 10 mg pravastatin. Plasma concentrations of pravastatin were measured for up to 10 hours. The patients then took 10 mg pravastatin orally once daily for 8 weeks. The concentration of serum lipids and safety laboratory parameters were measured before and after 8 weeks of treatment. RESULTS: The mean peak plasma concentration (C(max)) of pravastatin was 15.7 ng/mL (range, 1.6-55.0 ng/mL), and the mean time to reach C(max) was 1.4 hours (range, 0.5-4 hours). The mean elimination half-life of pravastatin was 1.6 hours (range, 0.85-4.2 hours). The area under the plasma concentration-time curve of pravastatin ranged from 5.7 to 58.9 ng. h/mL (mean value, 26.6 ng. h/mL). By 8 weeks of treatment, the serum concentration of total cholesterol had decreased 18% (P <.0001); low-density lipoprotein cholesterol, 21% (P <.0001); and triglycerides, 18% (not significant, P =.18). The concentration of high-density lipoprotein cholesterol had increased 8% (not significant, P =.13). Few transient adverse events occurred. No increases in serum alanine aminotransferase, creatine kinase, or creatinine level were observed. CONCLUSIONS: The pharmacokinetic and pharmacodynamic profile of pravastatin in children is similar to that reported for adults. In the short term, the daily dose of 10 mg pravastatin was well tolerated and moderately effective in decreasing the serum cholesterol concentration. However, further studies are needed on the long-term safety and efficacy of pravastatin in children.  相似文献   
70.
To study the effect of controlled heavy drinking of 60 g ethanol/day for 3 weeks on carbohydrate-deficient transferrin (CDT), a commercial double antibody kit (CDTect™) was used. By the end of the third drinking week, a statistically significant increase in the mean CDT level was observed. When compared to AST and γ-glutamyltransferase, CDT was a more informative marker. However, only in 2 of the 10 volunteers did CDT exceed the upper normal level (20 units/liter) recommended by the manufacturer. This indicates that the sensitivity of CDT to detect heavy drinking is lower than that previously reported. The higher accuracy has in general been obtained in studies comparing healthy controls with a low alcohol consumption to alcoholics with an alcohol consumption higher than that used in the present experiment. Our results suggest that it remains to be established whether CDT, although better than AST and γ-glutamyltransferase, will provide a clinically useful tool in identifying heavy drinkers in populations covering a wide range of alcohol consumption.  相似文献   
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