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121.
Interferon-alpha (IFN-alpha) is a pleiotropic cytokine that has antiviral, antiproliferative, and immunoregulatory functions. There is increasing evidence that IFN-alpha has an important role in T-cell biology. We have analyzed the expression of IL-2Ralpha, c-myc, and pim-1 genes in anti-CD3-activated human T lymphocytes. The induction of these genes is associated with interleukin-2 (IL-2)-induced T-cell proliferation. Treatment of T lymphocytes with IFN-alpha, IL-2, IL-12, and IL-15 upregulated IL-2Ralpha, c-myc, and pim-1 gene expression. IFN-alpha also sensitized T cells to IL-2-induced proliferation, further suggesting that IFN-alpha may be involved in the regulation of T-cell mitogenesis. When we analyzed the nature of STAT proteins capable of binding to IL-2Ralpha, pim-1, and IRF-1 GAS elements after cytokine stimulation, we observed IFN-alpha-induced binding of STAT1, STAT3, and STAT4, but not STAT5 to all of these elements. Yet, IFN-alpha was able to activate binding of STAT5 to the high-affinity IFP53 GAS site. IFN-alpha enhanced tyrosine phosphorylation of STAT1, STAT3, STAT4, STAT5a, and STAT5b. IL-12 induced STAT4 and IL-2 and IL-15 induced STAT5 binding to the GAS elements. Taken together, our results suggest that IFN-alpha, IL-2, IL-12, and IL-15 have overlapping activities on human T cells. These findings thus emphasize the importance of IFN-alpha as a T-cell regulatory cytokine. 相似文献
122.
Kauko Ojala MD Martti Sorri Pekka Sipilä Juhani Vainio-Matila 《European archives of oto-rhino-laryngology》1981,233(3):251-260
Summary The long-term hearing results are presented for 135 ears operated on radically. In 59 of the ears temporary paraffin filling of the tympanic cavity was employed after the removal of the typanic mucosa at operation. The filling material was removed, and the ossiculoplasty was performed about 6 months later. In 76 ears a one-stage operation with tympanoplasty and Silastic sheeting was employed.There were no statistical differences between the groups of ears mentioned according to hearing results early (1 year) or late (5–14 years) postoperatively or in the deterioration of the air-bone gaps after the first postoperative year (P>0.05). The late change in the air-bone gap was significant in both groups (paraffin group: 6.1 dB; Silastic sheeting group: 5.7 dB; P<0.05). The total improvement of hearing late after surgery (as compared to the preoperative hearing) was significantly better in the paraffin group than in ears with Silastic sheeting (P<0.05). Paraffinplasty seems to be a suitable way to avoid tympanic adhesions. 相似文献
123.
Antti Saraste MD PhD Sami Kajander MD PhD Chunlei Han MD PhD Sergey V. Nesterov MD PhD PMP Juhani Knuuti MD PhD 《Journal of nuclear cardiology》2012,19(5):1044-1059
Positron emission tomography (PET) enables quantitative measurements of myocardial blood flow (MBF) and myocardial flow reserve (MFR). Recent developments and improved availability of PET technology have resulted in growing interest in translation of quantitative flow analysis from mainly a research tool to routine clinical practice. Quantitative PET measurements of absolute MBF and MFR have potential to improve accuracy of myocardial perfusion imaging in diagnosis of multivessel coronary artery disease as well as definition of the extent and functional importance of stenoses. This article reviews recent advances and experience in the quantitative myocardial perfusion imaging together with issues that need to be resolved for quantitative analysis to become clinical reality. 相似文献
124.
Antti E. Vento M.D. O. Juhani Rämö M.D. Ph.D. Eero J. Pesonen M.D. Lasse Heikkilä M.D. Ph.D. Erkki Nissinen Ph.D. Aila Holopainen MSc. Severi P. Mattila M.D. Ph.D. 《The International journal of angiology》1999,8(1):16-21
During aortic cross-clamping, the myocardium suffers from global ischemia, which is followed by reperfusion after declamping. The generation of free oxygen radicals increases during reperfusion, resulting in arrhythmias and impaired cardiac function. This study was conducted to evaluate the effect of a novel antioxidant nitecapone (NC) on cardiac reperfusion injuryin vivo. Twelve pigs were anesthetized and after sternotomy the aorta and the right atrium were cannulated for cardiopulmonary bypass. The heart was arrested with either +4°C crystalloid cardioplegia alone in the control group (n=6) or cardioplegia with NC (50 µM) added in the NC group (n=6). Cardioplegia was added every 20 minutes. After 1 hour of aortic crossclamping, blood samples for oxidative stress analysis were taken, and hemodynamic profile surveillance continued for 90 minutes. Heart rate (p=0.04) and left ventricular end diastolic pressure (LVEDP) (p=0.04) were significantly lower in the NC group than in the C group after aortic declamping. Cardiac output and myocardial contractility (dP/dtmax) were also enhanced in the group receiving NC, but the difference was not statistically significant. At 30 minutes after reperfusion, the coronary production (coronary sinus-aorta) of thiobarbituric acid reactive substances correlated inversely with cardiac output (r=–0.90,p=0.001) and stroke volume (r=–0.82,p=0.007). The effect of NC on lipid peroxidation seems to be modest and therefore the target of NC is unclear. NC would appear, however, to be a beneficial additive in the crystalloid cardioplegia in terms of functional recovery. 相似文献
125.
Oliver Lindner Thomas N. B. Pascual Mathew Mercuri Wanda Acampa Wolfgang Burchert Albert Flotats Philipp A. Kaufmann Anastasia Kitsiou Juhani Knuuti S. Richard Underwood João V. Vitola John J. Mahmarian Ganesan Karthikeyan Nathan Better Madan M. Rehani Ravi Kashyap Maurizio Dondi Diana Paez Andrew J. Einstein for the INCAPS Investigators Group 《European journal of nuclear medicine and molecular imaging》2016,43(4):718-728
Purpose
Nuclear cardiology is widely used to diagnose coronary artery disease and to guide patient management, but data on current practices, radiation dose-related best practices, and radiation doses are scarce. To address these issues, the IAEA conducted a worldwide study of nuclear cardiology practice. We present the European subanalysis.Methods
In March 2013, the IAEA invited laboratories across the world to document all SPECT and PET studies performed in one week. The data included age, gender, weight, radiopharmaceuticals, injected activities, camera type, positioning, hardware and software. Radiation effective dose was calculated for each patient. A quality score was defined for each laboratory as the number followed of eight predefined best practices with a bearing on radiation exposure (range of quality score 0 – 8). The participating European countries were assigned to regions (North, East, South, and West). Comparisons were performed between the four European regions and between Europe and the rest-of-the-world (RoW).Results
Data on 2,381 European patients undergoing nuclear cardiology procedures in 102 laboratories in 27 countries were collected. A cardiac SPECT study was performed in 97.9 % of the patients, and a PET study in 2.1 %. The average effective dose of SPECT was 8.0?±?3.4 mSv (RoW 11.4?±?4.3 mSv; P?<?0.001) and of PET was 2.6?±?1.5 mSv (RoW 3.8?±?2.5 mSv; P?<?0.001). The mean effective doses of SPECT and PET differed between European regions (P?<?0.001 and P?=?0.002, respectively). The mean quality score was 6.2?±?1.2, which was higher than the RoW score (5.0?±?1.1; P?<?0.001). Adherence to best practices did not differ significantly among the European regions (range 6 to 6.4; P?=?0.73). Of the best practices, stress-only imaging and weight-adjusted dosing were the least commonly used.Conclusion
In Europe, the mean effective dose from nuclear cardiology is lower and the average quality score is higher than in the RoW. There is regional variation in effective dose in relation to the best practice quality score. A possible reason for the differences between Europe and the RoW could be the safety culture fostered by actions under the Euratom directives and the implementation of diagnostic reference levels. Stress-only imaging and weight-adjusted activity might be targets for optimization of European nuclear cardiology practice.126.
Magnetocardiographic indices of left ventricular hypertrophy 总被引:1,自引:0,他引:1
Karvonen M Oikarinen L Takala P Kaartinen M Rossinen J Hänninen H Montonen J Nenonen J Mäkijärvi M Keto P Toivonen L Nieminen MS Katila T 《Journal of hypertension》2002,20(11):2285-2292
OBJECTIVE: We tested the hypothesis that multichannel magnetocardiographic (MCG) mapping can detect and quantify the degree of left ventricular hypertrophy (LVH). DESIGN: A cross-sectional study. SETTING: Helsinki University Central Hospital, a tertiary referral center. PARTICIPANTS: Forty-two patients with pressure overload induced LVH by gender-specific echocardiographic criteria (LVH group), and 12 healthy middle-aged controls. MAIN OUTCOME MEASURES: MCG QRS-T area integrals and QRS-T angle in magnetic field maps in relation to echocardiographic LVH as well as left ventricular (LV) mass and structure. Conventional 12-lead electrocardiographic (ECG) LVH indices (Sokolow-Lyon voltage, Cornell voltage, Cornell voltage duration product) were assessed for comparison. RESULTS: MCG QRS- and T-wave integrals provided complementary information of echocardiographic LV mass. Their combination, the QRS-T integral, and the QRS-T angle were increased in patients with LVH and, in those patients, correlated significantly with LV mass indexed to body surface area (r = 0.455;P = 0.002 and r= 0.379; P= 0.013, respectively). A QRS-T integral 16000 fT.s had identical sensitivity of 62% at 92% specificity as the gender-adjusted Cornell voltage duration product of 240 micro V.s for the detection of LVH. CONCLUSIONS: The MCG method can detect patients with LVH and also quantify the degree of LVH in patients with increased LV mass. 相似文献
127.
Koskela RM Karttunen TJ Niemelä SE Lehtola JK Ilonen J Karttunen RA 《European journal of gastroenterology & hepatology》2008,20(4):276-282
OBJECTIVES: Coeliac disease (CD) is common in patients with microscopic colitis (MC). The human leucocyte antigen (HLA)-DR3-DQ2 haplotype is strongly associated with CD, and there is evidence for an association with MC. We analysed the genetic background of MC by assessing the haplotypes of HLA-DR3-DQ2 and HLA-DR4-DQ8. In addition, TNFalpha gene polymorphism (-308) associated with susceptibility to several autoimmune diseases was studied. METHODS: Eighty patients with MC including 29 with collagenous colitis (CC) and 51 with lymphocytic colitis (LC) were typed for HLA-DR3-DQ2, and HLA-DR4-DQ8 molecule encoding genes using either an allele-specific PCR, or hybridization with sequence-specific oligonucleotides. Duodenal biopsies (N=78) confirmed the diagnosis of CD in 15 (18.8%) patients. TNFalpha(308) alleles were analyzed in 78 patients with MC (27 with CC and 51 with LC). A control group of 3627 patients was used in the HLA study and 178 patients in the TNFalpha study. RESULTS: HLA-DR3-DQ2 haplotype was more frequent in patients with MC (43.8%) including both subgroups (LC, 44.8%; CC, 43.1%; P<0.001), and MC with CD (86.7%; P<0.001) and without CD (33.3%; P=0.003), compared with the controls (18.1%). Similarly, the TNF2 carrier rate was higher in MC (46.2%; P<0.001) including both CC (44.4%; P=0.031) and LC (47.1%; P=0.001), and both MC patients with CD (66.7%; P=0.001) and without CD (39.3%; P=0.019), compared with the controls (23%). CONCLUSION: Both CC and LC are associated with the HLA-DR3-DQ2 haplotype and with TNF2 allele carriage. These associations are present also in MC patients without CD. The shared predisposing HLA-DR3-DQ2 haplotype and the high prevalence of CD in patients with MC suggest an epidemiological overlap, and probably some similarities in the pathogenesis of CD and MC. 相似文献
128.
BackgroundAvian influenza A(H5N1) viruses have caused sporadic infections in humans and thus they pose a significant global health threat. Among symptomatic patients the case fatality rate has been ca. 50%. H5N1 viruses exist in multiple clades and subclades and several candidate vaccines have been developed to prevent A(H5N1) infection as a principal measure for preventing the disease.MethodsSerum antibodies against various influenza A(H5N1) clade viruses were measured in adults by ELISA-based microneutralization and haemagglutination inhibition tests before and after vaccination with two different A(H5N1) vaccines in 2009 and 2011.ResultsTwo doses of AS03-adjuvanted A/Indonesia/5/2005 vaccine induced good homologous but poor heterologous neutralizing antibody responses against different clade viruses. However, non-adjuvanted A/Vietnam/1203/2004 booster vaccination in 2011 induced very strong and long-lasting homologous and heterologous antibody responses while homologous response remained weak in naïve subjects.ConclusionsSequential vaccination with two different A(H5N1) pre-pandemic vaccines induced long-lasting high level cross-clade immunity against influenza A(H5N1) strains, thus supporting a prime-boost vaccination strategy in pandemic preparedness plans. 相似文献
129.
Elina V Juhani L Tiina TJ Kari M Irma V Mauri I Harri H Esko K Hannu H Santero K Jukka V 《Journal of health organization and management》2006,20(2-3):85-94
PURPOSE: This paper describes factors influencing doctor-managers' decision making in specialised health care, health centres and at different levels of management. DESIGN/METHODOLOGY/APPROACH: Data were collected as part of a survey on physicians graduating in 1977-1991 as drawn from the register of the Finnish Medical Association. The study sample was formed by selecting all physicians born on odd days (n=4144) from the baseline group (n=8232). The category of doctor-managers comprised physicians reporting as their main occupation: principal or assistant principal physician of hospital, medical director or principal physician of health centre, senior ward physician of hospital, and health centre physician in charge of a population area. FINDINGS: Independent of gender, all doctor-managers responding to the survey reported that the most important base for decision making was personal professional experience. Position in organisation (first-line manager, principal physician) had no impact on the base of decision making. Doctor-managers in primary health care utilised knowledge on norms and knowledge available from their organisation in support of their decision making to a greater degree compared with doctor-managers in specialised health care. RESEARCH IMPLICATIONS: Evolution discourse from public administration is not yet receiving much response in Finnish doctor-managers' activities, instead, they still act as clinicians. ORIGINALITY/VALUE: Facing the growing challenges of the future, the paper shows that doctor-managers should reconstruct their orientation and to act more like managers. 相似文献
130.
Strikingly homologous immunoglobulin gene rearrangements and poor outcome in VH3-21-using chronic lymphocytic leukemia patients independent of geographic origin and mutational status 总被引:5,自引:0,他引:5 下载免费PDF全文
Thorsélius M Kröber A Murray F Thunberg U Tobin G Bühler A Kienle D Albesiano E Maffei R Dao-Ung LP Wiley J Vilpo J Laurell A Merup M Roos G Karlsson K Chiorazzi N Marasca R Döhner H Stilgenbauer S Rosenquist R 《Blood》2006,107(7):2889-2894
We recently reported that Swedish VH3-21-using chronic lymphocytic leukemia (CLL) patients showed restricted immunoglobulin gene features and poor prognosis despite VH mutation status. To investigate this further, we analyzed the VH and VL gene rearrangements in 90 VH3-21+ patients from Sweden, Germany, Italy, United States, Finland, and Australia and correlated these data with survival and other prognostic markers. Sixty-three percent exhibited mutated VH genes and 37% unmutated VH genes. Fifty (56%) patients displayed a short and homologous heavy-chain CDR3, many of these with the amino acid motif DANGMDV. Also, a highly biased V2-14 use was evident in 72% of patients with a restricted light-chain CDR3, QVWDS(S/G)SDHPWV. Combined restricted heavy- and light-chain CDR3s were found in patients from all included countries. Although VH3-21+ CLLs have a remarkably predominant expression, analyses of kappa deleting element indicated a conserved light-chain rearrangement order. The overall survival was poor in the VH3-21+ cohort (median survival, 88 months), with no significant difference in relation to mutation status or CDR3 homology. High ZAP-70 and CD38 expression was found in both mutated and unmutated VH3-21+ cases as well as a slight increase of 11q-aberrations. In summary, highly restricted B-cell receptors and worse outcome characterize VH3-21+ CLLs independent of geographic origin and mutation status. 相似文献