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61.
62.
Heart failure patients have abnormal cardiac high energy phosphate metabolism, the explanation for which is unknown. Patients with heart failure also have elevated plasma free fatty acid (FFA) concentrations. Elevated FFA levels are associated with increased cardiac mitochondrial uncoupling proteins (UCPs), which, in turn, are associated with decreased mitochondrial respiratory coupling and low cardiac efficiency. Here, we determined whether increased mitochondrial UCP levels contribute to decreased energetics in the failing heart by measuring UCPs and respiration in mitochondria isolated from the viable myocardium of chronically infarcted rat hearts and measuring efficiency (hydraulic work/O2 consumption) in the isolated, working rat heart. Ten weeks after infarction, cardiac levels of UCP3 were increased by 53% in infarcted, failing hearts that had ejection fractions less than 45%. Cardiac UCP3 levels correlated positively with non-fasting plasma FFAs (r = 0.81; p < 0.01). Mitochondria from failing hearts were less coupled than those from control hearts, as demonstrated by the lower ADP/O ratio of 1.9 ± 0.1 compared with 2.5 ± 0.2 in controls (p < 0.05). The decreased ADP/O ratio was reflected in an efficiency of 14 ± 2% in the failing hearts when perfused with 1 mM palmitate, compared with 20 ± 1% in controls (p < 0.05). We conclude that failing hearts have increased UCP3 levels that are associated with high circulating FFA concentrations, mitochondrial uncoupling, and decreased cardiac efficiency. Thus, respiratory uncoupling may underlie the abnormal energetics and low efficiency in the failing heart, although whether this is maladaptive or adaptive would require direct investigation.  相似文献   
63.
老鼠簕是一种重要的具海洋药用价值的红树林植物。以分光光度法(齐墩果酸为对照品,5%香草醛-冰醋酸和高氯酸为显色剂)测定红树植物老鼠簕中总三萜的含量。实验结果表明:在500nm波长条件下,齐墩果酸在0.04~0.20mg·mL-1范围内,0~60min间,吸光度与含量线性关系良好;首次测定得到,红树植物老鼠簕根的总三萜含量为0.62%,(RSD=0.91%,n=3);茎的总三萜含量为2.20%(RSD=3.94%,n=3);叶的总三萜含量为1.59%(RSD=5.04%,n=3)。  相似文献   
64.
65.
ABSTRACT: The retinoblastoma gene product is a nuclear phosphoprotein that undergoes cell cycle-dependent changes in its phosphorylation status. To analyze the expression of retinoblastoma gene product in the process of liver regeneration and the initiation of hepatocellular carcinoma, we studied immunohistochemically the expression of retinoblastoma gene product and DNA polymerase alpha (DPA) in 33 patients with various liver diseases. Only a few hepatocytes positive for retinoblastoma gene product were found in undamaged, nonregenerating liver tissues, whereas many hepatocytes positive for retinoblastoma gene product were detected in specimens of regenerating liver obtained from patients with acute or chronic liver diseases. Similarities were found between distribution patterns of hepatocytes positive for retinoblastoma gene product and those of hepatocytes positive for DPA, and a highly significant positive correlation was found between the number of hepatocyte nuclei stained for retinoblastoma gene product per 1000 nuclei examined (R-LI) and the number of hepatocyte nuclei stained for DPA per 1000 nuclei examined (D-LI) in tissues obtained from patients with nonmalignant liver disease. Hepatocellular carcinoma cells positive for DPA were detected in the 14 hepatocellular carcinoma specimens tested. In ten of these specimens, hepatocellular carcinoma cells positive for retinoblastoma gene product were found but not in the other four. For all hepatocellular carcinoma specimens, R-LI was proportional to D-LI. Thus in both nonmalignant and malignant liver, retinoblastoma gene product increased in proportion to proliferation of hepatocytes or hepatocellular carcinoma cells.  相似文献   
66.
Summative content analysis was used to define methods and heuristics from each case study. The review process was in two parts: (1) A literature review to identify conventional research methods and (2) a summative content analysis of published case studies, based on the identified methods and heuristics to suggest an order and priority of where and when were used. Over 200 research and design methods and design heuristics were identified. From the review of the 20 case studies 42 were identified as being applied. The majority of methods and heuristics were applied in phase two, market choice. There appeared a disparity between the limited numbers of methods frequently used, under 10 within the 20 case studies, when hundreds were available.
  • Implications for Rehabilitation
  • The communication highlights a number of issues that have implication for those involved in assistive technology new product development:

  • ?The study defined over 200 well-established research and design methods and design heuristics that are available for use by those who specify and design assistive technology products, which provide a comprehensive reference list for practitioners in the field;

  • ?The review within the study suggests only a limited number of research and design methods are regularly used by industrial design focused assistive technology new product developers; and,

  • ?Debate is required within the practitioners working in this field to reflect on how a wider range of potentially more effective methods and heuristics may be incorporated into daily working practice.

  相似文献   
67.
Introduction: In the past eight years, the European Association of Poisons Centres and Clinical Toxicologists (EAPCCT) has been intensively involved in a European Commission led process to develop EU legislation on the information of hazardous products that companies have to notify to EU Poisons Centres (or equivalent “appointed bodies”). As a result of this process, the Commission adopted Regulation (EU) No 2017/542, amending the CLP Regulation by adding an Annex on harmonised product submission requirements.

Harmonised mixture information requirements: Detailed and consistent information on the composition of the hazardous product will become available to EU Poisons Centres (PC). The information will be submitted by companies to PCs (or equivalent “appointed bodies”) using a web-based software application or in-house software. Two new important features are introduced. Firstly, to be able to rapidly identify the product formula, a Unique Formula Identifier (UFI) on the product label links to the submitted information. Secondly, for better comparability of reports on poisonings between EU member states, a harmonised Product Categorisation System will specify the intended use of a product. Rapid product identification and availability of detailed composition information will lead to timely and adequate medical intervention. This may lead to considerable reduction in healthcare costs.

Additionally, for companies trading across the EU, costs of submission of this information will be reduced significantly.

Next steps: From 2017, an implementation period has started, consisting of a three-year period for stakeholders to implement the new requirements, followed by a gradual applicability for consumer products (2020), professional products (2021) and industrial use-only products (2024). Technical tools to generate the electronic format and the UFI together with guidance documents are expected to be made available by the end of 2017 by the European Chemicals Agency (ECHA). Guidance on interpretation of legal text and ECHA helpdesk support are planned to be ready at the end of 2018.  相似文献   

68.
Objectives: Adiposity, defined by higher cardiometabolic index (CMI), lipid accumulation product (LAP), and body adiposity index (BAI), has conferred increased metabolic risk. However, the incremental utility of CMI, LAP, and BAI in association with prevalent hypertension has not been well described in a population-based setting. We hypothesized that CMI, LAP, and BAI would provide important insight into hypertension risk.

Methods: Blood pressure (BP), fasting lipid profiles, and anthropometric parameters were recorded in a cross-sectional study of 11,400 participants (mean age, 54 years; 53% women) from China. Logistic regression models were used to assess associations of CMI, LAP, and BAI with prevalent hypertension.

BAI was evaluated according to hip (cm)/[height (m)1.5]-18; LAP was calculated separately for men [(WC-65) × TG] and women [(WC-58) × TG]; and CMI was defined by TG/HDL-C × waist-to-height ratio.

Results: CMI, LAP, and BAI were independently correlated with higher SBP and DBP, with nonstandardized (B) coefficients ranging from 1.827 to 4.590 mmHg and 1.475 to 2.210 mmHg (all P < 0.001). After adjustment for hypertension risk factors and potential confounders, CMI, LAP, and BAI, modeled as continuous measures, carried hypertension odds (95% CI) of 1.356 (1.259–1.459), 1.631 (1.501–1.771), and 1.555 (1.454–1.662) in women, respectively, per SD increment. In men, each SD increase in CMI, LAP, and BAI experienced a 31%, 65%, and 53% higher hypertension risk, respectively. Moreover, among women, the odds ratio (95% CI) for hypertension were 2.318 (1.956–2.745), 3.548 (2.985–4.217), and 3.004 (2.537–3.557) in the 4th quartile vs the first quartile of CMI, LAP, and BAI, respectively. For men, the corresponding figures were 2.200 (1.838–2.635), 3.892 (3.238–4.677), and 3.288 (2.754–3.927), respectively.

Conclusion: Measurements of CMI, LAP, and BAI provide a more complete understanding of hypertension risk related to variation in body fat distribution and pinpoint hypertensive participants in great risk of cardiovascular disease in the future.  相似文献   

69.
Objectives: The objective of this paper was to evaluate the efficacy, duration of effect, and tolerability of SHP465 mixed amphetamine salts (MAS) extended-release versus placebo and immediate-release MAS (MAS IR) in adults with attention-deficit/hyperactivity disorder (ADHD).

Methods: Adults with ADHD Rating Scale, Version IV (ADHD-RS-IV) scores ≥24 were randomized to SHP465 MAS (50 or 75 mg), placebo, or 25 mg MAS IR in a double-blind, three-period, crossover study using a simulated adult workplace environment. On the final day of each 7-day treatment period, efficacy was assessed for 16 h postdose. Primary efficacy analyses for Permanent Product Measure of Performance (PERMP) total score averaged across all postdose assessments and each postdose time point were conducted in the intent-to-treat population using a mixed linear model. Secondary end-points included PERMP problems attempted and answered correctly and ADHD-RS-IV scores based on clinician ratings of counselor observations using the Time Segment Rating System and participant self-report. Tolerability assessments included treatment-emergent adverse events (TEAEs) and vital signs.

Results: Least squares mean (95% CI) treatment differences (combined 50/75 mg SHP465 MAS–placebo) significantly favored SHP465 MAS over placebo for PERMP total score averaged across all postdose assessments (18.38 [11.28, 25.47]; < .0001) and at each postdose assessment (all < .02). Nominal superiority of MAS IR over placebo for PERMP total score averaged across all postdose assessments was observed (nominal = .0001); treatment differences between SHP465 MAS and MAS IR were not significant (nominal = .2443). The two most frequently reported TEAEs associated with SHP465 MAS were insomnia (36.5%) and anorexia (21.2%). Mean increases in pulse and blood pressure with SHP465 MAS exceeded those of placebo.

Conclusions: SHP465 MAS (combined 50/75 mg) significantly improved PERMP total score versus placebo, with superiority observed from 2 to 16 h postdose. The tolerability profile of SHP465 MAS was similar to previous reports of SHP465 MAS in adults with ADHD.

Clinical trial registration: https://clinicaltrials.gov/ct2/show/NCT00928148 identifier is NCT00928148.  相似文献   

70.
Distortion product otoacoustic emission (DPOAE) level mapping provides a comprehensive picture of cochlear responses over a range of DP frequencies and f2/f1 ratios. We hypothesized that individuals exposed to high-level sound would show changes detectable by DPOAE mapping, but not apparent on a standard DP-gram. Thirteen normal hearing subjects were studied before and after attending music concerts. Pure-tone audiometry (500-8,000 Hz), DP-grams (0.3-10 kHz) at 1.22 ratio, and DPOAE level maps were collected prior to, as soon as possible after, and the day after the concerts. All maps covered the range of 2,000-6,000 Hz in DP frequency and from 1.3 to -1.3 in ratio using equi-level primary tone stimuli. Changes in the pure-tone audiogram were significant (P ≤ 0.01) immediately after the concert at 1,000 Hz, 4,000 Hz, and 6,000 Hz. The DP-gram showed significant differences only at f2 = 4,066 (P = 0.01) and f2 = 4,348 (P = 0.04). The postconcert changes were readily apparent both visually and statistically (P ≤ 0.01) on the mean DP level maps, and remained statistically significantly different from baseline the day after noise exposure although no significant changes from baseline were seen on the DP-gram or audiogram the day after exposure. Although both the DP-gram and audiogram showed recovery by the next day, the average DPOAE level maps remained significantly different from baseline. The mapping data showed changes in the cochlea that were not detected from the DP-gram obtained at a single ratio. DPOAE level mapping provides comprehensive information on subtle cochlear responses, which may offer advantages for studying and tracking noise-induced hearing loss (NIHL).  相似文献   
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