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91.
92.
We prospectively investigated the risk of early atherosclerosis, by classical cardiovascular risk factors and intima-media thickness (IMT) at the common carotid arteries, in 23 adolescents diagnosed as GH deficient (GHD) during childhood and in 23 healthy sex-, age-, and BMI-matched controls. Measurements were performed in all subjects before stopping GH replacement. Because the diagnosis of GHD had been confirmed in 15 of the 23 adolescents, the protocol changed according to the diagnosis as follows: measurements were repeated after 6 months of GH withdrawal and 6 months of GH reinstitution in the 15 with GHD, and after 6 and 12 months of GH withdrawal, measurements were also taken in the eight non-GHD subjects. Serum IGF-I levels were in the normal range for age in all patients before GH withdrawal. When compared with controls, before GH withdrawal, GHD adolescents had reduced high-density lipoprotein cholesterol levels and increased total/high-density lipoprotein cholesterol ratio, fibrinogen, low-density lipoprotein cholesterol, and glucose levels; non-GHD adolescents had increased glucose, insulin, and homeostasis model assessment score. IMT at the common carotid arteries was similar in GHD and controls (0.52 +/- 0.03 vs. 0.55 +/- 0.06 mm; P = 0.23) and was higher in non-GHD than in controls (0.62 +/- 0.03 vs. 0.54 +/- 0.06 mm; P = 0.01). In GHD adolescents, 6 months of GH treatment withdrawal and 6 months of GH treatment reinstitution modified IGF-I levels, lipid profile, and insulin resistance but not IMT or systolic and diastolic peak velocities at the common carotid arteries. In non-GHD subjects, 12 months of GH treatment withdrawal significantly decreased IGF-I levels, IMT (to 0.54 +/- 0.06 mm; P < 0.001 vs. baseline), systolic and diastolic peak velocities, and improved insulin resistance. In conclusion, the discontinuation of GH in confirmed GHD adolescents is not followed by significant alterations of the common carotid arteries, despite the profound negative alterations of the lipid profile. In adolescents who were not confirmed to have GHD, IMT was increased while on GH therapy and normalized when they were taken off of GH.  相似文献   
93.
Background: New drugs for the treatment of diabetes, glucagon‐like peptide‐1 (GLP‐1) receptor agonists and inhibitors of dipeptidyl peptidase‐4 (DPP‐4) have shown pleiotropic effects on bone metabolism and anti‐inflammatory properties. The aim of this study is to evaluate the effects of exenatide (GLP‐1 agonist) and sitagliptin (DPP‐4 inhibitor) during periodontitis induction by ligature insertion in rats. Methods: Forty rats were divided into four groups: 1) animals with induced periodontitis that received exenatide (EG); 2) animals with induced periodontitis that received sitagliptin (SG); 3) animals with induced periodontitis and without drug treatment (LG); and 4) animals without induced periodontitis and without drug treatment (controls). The drugs were administered for 28 days. On the day the animals were sacrificed, blood was collected for analysis of glucose and DPP‐4 levels. The gene expressions of prostaglandin‐endoperoxide synthase 2, tissue inhibitor of metalloproteinase 1, Dpp4, nitric oxide synthase 2 (Nos2), interleukin 1β (Il1b), and matrix metalloproteinase 9 (Mmp9) in the gingiva; support and alveolar bone loss; connective tissue attachment; and the quantity of gingival collagen were evaluated. Results: Exenatide and sitagliptin treatments have led to a lower percentage of weight gain but did not influence glycemia. Sitagliptin reduced the serum concentration of DPP‐4. Interestingly, although the gene expression profile has revealed a downregulation of Mmp9, Nos2, and Il1b in both EG and SG compared to LG, a significant protective effect was not observed on alveolar bone and collagen tissue in this model. Conclusion: Regardless of the reduction of the expression of Il1b, Nos2, and Mmp9, the drugs were not effective in the stabilization or reduction of alveolar bone loss and collagen degradation in rats.  相似文献   
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95.
SCN5A encodes the α subunit of the major cardiac sodium channel NaV1.5. Mutations in SCN5A are associated with conduction disease and ventricular fibrillation (VF); however, the mechanisms that link loss of sodium channel function to arrhythmic instability remain unresolved. Here, we generated a large-animal model of a human cardiac sodium channelopathy in pigs, which have cardiac structure and function similar to humans, to better define the arrhythmic substrate. We introduced a nonsense mutation originally identified in a child with Brugada syndrome into the orthologous position (E558X) in the pig SCN5A gene. SCN5AE558X/+ pigs exhibited conduction abnormalities in the absence of cardiac structural defects. Sudden cardiac death was not observed in young pigs; however, Langendorff-perfused SCN5AE558X/+ hearts had an increased propensity for pacing-induced or spontaneous VF initiated by short-coupled ventricular premature beats. Optical mapping during VF showed that activity often began as an organized focal source or broad wavefront on the right ventricular (RV) free wall. Together, the results from this study demonstrate that the SCN5AE558X/+ pig model accurately phenocopies many aspects of human cardiac sodium channelopathy, including conduction slowing and increased susceptibility to ventricular arrhythmias.  相似文献   
96.
97.
The growing use of dermal fillers, specifically the use of hyaluronic acid, can be explained by their effectiveness and versatility as well as their favorable safety profiles. Nevertheless, early and late complications with varying levels of severity may occur. The incidence of complications is low and the majority of adverse events are mild (edema, erythema, and local ecchymosis) and of limited duration. However, more severe events, such as ischemia and necrosis, may occur. The symptoms of ischemia can occur immediately after the injection or several hours after the procedure. Here, the authors report three cases of necrosis after hyaluronic acid injection with the first symptoms presenting only several hours after the procedure. The patients were treated immediately after the diagnosis. The aim of this review is to communicate the possibility of the delayed-type presentation of necrosis, present the signs and symptoms that lead to early diagnosis, and review the treatment possibilities of this severe complication.Dermal fillers have been injected with increasing frequency over the past three decades for soft-tissue augmentation by volume expansion in the management of the aging face. In 2012, there were about two million procedures using dermal fillers, according to the American Society of Plastic Surgeons, five percent more than in 2011 and 205 percent more than in 2000, second only to botulinum toxin type A. These minimally invasive and nonsurgical cosmetic procedures were the two most commonly performed in this range of time studied.1,2The growing use of dermal fillers, specifically the use of hyaluronic acid (HA), can be explained by their effectiveness and versatility as well as their favorable safety profiles. Nevertheless, early and late complications with varying levels of severity may occur. The incidence of complications is low and the majority of adverse events are mild (edema, erythema, and local ecchymosis) and of limited duration. However, more severe events, such as ischemia and necrosis, may occur.Injection necrosis is a rare, but important, complication associated with dermal fillers. Necrosis can be attributed to one of two factors—an interruption of vascular supply due to compression or frank obstruction of vessels by direct injection of the material into a vessel itself. The glabella is the injection site commonly believed to be at greater risk for necrosis, but it can also occur at the nasolabial fold.3 Risk factors for intravascular injection include site of application (deep injection of filler products at or near the site of named vessels), volume applied (larger amounts of product can cause a proportionally greater degree of arterial obstruction), and previous scarring (deep tissue scars may stabilize and fix arteries in place, making them easier to penetrate with small sharp needles).4The initial presentation of vascular events may include pain and discomfort disproportionate to what is typically experienced following filler treatments and clinical findings, including blanching, livedo pattern, or violaceous discoloration.4 Although many cases report this immediate post-injection presentation as the typical background seen in a necrosis event, there are few reports with the first symptom presenting only hours after augmentation. See Figures 1 through through3,3, where the authors present three cases of vascular compromise after soft-tissue augmentation with delayed-type presentation. Open in a separate windowOpen in a separate windowFigures 2Aand 2B.Case 2: Necrosis and secondary infection 48 hours after the HA injection (a). Discrete scars in the affected area after treatment (b). Open in a separate windowOpen in a separate windowFigures 1Aand 1B.Case 1: Edema, erythema, and progressive violaceous reticulated patch, livedoid area were observed on the left cheek 36 hours after the injection (a). Complete healing five days after hyaluronidase application and nine days after the HA injection (b). Open in a separate windowOpen in a separate windowFigures 3Aand 3B.Case 3: Necrosis and secondary infection 48 hours after the HA injection (a). Erythema, hipercromia, and discreet scars in the affected area after treatment (b).  相似文献   
98.

Aims

To determine the cross-sectional threshold at which hemoglobin A1c (HbA1c) is associated with polyneuropathy in healthy controls, and the values associated with the most pronounced decline in nerve function in patients with diabetes.

Methods

We used data from a cross-sectional cohort study of healthy controls and type 2 diabetes patients assessed between November 2010 and May 2013. Healthy controls and patients with diabetes were compared at different HbA1c ranges: <5.5%, 5.5–5.9%, and 6–6.4% for controls, and 6.5–7.4% and >7.5% for patients with diabetes.

Results

The total cohort included 53 controls and 164 patients with diabetes. Subclinical small nerve fiber impairments were observed in controls at HbA1c levels of 5.5–6%, compared with HbA1c <5.5%, for example: lower Laser Doppler flare imaging area of 2.8?±?1.4 versus 3.9?±?2?mm2. The most prominent decline in both small and large nerve fiber function was seen with less impaired glycemic control and shorter duration of diabetes, i.e. at HbA1c levels of 6.5–7.4%, compared with >7.5%.

Conclusions

These findings underscore the importance of early treatment at the prediabetes and early diabetes stages to prevent nerve fiber decline that is likely irreversible.  相似文献   
99.

Background

Social determinants differ between countries, which is not always considered when adapting health policies and interventions to face inequalities in noncommunicable diseases and their risk factors.

Objectives

The study sought to analyze educational inequalities in controlled blood pressure (CBP), obesity, and smoking in study populations from Chile and the United States in 2 periods, both countries with large social inequalities.

Methods

The study used data from the first and fifth waves of the MESA (Multiethnic Study of Atherosclerosis) cohort, and the 2003 and 2009 to 2010 Chilean National Health Survey (CNHS) survey outcome measures. The study compared cardiovascular risk factors prevalence as well as relative index of inequality (RII) and slope index of inequality (SII) between the 2 samples.

Results

In the CNHS 67.9% and 52.6% of participants had below primary education in 2003 and 2009 to 2010, respectively, compared with 12.3% and 8.1% in the first and fifth waves of the MESA study, respectively. Smoking prevalence was higher and increased in the CNHS compared with the MESA study, concentrated in better-educated women in both years (RII: 0.34; 95% confidence interval [CI]: 0.17 to 0.68; and RII: 0.55; 95% CI: 0.34 to 0.89, respectively). In contrast, smoking decreased over time in the MESA study in all socioeconomic strata, although relative inequalities increased in both sexes (for women, RII: 2.32; 95% CI 1.36 to 3.97; for men, RII: 3.34; 95% CI 2.04 to 5.47). CBP prevalence in both periods was higher in the first and fifth waves of the MESA study (69.7% and 80.2%) compared with the 2003 and 2009 to 2010 CNHS samples (34.2% and 52.3%), but only for the MESA study RII, favoring the better educated, was it significant in both periods and sexes. Obesity inequalities for Chilean women decreased slightly between 2003 and 2009 as prevalence grew in the most educated (RII: 2.21 to 1.68; SII: 0.29 to 0.22, respectively); conversely, they increased for both sexes in the MESA study.

Conclusions

The study findings confirm that patterns and trends in prevalence, and absolute and relative inequalities vary by country, suggesting that context and cultural issues matters.  相似文献   
100.
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