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991.
Aim: Near‐infrared spectroscopy (NIRS) allows estimation of the percentage of body fat (%BF) regardless of the patient's posture; thus, it is useful for assessment of elderly patients with severe decline of basic activity who cannot hold a standing position. However, the accuracy by which the near‐infrared light emitted from NIRS reflects subcutaneous tissue is unknown. The aim of this study was to assess how correctly NIRS reflects the subcutaneous fat and muscle thickness derived from ultrasonography in community‐dwelling elderly. Methods: A total of 93 community‐dwelling older adults aged 65 years and older were enrolled in this study (mean 75.8 years, 6.7 SD). Participants were assessed according to optical density (OD) measurements by NIRS, subcutaneous fat and muscle thickness by ultrasonography, and muscle strength. Pearson's correlation coefficients were calculated for each sex. Stepwise multiple regression analysis was used to identify factors that contributed to OD for each sex. Results: OD measured at the forearm and thigh were significantly correlated with subcutaneous fat thickness. In stepwise multiple regression analyses, subcutaneous fat thickness was found to be a significant determinant of OD in men (forearm β = −0.37, P = 0.01; thigh β = −0.63, P < 0.001) and women (forearm β = −0.50, P < 0.001; thigh: β = −0.52, P < 0.001). Conclusions: These results suggest that NIRS can appropriately estimate fat‐free mass. By adding other variables to OD as the predictive variable, skeletal muscle mass might be estimated in the elderly population. Geriatr Gerontol Int 2013; 13: 351–357 .  相似文献   
992.

Background

Few studies have focused on right atrial (RA) structure and function in pulmonary hypertension (PH). We sought to evaluate RA volume and phasic function using cardiac magnetic resonance (CMR), and to examine their clinical relevance in PH.

Methods

We prospectively studied 50 PH patients and 21 control subjects. RA volume and indices of phasic function (reservoir volume, ejection fraction [EF], and conduit volume) were evaluated by CMR.

Results

Maximum RA volume index was significantly higher in PH patients (56 [44–70] ml/m2) than in controls (40 [30–48] ml/m2) (p < 0.001). Reservoir volume index was significantly lower in PH than in controls (p < 0.001), but conduit volume index was higher in PH than in controls (p = 0.008). RA EF was similar when comparing the two groups (p = 0.925). Interestingly, RA EF was increased in PH patients with WHO functional class III patients as compared with controls (p < 0.001) but was reduced in advanced PH patients with WHO functional class IV (p < 0.01). Maximum RA volume and RA EF significantly correlated with pulmonary hemodynamic indices, atrial and brain natriuretic hormone levels, and CMR-derived right ventricular indices. By contrast, RA reservoir volume correlated with cardiac index and 6-minute walk distance.

Conclusions

PH is associated with increased size, decreased reservoir function, and increased conduit function of the right atrium. RA systolic function indicated by RA EF increases in patients with mild to moderate PH but decreases in patients with advanced PH. Varying associations between RA indices and conventional PH indices suggest their unique role in the management of PH.  相似文献   
993.
Clinical Rheumatology - Sympathetic storms (SyS) are characterized by hyperactivity of autonomic functions, resulting in episodes of hyperthermia, hypertension, tachycardia, and hyperhidrosis. We...  相似文献   
994.
In order to clarify the mechanism of mesangial cell dysfunction in diabetes, we examined the activities of protein kinase C (PKC) and mitogen-activated protein kinase (MAPK), important kinases in various cellular functions, and also evaluated the isoenzymes of PKC in mesangial cells cultured under high glucose conditions. Exposure of cells to high concentrations (27.8 mM) of glucose for 5 days resulted in a significant elevation of PKC activities in the membrane fraction. MAPK was also activated in cells cultured under high glucose conditions. Of the PKC isoenzymes, the levels of PKC and ζ were significantly increased in the membrane fraction after 5 days of exposure to high concentrations of glucose. These results indicate that the translocation of PKC and ζ and the activation of MAPK under high glucose conditions might be underlying mechanisms of the functional disturbance of mesangial cells in diabetes.  相似文献   
995.
Tyrosine kinase 2 (TYK2) is a type I interferon (IFN) signaling pathway gene and was previously reported to be a risk factor for systemic lupus erythematosus (SLE) in Caucasian populations. In order to test for its genetic association with SLE in a Japanese population, TYK2 single nucleotide polymorphisms (SNPs), rs2304256, rs12720270 and rs280519, were genotyped. A case–control association study was performed in a total of 411 Japanese SLE patients and 467 healthy controls. Linkage disequilibrium (LD) among TYK2 SNPs was examined. According to the data from 94 healthy controls, non-synonymous rs2304256 resulting in Val → Phe substitution was revealed to be in a LD with rs12720270 and rs280519. Therefore, we further genotyped rs2304256 as a tag SNP in the full sample sets. As a result, no differences in genotype distribution and allelic frequencies of rs2304256 were found between SLE patients and healthy controls. In conclusion, TYK2 is not a genetic risk factor for SLE in a Japanese population. Our result suggests that there is an ethnic difference in the susceptibility genes for SLE.  相似文献   
996.
Background Heat shock protein 70-2 (HSP70-2) has a cytoprotective role in various conditions and also protects the gastric mucosa. Recently, polymorphism of HSP70-2 at position 1267 was suggested to be associated with carcinogenesis. We investigated the association of this polymorphism with the risk of gastric cancer in the present study. Methods We examined 223 patients (159 men and 64 women, mean age 64.8 years) with gastric cancer who underwent gastrointestinal endoscopy at our department. The controls were 200 age-matched patients (140 men and 60 women) without gastric cancer diagnosed by gastrointestinal endoscopy. Genotyping was done by PCR-based restriction fragment length polymorphism analysis, and the PCR products were digested with PstI. The two allelic forms, corresponding to the presence or absence of the PstI site, were designated as the P1 allele and P2 allele, respectively. Logistic regression analysis was performed to calculate an odds ratios (ORs) for differences of HSP70-2 polymorphism between the two groups. Results Among the 223 patients with gastric cancer, 46 (20.6%) had P1/P1, 177 (79.4%) were P1 carriers, and 6 (2.7%) were P2/P2. In the control group, 33 (16.5%) patients had P1/P1 polymorphism, 167 (83.5%) were P1 carriers, and 12 (6.0%) were P2/P2. The OR for gastric cancer of subjects with P2/P2 polymorphism relative to P1 carriers was 0.43 (95% CI = 0.16–1.17) (P = 0.097). Among females, the OR for gastric cancer of subjects with P2/P2 polymorphism relative to P1 carriers was 0.10 (95% CI = 0.012–0.838) (P = 0.014). This polymorphism was also associated with a lower risk of middle third cancer (OR = 0.13; 95% CI = 0.02–1.00). Conclusions P2/P2 polymorphism of HSP70-2 at position 1267 was associated with a lower risk of gastric cancer in females.  相似文献   
997.

Purpose

To assess the mid-term results of MR-guided percutaneous cryoablation for small hepatocellular carcinoma (HCC).

Methods

Using an argon-based cryoablation system, MR-guided percutaneous cryoablation was performed. The number of tumors was three or fewer. The maximum diameter of tumors was less than 5 cm when solitary and no more than 3 cm when multiple. The Kaplan–Meier method was used to calculate the survival of patients.

Results

Among 15 patients, 16 tumors were treated. The maximum tumor diameter ranged from 1.2 to 4.5 cm, with a mean of 2.5 ± 0.8 cm (mean ± standard deviation). The volume of iceballs measured on MR-images was greater than that of the tumors in all cases. The follow-up period ranged from 10 to 52 months, with a mean of 36.6 ± 12.1 months. One-year and 3-year overall survival were 93.8 and 79.3%, respectively. The complete ablation rate was 80.8% at 3 years. Immediate complications were pneumothorax, hemothorax, and pleural effusion. An ablation zone was not absorbed and content exuded from a scar of the probe tract 4 months after cryoablation in one patient.

Conclusion

MR-guided percutaneous cryoablation appears to be a feasible modality and potentially good option for the treatment of small HCC.
  相似文献   
998.
We reviewed the clinicopathological characteristics of 14 patients who underwent resection of basaloid squamous carcinoma (BSC) of the esophagus. The mean age was 65.3 years, and all patients were male. Seven patients had superficial BSCs and 7 had advanced BSCs. BSCs were associated with high rates of lymph node metastases and venous invasion. With regard to immunohistochemistry, the rate of cyclin D1 expression was higher (13/14), and the preservation rate of E-cadherin expression was lower (4/14), than that seen in ordinary esophageal squamous cell carcinoma. Squamous cell carcinoma components were most often found at sites of lymph node metastases, whereas basaloid components predominated at sites of hematogenous metastases in 4 patients, including lung, brain, and liver. Seven of the 9 patients with stage I or II disease are alive without recurrence. All patients with stage III or IV tumors developed recurrent disease. Primary tumors responded well in 3 patients who received preoperative chemotherapy (5-fluorouracil plus cisplatin) and/or radiotherapy, but further studies are needed to clarify the role of chemoradiotherapy. We believe that control of the hematogenous spread of basaloid components may lead to improved outcomes in patients with esophageal BSC.  相似文献   
999.
In order to better understand the endocrine aberrations related to abnormal metamorphic pigmentation that appear in flounder larvae reared in tanks, this study examined the effects of continuous 24-h illumination (LL) through larval development on the expression of tyrosine hydroxylase-1 (th1), proopiomelanocortin (pomc), α-melanophore-stimulating hormone (α-MSH) and melanin concentrating hormone (MCH), which are known to participate in the control of background adaptation of body color. We observed two conspicuous deviations in the endocrine system under LL when compared with natural light conditions (LD). First, LL severely suppressed th1 expression in the dopaminergic neurons in the anterior diencephalon, including the suprachiasmatic nucleus (SCN). Second, pomc and α-MSH expression in the pars intermedia melanotrophs was enhanced by LL. Skin color was paler under LL than LD before metamorphic pigmentation, and abnormal metamorphic pigmentation occurred at a higher ratio in LL. We therefore hypothesize that continuous LL inhibited dopamine synthesis in the SCN, which resulted in up-regulation of pomc mRNA expression in the melanotrophs. In spite of the up-regulation of pomc in the melanotrophs, larval skin was adjusted to be pale by MCH which was not affected by LL. Accumulation of α-MSH in the melanotrophs is caused by uncoupling of α-MSH synthesis and secretion due to inhibitory role of MCH on α-MSH secretion, which results in abnormal metamorphic pigmentation by affecting differentiation of adult-type melanophores. Our data demonstrate that continuous illumination at the post-embryonic stage has negative effects on the neuroendocrine system and pituitary in flounder.  相似文献   
1000.
Recently, the progress of endoscopy has made it possible to evaluate bile duct mucosa by peroral cholangioscopy. Herein, we report a case of immunoglobulin G4-related sclerosing cholangitis accompanying autoimmune pancreatitis in a patient who improved with treatment by steroid therapy and endoscopic biliary stenting, and observed the bile duct mucosa by peroral cholangioscopy before and after treatment.  相似文献   
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