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81.
Because urine ion excretion varies throughout the day, clinicians monitor 24 h urine samples to measure ion excretion and supersaturation in kidney stone patients. However, these results are averages and may not reflect maximal supersaturation which drives stone formation. We measured ion excretion and saturation in genetic hypercalciuric stone-forming rats on both a normal or low calcium diet over 0-3, 3-6 and 6-24 h using two feeding protocols, where the daily food allotment was fed either as a bolus or divided into three portions. With a normal calcium diet, urine calcium, oxalate, volume, and calcium oxalate supersaturation were significantly greater on the bolus compared to the divided feeds in the prandial and postprandial periods. Bolus eaters also excreted more calcium and oxalate and had increased volume over 24 h. Maximal calcium oxalate supersaturation was greater during the initial time periods than during the entire 24 h, regardless of the feeding schedule. With the low calcium diet, the effect of bolus feeding was reduced. Thus, urine ion excretion and supersaturation vary with the type of feeding. If these results are confirmed in man, it suggests that eating as a bolus may result in greater prandial and postprandial calcium oxalate supersaturation. This may increase growth on Randall's plaques and promote stone disease.  相似文献   
82.
Enhanced angiogenesis and perineural invasion are markers of poor prognosis in patients with pancreatic cancer. Systemic therapies for pancreatic cancer have been largely ineffective, and thus improved, targeted therapies are needed. Single nucleotide polymorphisms (SNP) are DNA sequence variations that result in vast diversity of disease susceptibility and response to disease. CXCR2 is an important mediator of CXC chemokine-induced angiogenesis and is upregulated in pancreatic cancer. In a preclinical corneal micropocket assay, treatment of pancreatic cancer cell lines that express CXCR2 with anti-CXCR2 antibody inhibited angiogenesis. To date, there have not been any CXCR2 SNP associated with pancreatic cancer, but CXCR2 SNP has been postulated to be associated with angiogenesis in systemic sclerosis. The receptor tyrosine kinase encoded by the RET gene and its ligand glial derived neurotrophic factor (GDNF) are upregulated in pancreatic cancer. In vitro treatment of pancreatic cancer cell lines that express RET with anti-RET antibody or RET siRNA-inhibited GDNF-induced invasiveness. G691S RET SNP has been previously shown to be associated with enhanced pancreatic cancer invasiveness. We suggest that molecular profiling of each patient’s tumor for G691S RET SNP, potentially CXCR2 SNP, and also other yet-to-be identified SNP associated with pancreatic cancer will allow for both improved understanding of individual prognosis and allow for utilization of more personalized, targeted adjuvant therapies. This work was presented at the Molecular Surgeon Symposium on Personalized Genomic Medicine and Surgery at the Baylor College of Medicine, Houston, TX, USA, April 12, 2008. The symposium was supported by a grant from the National Institutes of Health (R13 CA132572 to Changyi Chen).  相似文献   
83.

Background

Compared to the widely adopted 2–4 months of pre-operative therapy for patients with borderline resectable (BR) or locally advanced (LA) pancreatic ductal adenocarcinoma (PDAC), our institution tends to administer a longer duration before considering surgical resection. Using this unique approach, the aim of this study was to determine pre-operative variables associated with survival.

Methods

Records from patients with BR/LA PDAC who underwent attempt at surgical resection from 1992–2014 were reviewed.

Results

After a median duration of 6 months of pre-operative treatment, 109 patients with BR/LA PDAC (BR 63, LA 46) were explored; 93 (85.3 %) underwent pancreatectomy. Those who received at least 6 months of pre-operative treatment had longer median overall survival (OS) than those who received less (52.8 vs. 32.1 months, P?=?0.044). On multivariate analysis, pre-operative treatment duration was the strongest predictor of survival (hazard ratio (HR) 4.79, P?=?0.043). However, OS was similar in those whose CA19-9 normalized regardless of whether they received more or less than 6 months of chemotherapy (71.4 vs. 101.8 months, P?=?0.930).

Conclusions

Pre-operative CA19-9 decline can guide treatment duration in patients with BR/LA PDAC. We endorse 6 months of therapy except in those patients whose values normalize, where surgery can be considered after a shorter course.
  相似文献   
84.

Background

Adolescent obesity is a significant global health challenge and severely obese adolescents commonly experience serious medical and psychosocial challenges. Consequently, severe adolescent obesity is increasingly being treated surgically. The limited available research examining the effectiveness of adolescent bariatric surgery focuses primarily on bio-medical outcomes. There is a need for a more comprehensive understanding of the behavioural, emotional and social factors which affect adolescents’ and parents’ experience of weight loss surgery.

Methods

Patient and parents’ perspectives of adolescent LAGB were examined using a qualitative research methodology. Individual, semi-structured interviews were conducted with eight adolescent patients and five parents. Thematic analysis was used to identify key themes in the qualitative data.

Results

Patients and parents generally considered adolescent laparoscopic adjustable gastric banding (LAGB) to be a life-changing experience, resulting in physical and mental health benefits. Factors considered to facilitate weight loss following surgery included parental support and adherence to treatment guidelines. Many adolescents reported experiencing surgical weight loss stigma and challenging interpersonal outcomes after weight loss for which they felt unprepared.

Conclusions

Patients and parents perceived LAGB positively. There are opportunities to improve both the experience and outcomes of adolescent LAGB through parental education and enhancements to surgical aftercare programmes.
  相似文献   
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Laparoscopic Heller myotomy (LHM) has become the standard treatment option for achalasia. The incidence of esophageal perforation reported is about 5%–10%. Robotically assisted Heller myotomy (RAHM) is emerging as a safe alternative to LHM. Data comparing the two approaches are scant. The aim of this study was to compare RAHM with LHM in terms of efficacy and safety for treatment of achalasia. A total of 121 patients underwent surgical treatment of achalasia at three institutions. A retrospective review of prospectively collected perioperative data was performed. Patients were divided into two groups: group A (RAHM), 59 patients, and group B (LHM), 62 patients. All the operations were completed using minimally invasive techniques. There were 63 women and 58 men, with a mean age of 45 ±19 years (14–82 years). Fifty-one percent of patients in group A and 95% of patients in group B reported weight loss. Duration of symptoms was equal for both groups. Dysphagia was the main complaint in both groups (P = NS). There was no difference in preoperative endoscopic treatment in both groups (44% versus 27%, P = NS). Operative time was significantly shorter for LHM in the first half of the experience (141 ± 49 versus 122 ± 44 minutes, P < .05). However, in the last 30 cases there was no difference in operative time between the groups (P = NS). Intraoperative complications (esophageal perforation) were more frequent in group B (16% versus 0%). The incidence of postoperative heartburn did not differ by group. There were no deaths. At 18 and 22 months, 92% and 90% of patients had relief of their dysphagia. This study suggests that RAHM is safer than LHM, because it decreases the incidence of esophageal perforation to 0%, even in patients who had previous treatment. At short-term follow-up, relief of dysphagia was equally achieved in both groups. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation). This study was supported in part by a grant provided by Intuitive Surgical, Inc. and Ethicon Endo-Surgery, Inc.  相似文献   
87.
BACKGROUND: Insulin-like growth factor-I (IGF-I) is a potent mitogen for both normal and malignant prostate epithelial cells. The majority of circulating IGF-I is bound in a complex with IGF binding protein-3 (IGFBP-3), which in turn limits IGF-I bioavailability. Multiple studies suggest that higher IGF-I and/or lower IGFBP-3 serum levels are positively associated with prostate cancer risk. Several polymorphisms within the IGF-I and IGFBP-3 coding regions have been associated with increased serum protein levels. METHODS: To ascertain the potential relationship between serum levels and polymorphism, and prostate cancer risk, we investigated the role of two polymorphisms the IGF-I cytosine-adenosine (CA)-repeat and the IGFBP-3 Ala32Gly, and prostate cancer in a population-based, case-control, study of middle-aged men. RESULTS: We found no significant association between the IGFBP-3 Ala32Gly polymorphism and prostate cancer risk, even though the presence of at least one Gly allele did correlate with increased serum levels of IGFBP-3. For IGF-I, more controls (42%) than cases (38%) were homozygous for 19-CA-repeats (odds ratio, OR = 0.85; 95% confidence interval (CI) = 0.66-1.09). After stratifying by disease characteristics, 19-CA-repeat homozygous men displayed a decreased risk of low-grade disease (OR = 0.50; 95% CI = 0.27-0.93), but no associations were observed with more aggressive features of disease. Additionally, there was no correlation between mean serum IGF-I protein levels and IGF-I genotype in controls. CONCLUSIONS: Further evaluation of the IGF-I CA-repeat polymorphism and prostate cancer is necessary to determine if the modest risk reduction associated with the 19-CA-repeat homozygous state is observed in other study populations.  相似文献   
88.
Abstract

Objective: To integrate gene expression profiling into the management of high-risk cutaneous squamous cell carcinoma (cSCC) within the National Comprehensive Cancer Network (NCCN) guidelines to improve risk-aligned management recommendations.

Methods: A cohort of 300 NCCN-defined high-risk cSCC patients, along with the American Joint Committee on Cancer (AJCC) T stage, Brigham and Women’s Hospital (BWH) T stage, and known patient outcomes were analyzed. Risk classifications using a validated 40-gene expression profile (40-GEP) test and T stage were applied to NCCN patient management guidelines. Risk-directed patient management recommendations within the NCCN guidelines framework were aligned based on risk for metastasis.

Results: Of the 300 NCCN high-risk cSCC patients, 159 (53.0%) were 40-GEP Class 1 and AJCC T1-T2, and 173 (57.7%) were Class 1 and BWH T1-2a, indicating low risk for metastasis and, thereby, suggesting low management intensity. The 40-GEP integration suggested high intensity management for only 24 (8.0%) patients (all Class 2B), and moderate intensity management for the remainder of the cohort.

Conclusions: The 40-GEP test can be integrated within existing NCCN guideline recommendations for managing cSCC patients to help refine risk-directed management decisions. Integration of the 40-GEP test would allow >50% of this NCCN-defined high-risk cohort to be managed with the lowest intensity recommendations within the broad NCCN guidelines. High intensity management was deemed risk-appropriate for a small subpopulation (8.0%). This study demonstrates that the 40-GEP test, in combination with T stage, has clinical utility to impact patient management decisions in NCCN high-risk cSCC for improving risk-aligned management within the NCCN guidelines framework.  相似文献   
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