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81.

Background

Treatment of esophageal adenocarcinoma often involves surgical resection. Newer technologies in interventional endoscopy have led to a substantial paradigm shift in the management of early-stage neoplasia in Barrett’s esophagus comprising high-grade dysplasia (HGD), intramucosal carcinoma, and, in some cases, submucosal carcinoma. However, there has been no consensus regarding the indications for esophageal preservation in these cases. In this work, consensus guidelines were established for the management of early-stage esophageal neoplasia considering clinically relevant aspects (age, comorbidities, and social environment) in each scenario.

Methods

Seventeen experts were invited to participate based on their background and clinical expertise at high-volume centers. A questionnaire was created that included four clinical scenarios covering a wide range of situations within HGD and/or early esophageal neoplasia, particularly where controversies are likely to exist. Each of the clinical scenarios was open to discussion subdivided by patient age (20, 50, and 80 s). For each clinical scenario an expert was chosen to defend that position. Each defense triggered a subsequent discussion during a consensus meeting. Conclusions of that discussion together with an accompanying literature analysis allowed experts to confirm or change their original choices and served as the basis for the recommendations stated in this article.

Results

There was 100 % consensus supporting esophageal preservation in patients with HGD, independent of patient age or Barrett’s length. In patients with T1a adenocarcinoma, consensus for preservation was not reached (65 %) for young and middle-aged individuals but was supported for elderly patients (100 %). For T1b adenocarcinoma, consensus was reached for surgical resection (90 %), leaving organ preservation for patients with very low risk of nodal invasion or poor surgical candidates.

Conclusion

Advances in endoscopic imaging and therapy allow for organ preservation in most settings of early-stage neoplasia of the esophagus, provided that the patient understands the implications of this decision.  相似文献   
82.
In this paper, we study constrained Markov control processes on Borel spaces with possibly unbounded one‐stage cost, under a discounted optimality criterion with random discount factor and restrictions of the same kind. We prove that the corresponding optimal control problem is equivalent to an infinite‐dimensional linear programming problem. In addition, considering the dual program, we show that there is no duality gap, and moreover, the strong duality condition holds. Hence, both programs are solvable, and their optimal values coincide. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
83.
Several recent studies suggest that obesity may be a risk factor for fracture. The aim of this study was to investigate the association between body mass index (BMI) and future fracture risk at different skeletal sites. In prospective cohorts from more than 25 countries, baseline data on BMI were available in 398,610 women with an average age of 63 (range, 20–105) years and follow up of 2.2 million person‐years during which 30,280 osteoporotic fractures (6457 hip fractures) occurred. Femoral neck BMD was measured in 108,267 of these women. Obesity (BMI ≥ 30 kg/m2) was present in 22%. A majority of osteoporotic fractures (81%) and hip fractures (87%) arose in non‐obese women. Compared to a BMI of 25 kg/m2, the hazard ratio (HR) for osteoporotic fracture at a BMI of 35 kg/m2 was 0.87 (95% confidence interval [CI], 0.85–0.90). When adjusted for bone mineral density (BMD), however, the same comparison showed that the HR for osteoporotic fracture was increased (HR, 1.16; 95% CI, 1.09–1.23). Low BMI is a risk factor for hip and all osteoporotic fracture, but is a protective factor for lower leg fracture, whereas high BMI is a risk factor for upper arm (humerus and elbow) fracture. When adjusted for BMD, low BMI remained a risk factor for hip fracture but was protective for osteoporotic fracture, tibia and fibula fracture, distal forearm fracture, and upper arm fracture. When adjusted for BMD, high BMI remained a risk factor for upper arm fracture but was also a risk factor for all osteoporotic fractures. The association between BMI and fracture risk is complex, differs across skeletal sites, and is modified by the interaction between BMI and BMD. At a population level, high BMI remains a protective factor for most sites of fragility fracture. The contribution of increasing population rates of obesity to apparent decreases in fracture rates should be explored. © 2014 American Society for Bone and Mineral Research.  相似文献   
84.
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87.

Introduction

One of the pathways involved in pulmonary arterial hypertension (PAH) is the nitric oxide (NO) pathway. A polymorphism in the inducible NO synthase (NOS2) gene has been described, consisting of the CCTTT pentanucleotide repeat, which causes a reduction in NO production. The aim of this study was to determine if this polymorphism increases susceptibility to developing PAH.

Methods

Sixty four patients with a diagnosis of PAH groups i and iv and 50 healthy controls were compared. DNA genotyping of the samples for this polymorphism was performed using PCR. The distribution between both groups was compared and correlated with clinical and haemodynamic parameters and therapeutic response.

Results

A significantly different distribution was observed in the number of repeats between patients and controls (P < .0001). When the samples were categorised by short forms (both alleles with less than 12 repeats) and long forms (≥ 12 repeats), it was observed that the former had an almost 4-fold risk of developing PAH (odds ratio: 3.83; 95% CI: 1.19-12.32, P = .024). There were no differences between the most common types of PAH, either in therapeutic response or survival. There was no correlation between haemodynamic parameters and the number of repeats in the patients, and only a weak correlation with systolic PAH.

Conclusions

There are significant differences in the distribution of the NOS2 promotor CCTTT polymorphism between patients with PAH and the healthy population. A minor CCTTT pentanucleotide repeat in the NOS2 gene may increase the risk of developing PAH.  相似文献   
88.
89.
Although esophagogastroduodenoscopy (EGD) is the most commonly used procedure in the gastrointestinal (GI) tract, the method of esophageal, gastric and duodenal mucosa photodocumentation varies considerably worldwide. One probable explanation is that for generations, EGD has primarily been taught by GI faculty and instructors based on their perceptions and experience, which has resulted in EGD being a non-standardized procedure. Currently, the procedure is facing a challenging scenario as endoscopy societies are implementing procedure-associated quality indicators aiming for best practice among practitioners and evidence-based care for patients. Contrary to colonoscopy where cecum landmarks photodocumentation is considered proof of completeness, there are currently no reliable performance measures to gauge the completeness of an upper endoscopy nor guidance for complete photodocumentation. This World Endoscopy Organization (WEO) position statement aims to provide practical guidance to practitioners to carry out complete EGD photodocumentation. Hence, an international group of experts from the WEO Upper GI Cancer Committee formulated the following document using the body of evidence established through literature reviews, expert opinions, and other scientific sources. The group acknowledged that although the procedure should be feasible in any facility, what is needed to achieve a global shift on the concept of completeness is a common written statement of agreement on its potential impact and added value. This best practice statement offers endoscopists principles and practical guidance in order to carry out complete photodocumentation from the hypopharynx to the second duodenal portion.  相似文献   
90.

Background

Serial changes in dietary intake, including specific food groups and nutrients during the first year following Roux-en-Y gastric bypass (RYGB) are of interest due to surgically induced alterations in meal size, food intolerances present after surgery, and potential nutrient deficiencies. To help improve the nutritional health of surgical patients, this study’s purpose was to examine changes in macro- and micronutrients, food groups, and selected foods during 12 months of follow-up in post-RYGB individuals.

Methods

RYGB patients (n?=?17) completed 4-day food records at baseline (prior to surgery) and then at 3 weeks, 3 months, 6 months, and 12 months after surgery. Mean daily intake was determined at each time for energy intake, macro- and micronutrients, food groups, and selected foods in targeted food groups.

Results

A dramatic decrease in mean (±SEM) daily energy intake occurred—2,150?±?165 kcal at baseline vs. 649?±?40 kcal at 3 weeks; energy intake continually increased to a high of 1,307?±?129 kcal by 12 months. More than 50 % of patients had low intake of vitamins D, E, C, folate, and calcium, magnesium, and potassium at 12 months. Servings from vegetables, grains, fats, and sweetened beverages were lower, whereas, meats, dairy, fruits, and sweets showed only small, transient changes following surgery.

Conclusions

The reduction in energy intake following RYGB is from selected food groups and not solely a reduction in portion sizes across the diet. The lower intake of micronutrients indicates potential risk for deficiencies unless supplements are used. These findings can help in the clinical management of surgical patients to improve nutritional health.  相似文献   
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