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101.
Melasma is triggered by various factors including ultraviolet radiation and estrogen; however, its pathogenesis is unclear. To investigate the inflammatory features of melasma lesions as triggers for this disorder, 197 women with melasma who attended Asan Medical Center and Kangskin Clinic, Seoul, from June 2011 to October 2011 completed a questionnaire concerning triggering or aggravating factors. These cases were divided into “non‐inflammatory” and “inflammatory” groups. Skin biopsies and immunostaining for CD68, CD117, and leukocyte common antigen (LCA) were performed in the lesional and peri‐lesional skin of ten cases in the non‐inflammatory group and nine cases in the inflammatory group. Among the 197 subjects (mean age, 41.5 years; mean age of melasma onset, 33.8 years), 50 patients (25.4%) were categorized into the inflammatory group. This group comprised cases that had inflammatory symptoms and events that triggered the melasma lesions. The lesional dermis contained more CD68+ melanophages, CD117+ mast cells, and LCA+ leukocytes in the inflammatory group than in the non‐inflammatory group. Inflammatory clinical features and an increased number of inflammatory cells in the lesion may be involved in the development of melasma in Asian skin.  相似文献   
102.
背景: 不同地区骨峰值和标准差不同,对骨质疏松诊断率有较大影响。探讨建立一完整数据库为中国人骨质疏松诊断准确性提供依据。 目的:探讨青年人腰椎骨密度和标准差正常参考值影响骨质疏松症检出率的程度。 设计、时间及地点:调查分析,于1997-01/1999-12分别在北京、上海、广州、南京、嘉兴和成都市完成。 对象:采用前瞻性及回顾性方法对全国6个中心骨密度参考数据库中11 418人进行调查统计分析;男3 666人,女7 752人;年龄20岁~90岁;分别来自北京(2 385人)、广州(1 178人)、上海(1 404人)、南京(2 938人)、成都(1 425人)、嘉兴(2 088人),受试者来源于社区调查、健康体检和健康志愿者。 方法:用GE-Lunar公司的DXA仪测量骨密度,调查全国6个中心11 418人L2~L4腰椎后前位和髋部骨密度,建立了骨密度参考数据库。6个中心的仪器内部精度0.3%~0.7%,仪器间的精度1.1%。 主要观察指标:①6个中心不同年龄组腰椎骨密度分布。②青年人群骨密度及其标准差值对骨质疏松症检出率的影响。 结果:中国汉族女性以腰椎进行骨质疏松症诊断的青年人群的骨密度和标准差值,6个中心,最大差值分别为0.098 g/cm2和0.027 g/cm2。用6个中心及总体各自的青年人平均骨密度和标准差值为参考标准,对同一人群计算T-score和获得的骨质疏松症检出率不相同;发现青年人平均骨密度每变化0.01 g/cm2,则骨质疏松症检出率变化1.6%(呈正相关),其标准差值每变化 0.01 g/cm2,则骨质疏松症检出率变化4%(呈负相关)。 结论:青年人平均骨密度和标准差值不同引起骨质疏松症检出率也不相同。为了让不同中心的骨质疏松症检出率有可比性,建议同一个类型的骨密度仪,同一个种族,同一个地区用一个设计较完善大样本的参考数据库,以其青年人正常参考值计算T-score。  相似文献   
103.
104.
Noh Y  Kwon OK  Kim HJ  Kim JS 《Journal of neurology》2011,258(10):1775-1780
Rotational vertebral artery syndrome (RVAS) is characterized by recurrent attacks of paroxysmal vertigo, nystagmus, and ataxia induced by head rotation. We report on a patient who developed atypical RVAS due to compression of the vertebral artery (VA) terminating in the posterior inferior cerebellar artery (PICA). A 59-year-old man suffered from vertigo and nystagmus induced by leftward head rotation and oculography showed right beating horizontal-torsional and downbeat nystagmus. Cerebral angiography showed hypoplastic right VA terminating in PICA without connection to the basilar artery. The basilar artery received its flow from the left VA only and branched out both anterior inferior cerebellar arteries. Cerebral angiography revealed a complete occlusion of the right distal VA at the level of the C1–2 junction when the head was rotated to a leftward position. In contrast, the blood flow through the left vertebral and basilar arteries remained intact while turning the head to either side. The hemodynamic compromise observed in our patient with RVAS indicates that isolated vertigo and nystagmus may occur due to transient ischemia of the inferior cerebellum or lateral medulla.  相似文献   
105.

Objective

this study was to evaluate the impact of a quality improvement initiative in Malawi on reproductive health service quality and related outcomes.

Design

(1) post-only quasi-experimental design comparing observed service quality at intervention and comparison health facilities, and (2) a time-series analysis of service statistics.

Setting

sixteen of Malawi's 23 district hospitals, half of which had implemented the Performance and Quality Improvement (PQI) intervention for reproductive health at the time of the study.

Participants

a total of 98 reproductive health-care providers (mostly nurse–midwives) and 139 patients seeking family planning (FP), antenatal care (ANC), labour and delivery (L&;D), or postnatal care (PNC) services.

Intervention

health facility teams implemented a performance and quality improvement (PQI) intervention over a 3-year period. Following an external observational assessment of service quality at baseline, facility teams analysed performance gaps, designed and implemented interventions to address weaknesses, and conducted quarterly internal assessments to assess progress. Facilities qualified for national recognition by complying with at least 80% of reproductive health clinical standards during an external verification assessment.

Measurements

key measures include facility readiness to provide quality care, observed health-care provider adherence to clinical performance standards during service delivery, and trends in service utilisation.

Findings

intervention facilities were more likely than comparison facilities to have the needed infrastructure, equipment, supplies, and systems in place to offer reproductive health services. Observed quality of care was significantly higher at intervention than comparison facilities for PNC and FP. Compared with other providers, those at intervention facilities scored significantly higher on client assessment and diagnosis in three service areas, on clinical management and procedures in two service areas, and on counselling in one service area. Service statistics suggest that the PQI intervention increased the number of Caesarean sections, but showed no impact on other indicators of service utilisation and skilled care.

Conclusions

the PQI intervention showed a positive impact on the quality of reproductive health services. The effects of the intervention on service utilisation had likely not yet been fully realized, since none of the facilities had achieved national recognition before the evaluation. Staff turnover needs to be reduced to maximise the effectiveness of the intervention.

Implications for practice

the PQI intervention evaluated here offers an effective way to improve the quality of health services in low-resource settings and should continue to be scaled up in Malawi.  相似文献   
106.
Lymphangiomas in children: MR imaging   总被引:9,自引:0,他引:9  
Seventeen lymphangiomas in 15 patients were imaged with magnetic resonance (MR) to define the nature, extent, and anatomic relationships of these lesions. The MR and pathologic findings were then compared to determine the histologic basis for the signal-intensity characteristics of these lesions. The signal intensity of 13 lesions was similar to or slightly less than that of muscle on T1-weighted images and greater than that of fat on T2-weighted images. This appearance correlated with the presence of ectatic lymphatic channels containing clear fluid on histologic section. Four lymphangiomas had high signal intensity, approximately equal to that of fat, on T1-weighted images, reflecting the presence of clotted blood or small cystic spaces with a higher ratio of fat to fluid. Sixteen of 17 lesions had visible septations on MR images. The authors' experience suggests that most lymphangiomas have a characteristic appearance on MR images. The information obtained with MR imaging can help in providing a preoperative diagnosis, in planning surgical resection, and in defining recurrence.  相似文献   
107.

Background

The clinical usefulness of tumor markers as predictors of treatment outcome in patients with stomach cancer after radical gastrectomy has been poorly defined. The purpose of this study was to evaluate a comprehensive understanding of the impact of early postoperative tumor marker normalization on survival after gastrectomy.

Methods

Between January 2001 and December 2007, we enrolled 206 patients who had received radical gastrectomy as an initial treatment and had elevated carcinoembryonic antigen (CEA) (>5 ng/mL) or carbohydrate antigen (CA) 19-9 (>37 U/mL) levels. Early tumor marker response was defined as a normalization of preoperative CEA or CA19-9 values 1–2 months after gastrectomy.

Results

The mean patient age was 61 years (range 29–84 years), and 139 patients (67.5 %) were male. Early tumor marker response was identified in 150 of 206 (72.8 %) patients. Of the patients, 49 (23.8 %), 41 (19.9 %), and 116 (56.4 %) were stages I, II, and III, respectively, according to the seventh edition of the American Joint Commission on Cancer (AJCC) staging system. Both disease-free survival (DFS) and overall survival (OS) were significantly longer in patients with tumor marker response compared with nonresponse (61.5 vs. 37.6 months; P = 0.010 and 71.3 vs. 50.9 months; P = 0.008, respectively). Multivariate analyses showed that high CA19-9 level, early tumor marker response, and tumor, node, metastasis classification system stage were independent predictors of DFS and OS (P < 0.05).

Conclusions

Early CEA or CA19-9 normalization after radical gastrectomy is a strong prognostic factor for gastric cancer, especially in patients with high preoperative levels of tumor markers.  相似文献   
108.

Purpose

Recently, the American Joint Committee on Cancer (AJCC) 7th edition proposed new response criteria for neoadjuvant chemotherapy (NAC) in breast cancer. The purpose of this study was to evaluate the clinical usefulness of AJCC response criteria.

Methods

A total of 398 consecutive stage II or III breast cancer patients who received NAC were enrolled in this study. AJCC response criteria were as follows: (1) complete response (CR)—absence of invasive carcinoma in the breast and node; (2) partial response (PR)—decrease in either or both T or N stage; (3) no response (NR)—no change or increase in either or both T or N stage.

Results

Complete response, PR, and NR by AJCC criteria were 9.8, 59.3, and 30.7 %, respectively. Among the 398 patients, 337 patients were available for both paired pre- and post- breast MRI and chest CT. AJCC response criteria were significantly associated with RECIST criteria (P < 0.001). AJCC response was significantly associated with relapse-free survival (RFS) and overall survival (OS). The 5-year RFS rates were 89.6 % in CR, 74.1 % in PR, and 62.6 % in NR (P = 0.002). The 5-year OS rates were 97.4 % in CR, 88.6 % in PR, and 78.3 % in NR (P = 0.012). When adjusting potential prognostic factors, AJCC response was independently associated with RFS and OS.

Conclusions

AJCC response criteria for NAC in breast cancer have clinical usefulness in evaluating response of NAC, as well as predicting survival. AJCC response criteria can discriminate among patient subgroups with respect to survival.  相似文献   
109.

Background

Adenocarcinoma of esophagogastric junction (EGJ) is currently staged by the esophageal staging criteria according to the American Joint Committee on Cancer (AJCC) staging system, 7th edition. We compared the performance of 6th gastric (G6), 7th gastric (G7), and 7th esophageal (E7) staging systems.

Methods

A total of 202 curatively resected adenocarcinomas of EGJ were analyzed. Patient outcomes were assessed according to G6, G7, and E7 staging. Tumor invasion to the subserosal or serosa layer was regarded as invasion to the adventitia for E7 staging. Performance was measured based on monotonicity (decreasing survival with increasing stage), distinctiveness (survival difference between different stages), and homogeneity (homogenous survival in the same stage).

Results

Each staging system was monotonous except for T1-2N0 lesions of E7. This was related to the introduction of histologic grade in E7 staging. Distinctiveness in each staging system was variable. As for the homogeneity, patients whose disease was staged as Ib (E7) exhibited different survival when reassessed by G6 and G7; again, this was related to histologic grading. Patients with IIIb (G7) and IIIc (E7) disease had different survival when reassessed by G6 staging, reflecting the poorer survival of patients with more than 15 lymph node metastases.

Conclusions

Staging of EGJ cancer based on the current AJCC, 7th edition, criteria of esophageal cancer staging has several limitations. We recommend considering modifications of the following in future updates of the staging system: accurate anatomical definition of tumor depth, removal of histologic grade from staging parameters, and classification of more than 15 lymph node metastases as a highly advanced stage.  相似文献   
110.
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