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551.

Background

This paper reviews the types, prevalence and demographic distribution of maxillofacial tumors, cysts and tumor-like lesions in a Nigerian population.

Methods

A retrospective analysis of the medical records and histological reports of patients with oral and maxillofacial tumors and cystic lesions who presented to the Maxillofacial Unit of our institution over an eleven year period was undertaken. Information on demographics, histological diagnosis and clinical presentation were obtained and analyzed. A p value of less than 0.05 was considered significant.

Results

A total o:f 146 patients, aged 5–70 years (mean 30.5± 12.9) were seen over the period of study. There were 96 males (65.8%) and 50 females (34.2%) giving a male to female ratio of almost 2:1. Benign tumors accounted for 124, 86.3% and malignant tumors (22, 13.7%). Ameloblastoma was the most prevalent benign tumor observed (53, 36.3%) while squamous cell carcinoma was the most common malignant tumor. The peak age of ameloblastoma was the fourth decade and squamous cell carcinomas the sixth and seventh decades of life. Jaw swellings were the most common presentation (98, 67.1%), followed by pain (23, 15.9). The duration of symptoms on presentation ranged from 1 to 96 months (mean 23.32 ±15.72) and this was not different for malignant or benign tumors (P=0.886).

Conclusion

Late presentation still remains the main challenging factor in the early detection and management of maxillofacial tumors in our environment. More awareness campaign is necessary, especially at the primary health care level, to educate the populace on the need for early presentation at treatment centers.  相似文献   
552.
553.
Background/aim Acetaminophen (APAP), used in the composition of thousands of preparations, is the most commonly used analgesic and antipyretic drug. The present study aimed to investigate the potential protective effects of the betulinic acid (BA) treatment through an APAP-induced hepatotoxicity rat model, using inflammatory, biochemical, and histopathological parameters. Materials and methodsThe study consisted of four groups: control group, APAP group, BA group, and APAP+BA group. Experimental studies continued for fifteen days. Serum samples were analysed for glucose, total cholesterol (TChol), triglyceride (TG), low density lipoprotein (LDL), high density lipoprotein (HDL), aspartate amino transferase (AST), malondialdehyde (MDA), toll-like receptor-9 (TLR-9), nuclear factor kappa B (NF-κB), and interleukin-18 (IL-18).ResultsTLR9, IL-18, NF-κB, and MDA levels increased significantly in liver injury groups. These increases considerably decreased by the BA treatment. All groups showed immunopositivity for 8-hydroxy-2’–deoxyguanosine (8-OHdG) and interleukin (IL-1β) in the hepatocytes, inflammatory cells, and epithelial cells of bile ducts. Conclusion BA can be used as an effective agent in the prevention and treatment of acute liver diseases due to its inhibitory properties in multiple pathways and its potent antioxidant effects.  相似文献   
554.

Objectives

The aim of the study was to quantify the benefits (life expectancy gains) and risks (efavirenz‐related teratogenicity) associated with using efavirenz in HIV‐infected women of childbearing age in the USA.

Methods

We used data from the Women's Interagency HIV Study in an HIV disease simulation model to estimate life expectancy in women who receive an efavirenz‐based initial antiretroviral regimen compared with those who delay efavirenz use and receive a boosted protease inhibitor‐based initial regimen. To estimate excess risk of teratogenic events with and without efavirenz exposure per 100 000 women, we incorporated literature‐based rates of pregnancy, live births, and teratogenic events into a decision analytic model. We assumed a teratogenicity risk of 2.90 events/100 live births in women exposed to efavirenz during pregnancy and 2.68/100 live births in unexposed women.

Results

Survival for HIV‐infected women who received an efavirenz‐based initial antiretroviral therapy (ART) regimen was 0.89 years greater than for women receiving non‐efavirenz‐based initial therapy (28.91 vs. 28.02 years). The rate of teratogenic events was 77.26/100 000 exposed women, compared with 72.46/100 000 unexposed women. Survival estimates were sensitive to variations in treatment efficacy and AIDS‐related mortality. Estimates of excess teratogenic events were most sensitive to pregnancy rates and number of teratogenic events/100 live births in efavirenz‐exposed women.

Conclusions

Use of non‐efavirenz‐based initial ART in HIV‐infected women of childbearing age may reduce life expectancy gains from antiretroviral treatment, but may also prevent teratogenic events. Decision‐making regarding efavirenz use presents a trade‐off between these two risks; this study can inform discussions between patients and health care providers.  相似文献   
555.

Background and purpose

As a combination of 5-HT selective reuptake inhibitor (SSRI) with 5-HT1A receptor antagonism may yield a rapidly acting antidepressant, WAY-211612, a compound with both SSRI and 5-HT1A receptor antagonist activities, was evaluated in preclinical models.

Experimental approach

Occupancy studies confirmed the mechanism of action of WAY-211612, while its in vivo profile was characterized in microdialysis and behavioural models.

Key results

WAY-211612 inhibited 5-HT reuptake (Ki = 1.5 nmol·L−1; KB = 17.7 nmol·L−1) and exhibited full 5-HT1A receptor antagonist activity (Ki = 1.2 nmol·L−1; KB = 6.3 nmol·L−1; Imax 100% in adenyl cyclase assays; KB = 19.8 nmol·L−1; Imax 100% in GTPγS). WAY-211612 (3 and 30 mg·kg−1, po) occupied 5-HT reuptake sites in rat prefrontal cortex (56.6% and 73.6% respectively) and hippocampus (52.2% and 78.5%), and 5-HT1A receptors in the prefrontal cortex (6.7% and 44.7%), hippocampus (8.3% and 48.6%) and dorsal raphe (15% and 83%). Acute or chronic treatment with WAY-211612 (3–30 mg·kg−1, po) raised levels of cortical 5-HT approximately twofold, as also observed with a combination of an SSRI (fluoxetine; 30 mg·kg−1, s.c.) and a 5-HT1A antagonist (WAY-100635; 0.3 mg·kg−1, s.c). WAY-211612 (3.3–30 mg·kg−1, s.c.) decreased aggressive behaviour in the resident-intruder model, while increasing the number of punished crossings (3–30 mg·kg−1, i.p. and 10–56 mg·kg−1, po) in the mouse four-plate model and decreased adjunctive drinking behaviour (56 mg·kg−1, i.p.) in the rat scheduled-induced polydipsia model.

Conclusions and implications

These findings suggest that WAY-211612 may represent a novel antidepressant.  相似文献   
556.
目的了解精神卫生防治机构医务人员的工作现状、满意度水平以及对精神卫生防治工作的建议,分析影响满意度的主要因素,为针对性的制定相关政策和采取相应措施提供科学依据。方法1成立调研组:2抽取两所县级精神卫生机构的医务人员代表召开座谈会;3发放无记名调查问卷,使用SPSSI1.5统计软件进行数据处理。结果调查结果显示:医务人员对工作现状满意程度不高,特别是在工作压力、社会地位、工作待遇、工作环境等方面满意度较低,且满意度与学历、职称、岗位及工龄有关,其差异有统计学意义。结论应根据医务人员对工作的满意度情况,分别采取针对性的管理措施及激励机制,提高他们的工作积极性,从而提高医疗服务质量,促进精神卫生事业的健康发展。  相似文献   
557.
目的总结同期胰肾联合移植(SPK)术的治疗效果和经验。方法自2002年1月至2003年9月,以SPK术治疗胰岛素依赖型糖尿病(IDDM)合并终末期肾病(ESRD)患者12例。每例受者接受来自同一供者的胰腺和肾脏,移植肾以经典方法植入左侧盆腔,胰腺植于右下腹。1例移植胰腺静脉与受者门静脉系统吻合,11例与体静脉系统吻合。胰腺外分泌引流方法为:3例移植物十二指肠段与受者十二指肠吻合,9例与空肠上段吻合。术前应用甲泼尼龙及抗胸腺细胞球蛋白作为免疫诱导,术后以他克莫司、霉酚酸酯和泼尼松三联抗排斥药物维持。结果术后平均随访时间23个月,受者、移植胰腺和移植肾的存活率分别为100%、91.7%和91.7%。1例再次行SPK术的受者,术后出现了超急性排斥反应,且未能逆转,于术后13d切除移植物;其余11例首次行SPK术的受者中,3例(28.3%)出现急性排斥,均获成功纠治。2例受者术后移植肾功能延迟恢复,行过渡性透析。11例首次行SPK术的移植胰腺术后立即发挥了功能,分别于术后1~5d内停用胰岛素。结论同期胰肾联合移植是胰岛素依赖型糖尿病合并终末期肾病患者的一种安全而有效的治疗方法。  相似文献   
558.
Focal and confluent areas of periventricular hyperintensity have been reported on magnetic resonance (MR) images in 30% of patients over 60 years of age. In order to better understand the pathologic basis of these lesions, the authors studied 14 formalin-fixed brains with MR imaging. Multiple focal areas of hyperintensity were identified in the periventricular white matter in three of the 14 brains studied (21%). Subsequent gross and microscopic pathologic examination of both hyperintense and normal-intensity areas was performed on 87 tissue sections. The larger lesions were characterized centrally by necrosis, axonal loss, and demyelination and therefore represent true infarcts. Reactive astrocytes oriented along the degenerated axons were identified at distances of up to several centimeters from the central infarct. This is called isomorphic gliosis and is associated with increased intensity on T2-weighted images that increases the apparent size of the central lesion.  相似文献   
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