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61.
Idiopathic Sudden Sensorineural Hearing Loss (ISSHL) remains one of the major unsolved otologic emergencies. It is characterized by the onset of an unilateral sensorineural hearing loss developing within 24 hours, and averaging on pure tone audiogram at least 30 dB HL for three subsequent octave steps, with no marked vestibular symptoms and no identifiable cause. ISSHL is a syndrome covering several heterogeneous entities resulting from different pathogenetic mechanisms. At this time, the audiogram is the unique tool which may help clinicians to identify these entities and provide a classification based on 5 types of hearing loss. Numerous experimental and clinical studies have investigated the mechanisms by which infectious, ischemic, mechanic or immunologic insults may induce cochlear dysfunction. However, extrapolation to humans and rationale therapeutic approaches to ISSHL remain uncertain. SSHL being a diagnosis of exclusion, retrocochlear and neurologic etiologies should be eliminated. No argument allows to consider ISSHL a therapeutic emergency. More precisely, the experimental data presently available on cochlear physiology suggests that a treatment could have some chance to be effective if undertaken within minutes following the onset of ISSHL, a condition never encountered in daily practice. Conversely, it is not justifiable to impute the absence of hearing recovery to a delay in therapy. The various therapeutic strategies currently recommended are highly empirical and should be questionned in terms of cost-effectiveness, the most common being high-dose corticosteroids. New investigation tests are required for improving our approach to ISSHL.  相似文献   
62.
目的观察耳蜗外毛细胞发生凋亡时听力改变情况.方法对20只豚鼠药物造模,诱发耳蜗外毛细胞发凋亡.应用TUNEL技术观察凋亡表达,测试ABR阈值观察听力变化.结果应用丁胺卡那霉素1天即可诱发豚鼠耳蜗外毛细胞发生凋亡,连续应用3d,耳蜗外毛细胞凋亡呈强阳性表达,但ABR阈值无明显改变;随着用药时间延长,凋亡细胞数目增加,甚至出现部分毛细胞缺失现黎,此时ABR阈值明显升高.结论耳蜗外毛细胞发生凋亡早期对豚鼠听力无明显影响,随着耳毒性药物应用时间延长,豚鼠ABR阈值升高可能存在两种原因毛细胞凋亡或毛细胞坏死.  相似文献   
63.
徐芬  巴鹏飞  张树军  罗星  黄瑾 《农垦医学》2007,29(3):161-164
目的:筛选neuritin高表达及低表达细胞株,为进一步探讨neuritin在不同组织细胞生长发育过程中的作用奠定基础.方法和结果:分别利用RT-PCR与免疫组化技术在mRNA水平及蛋白水平,检测了11种人类细胞株中neuritin的表达情况,发现不仅在多种正常细胞中有表达,而且在部分肿瘤细胞中也有表达.结论:成功筛选出了neuritin高表达及低表达细胞株.  相似文献   
64.
Thiam S  LeFevre AM  Hane F  Ndiaye A  Ba F  Fielding KL  Ndir M  Lienhardt C 《JAMA》2007,297(4):380-386
Context  Poor adherence to treatment remains a major obstacle to efficient tuberculosis (TB) control in developing countries. Innovative strategies to improve access and adherence to treatment are needed. Objectives  To assess the effectiveness of a contextualized intervention strategy aimed at improving patients' adherence to treatment and to evaluate its impact on TB control in a resource-poor country in Africa with prevalent TB infection. Design, Setting, and Patients  A cluster randomized controlled trial, conducted between June 2003 and January 2005, at 16 government district health centers in Senegal. Patients older than 15 years with newly diagnosed sputum smear–positive pulmonary TB were randomly assigned to the intervention or control group. Intervention  The intervention strategy included reinforced counseling through improved communication between health personnel and patients, decentralization of treatment, choice of directly observed therapy (DOT) supporter by the patient, and reinforcement of supervision activities. In the control group, the usual TB control program procedures remained unchanged. Main Outcome Measure  Proportion of patients successfully completing the 8-month course of treatment and the proportion of patients defaulting from treatment. Results  A total of 1522 patients were recruited into the study. Treatment was successful for 682 (88%) of 778 patients recruited in the intervention group, and for 563 (76%) of 744 patients recruited in the control group (adjusted risk ratio [RR], 1.18; 95% confidence interval [CI], 1.03-1.34). The proportion of patients defaulting was reduced in the intervention group to 5.5% (n = 43) compared with 16.8% (n = 125) in the control group (adjusted RR, 0.43; 95% CI, 0.21-0.89). Conclusion  The intervention package based on improved patients counseling and communication, decentralization of treatment, patient choice of DOT supporter, and reinforcement of supervision activities led to improvement in patient outcomes compared with the usual TB control procedures. This approach may be generalized in the context of TB control programs in resource-poor countries. Trial Registration  clinicaltrials.gov Identifier: NCT00412009   相似文献   
65.
OBJECTIVE: To evaluate the relationship between frontal sinusitis and the localization of the frontal sinus outflow tract medial or lateral to the superior attachment of the uncinate process (UP). DESIGN: A retrospective anatomical and clinical study. SETTING: An ear, nose, and throat clinic in i?li Etfal Teaching and Research Hospital, Istanbul, Turkey. PATIENTS: Paranasal sinus computed tomographic scans of 486 sides of the frontal sinuses (hereafter referred to as sides) of 243 patients who had chronic sinusitis were evaluated. In 125 sides (26%), the superior attachment of the UP could not be identified. In the remaining 361 sides (74%), the prevalence of superior attachment of UP types and the presence of frontal sinusitis in each side were recorded. Localization of the frontal sinus outflow tract was determined according to the superior attachment of the UP. Drainage of the frontal sinus to the middle meatus (medial to the superior attachment of the UP [types 1-3]) was classified as group 1, and drainage of the frontal sinus to the ethmoid infundibulum (lateral to the superior attachment of the UP [types 4-6]) was classified as group 2. RESULTS: Frontal sinusitis was found in 125 (35%) of 361 sides. The distribution of frontal sinusitis was 97 (41%) of 237 in group 1 and 28 (23%) of 124 in group 2. Group 1 drainage had a statistically significant presence of frontal sinusitis (chi(2) = 12.11; P<.001). The prevalence of superior attachment of UP types was 63% for type 1/2, 3% for type 3, 12% for type 4, 14% for type 5, and 8% for type 6. CONCLUSIONS: Frontal sinus outflow tract, which is medial to the superior attachment of the UP, is more common than the lateral one. There is a statistically significant relation between the presence of frontal sinusitis and the frontal sinus outflow tract, which is medial to the superior attachment of the UP.  相似文献   
66.
Recurrent aphthous stomatitis (RAS) has a multifactorial etiopathogenesis, an interaction between predisposing factors and/or systemic conditions and immunological components in genetically predisposed subjects. The Mediterranean fever (MEFV) gene has already been identified as being responsible for familial Mediterranean fever. Because the association between MEFV gene mutations and Behçet's disease has been reported before in several studies, we considered that the role of MEFV gene mutations should be studied in patients with RAS, because of the clinical similarities of both diseases. The aim of this study was to explore the frequency and clinical significance of MEFV gene mutations in a cohort of Turkish patients with RAS. The study population comprised 100 unrelated patients with a clinical diagnosis of RAS and 156 healthy controls. Genomic DNA was isolated and genotyped using polymerase chain reaction and restriction fragment length polymorphism for the four MEFV gene mutations (M694V, M680I, V726A and E148Q). There were statistically significant differences of the MEFV gene mutation carrier rates and allele frequencies between RAS patients and healthy controls (P = 0.042, odds ratio [OR] = 1.9, 95% confidence interval [CI] = 1.01–3.41; and P = 0.039, OR = 1.8, 95% CI = 1.02–3.14, respectively). Even if it is not statistically significant, the E148Q allele frequency was higher in patients with RAS than the control group. A statistically significant increased prevalence of MEFV variants in RAS patients was found. This is the first study to report that missense mutations of MEFV is associated with RAS in the Turkish population.  相似文献   
67.

Background

Chronic inflammatory diseases such as psoriasis, rheumatoid arthritis, and inflammatory bowel diseases have been reported to be associated with the development of metabolic syndrome (MetS), which is characterized by central obesity, elevated triglycerides (TG), reduced high-density lipoproteins (HDL), impaired fasting blood glucose (FBG), and hypertension. Behçet disease (BD) is a chronic, immuno-inflammatory disease with multisystemic involvement.

Objective

The aim of this study was to investigate the prevalence and risk factors for MetS in patients with BD.

Methods

All patients had BD according to the criteria of the International Study Group. Diagnosis of MetS was established according to National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria. Mean waist circumference, body mass index (BMI), FBG, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), total cholesterol, HDL, very low-density lipoprotein (VLDL), low-density lipoprotein (LDL), TG, systolic BP, and diastolic BP were measured and analyzed.

Results

A total of 86 patients and 72 healthy controls were included. MetS was detected in 35.4 % of patients and 20 % of controls (p = 0.04). Patients with BD had a 2.67-fold higher risk for MetS than healthy controls (p < 0.05). Significant risk factors for developing MetS according to multivariate analyses were BD, age, and BMI. Age at onset of the disease, duration of disease, BMI, gastrointestinal system involvement, and neurological involvement were correlated with increased MetS risk (p < 0.05). MetS tended to increase with age and the duration of the disease and was higher in women under the age of 40 years compared with healthy controls in the same age group.

Conclusion

All BD patients should be closely monitored for hypertension, hyperlipidemia, and diabetes mellitus to avoid MetS development.  相似文献   
68.
Structural features of 59 progressive nevuses of the conjunctiva were studied. The proliferation of the epithelium and melanocytes is partially compensated by spontaneous regression of the nevus structures. The growth of a nevus is structurally similar to tumor growth, but the nevuses lack the melanocyte dysplasia, the main sign of malignant degeneration. The immune reactions are involved in the tissue restructuring of the growing nevus. Permanent foci of photoelastosis reflect the significance of ultraviolet exposure as a factor of risk of the nevuses progress.  相似文献   
69.
The aim of this study was to investigate the effects of the application of gaseous ozone and Nd:YAG laser on glass‐fibre post bond strength. Forty‐two madibular premolar roots were cut, endodontically instrumented and irrigated with 2.5% NaOCl. Post spaces were prepared and roots were divided into three groups (n = 14). The antimicrobial pretreatment was conducted as follows: gaseous ozone, Nd:YAG laser and control (no additional disinfection methods). Scanning electron microscope analysis was made for each group (n = 2). A resin cement was used for luting the posts. For push‐out test, each root was cut horizontally (two cervical, two middle and two apical). Statistical analyses were performed with one‐way anova (α = 0.05). Fracture types were observed. There was no statistically significant difference between the groups (P > 0.05). There were statistically significant differences in cervical and apical segments of laser and control groups (P < 0.05). The disinfection of the post spaces with Nd:YAG laser and ozone had no adverse effects on bond strength of glass‐fibre post.  相似文献   
70.
During infection, interactions between Candida albicans and oral epithelial cells result in oral epithelial cell death. This is clinically manifested by the development of oral mucosal ulcerations generally associated with discomfort. In vitro studies have shown that C. albicans induces early apoptotic alterations in oral epithelial cells; however, these studies have also shown that treatment of infected cells with caspase inhibitors does not prevent their death. The reasons for these contradictory results are unknown and it is still not clear if C. albicans stimulates oral epithelial signaling pathways that promote apoptotic cell death. Activation of specific death pathways in response to microbial organisms plays an essential role in modulating the pathogenesis of a variety of infectious diseases. The aim of this study was to (i) characterize C. albicans‐induced apoptotic morphological alterations in oral epithelial cells, and (ii) investigate the activation of apoptotic signaling pathways and expression of apoptotic genes during infection. Candida albicans induced early apoptotic changes in over 50% of oral epithelial cells. However, only 15% of those showed mid‐late apoptotic alterations. At the molecular level, C. albicans caused a loss of the mitochondrial transmembrane potential and translocation of mitochondrial cytochrome c. Caspase‐3/9 activities increased only during the first hours of infection. Moreover, poly[ADP ribose] polymerase 1 was cleaved into apoptotic and necrotic‐like fragments. Finally, five anti‐apoptotic genes were significantly upregulated and two pro‐apoptotic genes were downregulated during infection. Altogether, these findings indicate that epithelial apoptotic pathways are activated in response to C. albicans, but fail to progress and promote apoptotic cell death.  相似文献   
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