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51.
This study investigates the potential application of an efficient, easily recoverable and reusable magnetically separable Fe3O4/KCC-1/APTPOSS nanoparticle-supported salen/Pd(ii) catalyst for C–C and C–H cross-couplings. The Fe3O4/KCC-1/APTPOSS/salen/Pd(ii) MNPs were thoroughly characterized by using TEM, FE-SEM, TGA, XRD, VSM, FT-IR, ICP-MS, and BET. This observation was exploited in the direct and selective chemical reaction of 2-acetyl-benzaldehyde with cyclopentadiene for the synthesis of pentafulvene. The recycled catalyst has been analyzed by ICP-MS showing only minor changes in the morphology after the reaction, thus confirming the robustness of the catalyst.

This study investigates the potential application of an efficient, easily recoverable and reusable magnetically separable Fe3O4/KCC-1/APTPOSS nanoparticle-supported salen/Pd(ii) catalyst for C–C and C–H cross-couplings.  相似文献   
52.

Background

As one of the most common work-related musculoskeletal disorders and postural deviations, forward head posture (FHP), is considered to lead to muscle imbalance.

Objectives

The aim of this study is to investigate the bilateral cross-sectional area (CSA) of the deep neck flexor muscles at rest and during five stages of the craniocervical flexion (CCF) test in individuals with FHP and the controls with normal head posture.

Methods

Eighteen students with FHP and 18 controls with normal head posture, all females aged 18–35 years, participated in this study. Participants were categorized into two groups based on their craniovertebral angle. The CSA of the deep neck flexors was measured using ultrasonography while participants lay supine on the table with a pressure biofeedback unit placed under their necks in order to let the examiner measure the CSA of the muscles during rest and five stages of the CCF test including 22, 24, 26, 28, and 30 mmHg of the pressure biofeedback unit.

Results

A significant effect of contraction level was observed in both groups, indicating significant increases of the CSA of the deep neck flexors during contraction (F = 64.37, P < 0.001). No significant difference was evident for the CSA of the deep neck flexors between the groups, although the increase in the CSA of the deep neck flexors was up to 28 mmHg in the normal head posture group compared to 26 mmHg in the FHP group.

Conclusions

The results of the present study showed no significant difference between the performance of the deep neck flexors during the CCF test in FHP and normal head posture individuals, which challenge the common belief of the deep neck flexors weakness in individuals sustaining FHP.  相似文献   
53.

Objectives

The present study seeks to answer the following two questions: Are nurse educators satisfied with their job? What are the factors affecting job satisfaction in nurse educators?

Background

Nurse educators' job satisfaction has a significant role in the efficiency and performance of nursing schools. Identifying the factors affecting job satisfaction in nurse educators is essential to improving their quality of work and ultimately training efficient students and nurses.

Evaluation

The present systematic review searched databases including PubMed, Medline, Cochrane Library, Scopus, Web of Science, Science Direct, ProQuest, Google Scholar and SID for articles published up to April 24, 2018, using keywords including Nurse Teachers, Nurse Faculty, Academic Nurses, Nurse Educators, Dis/Satisfaction, Work, Career, Professional, Practice and Job. Of the total of 971 articles extracted, only 74 remained for the final analysis after the qualitative assessment.

Key issue

The articles included in the analysis investigated the relationship between job satisfaction and its contributing factors rather than providing an accurate report on job satisfaction. Nonetheless, a number of the articles had reported fairly to very favorable levels of job satisfaction. The factors affecting nurse educators' job satisfaction were categorized into six levels, including personal, organizational, managerial, academic, professional and economic levels.

Conclusion

Although job satisfaction was reported relatively well in the nurse educators, this condition depends on several indices. The lack of positive steps toward job satisfaction in nurse educators leads to destructive behaviors and turnover intentions; meanwhile, it is satisfied educators who can train competent nurses.  相似文献   
54.

Objectives

Urinary tract infection caused by uropathogenic Escherichia coli (UPEC) strains is one of the most important infections in the world. UPEC encode widespread virulence factors closely related with pathogenesis of the bacteria. The purpose of this study was to evaluate the presence of different phenotypic virulence markers in UPEC isolates and determine their correlation with antibiotic resistance pattern.

Methods

UPEC isolates from patients with different clinical symptoms of UTI were collected and screened for biofilm and hemolysin production, mannose resistant, and mannose sensitive hemagglutination (MRHA and MSHA, respectively). In addition, antimicrobial resistance pattern and ESBL-producing isolates were recorded.

Results

Of the 156 UPEC isolates, biofilm and hemolysin formation was seen in 133 (85.3%) and 53 (34%) isolates, respectively. Moreover, 98 (62.8%) and 58 (37.2%) isolates showed the presence of Types 1 fimbriae (MSHA) and P fimbriae (MRHA), respectively. Our results also showed a relationship between biofilm formation in UPEC isolated from acute cystitis patients and recurrent UTI cases. Occurrence of UTI was dramatically correlated with the patients'' profiles. We observed that the difference in antimicrobial susceptibilities of the biofilm and nonbiofilm former isolates was statistically significant. The UPEC isolates showed the highest resistance to ampicillin, tetracycline, amoxicillin, and cotrimoxazole. Moreover, 26.9% of isolates were ESBL producers.

Conclusion

This study indicated that there is a relationship between the phenotypic virulence traits of the UPEC isolates, patients'' profiles, and antibiotic resistance. Detection of the phenotypic virulence factors could help to improve understanding of pathogenesis of UPEC isolates and better medical intervention.  相似文献   
55.
56.
Clinical Rheumatology - Rheumatoid arthritis is a chronic inflammatory and systemic autoimmune disease associated with synovial fluid inflammatory lesions and articular changes. The aim of the...  相似文献   
57.
Lung function was studied in 24 patients with advanced mitral stenosis scheduled for mitral valve replacement (MVR), and revealed an obstructive ventilatory pattern [rewording of this sentence OK] . Forty per cent of the patients had a forced expiratory volume in 1 s (FEV1)<60% of that predicted in the preoperative period. Twenty-five per cent of those operated upon showed a similar pattern up to 110 weeks postoperatively. A blind study of the effect of placebo and β2 agonist (salbutamol) inhalation was performed preoperatively and 6 months postoperatively, to evaluate the reversibility of airflow obstruction in these patients, flow volume curve and body plethysmographic measurement of airway resistance (Rex) and intrathoracic gas volume (VTG). Patients in the pre and postoperative period showed a significant difference between the placebo and the β2 agonist responses for FEV1, FEV1 as percentage of FVC (FEV1% FVC), peak expiratory flow rate (PEFR), flow rate of 50% of expiratory vital capacity ([¨max50), Rex and VTG (P<0.001). We conclude that salbutamol inhalation improves obstructive impairment in patients with MVR pre- and postoperatively.  相似文献   
58.

Purpose of Review

Outline recent epidemiologic data regarding hypertension in developing countries, distinguish differences from developed countries, and identify challenges in management and future perspectives.

Recent Findings

Increased sugar intake, air and noise pollution, and low birth weight are emerging hypertension risk factors. The major challenges in management are difficulties in accurate diagnosis of hypertension and adequate blood pressure control.

Summary

In contrast to developed countries, hypertension prevalence rates are on the rise in developing countries with no improvement in awareness or control rates. The increasing burden of hypertension is largely attributable to behavioral factors, urbanization, unhealthy diet, obesity, social stress, and inactivity. Health authorities, medical societies, and drug industry can collaborate to improve hypertension control through education programs, public awareness campaigns, legislation to limit salt intake, encourage generic drugs, development and dissemination of national guidelines, and involving nurses and pharmacists in hypertension management. More epidemiologic data are needed in the future to identify reasons behind increased prevalence and poor blood pressure control and examine trends in prevalence, awareness, treatment, and control. National programs for better hypertension control based on local culture, economic characteristics, and available resources in the population are needed. The role of new tools for hypertension management should be tested in developing world.
  相似文献   
59.
The aim of this study was to describe epidemiologic characteristics of intestinal parasites in a population in south of Tehran, Iran. A retrospective cross-sectional study of patients with suspicious intestinal parasitic infections referred to the Zakaria Razi Laboratory in Shahre-Ray, southern Tehran, Iran, was conducted from April 21, 2004 to October 20, 2005. All stool samples were examined and socio-demographic informations were retrieved. Of 4,371 referred patients, 466 (239 males and 227 females) were laboratory diagnosed with intestinal parasites, with a period prevalence of 10.7%. Blastocystis hominis (B. hominis) and Giardia lamblia (G. lamblia) were the most frequent intestinal parasites. More than half of patients aged (3) 18 years had a low level of educational attainment (e.g. illiterate, primary school, high school) (170/331, 54.1%). Further, majority of patients were homemakers (42.3%, 140/331) or workers (28.1%, 93/331) employed in various business settings such as food industry and construction. Findings of this study showed that intestinal parasitic infections are still a major public health challenge in Iran that needs to be addressed. We believe that public education, improving sanitation conditions of underdeveloped areas/communities, community involvement, and supporting evidence-based practice/programs are the major keys to success in preventing the spread of intestinal parasitic infections in Iran.  相似文献   
60.
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