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41.
Americans are much more likely to be socially connected to copartisans, both in daily life and on social media. However, this observation does not necessarily mean that shared partisanship per se drives social tie formation, because partisanship is confounded with many other factors. Here, we test the causal effect of shared partisanship on the formation of social ties in a field experiment on Twitter. We created bot accounts that self-identified as people who favored the Democratic or Republican party and that varied in the strength of that identification. We then randomly assigned 842 Twitter users to be followed by one of our accounts. Users were roughly three times more likely to reciprocally follow-back bots whose partisanship matched their own, and this was true regardless of the bot’s strength of identification. Interestingly, there was no partisan asymmetry in this preferential follow-back behavior: Democrats and Republicans alike were much more likely to reciprocate follows from copartisans. These results demonstrate a strong causal effect of shared partisanship on the formation of social ties in an ecologically valid field setting and have important implications for political psychology, social media, and the politically polarized state of the American public.  相似文献   
42.
FH is a genetic disorder characterized by an increase in serum LDL and total cholesterol values. The afflicted patients are at increased risk of premature atherosclerosis and myocardial infarction. Different treatment modalities are present, including pharmacological agents and surgical procedures. The most effective method of therapy in refractive cases is liver transplantation. Herein, we report our experience on 36 cases of patients with FH undergoing liver transplantation in our center, the main referral center of liver transplantation in Iran. The clinical findings, hospital courses, post‐operative complications, and patient follow‐up are also described.  相似文献   
43.

Background:

Testicular torsion (TT), or twisting of the testicle resulting in a strangulation of the blood supply, occurs in men whose tissue surrounding the testicle is not well attached to the scrotum. It is important to emphasize that testicular torsion is a medical emergency.

Objectives:

The aim of this study is to evaluate the second look exploration and outcomes in TT.

Patients and Methods:

Seventy boys out of 124 patients underwent early exploration and 48 hours later second look exploration due to TT. All patients were checked with preoperative color-doppler ultrasonography (CDU) and intraoperative bleeding test. Data included age at admission, side of pathology, relation of TT with season of year, duration of preoperative history, degree of testicular torsion, CDU findings, and degree of bleeding; results of second look exploration, follow-up, and outcomes were analyzed.

Results:

Totally 70 patients were included in this study within five years, of which mean age was 28.6 ± 32.9 months (range 1 to 144), 48% of our patients had nausea and vomiting. Preoperative CDU showed absent/weak flow in 50 (71%) cases. Winter showed most frequently (44%) referred cases of testicular torsion. Orchidopexy was performed in 44 (63%) and orchidectomy in 26 (37%) cases after second look exploration. Mean follow-up duration was 3.1 ± 1.4 years. 4 (9%) cases in orchidopexy group developed testicular atrophy during follow-up, all four cases had a history of longer than 12 hours and grade II testicular bleeding test intra-operatively. Other orchidopexy patients salvaged. 26 patients, who were in grade III, underwent orchidectomy in second look exploration.

Conclusions:

TT requires emergency attention. The ischemia time of the testis is traditionally after 6 hours, and imaging or other diagnostic modality should not be a cause of delay. Early surgical exploration is modality of choice, and second look exploration after 48 hours can be more effective and salvageable in these patients.  相似文献   
44.
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   
45.

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   
46.

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   
47.

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   
48.
49.
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   
50.
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   
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