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141.

Objective

This study aims to assess the orthodontic diagnostic skills, referral patterns, and the perceptions of orthodontic benefits of pediatric and general dentists in comparison with orthodontists.

Materials and methods

Two online surveys were e-mailed to pediatric dentists, general dentistry practitioners, and orthodontists registered as members of the Saudi Dental Society and the Saudi Orthodontic Society. The surveys included questions about the type of orthodontic treatment provided, referral trends, and timing; presumed benefits associated with successful orthodontic treatment; and diagnosis and treatment plans of seven cases representing different malocclusions.

Results

In total, 25 orthodontists, 18 pediatric dentists, and 14 general practitioners completed the survey. Only 38.8% of pediatric dentists and 7.1% of general practitioners reported that they practiced orthodontics clinically. The perceptions of the three groups toward the benefits of orthodontic treatment were comparable in the psychosocial areas. However, the orthodontists perceived significantly lesser effects of orthodontic treatment on the amelioration of temporomandibular disorder (TMD) symptoms. Pediatric dentists tended to rate the need and urgency of treatment higher, while general practitioners tended to rate the need of treatment lower. The selected treatment plans for three early malocclusion cases showed the greatest discrepancies between the orthodontists and the other two groups.

Conclusions

The orthodontists consistently and significantly downplayed the perceived benefit of orthodontic treatment to reduce TMD symptoms. Also, while there was a similarity in the diagnosis, there were notable differences in the proposed treatment approaches, perceived treatment need, and timing of intervention between the three groups of practitioners.  相似文献   
142.
Cutaneous leishmaniasis (CL) is a significant public health problem with increasing incidence, especially in extreme circumstances. In this study, we compared the sociodemographic and clinical characteristics of 685 Syrian CL patients afflicted by the Syrian conflict and 685 Turkish CL patients in 2012. Patient age, gender, duration of disease, lesion size, type, and localization were evaluated. The duration of CL disease in Syrian CL patients (4.5 ± 4.3 weeks) was shorter than that of Turkish CL patients (11.9 ± 9.7 weeks). The number of lesions was greater in Syrian patients (2.46 ± 2.43) than in Turkish patients (1.93 ± 1.47). Lesion sizes were comparable between both groups (Syrian, 11.2 ± 8.7 mm; Turkish, 10.7 ± 7.7 mm). In Syrian CL patients, nodular type lesions were the most common (325 patients, 49.1%), whereas, in Turkish CL patients, ulcer type lesions were the most common (352 patients, 51.5%). Our results indicate variations in the clinicoepidemiological features of CL between Turkish and Syrian patients within Sanliurfa province. This highlights the impact of social unrest and environmental conditions on the epidemiology of CL within this region. Approaches to prevention, control, and treatment of CL in these areas should take into consideration the emerging changes in clinicoepidemiological parameters of the disease.  相似文献   
143.
Management of interstitial cystitis/bladder pain syndrome (IC/BPS) remains a challenge due to poor understanding on its etiology. Complementary and alternative medicine (CAM), as an optional treatment, has been widely used, because no definitive conventional therapy is available. The different domain of CAM provides miscellaneous treatments for IC/BPS, which mainly include dietary modification, nutraceuticals, bladder training, biofeedback, yoga, massage, physical therapy, Qigong, traditional Chinese medicine and acupuncture. Clinical evidence has shown that each therapy can certainly benefit a portion of IC/BPS patients. However, the target patient group of each therapy has not been well studied and randomized, controlled trials are needed to further confirm the efficacy and reliability of CAM on managing IC/BPS. Despite these limitations, CAM therapeutic characteristics including non-invasive and effectiveness for specific patients allow clinicians and patients to realize multimodal and individualized therapy for IC/BPS.  相似文献   
144.
145.

Objectives:

To evaluate continuous positive airway pressure (CPAP) compliance and define predictors of CPAP compliance among Saudi patients with obstructive sleep apnea (OSA) after applying an educational program.

Methods:

This prospective cohort study included consecutive patients diagnosed to have OSA based on polysomnography between January 2012 and January 2014 in King Saud University, Riyadh, Kingdom of Saudi Arabia. All patients had educational sessions on OSA and CPAP therapy before sleep study, and formal hands-on training on CPAP machines on day one, day 7, and day 14 after diagnosis. The follow-up in the clinic was carried out at one, 4, and 10 months after initiating CPAP therapy. Continuous positive airway pressure compliance was assessed objectively. Logistic regression model was used to assess the predictors of CPAP adherence.

Results:

The study comprised 156 patients with a mean age of 51.9±12.1 years, body mass index of 38.4±10.6 kg/m2, and apnea hypopnea index of 63.7±39.3 events/hour. All patients were using CPAP at month one, 89.7% at month 4, and 83% at month 10. The persistence of CPAP-related side effects and comorbid bronchial asthma remained as independent predictors of CPAP compliance at the end of the study.

Conclusion:

With intensive education, support, and close monitoring, more than 80% of Saudi patients with OSA continued to use CPAP after 10 months of initiating CPAP therapy.Continuous positive airway pressure (CPAP) is a standard, safe, and efficacious treatment for obstructive sleep apnea (OSA), a common disorder with established harm to quality of life and adverse consequences for cardiovascular health.1 Obstructive sleep apnea is characterized by recurrent partial (hypopnea) or complete (apnea) upper airway obstruction during sleep. These recurrent respiratory events usually cause intermittent hypoxemia and sleep fragmentation.2 Recent data demonstrated that the estimated prevalence of moderate to severe OSA ranges from 10-17% in middle-aged and elderly men.3 In Saudi Arabia, 3 out of 10 middle-aged Saudi men and 4 out of 10 middle-aged Saudi women are at high risk of having OSA.4,5 The mainstay medical treatment for OSA is CPAP therapy.6 Among various available therapeutic modalities for OSA, CPAP remains the most effective treatment.6 Continuous positive airway pressure is a machine that applies positive airway pressure to the upper air passages via a mask fitted on the mouth or nose to keep the throat open.6 Previous studies in Western countries showed that OSA patients on CPAP therapy use their machines on average from 4.5 to 5.5 hours per night with compliance rates ranging from 30-85%.7,8 Several studies have been conducted to define factors that influence, or predict CPAP use and adherence, and reported conflicting results.6 Moreover, several studies reported that race might influence CPAP adherence. For example, available data suggest lower CPAP adherence among African Americans than Caucasians.9 An earlier study that assessed CPAP compliance subjectively (self-reports) among Saudi patients with OSA after 3 months of initiation of CPAP therapy revealed an overall compliance rate of 39%.10 However, self-reports have been shown to overestimate CPAP use by approximately one hour/night when compared with objectively measured CPAP use.11 In general, there are very few data on objectively assessed long-term CPAP compliance in the literature. Moreover, there is a lack of previous study objectively addressing the rate of CPAP compliance, the predictors of good compliance, and the side effects of CPAP treatment in Saudi OSA patients. Therefore, we established in our center an educational program for patients with OSA and easily accessible medical support, and close follow-up of CPAP compliance. This study was conducted to evaluate CPAP compliance and to define predictors of CPAP compliance among Saudi patients with OSA after applying the new educational program.  相似文献   
146.

Objectives:

To evaluate the clinical and biochemical characteristics of children with diabetic ketoacidosis (DKA).

Methods:

In this retrospective study conducted between June 2012 and November 2013 at the King Abdulaziz Medical City, Riyadh, Kingdom of Saudi Arabia, we evaluated pediatric DKA admissions from 1995-2008 (Phase 1). From the case files, we obtained information related to patients’ age, gender, weight, presenting complaints, serum biochemical profile, and management.

Results:

This study included 373 DKA admissions with a median age of 11 years (interquartile range [IQR]:8-13). The patients in the subgroup of age more than 10 years old had the highest proportion of admissions (n=250, 67%, p<0.000). The median duration of diagnosis of diabetes mellitus (DM) was 3 years (IQR:2-6). New-onset DM was 47%. Predominant precipitating cause was acute illness, mostly viral syndrome in 22% of all cases, and non-compliance to insulin regimen was in 79% of the diagnosed diabetic cases. Blood glucose, pH, anion gap, serum osmolality, serum potassium, and serum phosphate showed the highest change during the initial 6 hours of management, while trends of serum bicarbonate and blood urea nitrogen demonstrated a predominant change in the initial 12 hours.

Conclusion:

The notable findings in this study, such as, higher mean age of presentation, high rate of non-compliance to insulin as the cause of precipitation, and a high prevalence of abdominal pain at presentation should be followed up with further comparative studies.Diabetes mellitus (DM) is an endocrine disease affecting millions of children worldwide.1-3 Diabetic ketoacidosis (DKA) is one of the serious complication of diabetes in the pediatric population,4 and its prevalence increases by an annual rate of 3% worldwide.3 It is associated with significant risk of life threatening complications.5-8 The criteria for diagnosis of DKA in children by the International Society for Pediatric and Adolescent Diabetes describes DKA as blood glucose >11 mmol/L, venous pH <7.3, or bicarbonate <15 mmol/L, and ketonemia with ketonuria.9 Previous studies1,2 have reported characteristics of DKA patients based on different geographical areas. Overall, there is a paucity of literature on this particular aspect. The aim of this study was to assess pediatric patients presenting with DKA regarding aspects of demographics, presentation, investigations, and management in the Kingdom of Saudi Arabia (KSA).  相似文献   
147.
Elevated plasma levels of B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-pro-BNP) are seen in the setting of cardiac ischemia and are associated with adverse outcomes in patients with coronary artery disease. The mechanisms leading to natriuretic peptide elevation in patients with coronary artery disease, including the contribution of coronary atherosclerosis itself, have not been fully elucidated. Measurement of NT-pro-BNP, electron beam computed tomography, and cardiac magnetic resonance imaging were performed in 2,445 subjects from the Dallas Heart Study who were free of heart failure and renal insufficiency. Electron beam computed tomography-determined coronary artery calcium scores were categorized as none (<10), mild (> or =10 to <100), moderate (> or =100 to <400), and severe (> or =400). NT-pro-BNP levels increased significantly across increasing coronary artery calcium score categories (p <0.0001 for trend). In multivariate models adjusted for age, gender, race, body mass index, hypertension, history of myocardial infarction, angina, angiotensin-converting enzyme inhibitor use, beta-blocker use, left ventricular (LV) ejection fraction, and LV mass, higher coronary artery calcium scores remained independently associated with higher log NT-pro-BNP levels (p = 0.03). This association persisted in similar models excluding patients with low LV ejection fractions, LV hypertrophy, angina pectoris, and a history of myocardial infarction. In conclusion, these findings support the hypothesis that coronary atherosclerosis may directly influence the activation of the cardiac neurohormonal system.  相似文献   
148.
149.
Parkinson’s disease is characterized by accumulation of α-synuclein (αSyn). Release of oligomeric/fibrillar αSyn from damaged neurons may potentiate neuronal death in part via microglial activation. Heretofore, it remained unknown if oligomeric/fibrillar αSyn could activate the nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) inflammasome in human microglia and whether anti-αSyn antibodies could prevent this effect. Here, we show that αSyn activates the NLRP3 inflammasome in human induced pluripotent stem cell (hiPSC)-derived microglia (hiMG) via dual stimulation involving Toll-like receptor 2 (TLR2) engagement and mitochondrial damage. In vitro, hiMG can be activated by mutant (A53T) αSyn secreted from hiPSC-derived A9-dopaminergic neurons. Surprisingly, αSyn–antibody complexes enhanced rather than suppressed inflammasome-mediated interleukin-1β (IL-1β) secretion, indicating these complexes are neuroinflammatory in a human context. A further increase in inflammation was observed with addition of oligomerized amyloid-β peptide (Aβ) and its cognate antibody. In vivo, engraftment of hiMG with αSyn in humanized mouse brain resulted in caspase-1 activation and neurotoxicity, which was exacerbated by αSyn antibody. These findings may have important implications for antibody therapies aimed at depleting misfolded/aggregated proteins from the human brain, as they may paradoxically trigger inflammation in human microglia.

Parkinson’s disease (PD) is characterized by accumulation of α-synuclein (αSyn; encoded by the SNCA gene) (1). Release of oligomeric/fibrillar αSyn from damaged neurons may potentiate neuronal cell death in part via microglial activation (2, 3). Moreover, misfolded proteins in general are thought to interact with brain microglia, triggering microglial activation that contributes to neurodegenerative disorders, although microglial phagocytosis may also initially clear aberrant proteins to afford some degree of protection (2, 4). Additionally, in Alzheimer’s disease (AD), amyloid-β peptide (Aβ) is thought to trigger similar processes in microglia (57); however, the mechanism for this trigger is still poorly understood.Microglial cells contribute to neuroinflammation, specifically that mediated by the inflammasome. In particular, the nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) inflammasome has been associated with several neurodegenerative disorders, although other types of inflammation may also be important in this regard (8). The NLRP3 inflammasome is a multiprotein complex that responds to cell stress and pathogenic stimuli to promote activation of caspase-1, which in turn mediates maturation and release of proinflammatory cytokines, including interleukin-1β (IL-1β) and IL-18 (911). NLRP3 inflammasome activation is a two-step process, involving an initial priming step and a secondary trigger. Priming involves a proinflammatory stimulus, such as endotoxin, a ligand for Toll-like receptor 4 (TLR4), that increases the abundance of NLRP3 and promotes de novo synthesis of pro–IL-1β via nuclear factor κB (11). The secondary trigger promotes inflammasome complex assembly and caspase-1 activation that in turn mediates the cleavage of pro–IL-1β and subsequent release of mature IL-1β. There are various secondary triggers, including adenosine triphosphate (ATP), microparticles, and bacterial toxins, all of which somehow lead to mitochondrial damage and release of oxidized mitochondrial DNA (11). Neuroinflammation has been reported in both human PD and AD brains (1215), and NLRP3 inflammasome activation in particular has been observed in mouse models of PD and AD (7, 16). Importantly, in these PD models, dopaminergic (DA) neurons in the substantia nigra are resistant to damage in NLRP3-deficient mice compared with wild-type (WT) mice (16). Interestingly, a recent report identified an NLRP3 polymorphism that confers decreased risk in PD (17). Several groups have reported that fibrillar αSyn can activate the NLRP3 inflammasome in mice and in human monocytes (1822), but it remains unknown if human brain microglia can be activated in this manner. Critically, antibodies targeting misfolded proteins are being tested in human clinical trials for several neurodegenerative diseases, including AD and PD; however, it is still unclear how antibodies to αSyn might affect this inflammatory response. In this study, we characterized the response of human induced pluripotent stem cell (hiPSC)-derived microglia (hiMG) to oligomeric/fibrillar αSyn in vitro and in vivo, using engraftment of hiMG in humanized mice. We used these immunocompromised mice because they prevent human cell rejection and express three human genes that support human cell engraftment (23). We show that αSyn and, even more so, αSyn–antibody complexes activate the NLRP3 inflammasome. Moreover, this process is further sensitized by the presence of Aβ and its cognate antibodies. These observations are of heightened interest because recent studies have shown that both misfolded Aβ and αSyn are present in several neurodegenerative disorders such as AD and Lewy body dementia (LBD), a form of dementia that can occur in the setting of PD (2426).  相似文献   
150.

Background

Coronary computed tomography angiography (CCTA) is increasingly being used for the evaluation of coronary artery disease; however, radiation exposure remains a major limitation of its use.

Objective

To compare image quality and radiation exposure in two groups of patients undergoing CCTA using a 256-slice dual-source helical computed tomography scanner with high-pitch (FLASH) or prospective [step-and-shoot (SAS)] gating protocols.

Methods

A prospective, single-center study was performed in our cardiac center. In total, 162 patients underwent CCTA with either FLASH or SAS scanning protocols. Subjective image quality was graded on the basis of a four-point grading system (1, non-diagnostic; 2, adequate; 3, good; 4, excellent). Objective image quality was assessed using image signal, noise, and signal-to-noise ratio (SNR). The effective radiation dose was also estimated.

Results

The clinical and demographic characteristics of the patients in both groups were similar. The median age of the patients in both groups was 48.43?years, and males accounted for 63% and 68.7% of the FLASH and SAS groups, respectively. We found that the subjective image quality obtained with the FLASH protocol was superior to that obtained with the SAS protocol (3.35?±?0.6?mSv vs. 2.82?±?0.61?mSv; p?<?0.001). Image noise was higher in the FLASH group but was not statistically significant (25.0?±?6.13 vs. 24.0?±?6.8; p?=?0.10), whereas the signal and SNR was significantly higher with the FLASH protocol than with the SAS protocol [(469?±?116 vs. 397?±?106; p?>?0.001) and (21.6?±?8.7?mSv vs. 16.6?±?7.7?mSv; p?<?0.001), respectively]. Radiation exposure was 62% lower in the FLASH protocol than in the SAS protocol, (1.9?±?0.4?mSv vs. 5.12?±?1.8?mSv; p?<?0.001).

Conclusion

The use of 256-slice CCTA performed with the FLASH protocol has a better objective and subjective image quality as well as lower radiation exposure when compared with the use of prospective electrocardiography gating.  相似文献   
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