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91.
An analysis of 6 patients with overriding atrioventricular valve was performed in order to correlate the anatomic and angiographic features of this malformation. The atrial arrangement was usual (situs solitus) in each patient. The ventricular chambers were normally related in 4 and the mirror image of normal in 2. The atrioventricular connexion was concordant in parallel fashion in 4, discordant in 1 and double inlet left ventricle in 1 heart. In 2 of 4 hearts with concordant atrioventricular connexion, the right atrioventricular valve (tricuspid) overrode the septum and connected partially to the left ventricle. In 2, the left atrioventricular valve (mitral) overrode the septum and partially connected with the right ventricle. One heart with discordant atrioventricular connexion had its right atrioventricular valve (mitral) overriding the septum. The remaining heart with double inlet left ventricle had an overriding left atrioventricular valve. Each overriding atrioventricular valve had its "septal" leaflet (the one committed to the contralateral ventricle) divided into 2 segments by a large cleft. Ventricular septal defects at different locations were present in all cases. The ventriculoarterial connexion was double outlet right ventricle in 5 patients and was discordant in 1. Malalignment of the atrial and ventricular septa was present to some degree in all cases. This was well depicted on ventriculograms in four chamber view in those with an overriding tricuspid valve. It was not detected in those with an overriding mitral valve. The displaced leaflets of the overriding and/or stradding valve had a vertical motion on cineangiograms similar to those observed in atrioventricular septal defects. Abnormal morphology and motion of the septal leaflet of the overriding atrioventricular valve and malalignment of the atrial and ventricular septal structures were the most important angiographic findings in this series.  相似文献   
92.

Background

Alcohol use is increasing in North East India and is important to estimate the influence of these changes in the epidemiology of alcohol related cirrhosis.

Methods

Among 1000 consecutive patients of cirrhosis, diagnosed by a combination of clinical, radiological and/or histopathological features, etiology was established by history of significant alcohol abuse, determining viral and autoimmune markers and by metabolic screening. Patients not confirmed to be cirrhotic were excluded from the study. All cases were studied to determine clinical features, complications, disease prognosis, and mortality. Alcoholic cirrhotics were then compared with nonalcohol etiology.

Results

72.2 % alcoholic cirrhosis were compared with 27.8 % patients of nonalcohol etiology and alcoholic cirrhotics were younger (45?+?9.4 years vs. 47.9?+?12.5 years), predominantly males (M/F ratio 37:1 vs. 1.8:1) with significantly high incidence of jaundice (38.5 % vs. 30.5 %), night blindness (14.4 % vs. 3.6 %), ascites (76.3 % vs. 69.1 %), upper gastrointestinal bleed (46.4 % vs. 34.5 %), and hepatic encephalopathy (24.1 % vs. 10.4 %). Biochemical parameters that were significantly higher in alcoholics were mean bilirubin (4.7?+?8.7 vs. 3.1?+?4.7 mg/dL), AST/ALT ratio (2.03 vs. 1.4), gamma-glutaryl transaminase levels (209.7?+?37.9 vs. 93.9?+?14 IU/mL), and serum ammonia (75.1?+?55.7 vs. 52.1?+?45.4 mg/dL). Mean model for end-stage liver disease, scores, and Child C disease was significantly higher in alcoholics (18.6?+?7.7 vs. 15.6?+?6.4) and (54.1 % vs. 37 %), respectively, representing advanced disease at presentation. Mortality within 1 month was significantly higher among alcoholic cirrhosis (9.8 % vs. 3.2 %).

Conclusion

Thus, alcoholic cirrhosis is of major concern in North East India as majority patients are in most productive age group and presented with advanced disease. Short-term mortality was high among alcoholic cirrhotics. Proper education and legislation are essential to mitigate the consequences of this disease.
  相似文献   
93.
This study aimed to evaluate the relationship between inflammatory biomarkers and endothelial dysfunction (ED), as measured by brachial artery flow-mediated dilation (FMD).

Methods:We conducted a cross-sectional analysis utilizing baseline data of 135 participants with HIV infection on stable antiretroviral therapy (ART) in the Hawaii Aging with HIV-Cardiovascular (HAHC-CVD) study who had available baseline inflammatory biomarkers and brachial artery FMD measurements.

Results:We observed significant associations between brachial artery FMD and baseline brachial artery diameter, age, male gender, traditional cardiovascular disease (CVD) risk factors such as BMI, waist to hip ratio, hypertension, systolic blood pressure (BP), diastolic BP, and LDL cholesterol, and 10-year coronary heart disease (CHD) risk estimated by Framingham risk score (FRS). Of all biomarkers tested, higher level of C-reactive protein (CRP) (beta?= ??0.695, P?=?0.030) and serum amyloid P (SAP) (beta?= ??1.318, P?=?0.021) were significantly associated with lower brachial artery FMD in univariable regression analysis. After adjusting for baseline brachial artery diameter, age, and selected traditional CVD risk factors in multivariable model, SAP remained significantly associated with brachial artery FMD (beta?= ??1.094, P?=?0.030), while CRP was not (beta?= ??0.391, P?=?0.181).

Discussion:Serum amyloid P was independently associated with impaired brachial artery FMD and may potentially relate to ED and increased CVD risk in HIV-infected patients on stable ART.  相似文献   
94.
95.

Context:

Hyponatremia is a common electrolyte disturbance in critically ill hence understanding its implications is important.

Aims:

This study was carried out to ascertain frequency, predisposing conditions and outcome in critically ill patients with hyponatremia on intensive care unit (ICU) admission.

Settings and Design:

This was an observational, prospective study of a series of ICU patients during a 12-month period.

Materials and Methods:

The patients were divided into two groups: Hyponatremic (serum sodium < 135 mmol/L) and Eunatremic groups (135-145 mmol/L). Clinical examination included volume status and drug history, biochemistries, clinical diagnosis and cause of hyponatremia.

Statistical Analysis Used:

Fisher''s exact test, unpaired t-tests Wilcoxon ranksum tests, profile-likelihood method, log-rank test and Kaplan—Meier curves were used. P < 0.05 were considered to be statistically significant.

Results:

In the hyponatremic group, the frequency of hyponatremia on ICU admission was 34.3%, most were euvolumic, 58.96%. Females comprised of 36.5%. The mean age was 60.4 ± 17.2. The Syndrome of inappropriate Antidiuretic Hormone (SIADH) criteria was met in ninety-one patients (36.25%), peumonia being the leading cause of SIADH. Patients with severe sepsis, elective surgery patients, renal failure and heart failure, cirrhosis of liver and subarachnoid hemorrhage were other more likely etiologic causes (P < 0.05). The hyponatremic group spent a longer time in the ICU (P = 0.02), had longer mechanical ventilator days (P < 0.05) and had an increased mortality rate (P = 0.01).

Conclusions:

Hyponatremia present on admission to the ICU is independent risk factors for poor prognosis.  相似文献   
96.

Background and Aims:

Tracheal tubes are commonly used in intensive care unit (ICU) and lead to complications like displacements. The primary aim of the study was to evaluate if the rate of tracheal tube displacement benchmarked at <1% per patient and <0.5% per tracheal tube day, could be sustained over a prolonged period. The secondary aim was to document the patterns of all forms airway accident and to evaluate their consequences.

Subjects and Methods:

This was a prospective observational study of Intubated and ventilated patients in a General Medical-Surgical Adult ICU. The incidence of accidental extubation, self extubation, partial displacement and blockages of tracheal tubes were recorded.

Results:

The overall tracheal tube displacement rate was 61/10,112 (0.6%) per patient and 61/28,464 (0.22%) per tracheal tube day. There were 30 additional incidents of blockage, kinking or biting of the tracheal tube. Physiological consequences-69 were mild, 10 moderate, 12 major and one death. Of the 91 accidents, 30 were partly and 30 were completely preventable. 76 incidents involved an endotracheal tube (54 displaced, 12 blocked and 10 bitten-kinked) and 15 a tracheostomy tube (seven displaced and eight blocked). Accidents were more common in medical than surgical patients (medical = 48, cardiac surgical = 17 and other surgical/trauma = 26).

Conclusion:

Tracheal tube displacement rate in a mixed medical-surgical adult ICU was maintained below the pre-set benchmark of <1% per patient and <0.5% per intubated day over nearly a decade.  相似文献   
97.
Visceral leishmaniasis affects millions of people worldwide in areas where Leishmania donovani is endemic. The protozoan species serves a greater threat as it has gradually evolved drug resistance whereby requiring newer approaches to treat the infection. State‐of‐art techniques are mostly directed toward finding better targets extracted from the available proteome data. In light of recent computational advancements, we ascertain and validate one such target, adenylosuccinate lyase (ADSL) by implementation of in‐silico methods which led to the identification of critical amino acid residues that affects its functional attributes. Our target selection was based on comprehensive topological analysis of a knowledge‐based protein–protein interaction network. Subsequently, mutations were incorporated and the dynamic behavior of mutated and native proteins was traced using MD simulations for a total time span of 600 ns. Comparative analysis of the native and mutated structures exhibited perceptible changes in the ligand‐bound catalytic region with respect to time. The unfavorable changes in the orientations of specific catalytic residues, His118 and His196, induced by generated mutations reduce the enzyme specificity. In summary, this integrative approach is able to select a target against pathogen, identify crucial residues, and challenge its functionality through the selected mutations.  相似文献   
98.
99.
Protein folding is described conceptually in terms of diffusion over a configurational free-energy landscape, typically reduced to a one-dimensional profile along a reaction coordinate. In principle, kinetic properties can be predicted directly from the landscape profile using Kramers theory for diffusive barrier crossing, including the folding rates and the transition time for crossing the barrier. Landscape theory has been widely applied to interpret the time scales for protein conformational dynamics, but protein folding rates and transition times have not been calculated directly from experimentally measured free-energy profiles. We characterized the energy landscape for native folding of the prion protein using force spectroscopy, measuring the change in extension of a single protein molecule at high resolution as it unfolded/refolded under tension. Key parameters describing the landscape profile were first recovered from the distributions of unfolding and refolding forces, allowing the diffusion constant for barrier crossing and the transition path time across the barrier to be calculated. The full landscape profile was then reconstructed from force-extension curves, revealing a double-well potential with an extended, partially unfolded transition state. The barrier height and position were consistent with the previous results. Finally, Kramers theory was used to predict the folding rates from the landscape profile, recovering the values observed experimentally both under tension and at zero force in ensemble experiments. These results demonstrate how advances in single-molecule theory and experiment are harnessing the power of landscape formalisms to describe quantitatively the mechanics of folding.  相似文献   
100.

PURPOSE

The objective of this study was to evaluate the effect of sociodemographic factors on quality of satisfaction towards denture treatment.

MATERIALS AND METHODS

One hundred subjects (filling inclusion criteria) who were wearing a denture for at least two months were enrolled and divided into five groups on the basis of sociodemographic variables (age, gender, literacy level, socio-economic and marital status). Questionnaires consisting of 38 questions (positive and negative attitude towards denture satisfaction) related to patients'' perception of clinical outcome in different domains such as mastication, appearance, speech, comfort, health, denture care and social status were scored by the subjects. Questions reflecting positive attitude were scored as 2, 1, or 0 (yes, uncertain and no, respectively) and reversely for the negative questions. Statistical analysis was done by using Statistical Package for Social Sciences (α = .05).

RESULTS

Level of denture satisfaction was higher in age subgroup belonging to 45 - 65 years of age in relation to comfort, health and denture care. Female and male showed significant priority for denture treatment because of esthetic and function respectively. Level of satisfaction was statistically significant with literacy level. Upper high income group showed significantly higher level of satisfaction only in case of social status. Married group showed significantly higher satisfaction level only with comfort.

CONCLUSION

Patients'' sociodemographic variables were influential factors on denture satisfaction.  相似文献   
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