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81.
T lymphocytes can be activated and induced to proliferate through stimulation of the CD2 glycoprotein with functional combinations of CD2 antibodies. However, this mechanism of signal transduction via CD2 is still not fully understood. We have investigated which molecules on the T cell surface preferentially associate in Cis with CD2 and may regulate its signaling properties. Though a quantification method we found that CD5 represents the antigen capable of co-precipitating a larger proportion of CD2. Using co-capping assays and immunoprecipitations from cell lysates, we show that an association between CD2 and CD5 can be found in rat thymocytes, T lymphocytes and in a thymoma cell line. Possibly, this interaction is a direct one, since CD2 and CD5 transiently expressed in Cos7 cells co-precipitate each other. Furthermore, using CD2 chimeric proteins containing different domains of CD2, expressed in Cos7 cells as well as in stably transfected Jurkat cells, we show that the interaction between CD2 and CD5 is held at both the intra- and extracellular levels, but does not involve the transmembrane domain. The fact that both the extracellular and the cytoplasmic domains of CD2 interact with CD5 suggests a specific and tight association between the two molecules, possibly relevant for the fine-tuning of signal transduction in T lymphocytes.  相似文献   
82.
Menisci have an important role in load bearing, shock absorption, knee joint stability, and joint lubrication. Meniscal lesions and meniscectomy are followed by osteoarthritis in a high percentage of patients. At present, there is no ideal prosthesis for meniscal substitution. In this work, a bioreabsorbable polymer scaffold made of poly(L-lactic acid) (PLLA) and poly(p-dioxanone) (PPD) blend was developed to be used as a temporary meniscal prosthesis to stimulate the formation of an in situ meniscal replication while the scaffold is reabsorbed by the organism. Total meniscectomy of medial meniscus and arthrotomy was made in both back knees of 34 adult New Zealand white rabbits by medial parapatellar incision. The scaffolds were sutured in one of the knees, and other was used as a control. A meniscal replica was developed, suggesting that this material has great potential to be used as a meniscal prosthesis, especially because the new meniscus promoted a significant protection of cartilage, and cartilage degeneration in the control condyles was observed.  相似文献   
83.
In this paper two patients with penetrating ulcers of the descending thoracic aorta are presented, a clinical condition recognized only recently, that may have a severe or even fatal outcome, due to rupture of the aorta. It is a peculiar form of the atherosclerotic disease, and its clinical and imagiologic presentation may mimics the classic aortic dissection of the distal type type. Computed tomography, nuclear magnetic resonance and transesophageal ecocardiography are the most apropriate methods for studying and diagnosis and the surgical management, aimed at the prevention or treatment of the aortic rupture, and based on the prosthetic aortic replacement, is the only alternative allowing the definite cure of the disease. The main features of pathology, clinical manifestations, diferential diagnosis and surgical management of this entity are described and discussed, according to the most recently articles published in the literature, on the subject.  相似文献   
84.
This study consisted of a bibliographical survey in the databases LILACS, MEDLINE and ILO-CIS BULLETIN - SAFETY AND HEALTH AT WORK, with a view to identifying the main agents that can favor contact with these risks and cause health alterations in nursing workers. 37 articles were found, only four of which were published in national journals. Articles reported on the detection of chemical risks in the manipulation of cytostatic drugs; in the exposure to anesthetic gases, formaldehyde/glutaraldehyde vapor and sterilizing gases, among others.  相似文献   
85.
OBJECTIVE: Currently, the risk of aneurysm sac rupture after endovascular abdominal aortic aneurysm repair (EVAR) is estimated by using a group of anatomic variables. Available techniques for pressure monitoring include either direct measurement using catheter-based techniques or indirect measurement requiring implantation of a pressure sensor during aneurysm repair. None of these methods is without limitations. Radiation pressure, such as that generated by a modulated ultrasound (US) beam, can induce surface vibration at a distance. The velocity of the resulting surface waves depends on the tensile stress of the vibrated surface. By measuring the change in wave velocity, it is possible to detect the change in tensile stress and calculate the pressure through the vibrated surface. We tested this concept in an in vitro aneurysm model. METHODS: Rubber tubes and explanted porcine abdominal aortas were used to model an aneurysm sac. The surface of the model was vibrated with an amplitude-modulated US beam. The resulting motion was detected either by reflected laser light or by Doppler US. The phase of the propagating wave was measured to assess changes in velocity with different pressures. RESULTS: Increasing hydrostatic pressure in the rubber model correlated well with the cumulative phase shift (R(2) = 0.96-0.99; P < .0001). By using a pump to generate dynamic pressure (between 110 and 200 mm Hg), the cumulative phase shift correlated well with the square of the mean pressure (R(2) = 0.92; P < .0001); however, the correlation with pulse pressure was poor (24-36 mm Hg; r = 0.38; P < .02). In the porcine in vitro aortic sac model, the cumulative phase shift detected with both laser (r = 0.94-0.99; P < .0001) and Doppler (r = 0.96-0.99; P < .0001) correlated well with the aneurysm pressure. CONCLUSIONS: Application of vibrometry for noninvasive measurement of aortic aneurysm sac tension is feasible in an in vitro setting. The concept of vibrometry may be used to detect endotension noninvasively after EVAR. Vibrometry may also be used to estimate wall stress in native aneurysms, and it may predict the risk of aneurysm rupture. CLINICAL RELEVANCE: Vibrometry may offer a technique for completely noninvasive monitoring of aneurysm sac pressure after EVAR. Vibrometry is based on the following principles: radiation pressure, such as that generated by modulated US, can induce surface vibration at a distance; by measuring the change in wave velocity of vibration, it is possible to detect changes in tensile stress and calculate the pressure through the vibrated surface. We tested this concept in an in vitro model and found that application of vibrometry for noninvasive measurement of aortic aneurysm sac tension is feasible. Vibrometry may also be used to estimate wall stress in native aneurysms.  相似文献   
86.
87.
Parameters of diastolic function have been shown to correlate with exercise capacity (EC) in individuals with impaired left ventricular (LV) systolic function. However, the role of LV diastolic function in predicting EC in Chagas cardiomyopathy has not been reported. Objectives: This study aimed to determine the relationship between LV diastolic parameters assessed by echocardiography and EC in patients with Chagas cardiomyopathy. Methods: We studied 40 patients (23 men; 49 ± 8 years), with diagnosis of Chagas disease and dilated cardiomyopathy. Medical therapy was individually adjusted according to standardized guidelines. Methods of acquiring two‐dimensional Doppler, tissue Doppler imaging (TDI), and their measurements were described. Exercise testing was performed by a Bruce protocol. Brain natriuretic peptide (BNP) levels were also determined. Results: Most patients (63%) were in NYHA functional class I. Mean peak oxygen consumption estimated (peakVO2) was 31.7 ± 10.2 mL/kg per minute, and mean left ventricular ejection fraction (LVEF) was 36.3 ± 7.8%. Univariate analysis showed that various echocardiographic parameters of diastolic function were correlated with peakVO2. There was no correlation between BNP levels or LVEF and EC. Multivariate analysis, after adjustment for age and gender, revealed that E/E′ ratio and left atrial volume (LAV), emerged as independent predictors of EC, as demonstrated in the model: peakVO2= 60.825 + (0.439 × LAV) ? (1.620 × E/E′ ratio) ? (0.483 × age) ? (4.821 × female gender). The R2 of this model was 0.52. Conclusions: Functional capacity assessed by peakVO2 was related to increase LV filling pressures, independently on systolic function in patients with Chagas cardiomyopathy. (Echocardiography 2010;27:519‐524)  相似文献   
88.
Piperazine designer drugs are a group of synthetic drugs of abuse that have appeared on the illicit market since the second half of the 1990s. The most common derivatives are 1-benzylpiperazine (BZP), 1-(4-methoxyphenyl)piperazine (MeOPP) and 1-(3,4-methylenedioxybenzyl)piperazine (MDBP). They can be consumed as capsules, tablets, but also in powder or liquid forms. Generally, although less potent than amphetamines, piperazines have dopaminergic and serotonergic activities. The aim of this work was to evaluate the toxic effects of BZP, MeOPP and MDBP using Caenorhabditis elegans as in vivo model for acute toxicity, development, reproduction and behavior testing. The LC50 for BZP, MeOPP and MDBP were 52.21, 5.72 and 1.22 mm , respectively. All concentrations induced a significant decrease in the body surface of the worms, indicating developmental alterations, and decrease in the brood size. Worms exposed to piperazine designer drugs also presented a decrease in locomotor activity and mechanical sensitivity, suggesting the possible dysfunction of the nervous system. Neuronal damage was confirmed through the decrease in fluorescence of BY200 strains, indicating loss of dopaminergic transporters. In conclusion, we suggest that piperazine designer drugs lead to neuronal damage, which might be the underlying cause of the altered behavior observed in humans.  相似文献   
89.

Purpose

Untreated dental caries is a persistent oral problem among preschool children. Although there is vast evidence regarding the impact of dental caries on oral health-related quality of life (OHRQoL) in this age group, evidence on the impact of untreated caries severity is scarce. The purpose of this study was to investigate the impact of untreated caries severity on the OHRQoL of preschool children and their families.

Methods

A cross-sectional study was conducted with 563 individuals in the city of Goiania, Brazil. Data were collected through interviews with parents/caregivers and clinical examinations of their children. The OHRQoL was measured by the Brazilian version of the Early Childhood Oral Health Impact Scale. Untreated dental caries severity was assessed using validated indices. Other independent variables were socioeconomic, toothache prevalence, and the questionnaire respondent. Statistical analysis involved bivariate comparisons and Poisson regression analyses.

Results

A higher prevalence of impact on OHRQoL was found among preschool children with untreated dental caries with clinical consequences (PR 1.31; 95% CI 1.01–1.70) compared to those without caries; those aged 5 years (PR 1.47; 95% CI 1.18–1.82), compared to those aged two; and those with a toothache (PR 1.54; 95% CI 1.34–1.76), compared to those without toothache. Moreover, fathers (PR 0.71; 95% CI 0.55–0.92) and other respondents (PR 0.70; 95% CI 0.52–0.96) perceived less impact on the OHRQoL in comparison to mothers.

Conclusions

Severe untreated dental caries with clinical consequences had a negative impact on the children’s OHRQoL, regardless of toothache and socioeconomic factors.
  相似文献   
90.
Few studies describe drug utilization in pregnancy focusing on prescribing practices. This study is part of a larger survey on perinatal care in the City of Rio de Janeiro, Brazil. The type of hospital (public, contracted out by the Unified National Health System, or private) determined the stratification of 10,072 hospitalized post-partum women, who were asked about medication used during pregnancy. Hospital records supplied information on drugs prescribed during labor. Drugs were classified according to the Anatomical Therapeutic Chemical (ATC) system. Another system was used for specific cases of referred use. A mean of 2.08 drugs was prescribed during labor, and a mean of 2.3 was reported during pregnancy. Anesthetics, antibiotics, oxytocin, and analgesics were the most frequently prescribed during labor, with significant differences between strata. Ferrous sulfate, vitamins, scopolamine, and acetaminophen were the main drugs reported during pregnancy. Women who had attempted abortion referred use of various kinds of tea (49.7%) and misoprostol (9.2%). The drug utilization pattern was consistent with the literature. This study offers knowledge on prescribing patterns during labor and self-reported use during pregnancy in both the public and private sectors.  相似文献   
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