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51.
Abstract  Preference utilitarians are concerned to maximize the autonomous choices of individuals; for this reason, they argue that nurses ought to advocate for those patients who desire assistance with ending their lives. This approach prompts us to consider, then, the moral validity of nursing involvement in measures intended to end the lives of patients. In this article, the terms of preference utilitarianism are set out and considered in order to determine whether this approach offers sufficient philosophical support for sanctioning a role for nursing in euthanasia. Ultimately, it is found that preference utilitarianism is lacking in this respect, as well as in its fitness for guiding nursing activity in general. In particular, it is found that nurses are required to exchange a handmaiden relationship with the medical profession for an equally undignified relationship with patients. If nursing involvement in measures intended to end the lives of patients is to find sufficient philosophical support, then we need to look elsewhere.  相似文献   
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The release of newly synthesized 3H-dopamine (3H-DA) was measured in the rat striatum superfused, through a push-pull cannula, with a physiological medium enriched in 3H-tyrosine. The level of spontaneous 3H-DA release was dependent on the topographical localisation of the cannula in the striatum (anterior parts displayed higher levels than posterior ones) and on the anesthetic state (halothane anesthetized rats demonstrated higher levels than awake ones). Inhibition of DA inactivation processes by local application of benztropine (a DA reuptake inhibitor, 10−6 M) or by IV administration of pargyline (a MAO inhibitor, 100 mg/kg) enhanced the detectable outflow of 3H-DA from the striatum in both halothane anesthetized and awake rats. Local application of D-amphetamine (10−5 M) or acetylcholine (5 × 10−5 M) in the presence of eserine (5 × 10−5 M) evoked respectively a fivefold and a 30% increase in spontaneous 3H-DA release in halothane anesthetized rats. Inhibition of the firing of dopaminergic neurons by IV injection of gamma-hydroxybutyrate (400 mg/kg) produced a 30% decrease in striatal 3H-DA release. The present results demonstrate that the push-pull cannula method is suitable for the study of DA release in both the anesthetized and the awake rat.  相似文献   
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Background: Smoking is considered to be a risk factor for patients undergoing surgery and anesthesia, but it is unclear whether this is applicable to patients undergoing ambulatory surgery. The aim of this study was to determine the risk of respiratory complications and wound infection among smokers.

Methods: The authors studied a random selection of 489 adult patients undergoing ambulatory surgery. Smoking status was determined by self-report and confirmed with end-expired carbon monoxide analysis. The risk of respiratory complications (i.e., desaturation, cough, laryngospasm, bronchospasm, breath-holding, or apnea) and wound infection (i.e., wound redness or discharge +/- positive microbial culture, requiring antibiotic therapy) in smokers versus nonsmokers was ascertained. Odds ratios were estimated from multivariable logistic regression and adjusted for age, gender, body mass index, partner's smoking status, domiciliary smoking exposure, and extent and duration of surgery.

Results: Most smokers continued to smoke up until the day of surgery. Smokers had a higher rate of respiratory complications (32.8%vs. 25.9%; adjusted odds ratio, 1.71; 95% confidence interval, 1.03-2.84;P = 0.038) and wound infection (3.6%vs. 0.6%; odds ratio, 16.3; 95% confidence interval, 1.58-175;P = 0.019). Odds ratios comparing current plus ex-smokers with nonsmokers were of similar magnitude for most of these complications.  相似文献   

55.
Journal of Prevention - The major issues involved in the design and implementation of effective school screening programs are addressed, using data from a longitudinal study following over 500...  相似文献   
56.
BACKGROUND: Until recently, there has been no practical alternative to the use of calcineurin inhibitors (CIs) as primary immunosuppressants in lung transplantation (LTx) and heart transplantation (HTx). Sirolimus (SRL) is a novel powerful immunosuppressant without renal toxicity, a common post-transplant problem associated with CI therapy. METHODS: SRL was used in 20 LTx and 5 HTx recipients >90 days post-transplant, where serious renal impairment was limiting CI dosing. Patients started on 2 to 5 mg/day orally at a median of 1,185 days post-transplant. Dosage adjustments were made according to trough levels, toxicity and perceived efficacy. With SRL initiation, 48% ceased CI therapy and the remainder decreased their dose substantively. RESULTS: After 30 days, 4 of 5 dialyzed patients ceased dialysis and 15 of 20 patients with an elevated serum creatinine (Cr) (mean Cr 0.29 mmol/liter) improved their Cr. The direction of change in Cr at 30 days predicted longer term Cr. The starting Cr did not predict the 30-day or long-term value. There were two bouts of acute and one bout of chronic rejection. There were 35 infectious complications in 16 patients and 24 episodes of potential SRL-related toxicity in 17 patients. These events generally responded to dose reduction or temporary cessation and were level-related. Fifteen recipients presently remain on the drug. None of the 7 deaths could be directly related to toxicity. CONCLUSION: SRL is a useful alternative immunosuppressant, allowing significant CI withdrawal in transplant recipients with renal impairment. Whether the resulting improvement in Cr can be maintained in the long term probably depends on the balance between the extent of acute and chronic renal damage.  相似文献   
57.
Pseudomosaicism for trisomy 2 is a relatively common finding at amniocentesis. However, genuine trisomy 2 mosaicism is extremely rare. As a result, very few cases have been described and little information is available with which to counsel the parents of an affected fetus. We describe a case of mosaic trisomy 2 diagnosed at amniocentesis in a fetus with multiple anomalies on ultrasound scan. Following termination of pregnancy, the fetus was found to have mild dysmorphic features, together with an absent gall bladder, cystic left kidney, a 13th left rib and mild unilateral talipes. The presence of trisomy 2 cells was confirmed by both standard cytogenetic analysis and fluorescent in-situ hybridisation techniques in multiple fetal tissues, as well as in the cord and placenta.  相似文献   
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BACKGROUND & AIMS: To compare the efficacy of controlled-release budesonide capsules with that of mesalamine for maintaining remission and improving quality of life (QOL) in patients with steroid-dependent Crohn's disease. METHODS: Fifty-seven patients (25 men; mean age, 32 +/- 10.1 yr) with quiescent steroid-dependent Crohn's ileitis, ileocolitis, or colitis (Crohn's disease activity index <150) entered a prospective, investigator-blind trial. Patients were eligible for treatment with azathioprine but had not consented or had developed side effects. Patients were randomized to receive budesonide 6 mg/day (n = 29) or mesalamine 1 g 3 times/day (n = 28). Follow-up assessments were made every 2 months for up to 1 year or until relapse. At each visit, quality of life (QOL) was assessed using the Inflammatory Bowel Disease Questionnaire (IBDQ). RESULTS: There were no significant differences in baseline clinical characteristics between the study groups. The 1-year relapse rate was significantly lower in the budesonide group than in the mesalamine group (55% vs. 82%; 95% confidence interval, 12.4%-41%; P = 0.045). Patients assigned to budesonide also remained in remission longer (241 +/- 114 days vs. 147 +/- 117 days; 95% confidence interval, 32.7-155.3 days; P = 0.003). Compared with mesalamine, budesonide treatment also was associated with a better QOL throughout the study (mean total IBDQ scores 165 +/- 36 vs. 182 +/- 28, respectively; 95% confidence interval, -0.4 to 34.4, P = 0.0001). This advantage was confirmed in patients' self-assessed QOL scores. CONCLUSIONS: Over a 1-year period, controlled-release budesonide was significantly more effective than mesalamine for maintaining remission and improving the QOL of patients with steroid-dependent Crohn's disease.  相似文献   
59.
Several clinical and pathologic factors appear to affect melanoma recurrence and survival. While much attention has been directed at identifying prognostic factors, few researchers have developed predictive models for survival and recurrence. Two major clinical questions are of interest in the management of melanoma: 1) what is the patient's chance of surviving for a given period, e.g., 5 or 10 years, after diagnosis of melanoma; and 2) after a patient has been disease free for a period of time, e.g., 5 years, what is his or her chance of melanoma recurrence or death in the following interval, e.g., 5 years or 10 years. In this paper, a generalized multivariate prognostic model to address both of these clinical questions is presented.Tables of the estimated probabilities of melanoma recurrence and death for prognostic subgroups are shown to facilitate prediction of an individual patient's outcome. The model was based on a database of 4,568 patients with localized melanoma, one of the largest melanoma databases in the world with detailed clinical and pathologic information, and long-term follow-up. Tumor thickness at diagnosis was the single most important prognostic factor for all outcomes. Tumor ulceration, Clark's level, lesion location, and sex had an impact on overall survival from diagnosis for some of the subgroups defined by tumor thickness. Tumor thickness at diagnosis was strongly indicative of melanoma recurrence and death even after a disease free interval of 2, 5, or 10 years. Lesion location and ulceration were of prognostic importance after disease free intervals up to 5 years, but their impact on melanoma recurrence and death diminished after longer disease free intervals.Prediction models for melanoma outcome at diagnosis and after a disease free period can provide useful information to clinicians in the management of melanoma patients. Utilization of the model will be valuable in identifying patients at high risk for melanoma recurrence and death.
Resumen Diversos factores clínicos y patológicos parecen afectar las tasas de recurrencia y mortalidad del melanoma. En tanto que se ha dispensado bastante atención en cuanto a identificar factores de pronóstico, pocos investigadores han desarrollado modelos de predicción de sobrevida y de recurrencia. Dos interrogantes principales son de interés en cuanto al manejo del melanoma: 1) cual es la probabilidad del paciente de sobrevivir un determinado período, por ejemplo 5 o 10 años, después del diagnóstico de melanoma; y 2) después de que el paciente se ha mantenido libre de enfermedad por un período de tiempo, por ejemplo 5 años, cual es su probabilidad de recurrencia del melanoma o de muerte en el siguiente período de tiempo, por ejemplo 5 o 10 años. En este artículo se presenta un modelo generalizado y multivariable de pronóstico para enfrentar estos interrogantes clínicos.Se presentan tablas para estimar las probabilidades de recurrencia y de muerte en divesos subgrupos de pronóstico que facilitan la predicción del destino final de un individuo. El modelo se fundamentó en una base de datos de 4568 pacientes con melanomas localizado, una de las más grandes bases de datos de melanoma existentes en el mundo, con detallada información clínica y patológica y con seguimiento a largo plazo. El espesor del tumor en el momento del diagnóstico apareció como el factor individual de pronóstico de mayor importancia. La ulceración del tumor, el nivel de Clark, la ubicación de la lesión y el sexo exhibieron importancia en cuanto a la sobrevida para algunos de los subgrupos definidos según el espesor del tumor. El espesor del tumor en el momento del diagnóstico fue un factor fuertemente indicativo de recurrencia y de muerte, aún después de un intervalo libre de enfermedad de 2, 5 o 10 años. La ubicación de la lesión y la ulceración aparecieron como de importancia en cuanto el pronóstico después de intervalos libres de enfermedad hasta de 5 años, pero tal importancia disminuyó después de intervalos libres de enfermedad de mayor duración.Los modelos de predicción del resultado final en el melanoma aplicados en el momento del diagnóstico y después de un período libre de enfermedad pueden proveer información útil para el manejo clínico de pacientes con melanomas. La utilización del modelo es de valor en la identificación de pacientes con mayor riesgo de recurrencia y muerte por melanoma.

Résumé Plusieurs facteurs cliniques et anatomopathologiques semblent déterminer la récidive et la survie des mélanomes. De nombreux auteurs se sont intéressés à l'identidification des facteurs de pronostic, mais peu d'équipes ont essayé d'élaborer un modèle permettant de prédire survie et récidive. Deux problèmes restent à résoudre dans le traitement des mélanomes: 1) quelles sont les chances de survie après le diagnostic de mélanome pour un patient donné, pendant une période donnée, par exemple 5 à 10 ans et 2) quels sont les risques de récidive ou de décès dans les 5 à 10 ans qui suivent une période donnée (par exemple 5 ans) où un patient semblait en rémission. Dans cet article, nous avons créé un modèle d'évaluation pronostique multifactorielle pour tenter de répondre à ces 2 questions.Des tables montrant les probabilités de récidive et de décès par mélanome, calculées à partir de sous groupes différents, peuvent aider à déterminer le pronostic. Ce modèle repose sur une banque de données de 4568 patients atteints de mélanome non disséminé. Il s'agit d'une des plus grandes banques de données au monde contenant des informations cliniques, anatomopathologiques et sur l'évolution à long terme. L'épaisseur de la tumeur au moment du diagnostic était le facteur pronostic le plus important pour déterminer l'évolution. Le caractère ulcéré, le stade de Clark, la localisation de la lésion et le sexe avaient tous une importance pronostique, influant sur la survie globale liée à l'épaisseur de la tumeur. L'importance de l'épaisseur de la tumeur au moment du diagnostic était un facteur de récidive et mortalité même après un intervalle long de 2, 5 ou 10 ans. Le site de la tumeur et son caractère ulcéré étaient également des facteurs associés à un risque de récidive tumorale ou de décès après une rémission de 5 ans. L'influence de ces facteurs diminuait en cas de rémission plus prolongée.Les modèles permettant d'évaluer l'évolution du mélanome malin au moment du diagnostic et apreès un intervalle de rémission sont utiles au cours du traitement du mélanome. Ils doivent permettre d'identifier les patients à risque de récidive et de décès.
  相似文献   
60.
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