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61.
Access to food and the amount consumed were investigated within a group of 45 children aged 33 to 60 months, among whom growth stunting was common. Children were observed throughout 1 day; all foods offered and consumed were weighed, and food-related behaviors noted. Children ate frequently, at least 2 meals and an average of 7.4 +/- 2.6 snacks daily. Children had access to 2029 +/- 575 kcal (8493 +/- 2407 kJ) yet only consumed 1528 +/- 343 kcal (6396 +/- 1436 kJ) daily; thus food availability was not restricting intake. A higher proportion of snacks than meals (85 per cent vs. 71 per cent) was consumed. Children requested foods frequently (x = 9.2 +/- 4.3) and 76 per cent of requests were fulfilled. Neither amount of accessible food nor amount consumed differed by age, gender, or socioeconomic status. The importance of the child's role in determining food intake, and of snacking to overall food consumption, was demonstrated.  相似文献   
62.
In every Radiation Oncology Department there is a group of patients referred for curative radiotherapy and within this group of patients there is a subset of patients who present the most difficult of treatment scenarios, maximum tumor dose and minimum spinal cord dose. The case to be presented involved the use of a head and neck five field technique of which three fields were treated isocentrically with the remaining two fields being electron boosts. It is from these patients that we extend to the maximum our planning capabilities.  相似文献   
63.
Atrophy of salivary glands may occur by ductal obstruction caused by calculus, infection or neoplastic processes, or as consequence of systemic diseases and aging. In the present work, we have used histochemical methods to study the expression of elastic and collagen fibers during experimental atrophy of the submandibular gland of mice. Glandular atrophy was accompanied by a rapid increase in collagen deposition in both septal and intralobular regions. The expression of elastic fibers was not significantly altered during atrophy; a discrete increase of elastic fibers was noted only around ductal structures. The results showed that experimental ductal obstruction is a useful in vivo model to study molecular events that take part in the remodeling of the extracellular matrix during atrophy of salivary glands.  相似文献   
64.
To define the underlying mechanism of neuromuscular transmission failure induced by anticholinesterases, we simultaneously performed surface recordings of compound muscle action potentials (CMAPs) and intracellular recordings of miniature end-plate potentials (MEPPs), miniature end-plate current (MEPCs), and end-plate potential (EPPs) in rat diaphragms exposed in vitro to 1 × 10?4 to 2 × 10?2 mmol/L neostigmine methylsulfate. At low concentrations of neostigmine, repetitive stimulation of the phrenic nerve resulted in decrement followed by complete recuperation of CMAP amplitudes. This bimodal pattern was associated with maximal end-plate depolarization at the beginning of the stimulation period, increased MEPP amplitudes, and prolonged time constants of MEPC decays. Higher concentrations of neostigmine resulted in a unimodal decline of amplitudes of CMAPs and EPPS, reduced MEPP amplitudes, and a double exponential time course of MEPC decays. These results indicate that low concentrations of anticholinesterases impaired neuromuscular transmission by producing transient depolarization of the end-plate region. Higher concentrations induced desensitization and direct blockade of the end-plate receptor channel, probably in its open conformation. © 1993 John Wiley & Soncs, Inc.  相似文献   
65.
The present study provides an analysis of the effects of particular patterns of teacher respose to students' entries in dialogue journals. It extended on previous research related to teacher-student instructional discourse by concentrating on written, teacher-student interactions. Second grade children who were participating in a daily dialogue journal activity were randomly subjected to two types of response patterns by their teacher. The results show that a teacher's elaborative responses to student journal entries directly lead to increase written output by students coupled with a distinct process #ophigher order#cp orientation of student entries.  相似文献   
66.
Ciclesonide is an onsite-activated inhaled corticosteroid (ICS) for the treatment of asthma. This study compared the efficacy, safety and effect on quality of life (QOL) of ciclesonide 160 microg (ex-actuator; nominal dose 200 microg) vs. budesonide 400 microg (nominal dose) in children with asthma. Six hundred and twenty-one children (aged 6-11 yr) with asthma were randomized to receive ciclesonide 160 microg (ex-actuator) once daily (via hydrofluoroalkane metered-dose inhaler and AeroChamber Plus spacer) or budesonide 400 microg once daily (via Turbohaler) both given in the evening for 12 wk. The primary efficacy end-point was change in forced expiratory volume in 1 s (FEV1). Additional measurements included change in daily peak expiratory flow (PEF), change in asthma symptom score sum, change in use of rescue medication, paediatric and caregiver asthma QOL questionnaire [PAQLQ(S) and PACQLQ, respectively] scores, change in body height assessed by stadiometry, change in 24-h urinary cortisol adjusted for creatinine and adverse events. Both ciclesonide and budesonide increased FEV1, morning PEF and PAQLQ(S) and PACQLQ scores, and improved asthma symptom score sums and the need for rescue medication after 12 wk vs. baseline. The non-inferiority of ciclesonide vs. budesonide was demonstrated for the change in FEV1 (95% confidence interval: -75, 10 ml, p = 0.0009, one-sided non-inferiority, per-protocol). In addition, ciclesonide and budesonide showed similar efficacy in improving asthma symptoms, morning PEF, use of rescue medication and QOL. Ciclesonide was superior to budesonide with regard to increases in body height (p = 0.003, two-sided). The effect on the hypothalamic-pituitary-adrenal axis was significantly different in favor of ciclesonide treatment (p < 0.001, one-sided). Both ciclesonide and budesonide were well tolerated. Ciclesonide 160 microg once daily and budesonide 400 microg once daily were effective in children with asthma. In addition, in children treated with ciclesonide there was significantly less reduction in body height and suppression of 24-h urinary cortisol excretion compared with children treated with budesonide after 12 wk.  相似文献   
67.
68.
Effectiveness of montelukast in the treatment of cough variant asthma.   总被引:7,自引:0,他引:7  
BACKGROUND: Antileukotriene agents have been shown to be beneficial in chronic asthma. Although patients with cough variant asthma have cough with minimal wheezing and dyspnea, airway hyperresponsiveness from chronic inflammation is believed to be the underlying mechanism. OBJECTIVE: To evaluate the effectiveness of montelukast, a leukotriene receptor antagonist, in the treatment of cough variant asthma. METHODS: Fourteen patients with cough variant asthma participated in a randomized, double-blind, placebo-controlled trial with a 7- to 10-day baseline period and a 4-week treatment period with montelukast, 10 mg, or placebo daily. Inclusion criteria were (1) chronic cough with a duration of at least 4 weeks with minimal or no wheezing or dyspnea and (2) forced expiratory volume in 1 second of 50% to 85% of predicted and reversibility of 12% with use of an inhaled beta-agonist or forced expiratory volume in 1 second greater than 85% and positive methacholine challenge results. Patients fulfilled the minimum criteria for cough frequency and symptom scores for randomization. RESULTS: Eight patients received montelukast and 6 received placebo. The primary efficacy variable, mean percentage change from baseline in cough frequency, was significantly improved by the second week, and by the fourth week the mean percentage change from baseline was 75.7% for the treatment group and 20.7% for the placebo group. CONCLUSIONS: The leukotriene receptor antagonist montelukast seems to be effective in the treatment of cough variant asthma. Larger studies are recommended to confirm this effect.  相似文献   
69.
Since the syndrome of primary hyperaldosteronism was described by Jerome Conn in 1955, over 300 patients with this disorder have been identified in the medical centers of Vanderbilt University and the University of Michigan. The most frequent cause of this endocrinopathy has been a solitary adenoma of the adrenal cortex (72%); bilateral adrenocortical hyperplasia has been the cause of primary hyperaldosteronism in 27% of cases; less frequently, the cause has been multiple and/or bilateral adenomas (1%). During the last 4 years in these 2 medical centers, we have encountered 3 patients who have had biochemically proven primary hyperaldosteronism due to adrenocortical carcinoma. Each of these unusual cases is summarized with review of the recent literature.
Resumen Desde la descripción del síndrome de hiperaldosteronismo primario por Jeremo Conn en 1955, más de 300 pacientes con esta entidad han sido identificados en nuestros 2 centros médicos, la Universidad de Vanderbilt (Nashville) y la Universidad de Michigan (Ann Arbor). La causa más frecuente de esta endocrinopatía ha sido el adenoma solitario de la corteza suprarrenal (72%); la hiperplasia adrenocortical bilateral ha sido la causa del hiperaldosteronismo primario en 27% de los casos; con menor frecuencia se han presentado los adenomas multiples y/o bilaterales (1%). En los 4 últimos años hemos encontrado 3 pacientes con hiperaldosteronismo primario comprobado bioquímicamente producido por carcinoma adrenocortical. Se presenta cada uno de estos casos poco usuales junto con una revisión de la literatura reciente.

Résumé Depuis que le syndrome d'hyperaldostéronisme primitif a été décrit par Jerôme Conn en 1955 plus de 300 sujets qui en étaient victimes ont été identifiés à la Vanderbilt University de Nashville et à l'University of Michigan de Ann Arbor. La cause la plus fréquente de cette endocrinopathie répond à un adénome solitaire de la cortico-surrénale (72%) alors que l'hyperplasie corticale des 2 surrénales est plus rarement à son origine (27%), les adénomes multiples et/ou bilatéraux étant rarissimes (1%). Au cours des 4 dernières années 3 cas d'hyperaldosteronisme dû à un cancer de la cortico-surrénale ont été observés dans les 2 centres. Chacun de ces cas exceptionnels est exposé cependant que la littérature récente concernant l'hyperalderosteronisme est analysée.


Presented at the International Association of Endocrine Surgeons in Paris, September 1985.  相似文献   
70.
Current evidence indicates that signal transduction after receptor binding of PTH involves the stimulation of adenylate cyclase as well as stimulation of phosphoinositide metabolism. Recent studies, showing that PTH alters phosphate transport in opossum kidney cells at concentrations which do not increase cAMP production and that activators of protein kinase-C also alter phosphate transport, have led to the suggestion that there is a dual mechanism for the regulation of phosphate transport by PTH, namely, protein kinase-C at physiological levels of PTH and cAMP at higher levels of PTH. The present studies were designed to evaluate the relationship between cAMP-dependent protein kinase (PK-A), a more sensitive indicator of alterations in cAMP metabolism than measurements of total cellular cAMP, and phosphate transport in opossum kidney cells, in response to bovine (b)PTH 1-34 and [Nle8,Nle18,Tyr34]bPTH 3-34 amide. While bPTH 1-34 markedly stimulated cAMP accumulation (half-maximal stimulation between 1 and 10 nM), PTH 3-34 analog did not. Phosphate transport was inhibited in a dose-dependent manner by bPTH 1-34, with half-maximal effect occurring between 0.1 and 1 nM. [Nle8,Nle18,Tyr34]bPTH 3-34 amide also altered phosphate transport, although this peptide was 3 orders of magnitude less potent than bPTH 1-34. PK-A activity increased in response to bPTH 1-34 and correlated closely with the effects of PTH on phosphate transport. [Nle8,Nle18,Tyr34]bPTH 3-34 amide, which did not appear to increase cAMP, also resulted in a significant increase in the activity of PK-A. Studies of inhibition of cAMP accumulation using 2',5'-dideoxyadenosine demonstrated that while this agent markedly inhibited the accumulation of cAMP in response to PTH, the effects of PTH on phosphate transport were not altered. However, in spite of the reduction in cAMP the activation of PK-A was similar to control. These data indicate that the effects of PTH peptides on phosphate transport are more closely related to changes in the activity of PK-A than to levels of total cAMP. Activation of PK-A in response to PTH is demonstrable at the lowest doses of PTH that alter phosphate transport.  相似文献   
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