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101.
We conducted an observational cohort study in three nurse-midwifery services to identify patient characteristics and clinical care measures related to perineal trauma at birth. Data were collected on all women who began care with a nurse-midwife in labor, using an adaptation of the Nurse-Midwifery Clinical Data Set (n = 3,049). Study variables included demographics, perineal management techniques and position for birth, and other intrapartum care and events. Univariate and multivariate analyses showed that episiotomy was strongly related to fetal bradycardia, prolonged second stage, ethnic status, and maternal education level. Warm compresses and flexion/counterpressure to slow delivery were protective. Spontaneous lacerations were influenced by these factors as well. The lateral position for birth was protective, and use of oils or lubricants and the lithotomy position increased lacerations. Multisite studies in nurse-midwifery practices may provide an ideal means of determining effective care measures in healthy populations.  相似文献   
102.
Introduction: Suramin is a synthetic polysulfonated naphthylurea which has been used for the treatment of African trypanosomiasis and onchocerciasis, but since the mid-1980s has received attention as a possible antiretroviral and antineoplastic agent. Objective: This clinical trial of suramin was undertaken as a phase I/II study in patients with hormone-refractory prostate cancer, with the hypothesis that the intensity of therapy with suramin could be increased significantly if measures were undertaken to maintain the plasma concentrations of the drug under 300 μg/ml. Methods: We report the clinical results of this trial, wherein patients were treated at three different targeted plasma suramin concentrations (275, 215 and 175 μg/ml) for varying periods of time (2, 4 or 8 weeks), with delivery of the drug by continuous intravenous infusion. Results: The major toxicity observed in this trial was neurologic, consisting of a motor and sensory peripheral neuropathy that resulted in both paresis and paralysis of the limbs. Nearly all of this severe (CTEP grade III, IV) neurologic toxicity was observed in the patients treated at a plasma suramin concentration of 275 μg/ml for 4 or more weeks. A single patient treated at 215 μg/ml for 8 weeks developed moderate (CTEP grade III) proximal lower extremity weakness, and no patient treated at 175 μg/ml developed this toxicity. The second most common toxicity observed was infection of the central venous catheter. The overall response rate for all of the evaluable patients was 17% (13 of 75 patients). In addition, prostate-specific antigen (PSA)-defined responses were observed in six patients receiving therapy at 175 μg/ml, but these responses were confounded by cessation of therapy with flutamide during suramin treatment. Conclusions: In summary, although plasma suramin concentrations were maintained below 300 μg/ml, neurologic toxicity nonetheless occurred with high frequency in patients treated at 275 μg/ml for 4 or more weeks. Therapy at 215 and 175 μg/ml was in general well tolerated, but central venous catheter-related infection, as well as the inconvenience and expense of continuous infusional therapy, make this method of drug delivery impractical. Only moderate antitumor activity was observed during this trial, but it is possible that both continuation of flutamide and flutamide withdrawal during suramin therapy confounded the assessment of suramin’s activity in hormone-refractory prostate cancer. Received: 9 June 1995/Accepted: 18 March 1996  相似文献   
103.
OBJECTIVE Autonomous cortisol secretion without clinical stigmata of Cushing's syndrome (CS) has been recently recognized and termed pre-clinical or sub-clinical CS. The common assumption is that CS is an extremely rare cause of uncontrolled diabetes; however, the prevalence of this entity has not been studied. We assessed the prevalence of pre-clinical CS among obese patients with uncontrolled diabetes. PATIENTS AND DESIGN (1) In a retrospective analysis, the medical records of 63 patients with endogenous CS were reviewed. (2) In a cross-sectional study, 90 obese patients (BMI >25 kg/m2) followed in a University Hospital and the local Health Fund endocrine and diabetes clinics, with poorly controlled diabetes (glycosylated haemoglobin >9%), underwent an overnight 1 mg dexamethasone suppression. In patients with non-suppressible cortisol levels (>140 nmol/l), Liddle's 2 and 8 mg dexamethasone suppression tests and imaging studies were performed. MEASUREMENTS The prevalence of poorly controlled diabetes, the major presenting symptom of CS, was assessed in the retrospective analysis. The prevalence of ‘true’ CS and the false positive rate in the overnight dexamethasone suppression test were calculated. The endocrine evaluation of the patients with pre-clinical CS and the effects of surgical cure on glycaemic control are described. RESULTS In the retrospective analysis, 11 (17.5%) had diabetes and 2 (3.2%) lacked the classic physical characteristics of the syndrome. In the cross-sectional study, 4 patients failed to suppress plasma cortisol (<140 nmol/l). In one patient the diagnosis of CS was not confirmed by a standard Liddle’s test and was therefore considered false positive. In the other 3, the diagnosis of CS was confirmed (prevalence of 3.3%, 95% confidence interval 1–9%). In all other patients the overnight cortisol suppression test was normal (cortisol level 47.3 ± 2.5 nmol/l (mean ± SEM)). After surgical treatment of CS, glycaemic control was markedly improved in all 5 patients (2 from retrospective and 3 from cross-sectional studies). CONCLUSIONS The prevalence of pre-clinical Cushing's syndrome in obese patients with poorly controlled diabetes appears to be considerably higher than previously believed. The overnight dexamethasone suppression test proved to be a simple, sensitive and highly specific screening test for Cushing's syndrome despite the presence of obesity and hyperglycaemia.  相似文献   
104.
The prevalence of Chlamydia trachomatis, Mycoplasma pneumoniae, group A beta-hemolytic streptococcus, and other treatable organisms was studied in children with and without pharyngitis. Children aged 2 to 12 years were evaluated between November 1985 and April 1986 in three family practice offices in the Salt Lake City area. Chlamydia trachomatis was not detected in the pharynx of any of the children studied. Mycoplasma pneumoniae was cultured from 5 percent of the 242 children studied, group A beta-hemolytic streptococcus from 30 percent, non-group A beta-hemolytic streptococcus from 5 percent, Hemophilus influenzae from 4 percent, and Staphylococcus aureus from 14 percent. The symptoms reported were not statistically associated with any organism isolated, and clinical signs of pharyngitis were associated only with the presence of group A beta-hemolytic streptococcus. Based on these results, management of pharyngitis in children should continue to be based on the detection and treatment of group A beta-hemolytic streptococcus.  相似文献   
105.
A New York court recently struck down state Office of Mental Health regulations governing research involving subjects with impaired decisionmaking capacity. The court held that neither incapacitated adults nor minors could participate in any research protocol that contained a nontherapeutic element, irrespective of possible benefits to the subject or the importance of the knowledge to be gained. Although the decision rested on a technical point of law and dealt only with psychiatric research, the court's holding has significantly broader implications.  相似文献   
106.
The clinical research coordinator plays a crucial role in organizing a site's participation in the expanding arena of multicenter medical and pharmacologic clinical trials. This summary clarifies the role of the clinical research coordinator for inexperienced staff members assuming these responsibilities and outlines planning procedures leading to successful implementation. Emphasis is placed on establishing an interdependent relationship with the principal investigator, careful protocol assessment, team building, and staff feedback. Useful tools such as study manuals and physicians' study orders are described.  相似文献   
107.
108.
Summary We have completed a phase I and pharmacology study of liposomally-encapsulated daunorubicin (DaunoXome). Of 32 patients entered, 30 were evaluable. No toxicity was encountered at the initial doseescalation steps from 10 to 60 mg/m2. At 80 mg/m2, two patients manifested grade 2 neutropenia. At least grade 3 neutropenia occurred in all patients receiving 120 mg/m2. Alopecia and subjective intolerance were mild. Cardiotoxicity was not observed except for an episode of arrhythmia in a patient with lung cancer and prior radiation. Only one minor objective response was observed in this population of refractory solid tumors. Pharmacokinetics differed from those of the free drug with no detection of daunorubicinol. We recommend future phase II studies with a dose of 100 mg/m2 in previously treated and 120 mg/m2 of DaunoXome in previously untreated patients with solid tumors.EDW is supported in part by ACS award 92-14-1  相似文献   
109.
Rabbit inflamed synovial tissue grown in culture synthesizes a factor that induces collagenase synthesis in chondrocytes and in cartilage. Synthesis of this factor by the synovial tissue is inhibited by cycloheximide but not by indomethacin. The factor has an apparent molecular weight of 30,000, is stable to heat and to trypsin treatment but is inactivated by acid. Induction of collagenase synthesis in chondrocytes occurs after a lag period of 6 hours.  相似文献   
110.
We have carried out a systematic analysis of the protein composition of highly purified mammalian spliceosomes. We show that > 30 distinct proteins, including 20 previously unidentified components [designated spliceosome-associated proteins (SAPs)], are specifically associated with the spliceosome in a salt-resistant complex. In contrast to these spliceosome-specific proteins, we show that hnRNP proteins are not tightly associated with purified prespliceosome and spliceosome complexes. The splicing factor U2AF65, U1 snRNP-specific proteins, and several SAPs are present in the earliest prespliceosome complex (E). A set of 10 proteins is then added to the first ATP-dependent prespliceosome complex (A), and concomitantly, a significant decrease in the level of U2AF65 is observed. The fully assembled spliceosome is formed by the addition of 12 proteins in a reaction that requires ATP and both the 5' and 3' splice sites.  相似文献   
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