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21.
Orbital ossifying fibroma is an extremely rare condition, especially in adults. This rare tumor mostly develops at the medial wall of the orbit. We report a histopathologically confirmed ossifying fibroma involving the lateral orbital wall in an adult. This case suggests that orbital ossifying fibroma should be considered in the differential diagnosis of orbital bony lesions in adults and that unusual presentations may occur.  相似文献   
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BACKGROUND AND OBJECTIVE: Trachoma remains the leading cause of preventable corneal blindness. The outcome of penetrating keratoplasty (PK) in these patients is usually poor because of the extensive corneal vascularization, adnexal and ocular surface problems. We evaluated the long-term results of PK in patients with corneal scarring due to trachoma. PATIENTS AND METHODS: The fiels of 16 eyes of 13 patients who underwent PK due to late sequel of trachoma were reviewed. RESULTS: Preoperative visual acuity ranged from light perception to finger counting levels. Preoperatively, dry-eyes, meibomian gland dysfunction, trichiasis and cicatricial entropion were treated. Over a mean postoperative follow-up of 26.1 +/- 15.6 months (range of 14-61 months), eyes required redrafting due to graft rejection and failure, and corneal ulceration (12.5%). Fourteen eyes remained clear grafts (87.5%), and 13 eyes (81.3%) achieved 0.1 or better visual acuity. CONCLUSIONS: These results suggest that although patients with corneal scarring due to trachoma are at high risk, PK may be helpful for visual rehabilitation.  相似文献   
24.
Microbial keratitis following penetrating keratoplasty.   总被引:2,自引:0,他引:2  
PURPOSE: To investigate the prevalence of microbial keratitis, predisposing risk factors and treatment modalities in patients who developed keratitis following penetrating keratoplasty (PK). PATIENTS AND METHODS: The records of 285 patients who had undergone PK between January 1991 and December 1995 in a tertiary care center were reviewed. Patients who developed postoperative microbial keratitis were evaluated for predisposing risk factors, microbiological etiology, response to broad spectrum antibiotic therapy and subsequent PK. Patients were mainly treated with fortified topical antibiotics with or without repeat PK. RESULTS: Of the 285 patient records reviewed, microbial keratitis developed in 21 eyes of 21 patients (7.4%). Seventy-one percent of infections occurred within 6 months after grafting. Keratitis initially began from the donor-recipient border in 16 cases (76.2%) and were central or paracentral in 5 patients. Predisposing risk factors included loose or exposed suture (9), suture removal (1), persistent epithelial defect (3), graft failure (3), contact lens wear (1), Stevens-Johnson syndrome (1). Fifteen (71.4%) patients were culture-positive consisting of Streptococcus pneumoniae (7), Staphylococcus aureus (5), Pseudomonas aureginosa (2), and Hemophilus influenzae (1). Forty-three percent of patients were successfully treated with medical therapy only. Seven patients underwent second PK for visual rehabilitation and 4 for tectonic purposes. After medical and surgical therapy, graft clarity was achieved in 17 (81%) of patients. CONCLUSIONS: The microbial keratitis following PK is a major postoperative problem affecting the long term prognosis. Careful selection of patients, and preoperative and postoperative control of risk factors, may decrease the frequency of this complication. Several factors, including loose or exposed sutures, epithelial defects, ocular surface disorders, and graft failure, may predispose patients to develop microbial keratitis following PK.  相似文献   
25.
We compared the efficacy and safety of a remifentanil (0.25 microg x kg(-1) x min(-1)-based balanced anaesthetic technique with a bupivacaine-based regional anaesthetic technique in an open label, multicentre study in 271 ASA physical status 1 or 2 children aged 1-12 years. Subjects requiring major intra-abdominal, urological or orthopaedic surgery were randomly allocated to receive either intravenous remifentanil (group R; n = 185) or epidural bupivacaine (group B; n = 86) with isoflurane/nitrous oxide for their anaesthesia. The majority of children in both groups (85% in group R, 78% in group B) showed no defined response to skin incision, and although the mean increase in systolic blood pressure (+11 mm Hg) was significantly greater in group R than in group B, this change did not represent a serious haemodynamic disturbance. More children in group R (31%) required interventions to treat hypotension and/or bradycardia than those in group B (12%), but these were easily managed by administration of fluids or anticholinergic drugs. Adverse events, mainly nausea and/or vomiting, occurred in 45% of group R and 42% of group B (NS). The adverse event profile of remifentanil in this study was typical of a potent mu-opioid receptor agonist. Remifentanil was as effective as epidural or caudal block in providing analgesia and suppressing physiological responses to surgical stimuli in children aged between 1 and 12 years undergoing major abdominal, urological, or orthopaedic surgery under isoflurane/nitrous oxide anaesthesia.  相似文献   
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OBJECTIVES: To evaluate the effects of long-term patient triggered ventilation (PTV) using assist/control or synchronized intermittent mandatory ventilation (SIMV) in very-low-birth-weight infants with respiratory distress. METHODS: Ninety-seven very-low-birth-weight infants who had undergone synchronized ventilation for respiratory distress or insufficiency were assessed from January 1995 to December 2000. Death, oxygen support, pneumothorax development while ventilated, intracranial hemorrhage, necrotizing enterocolitis, periventricular leukomalacia, retinopathy of prematurity and duration of ventilation were noted as the mean outcome measures. RESULTS: The mean birth weight was 1139 +/- 268 g (range 450-1500 g) and the mean gestational age was 29.0 +/- 2.8 weeks (range 23-36 weeks). Eighty-four per cent of 97 infants survived. Antenatal steroids were administered to only 20% of mothers. Surfactant was administered to all of the 67% of infants with respiratory distress syndrome. The mean duration of ventilator support was 4.7 +/- 7.3 days (1-43 days) for survivors and 8.9 +/- 11 days (1-45 days) for infants who died. No respiratory paralysis was necessary in any case during ventilation and pneumothorax was diagnosed in only eight infants. Severe intracranial hemorrhage (grade > or = III) and periventricular leukomalacia developed in 15% and 12% of infants, respectively. Necrotizing enterocolitis (Bell's classification stage > or = 2) and retinopathy of prematurity were noted in two infants. Four infants had evidence of chronic lung disease. The rate of survival without major morbidity was 83.5%. CONCLUSION: Patient-triggered ventilation, initially PTV with Asist/Control and subsequently with SIMV in very-low-birth-weight infants with respiratory distress is feasible, but optimization of trigger and ventilator performance with respect to respiratory diagnosis is essential.  相似文献   
28.
The technical name for a surgical sponge left in the body of a patient is inadvertent “gossypiboma.” The word is derived from the Latin word Gossypium for cotton and from the Kiswahili word boma for “place of concealment.” These retained sponges were first seen as “textilomas,” but were renamed “gossypiboma” in 1978. The first case was reported by Wilson in 1884. These are rarely are retrieved in the literature, because of legal complications. A higher incidence of retained laparotomy sponges has been reported in association with gynecological procedures. We report a case of gossypiboma in the 38th week of pregnancy that imitated an ovary neoplasm.  相似文献   
29.
The mitogen-activated protein (MAP) kinase cascades regulate a variety of cellular activities, including cell growth, proliferation, and apoptosis, and are reported to play a role in the actions of antidepressant treatment. There are a number of different classes of protein phosphatases that could influence the MAP kinase cascade. One of these, the MAP kinase phosphatase (MKP) family, is known to play a key role in dephosphorylation of activated MAP kinase. In the present study, we analyzed the expression of the MKP1, MKP2, and MKP3 isoforms in rat brain after electroconvulsive seizure (ECS), considered the most effective treatment for depression. In situ hybridization analysis demonstrates that ECS differentially regulates the expression of the MKP isoforms. Expression of MKP1 mRNA is robustly increased by acute ECS in the major cell layers of the hippocampus, including the dentate gyrus granule cell layer and the CA1 and CA3 pyramidal cell layers. In contrast, MKP2 is induced mainly in the dentate gyrus and MKP3 is preferentially increased in the CA1 and CA3 cell layers. In the prefrontal cortex, all three MKP isoforms are upregulated by acute ECS administration. Chronic ECS resulted in a similar pattern of induction for each of the MKP subtypes, demonstrating that there is little or no desensitization of the response to repeated ECS. The induction of MKP expression serves as negative feedback control for the MAP kinase cascades. Upregulation of MKP expression could dampen the actions of ECS, indicating that blockade of the MKPs could enhance the actions of antidepressant treatment.  相似文献   
30.
PURPOSE: Erythropoietin, an oxygen-regulated glycoprotein hormone, is a hematopoietic cytokine that stimulates erythropoiesis by binding to its cellular receptor [erythropoietin receptor (EPOR)]. The recombinant form of human erythropoietin is used to prevent or treat anemia in cancer patients. However, in a recent randomized, placebo-controlled trial involving patients receiving curative radiotherapy for squamous cell carcinoma of the head and neck, erythropoietin treatment was associated with poorer locoregional progression-free survival. The purpose of our study was to determine whether EPOR and its ligand erythropoietin are expressed in primary head and neck cancer. We also investigated the hypothesis that erythropoietin expression in malignant cells may be associated with the presence of tumor hypoxia, an important factor involved in resistance to radiation treatment, tumor aggressiveness, and poor prognosis. EXPERIMENTAL DESIGN: Twenty-one patients received an i.v. infusion of the hypoxia marker pimonidazole hydrochloride before multiple tumor biopsies. Contiguous sections from 74 biopsies were analyzed by immunohistochemistry for EPOR and erythropoietin expression and pimonidazole binding. RESULTS: EPOR expression was present in tumor cells in 97% of the biopsies. Coexpression of erythropoietin was observed in 90% of biopsies. Erythropoietin and pimonidazole adduct staining did not always colocalize within tumors, but there was a significant positive correlation between levels of microregional erythropoietin expression and pimonidazole binding. CONCLUSIONS: The coexpression of erythropoietin and EPOR in tumor cells suggests that erythropoietin may potentially function as an autocrine or paracrine factor in head and neck cancer. The expression of the hypoxia-inducible protein erythropoietin in tumor cells correlates with levels of tumor hypoxia.  相似文献   
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