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101.
Background We assessed whether new parameter that considers both tumor volume change and necrosis rate predicts metastasis-free survival of localized osteosarcoma patients. We also evaluated relationship between tumor volume change and necrosis rate or metastasis-free survival. Methods We retrospectively reviewed 151 patients with stage II osteosarcoma who were treated with surgery and neoadjuvant chemotherapy. The tumor volume change was measured and calculated based on pre- and postchemotherapy magnetic resonance images. The mean metastasis-free interval was 83.1 months. We calculated adjusted tumor necrosis rate as following formula: 100–(100–necrosis rate) × postchemotherapy/prechemotherapy tumor volume. Survival and logistic regression analyses were used to evaluate the correlation among size parameters, tumor necrosis rate and survival. Results The 5-year metastasis-free survival rate of 151 patients was 71.4% (95% CI, 67.7–75.1%). American Joint Committee on Cancer (AJCC) stage IIB (RR 2.27; 95% CI, 1.11–4.62; P = 0.025) and poor adjusted tumor necrosis rate (RR 2.02; 95% CI, 1.05–3.89; P = 0.035) independently correlated with metastasis-free survival period. Further, tumor volume change independently correlated with necrosis rate. Decreased tumor volume could predict good response, with sensitivity of 80.2%, specificity of 68.6%, and positive predictive value (PPV) of 74.7%. Increased or stable tumor volume could predict poor response, with sensitivity of 68.6%, specificity of 80.2%, and PPV of 75.0 %. Conclusion The necrosis rate adjusted by the tumor volume change is an independent prognostic factor in osteosarcoma. This adjusted tumor necrosis rate may serve as a basis for risk-adapted therapy in combination with other prognostic factors.  相似文献   
102.
Background and objectives In breast cancer, the expression pattern of CXCR4 may be correlated with the degree of axillary lymph node involvement. The aim of this study was to evaluate the contributing factors that contribute to the correlation between CXCR4 expression and axillary lymph node metastasis in breast cancer. Methods Between August 1997 and August 2002, sections of paraffin-embedded tissue were obtained from 107 patients who received optimal treatment for breast cancer. The expression of CXCR4 was evaluated by immunohistochemical staining. Results A significant correlation was found in the expression of nuclear CXCR4 and lymph node metastasis (P = 0.03). We found a significant correlation between a high nuclear expression of CXCR4 and axillary lymphatic metastasis in estrogen and progesterone receptor negative breast cancer (P = 0.01 and P = 0.01). There was a significant correlation between the high expression of nuclear CXCR4 and axillary lymphatic metastasis in comparisons between positive estrogen and/or progesterone receptor expression and negative expression (P = 0.02). Conclusions Our results showed that high expression of nuclear CXCR4 was significantly correlated with lymph node metastasis in breast cancer. The high expression of nuclear CXCR4 in hormone receptor negative breast cancer was associated with a high possibility of lymph node metastasis.  相似文献   
103.
Bariatric surgery has serious associated medical comorbidity and procedure-related risks and is, thus, considered an intermediate-to-high-risk non-cardiac surgery. Altered respiratory mechanics, obstructive sleep apnea (OSA), and less often, pulmonary hypertension and postoperative pulmonary embolism are the major contributors to poor pulmonary outcomes in obese patients. Attention to posture and positioning is critical in patients with OSA. Suspected OSA patients requiring intravenous narcotics should be kept in a monitored setting with frequent assessments and naloxone kept at the bedside. Use of reverse Tredelenburg position, preinduction, maintenance of positive end-expiratory pressure, and use of continuous positive airway pressure can help improve oxygenation in the perioperative period.  相似文献   
104.
BACKGROUND: We hypothesized that a dorsomedial locking plate with adjunct screw compression would provide superior rigidity compared to crossed screws for first metatarsocuneiform (MTC) arthrodesis. MATERIALS AND METHODS: In ten matched lower extremity pairs, specimens in each pair were randomly assigned to receive screw fixation or plate with screw fixation. Bone mineral density (BMD) was measured. For the crossed-screw construct, two 4.0-mm cannulated screws were used. One screw was inserted dorsal to plantar beginning from the first metatarsal 10 to 15 mm distal to the joint, and the second was inserted from the cuneiform 8 to10 mm proximal to the joint, medial to the first screw, into the first metatarsal. For the plate construct, a 4.0-mm cannulated compression screw was inserted from the dorsal cortex of the first metatarsal to the plantar aspect of the medial cuneiform. A locking plate was inserted dorsomedially across the MTC joint. Specimens were loaded in four-point bend configuration (displacement rate, 5 mm/min) until failure of the fixation or 3-mm deformation. An extensometer was used to measure deformation. RESULTS: There was no difference in load to failure or stiffness between the two groups. BMD was positively correlated with load to failure in the screw (r = 0.893, p = 0.001) and the plate (r = 0.858, p = 0.001) construct. CONCLUSION: The plate construct with compression screw did not show different rigidity as compared with the screw construct with the numbers available. CLINICAL RELEVANCE: Further investigation of a dorsomedial plate with adjunct screw compression may be warranted for first MTC arthrodesis.  相似文献   
105.
In patients with brachial plexus birth palsy, persistent muscular imbalance across the developing shoulder results in progressive glenohumeral dysplasia, characterized by increased glenoid retroversion, humeral head flattening, and posterior subluxation of the humeral head. Soft-tissue procedures-such as tendon transfers and musculotendinous lengthenings--will provide limited functional improvements in the setting of advanced glenohumeral deformity. For patients with internal rotation contracture and external rotation weakness associated with severe glenohumeral dysplasia, external rotation osteotomy of the humerus may be used to improve global shoulder function. The purpose of this article is to review the history, indications, and surgical technique of external rotation humeral osteotomy for patients with brachial plexus birth palsy.  相似文献   
106.
107.
BACKGROUND/AIM: Increased nitric oxide (NO) generation and action have been suggested to be associated with glomerular hyperfiltration and increased vascular permeability early in diabetes. However, previous studies have primarily focused on the constitutive nitric oxide synthase (cNOS) pathway present in endothelial cells, and the role of the inducible NOS (iNOS) pathway in diabetic nephropathy has remained unclear. This study examined whether high glucose modulates NO synthesis by the iNOS pathway in rat mesangial cells. In addition, the effect of inhibition of the iNOS pathway on fibronectin production was determined to examine the role of the iNOS pathway in high glucose-induced extracellular expansion by mesangial cells. METHODS: NO synthesis by the iNOS pathway was evaluated by nitrite and iNOS mRNA and protein productions. The effects of protein kinase C (PKC) inhibitor and aldose reductase inhibitor on the iNOS mRNA expression and aminoguanidine, a relatively specific inhibitor of the iNOS on fibronectin protein production were examined. RESULTS: High 30 mM glucose concentration led to significant increases in nitrite production of rat mesangial cells upon stimulation with lipopolysaccharide (LPS) plus interferon-gamma (IFN-gamma) compared with control 5.6 mM glucose concentration. Mesangial iNOS mRNA expression and protein production also increased significantly in response to high glucose. The addition of calphostin C, a PKC inhibitor, and 6-bromo-1,3-dioxo-1H-benz[d,e]isoquinoline-2(3H)-acetic acid, an aldose reductase inhibitor, significantly suppressed the enhancement of iNOS mRNA expression in high glucose concentration. High glucose also significantly increased fibronectin protein production of mesangial cells upon stimulation with LPS plus IFN-gamma compared to control glucose. Aminoguanidine reversed this high glucose-induced fibronectin production at dose inhibiting iNOS mRNA expression. CONCLUSIONS: These results indicate that high glucose enhances cytokine-induced NO production by rat mesangial cells, and that the activation of PKC and aldose reductase pathway may play a role in this enhancement. In addition, high glucose-induced NO production by the iNOS pathway may promote extracellular matrix accumulation by mesangial cells under certain condition.  相似文献   
108.
INTRODUCTION: The purpose of this study is to investigate in vitro the effects of serotonin on the rat detrusor. In particular, it examines which drugs inhibit the serotonin-induced detrusor contractions. MATERIALS AND METHODS: Isometric tension changes of isolated rat bladder muscle strips were recorded in an organ bath using a force transducer. Acute effects of serotonin (0.0001-0.01 mM) on resting tension were assessed. Electrical field stimulation (EFS); bethanechol (0.0001-0.01 mM); ATP (1-3 mM)- or KCl (63.5-254 mM)-induced contractions using an application in an organ bath were compared with serotonin-induced contractions. In order to examine the action mechanism of serotonin-induced stimulation, EFS-, bethanechol-, ATP- or KCl-induced contraction on serotonin treatment (0.001 mM) was assessed and serotonin (0.001-0.1 mM) was cumulatively added to the organ bath following preincubation with propranolol, ketanserin, tropisetron, propiverine, sodium nitroprusside or doxazosin. RESULTS: The serotonin-induced response has two phases: an initial transient contraction and a prolonged tonic phase. Serotonin produced a reversible and dose-dependent contraction of the detrusor strips. Responses to bethanechol significantly increased with a concentration of 0.001 mM serotonin (p < 0.05). There was no effect on the responses to ATP, KCl, or EFS on 0.001 mM serotonin. The 5-HT(2) receptor is mainly responsible for serotonin-induced contractions of the detrusor (p < 0.05), while the 5-HT(1) receptor is partially responsible. Doxazosin and propiverine each significantly suppressed the response to serotonin, while sodium nitroprusside and tropisetron each had no effect (p < 0.05). CONCLUSIONS: Because the 5-HT(2) antagonist blocked the effect of serotonin-induced bladder contractions and the stimulation of the adrenoreceptors, the 5-HT(2) antagonist seems to improve lower urinary tract symptoms.  相似文献   
109.
Bae YC  Kim JH  Lee J  Hwang SM  Kim SS 《Annals of plastic surgery》2002,48(4):359-62; discussion 362-4
Palatal lengthening is often emphasized in performing palatoplasty. However, definitive data regarding the method of measuring palatal length and the extent of palatal lengthening expressed quantitatively have not been reported. The authors have devised an easy method of measuring palatal length that can be expressed quantitatively, and they examined the characteristics of various methods of palatoplasty that are presently used commonly. A paper ruler was used to measure both a straight-line and a curved distance while the patient was under general anesthesia before and immediately after the palatoplasty. According to this study, the straight-line distance was lengthened to a significantly greater degree than the curved distance was after pushback palatoplasty for incomplete types of cleft palate and two-flap palatoplasty for complete types. Furlow double-opposing Z-palatoplasty and two-flap palatoplasty appeared to allow for greater palatal lengthening than the pushback palatoplasty. Further investigations will be undertaken to determine the correlation between the extent of palatal lengthening and speech development.  相似文献   
110.
Aggressive surgical management of spinal metastatic disease can provide improvement of neurological function and significant pain relief. However, there is limited literature analyzing such management as is pertains to individual histopathology of the primary tumor, which may be linked to overall prognosis for the patient. In this study, clinical outcomes were reviewed for patients undergoing spinal surgery for metastatic breast cancer. Respective review was done to identify all patients with breast cancer over an eight-year period at a major cancer center and then to select those with symptomatic spinal metastatic disease who underwent spinal surgery. Pre- and postoperative pain levels (visual analog scale [VAS]), analgesic medication usage, and modifed Frankel grade scores were compared on all patients who underwent surgery. Univariate and multivariate analyses were used to assess risks for complications. A total of 16,977 patients were diagnosed with breast cancer, and 479 patients (2.8%) were diagnosed with spinal metastases from breast cancer. Of these patients, 87 patients (18%) underwent 125 spinal surgeries. Of the 76 patients (87%) who were ambulatory preoperatively, the majority (98%) were still ambulatory. Of the 11 patients (13%) who were nonambulatory preoperatively, four patients were alive at 3 months postoperatively, three of which (75%) regained ambulation. The preoperative median VAS of six was significantly reduced to a median score of two at the time of discharge and at 3, 6, and 12 months postoperatively (P < 0.001 for all time points). A total of 39% of patients experienced complications; 87% were early (within 30 days of surgery), and 13% were late. Early major surgical complications were significantly greater when five or more levels were instrumented. In patients with spinal metastases specifically from breast cancer, aggressive surgical management provides significant pain relief and preservation or improvement of neurological function with an acceptably low rate of complications.  相似文献   
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