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71.
Laparoscopic Heller myotomy (LHM) has become the standard treatment option for achalasia. The incidence of esophageal perforation reported is about 5%–10%. Robotically assisted Heller myotomy (RAHM) is emerging as a safe alternative to LHM. Data comparing the two approaches are scant. The aim of this study was to compare RAHM with LHM in terms of efficacy and safety for treatment of achalasia. A total of 121 patients underwent surgical treatment of achalasia at three institutions. A retrospective review of prospectively collected perioperative data was performed. Patients were divided into two groups: group A (RAHM), 59 patients, and group B (LHM), 62 patients. All the operations were completed using minimally invasive techniques. There were 63 women and 58 men, with a mean age of 45 ±19 years (14–82 years). Fifty-one percent of patients in group A and 95% of patients in group B reported weight loss. Duration of symptoms was equal for both groups. Dysphagia was the main complaint in both groups (P = NS). There was no difference in preoperative endoscopic treatment in both groups (44% versus 27%, P = NS). Operative time was significantly shorter for LHM in the first half of the experience (141 ± 49 versus 122 ± 44 minutes, P < .05). However, in the last 30 cases there was no difference in operative time between the groups (P = NS). Intraoperative complications (esophageal perforation) were more frequent in group B (16% versus 0%). The incidence of postoperative heartburn did not differ by group. There were no deaths. At 18 and 22 months, 92% and 90% of patients had relief of their dysphagia. This study suggests that RAHM is safer than LHM, because it decreases the incidence of esophageal perforation to 0%, even in patients who had previous treatment. At short-term follow-up, relief of dysphagia was equally achieved in both groups. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation). This study was supported in part by a grant provided by Intuitive Surgical, Inc. and Ethicon Endo-Surgery, Inc.  相似文献   
72.
Susan Nixon died in 1881 following a surgical error. Her surgeon, Dr W. E. Warren, excised a normal 7-month gravid uterus under the misapprehension that he was removing a tubular pregnancy. It is believed that Mrs Nixon was the first woman in Australia to have an abdominal hysterectomy and the second to have a live Caesarean section. The surgical misadventure that resulted in Mrs Nixon's death became a public scandal, which gained currency through both parliamentary debate and the popular press. The purpose of referring to this case is to explore the mechanisms of accountability that surgeons faced in the 1880s--a decade of rapid change in the practice of surgery. The response of late nineteenth century society to surgical error and the resultant reaction of the medical profession have resonances that are relevant to surgeons practising today.  相似文献   
73.
Both benign and malignant breast lesions may exhibit intense contrast enhancement when imaged using gadolinium-enhanced MRI. We propose a quantitative approach for fitting dynamic signal intensity (SI) data that may distinguish benign from malignant lesions. We studied 78 lesions in 75 women (18 malignancies, 16 fibroadenomas, and 44 other benign breast lesions) to determine the potential of this model for decreasing false-positive MR results. Twenty-eight lesions showed no enhancement; all were benign. One lesion showed a complex pattern not amenable to region-of-interest analysis and was considered a false positive. SI versus time data for the remaining 49 lesions were fit to the proposed model. We found that one parameter, M, the normalized slope of the SI enhancement profile evaluated at half the maximal signal intensity, seemed to be highly correlated with malignancy and offered improved discrimination between malignant and benign lesions compared to a previously published two-point slope method.  相似文献   
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Because urine ion excretion varies throughout the day, clinicians monitor 24 h urine samples to measure ion excretion and supersaturation in kidney stone patients. However, these results are averages and may not reflect maximal supersaturation which drives stone formation. We measured ion excretion and saturation in genetic hypercalciuric stone-forming rats on both a normal or low calcium diet over 0-3, 3-6 and 6-24 h using two feeding protocols, where the daily food allotment was fed either as a bolus or divided into three portions. With a normal calcium diet, urine calcium, oxalate, volume, and calcium oxalate supersaturation were significantly greater on the bolus compared to the divided feeds in the prandial and postprandial periods. Bolus eaters also excreted more calcium and oxalate and had increased volume over 24 h. Maximal calcium oxalate supersaturation was greater during the initial time periods than during the entire 24 h, regardless of the feeding schedule. With the low calcium diet, the effect of bolus feeding was reduced. Thus, urine ion excretion and supersaturation vary with the type of feeding. If these results are confirmed in man, it suggests that eating as a bolus may result in greater prandial and postprandial calcium oxalate supersaturation. This may increase growth on Randall's plaques and promote stone disease.  相似文献   
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77.
BACKGROUND: Optimal surgical outcomes are dependent on an appreciation of comorbid conditions that may handicap results. The purpose of this retrospective analysis was to delineate risk factors for complications after autologous breast reconstruction. STUDY DESIGN: An institutional database was constructed of patients who underwent autologous breast reconstruction from 1998 to 2005. Variables captured included age, diabetes and smoking status, prereconstruction radiation therapy, concomitant breast resection, preoperative albumin, flap type, and body mass index (BMI; based on World Health Organization classifications: BMI>25, overweight; >30, obese). The primary outcome was noninfectious wound complications (NIWC), a novel classification based on the extent of tissue derangement and need for operative intervention. Secondary outcomes were wound infection, hematoma, hernia, and fat necrosis. Statistical analysis was performed using chi-square tests and multiple logistic regression. RESULTS: The analysis included 200 flaps (transverse rectus abdominis myocutaneous [TRAM]=171; latissimus dorsi=29) in 180 patients. There were 19 infections (9.5%), 3 total flap losses (1.5%), 14 hematomas (7%), and 11 donor-site hernias (6%). The incidences of fat necrosis and any NIWC were 18% and 36%, respectively. Mean followup was 13.1 months (range 1.1 to 51.7 months). Multiple logistic regression demonstrated that obesity (BMI>30) is a statistically significant independent risk factor for any NIWC (hazards ratio=6.58; 95% CI, 2.85 to 15.18; p < 0.01) and for NIWC requiring operative treatment (NIWC>or=3; hazard ratio=6.23; 95% CI 2.15 to 18.05; p < 0.01). Increased BMI predicts NIWC, NIWC requiring operative intervention, and wound infection (p < 0.01). CONCLUSIONS: These data suggest that obesity is a strong predictor of simple and complex NIWC and of wound infection after autologous breast reconstruction. Obese patients should be counseled about their significantly increased risk of experiencing these unwanted outcomes.  相似文献   
78.
Tension pneumocephalus is an unusual, potentially life-threatening complication of frontal fossa tumors. We present an uncommon case of a frontoethmoidal osteoma causing a tension pneumocephalus and neurological deterioration prompting a combined endonasal ethmoidectomy and bifrontal craniotomy with craniofacial approach for resection. A 68-year-old man presented with a 1-week history of worsening headache, slowness of speech, and increasing confusion. Standard computed tomography scan revealed a marked tension pneumocephalus with ventricular air and 1-cm midline shift to the right. Further studies showed a calcified left ethmoid mass and a left anterior cranial-base defect. A team composed of neurosurgery and otolaryngology performed a combined endonasal ethmoidectomy and bifrontal craniotomy with craniofacial approach to resect a large frontoethmoid bony tumor. No abscess or mucocele was identified. The skull base defect was repaired with the aid of a transnasal endoscopy, a titanium mesh, and a pedunculated pericranial flap. Postoperatively, the pneumocephalus and the patient's symptoms completely resolved. Pathology was consistent with a benign osteoma. This is an uncommon case of a frontoethmoidal osteoma associated with tension pneumocephalus. Recognition of this entity and timely diagnosis and treatment, consisting of an endonasal ethmoidectomy and a bifrontal craniotomy with craniofacial approach, may prevent potential life-threatening complications.  相似文献   
79.
80.
Pudendal nerve palsy is a reported complication of hip arthroscopy. We report a technique using a deflated taped beanbag rather than a perineal post. The patient is placed in the supine or lateral position on a fracture table. The beanbag is contoured around the patient’s flank and thorax. The distal aspect of the beanbag is placed no further than the iliac crest, and care is taken to avoid compression of the posterior aspect of the axillary region or the posterior humerus. The molded beanbag is deflated, a blanket is positioned over the abdomen and lower thorax, and with the use of 3-in-wide cloth tape, the patient and beanbag are secured to the operative table circumferentially. The superior margin of the deflated beanbag remains firm, preventing compression of the thorax and avoiding compromised ventilation. The arm on the operative side is placed across the chest and secured to avoid obstruction of the operative field. This patient positioning provides sufficient stability for adequate traction and good visualization while minimizing the risk of a pudendal nerve palsy.  相似文献   
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