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991.
992.

Background

Although previous studies have suggested that low preoperative 25-hydroxyvitamin D (25-OHD) is a risk factor for hypocalcemia after total thyroidectomy, the impact of preoperative 25-OHD on calcium (Ca)/parathyroid hormone (PTH) kinetics in the immediate postoperative period remains unclear. The study compared the postoperative Ca/PTH kinetics between different preoperative 25-OHD levels.

Patients

A total of 281 patients who underwent a total thyroidectomy were analyzed. Serum Ca was measured preoperatively within 1 h after surgery (Ca-D0) and on the following morning (Ca-D1). Preoperative 25-OHD was also measured after overnight fasting while postoperative PTH was checked at skin closure on day 0 (PTH-D0) and on the following morning on day 1 (PTH-D1). The Ca/PTH kinetics were compared between three groups (group I: preoperative 25-OHD < 10 ng/mL; group II: 25-OHD = 10–20 ng/mL; group III: 25-OHD > 20 ng/mL).

Results

Group I had significantly lower preoperative Ca (p = 0.016) and Ca-D0 (p = 0.036) but higher PTH-D1 (p = 0.015) than groups II and III. PTH-D0, Ca-D1, and the rate of clinically significant hypocalcemia were similar in the three groups. Group I had a significantly smaller Ca drop (?0.02 vs. 0.01 and 0.02 mmol/L, p = 0.011) and a tendency for a significantly smaller PTH drop (0.4 vs. 0.5 and 1.0 pmol/L, p = 0.073) than groups II and III. PTH-D1 (OR = 1.550) and 25-OHD (OR = 0.958) were independent factors for Ca drop from day 0 to day 1.

Conclusions

Although group I began with lower serum Ca, those patients tended to have a greater PTH response to Ca drop and so preoperative 25-OHD did not significantly affect the overall Ca kinetics from preoperative to day 1.  相似文献   
993.

Background

Although differentiated thyroid carcinoma (DTC) rarely develops distant metastases, the present study was performed to evaluate factors that affect the survival of patients with DTC who present with distant metastasis.

Methods

Among 4,989 patients who underwent thyroid surgery for DTC, 82 presenting with distant metastasis were analyzed. Based on radioiodine (131I) avidity and the thyroid-stimulating hormone-stimulated serum thyroglobulin (sTg) level at the time of metastasis, patients were divided into three groups: group 1 (131I uptake + sTg ≤ 215 ng/mL, n = 46), group 2 (131I uptake + sTg > 215 ng/mL, n = 24), group 3 (no 131I uptake, n = 12). Disease-specific survival (DSS) was estimated using the Kaplan–Meier method. Factors predicting the outcome were evaluated using Cox proportional hazard regression analysis.

Results

The age of patients (p = 0.04), frequency of follicular thyroid carcinoma (p = 0.002), tumor size (p < 0.001), and number of multiple metastatic sites (p = 0.004) differed significantly among the groups. With a median follow-up after surgery of 72 months, the 5- and 10-year DSSs for all patients were 84 and 69 %, respectively. The predictors of survival were age (p = 0.004), symptoms at the time of presentation (p = 0.045), histology (p = 0.01), sites of metastasis (p = 0.03), and 131I avidity and sTg level at the time of metastasis (p = 0.002). In the multivariate analysis, age, histology, and 131I avidity and sTg level at the time of metastasis remained significant factors for survival.

Conclusions

Certain DTC patients with distant metastasis demonstrate favorable outcomes dependent on age, histology, and 131I avidity and sTg level at the time of metastasis.  相似文献   
994.

Background

The purpose of the present study was to determine whether intrahepatic injection of 131I-lipiodol (Lipiodol) is effective against recurrence of surgically resected hepatocellular carcinoma (HCC).

Methods

From June 2001 through March 2007, this nationwide multi-center prospective randomized controlled trial enrolled 103 patients 4–6 weeks after curative resection of HCC with complete recovery (52: Lipiodol, 51: Control). Follow-up was every 3 months for 1 year, then every 6 months. Primary and secondary endpoints were recurrence-free survival (RFS) and overall survival (OS), respectively, both of which were evaluated by the Kaplan–Meier technique and summarized by the hazard ratio (HR). The design was based on information obtained from a similar trial that had been conducted in Hong Kong.

Results

The Lipiodol group showed a small, and nonsignificant, improvement over control in RFS (HR = 0.75; 95 % confidence interval [95 % CI] 0.46–1.23; p = 0.25) and OS (HR = 0.88; 95 % CI 0.51–1.51; p = 0.64). Only two serious adverse events were reported, both with hypothyroidism caused by 131I-lipiodol and hepatic artery dissection during angiography.

Conclusions

The randomized trial provides insufficient evidence to recommend the routine use of 131I-lipiodol in these patients.  相似文献   
995.

Background

Endoscopic submucosal dissection (ESD) is a technically demanding procedure, and exposure of the submucosa depends on the action of gravity and submucosal injection. The aim of the study was to investigate the effectiveness of the Endolifter® as a traction device for enhancing submucosal visualization during ESD.

Methods

This was a prospective ex vivo comparative study conducted between September 2010 and March 2011 in the Prince of Wales Hospital. Consecutive ESDs were performed by four experienced endoscopists in an ex vivo ESD model with or without the Endolifter®. The Endolifter® allows simultaneous grasping, retracting and lifting of the mucosa during ESD, resulting in exposure of the submucosa. Each of the procedures were recorded and reviewed later by two independent assessors. The outcome measures included the proportion of time that the submucosa was visualized during the procedures (SM ratio), procedural times, perforation rates, amount of submucosal injections, and the difficulty of the procedure.

Results

Forty-eight gastric ESD procedures were performed on the model. The SM ratio was higher in the Endolifter® group (P = 0.007), particularly for lesions located at the antrum (P < 0.001). The time required for submucosal dissection and the total procedural time were also less in the Endolifter® group. The endoscopists rated the ESD procedures in the Endolifter® group as less difficult (P = 0.033).

Conclusions

The Endolifter® improved submucosal visualization during gastric ESD and reduces the difficulty of performing the procedures. The device may improve the ease of performing ESD in low-volume centers or large mucosal lesions.  相似文献   
996.

Background

The submucosal endoscopy provide not only a reliable methods of access and closure for peritoneoscopy, but also an endoscopic working space for full-thickness resection. The aim of this study was to report the clinical outcome of submucosal endoscopy for pure natural orifice transluminal endoscopic surgery.

Methods

We prospectively evaluated 10 patients who received submucosal endoscopies. The indications of submucosal endoscopy were transgastric peritoneoscopy (TGP) and endoscopic full-thickness resection (EFTR) of a gastric subepithelial tumor. All procedures were performed with a standard gastroscope under conscious sedation with the balanced propofol method in the endoscopic unit. After a 40 mm submucosal tunnel was created using an endoscopic submucosal dissection technique, (1) in TGP, balloon dilation of a serosal puncture and intraperitoneal exploration was performed; (2) in EFTR, a full-thickness incision and snaring resection was performed. Closure of the mucosal incision was performed by endoclips.

Results

All cases were technically feasible. The mean times for creating the submucosal tunnel, main procedure (peritoneal exploration or resection), and closure were acceptable (10.44 ± 2.42 minutes, 18.80 ± 9.41 minutes, and 5.63 ± 2.17 minutes, respectively). The mean hospital stay was 3.8 ± 1.48 days. All TGPs were diagnostic (4 peritoneal carcinomatosis and 1 tuberculosis). En bloc and complete resections were possible in all EFTRs (3 gastrointestinal stromal tumors and 2 schwannomas; mean tumor size, 20.8 ± 3.27 mm). There were no procedure-related complications, such as significant bleeding or peritonitis.

Conclusions

Human applications of submucosal endoscopy under conscious sedation for pure NOTES were feasible and safe.  相似文献   
997.

Background

The transosseous-equivalent (TOE) repair of the rotator cuff tears was invented to make up for several shortcomings of the double-row (DR) repair. However, no studies have compared the clinical aspects of the DR repair and the TOE technique, supporting the superior results of the TOE technique over the DR repair, including the benefit of minimizing surgical steps. We asked whether differences existed between the two repairs regarding clinical outcomes, time and costs.

Materials and methods

Subjects included 55 using the DR repair and 119 using the TOE repair for the medium to large sized rotator cuff tears. Clinical outcomes were measured with a Visual Analog Scale, American Shoulder and Elbow Surgeons score, Constant score, and shoulder strength. For practical aspects, operative time and number of suture anchors used for the medial and lateral rows were compared.

Results

Both repairs brought substantial improvements in pain and function. However, significant differences were not detected between the repairs in all the clinical measurements. Regarding operative time and costs, in the medium size tears, a statistical difference was found only in the anchors used for the lateral row. In the large size tears, the DR repair required more operation time than the TOE repair, while the TOE repair used more anchors for the lateral row.

Conclusion

This study failed to demonstrate clinical differences between the techniques. However, when stratifying rotator cuff tears according to the tear sizes, significant differences were found in operative time and cost: the DR repair had the advantage of cost effectiveness by saving anchors for the lateral row, while the TOE repair required less operative time with more anchors used for the lateral row in the large size tears. This finding provides evidence to support the use of the TOE repair to reduce surgical steps.  相似文献   
998.

Background

Posterior retroperitoneoscopic adrenalectomy (PRA) has several benefits compared with transperitoneal adrenalectomy in that it is safe and has a short learning curve. In addition, it provides direct short access to the target organ, prevents irritation to the intraperitoneal space, and does not require retraction of adjacent organs.1 3 We have performed several cases of robot-assisted PRA using single-port access for small adrenal tumors. This multimedia article introduces the detailed methods and preliminary results of this procedure.

Methods

Five patients underwent single-port robot-assisted PRA between March 2010 and June 2011 at our institution. During the procedure, patients were placed in a prone jackknife position with their hip joints bent at a right angle (Fig. 1). A 3 cm transverse skin incision was made just below the lowest tip of the 12th rib (Fig. 2), and the Glove port (Nelis, Kyung-gi, Korea) was placed through the skin incision while maintaining pneumoretroperitoneum (Fig. 3). CO2 was then insufflated to a pressure of 18 mm Hg to create an adequate working space. A 10 mm robotic camera with a 30-degree up view was placed at the center of the incision through the most cephalic portion of the Glove port. A Maryland dissector or Prograsp forceps (Intuitive Surgical, Inc., Sunnyvale, CA) was placed on the medial side of the incision, and Harmonic curved shears (Intuitive Surgical) were placed on the lateral side of the incision (Fig. 4). Using the Maryland dissector and the harmonic curved shears, the Gerota fascia is opened, perinephric fat is dissected, and the kidney upper pole is mobilized to expose the adrenal gland (Fig. 5). Gland dissection starts with lower margin detachment from the upper kidney pole in a lateral to medial direction (Fig. 6). After dissecting the adrenal gland from surrounding adipose tissue and medial isolation of the adrenal central vein, the vessel is ligated with a 5 mm hemolock clip (Fig. 7). Patient clinicopathologic data were analyzed retrospectively.

Results

The mean patient age was 56.6 ± 8.7 (range, 47–69) years. Right and left side approaches were used in two and three patients, respectively. All cases were adrenal cortical adenoma. The mean tumor size was 1.48 ± 0.28 (range, 1.0–1.7) cm. The mean surgery duration (skin to skin) was 159.4 ± 57.6 (range, 103–245) minutes, and the mean estimated blood loss was 46.0 ± 56.8 (range, 5–120) ml. The average time to oral intake and postoperative hospital stay were 0.65 ± 0.11 (range, 0.54–0.79) days and 4.0 ± 2.23 (range, 3–8) days, respectively. There were no conversions to open surgery or postoperative compli- cations.

Discussion

Some trials of minimally invasive single-access surgery of the adrenal gland have recently been performed.4 , 5 However, these new techniques have several limitations as a result of restrictions on instrumentation movement because of the small access ports used and relatively low-quality images produced. The recent introduction of the da Vinci S surgical robot system (Intuitive Surgical) to endoscopic surgery has improved instrumental dexterity and provided the surgeon with an ergonomically designed operating system. This system is also potentially safer and more meticulous in performing operations than endoscopic procedures as a result of a 3-D, magnified, stable operative view.6 , 7 The advantages of the da Vinci S surgical robot system and the numerous benefits of the posterior retroperitoneal approach motivated us to utilize single-port robot-assisted PRA. The primary selection criteria were small tumor size and a minimal amount of periadrenal fatty tissue because robot-assisted PRA using single-port access provides a small operative space, which causes manipulation problems when tumors are large. To ensure the safe application of these new techniques, we recommend that novice surgeons begin using single-port robot-assisted PRA for smaller tumors < 2 cm in patients with a body mass index of < 30 kg/m2, gradually extending the size and body mass index as they accumulate experience. Although robot-assisted PRA using single-port access could not be compared with the other robotic adrenalectomy techniques in this study, the potential advantages of this approach compared to conventional robot-assisted transperitoneal adrenalectomy include a reduction in postoperative ileus, bacterial contamination, and intestinal complications because the peritoneal cavity is not opened, in addition to a reduction in postoperative pain because of its minimally invasive nature.

Conclusions

Our initial experiences with robot-assisted PRA using single-port access assured us of its safety and feasibility for the resection of small adrenal tumors. Although single-port robot-assisted PRA appears to be safe and feasible, further experience and research is required to optimize patient selection criteria and verify its advantages over the traditional three-incision PRA technique.  相似文献   
999.
1000.

Background

Preoperative assessment of the nipple–areolar complex (NAC) is invaluable when considering nipple-sparing mastectomy. Our hypothesis is that breast magnetic resonance imaging (MRI) may predict involvement of the NAC with tumor.

Methods

Clinical, histopathologic, and imaging data were compiled for patients who underwent preoperative breast MRI followed by mastectomy or nipple-sparing mastectomy for malignancy between 2006 and 2009. Blinded rereview of all MRI studies was performed by a breast MRI imager and compared to initial MRI findings. Multivariate analysis identified variables predicting NAC involvement with tumor.

Results

Of 77 breasts, 18 (23 %) had tumor involving or within 1 cm of the NAC. The sensitivity of detecting histopathologically confirmed NAC involvement was 61 % with history and/or physical examination, and 56 % with MRI. Univariate analysis identified the following variables as significant for NAC involvement: large tumors near the nipple on preoperative MRI, node-positive disease, invasive lobular carcinoma, advanced histopathologic T stage, and neoadjuvant chemotherapy. On multivariate analysis, only tumor size >2 cm and distance from tumor edge to the NAC <2 cm on MRI maintained significance. Pearson correlation coefficient for MRI size compared to histopathologic size was 0.53 (P < 0.0001).

Conclusions

MRI is not superior to thorough clinical evaluation for predicting tumor in or near the NAC. However, MRI-measured tumor size and distance from the NAC are correlated with increased risk of NAC involvement. The combination of preoperative history and physical examination, tumor characteristics, and breast MRI can aid the surgeon in predicting a tumor-involved nipple more than any single modality alone.  相似文献   
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