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991.
Residual renal function (RRF) is an important parameter in the management of patients on chronic dialysis. The aim of this cross-sectional study was to determine the efficacy of serum cystatin C (CysC) for RRF estimation in 20 children (16 boys, 4 girls; median age 13.4 years) undergoing peritoneal dialysis (PD). For studies of correlation with serum CysC, the average of creatinine clearance rate (Ccr) and urea clearance rate (Curea), Kt/Vurea, and weekly Ccr were evaluated as parameters reflecting RRF. The serum CysC level was found to be negatively correlated with urine volume (r = −0.717, P < 0.001), average of Ccr and Curea(r = −0.851, P < 0.001), total and renal weekly Ccr (r = −0.795, P < 0.001; r = −0.845, P < 0.001, respectively), and renal Kt/Vurea (r = −0.793, P < 0.001) and positively correlated with peritoneal weekly Ccr (r = 0.738, P < 0.001) and peritoneal Kt/Vurea (r = 0.785, P < 0.001). There was no significant association with total Kt/Vurea (r = −0.335, P = 0.148). In non-anuric group of patients, serum CysC had no link to peritoneal Kt/Vurea (r = 0.573, P = 0.066), but was negatively correlated with renal Kt/Vurea (r = −0.609, P = 0.047). In the multiple regression analysis, renal Kt/Vurea significantly contributed to log CysC concentration rather than peritoneal Kt/Vurea. The results of this study suggest that serum CysC could be an appropriate marker for RRF, independent of total and peritoneal Kt/Vurea.  相似文献   
992.
Melasma is triggered by various factors including ultraviolet radiation and estrogen; however, its pathogenesis is unclear. To investigate the inflammatory features of melasma lesions as triggers for this disorder, 197 women with melasma who attended Asan Medical Center and Kangskin Clinic, Seoul, from June 2011 to October 2011 completed a questionnaire concerning triggering or aggravating factors. These cases were divided into “non‐inflammatory” and “inflammatory” groups. Skin biopsies and immunostaining for CD68, CD117, and leukocyte common antigen (LCA) were performed in the lesional and peri‐lesional skin of ten cases in the non‐inflammatory group and nine cases in the inflammatory group. Among the 197 subjects (mean age, 41.5 years; mean age of melasma onset, 33.8 years), 50 patients (25.4%) were categorized into the inflammatory group. This group comprised cases that had inflammatory symptoms and events that triggered the melasma lesions. The lesional dermis contained more CD68+ melanophages, CD117+ mast cells, and LCA+ leukocytes in the inflammatory group than in the non‐inflammatory group. Inflammatory clinical features and an increased number of inflammatory cells in the lesion may be involved in the development of melasma in Asian skin.  相似文献   
993.

Background

Spleen-preserving distal pancreatectomy can be performed safely and effectively by resecting both splenic vessels (Warshaw procedure) [14]. This simplified spleen-preserving technique might also be applied to minimally invasive distal pancreatectomy of benign and borderline malignant tumor [5, 6].

Methods

Although the conservation of both splenic vessels is paramount to preserving the spleen during laparoscopic distal pancreatectomy, preservation of the splenic vessels is not always possible, especially under the following conditions: (1) relatively large tumor, (2) associated with chronic pancreatitis, (3) tumor abutting splenic vascular structures, and (4) bleeding during the splenic vessel conserving procedure, which are potential indications of laparoscopic extended Warshaw procedure. Patient preparation and position was the same as that described in our previous study [7].

Results

During the study’s time period, 38 consecutive patients underwent laparoscopic spleen-preserving distal pancreatectomy. Of those, five patients underwent a laparoscopic extended Warshaw procedure, which all included among 16 patients of extended distal pancreatectomy by dividing the pancreas at the pancreatic neck. All patients were women with a median age of 55 (range, 38–75) years. Median total operation time and blood loss were 215 (range, 200–386) minutes and 100 (range, 0–300) ml, respectively. The median length of hospital stay was 8 (range, 5–15) days. All of postoperative complications (two grade A and two grade B postoperative pancreatic fistula; one grade A bleeding) were able to be treated conservatively. During the median follow-up period of 11 (range, 7–42) months, one focal splenic infarction and one gastric varix were noted; however, no clinically significant complications were reported.

Conclusions

Laparoscopic spleen-preserving extended distal pancreatectomy with resection of both the splenic vessels is feasible and safe [8]. This surgical technique is thought to increase the chance of preservation of the spleen with minimally invasive distal pancreatectomy in well-selected benign or borderline malignant tumor of the distal pancreas.  相似文献   
994.
995.
996.

Background

The clinical usefulness of tumor markers as predictors of treatment outcome in patients with stomach cancer after radical gastrectomy has been poorly defined. The purpose of this study was to evaluate a comprehensive understanding of the impact of early postoperative tumor marker normalization on survival after gastrectomy.

Methods

Between January 2001 and December 2007, we enrolled 206 patients who had received radical gastrectomy as an initial treatment and had elevated carcinoembryonic antigen (CEA) (>5 ng/mL) or carbohydrate antigen (CA) 19-9 (>37 U/mL) levels. Early tumor marker response was defined as a normalization of preoperative CEA or CA19-9 values 1–2 months after gastrectomy.

Results

The mean patient age was 61 years (range 29–84 years), and 139 patients (67.5 %) were male. Early tumor marker response was identified in 150 of 206 (72.8 %) patients. Of the patients, 49 (23.8 %), 41 (19.9 %), and 116 (56.4 %) were stages I, II, and III, respectively, according to the seventh edition of the American Joint Commission on Cancer (AJCC) staging system. Both disease-free survival (DFS) and overall survival (OS) were significantly longer in patients with tumor marker response compared with nonresponse (61.5 vs. 37.6 months; P = 0.010 and 71.3 vs. 50.9 months; P = 0.008, respectively). Multivariate analyses showed that high CA19-9 level, early tumor marker response, and tumor, node, metastasis classification system stage were independent predictors of DFS and OS (P < 0.05).

Conclusions

Early CEA or CA19-9 normalization after radical gastrectomy is a strong prognostic factor for gastric cancer, especially in patients with high preoperative levels of tumor markers.  相似文献   
997.
为提高预测囊外扩展(ECE)和精囊浸润(SVI)的准确性,我们评估了影响MRI(磁共振成像)预测的变量,并估计了这些变量对术前MRI分期和病理结果之间准确性的影响。121名行机器手前列腺癌根治术(RALP)的局限性或局限性晚期前列腺癌病人,经直肠活检后,所有入选病人都接受了MRI的检查进行分期诊断。经过RALP后,只有43.8%(53/121)的病人与MRI的预测分期相匹配。与在ECE预测中的匹配组相比,非匹配组的初始前列腺特异抗原(PSA)明显高于匹配组(非匹配组12.8ng mL-1,匹配组8.1ng mL-1,P=0.048).在对SVI的预测中,非匹配组中,初始PSA8.1w.17.3ng mL-1,P=0.009和穿刺活检Gleason评分6.5w.7.6,P=-0.035均显著高于匹配组。如果把10ng mL-1和20ng mL-1的PSA水平作为临床临界值,预测ECE时,对于PSA水平高于20ng mL-1的病人,MRJ准确性会下降(75.6%,64.5%,37.5%,P=0.01);对这组病人预测SVI时,MRI的准确性也会明显下降(91.5%,77.4%,37.5%,P〈0.01)。如果把Gleason评分为7分作为临床临界值,对Gleason评分高于7分的病人,预测SvI时MRI的准确性也会显著下降(93.9%,82.1%,62.9%,P=0.01)。因此,对于这些患者,为了获得前列腺癌根治术过程中的切缘阴性,能提供大量信息的是手术发现而不是活检后的MRI图像,暗示在前列腺活检以前进行MRI检查在临床上更有优势。  相似文献   
998.
Embryonic stem (ES) cell transplantation represents a potential means for the treatment of degenerative diseases and injuries. As appropriate distribution of transplanted ES cells in the host tissue is critical for successful transplantation, the exploration of efficient strategies to enhance ES cell migration is warranted. In this study we investigated ES cell migration under the influence of various extracellular matrix (ECM) proteins, which have been shown to stimulate cell migration in various cell models with unclear effects on ES cells. Using two mouse ES (mES) cell lines, ESC 26GJ9012-8-2 and ES-D3 GL, to generate embryoid bodies (EBs), we examined the migration of differentiating cells from EBs that were delivered onto culture surfaces coated with or without collagen I, collagen IV, Matrigel, fibronectin, and laminin. Among these ECM proteins, collagen IV exhibited maximal migration enhancing effect. mES cells expressed α2 and β1 integrin subunits and the migration enhancing effect of collagen IV was prevented by RGD peptides as well as antibodies against α2 and β1 integrins, indicating that the enhancing effect of collagen IV on cell migration was mediated by α2β1 integrin. Furthermore, staining of actin cytoskeleton that links to integrins revealed well-developed stress fibers and long filopodia in mES cells cultured on collagen IV, and the actin-disrupting cytochalasin D abolished the collagen IV-enhanced cell migration. In addition, pretreatment of undifferentiated or differentiated mES cells with collagen IV resulted in improved engraftment and growth after transplantation into the subcutaneous tissue of nude mice. Finally, collagen IV pretreatment of osteogenically differentiated mES cells increased osteogenic differentiation-like tissue and decreased undifferentiation-like tissue in the grafts grown after transplantation. Our results demonstrated that collagen IV significantly enhanced the migration of differentiating ES cells through α2β1 integrin-mediated actin remodeling and could promote ES cell transplantation efficiency, which may be imperative to stem cell therapy.  相似文献   
999.
1000.

Purpose

To estimate the effect of splenic artery embolization (SAE) on blood flow in orthotopic liver transplantation (OLT) recipients with splenic artery steal syndrome (SASS) based on changes in caliber of related arteries upon serial computed tomography (CT) scans.

Methods

Between 2004 and 2007, nine OLT recipients with SASS underwent SAE. They had CT scans before and after SAE: short-, mid-, and long-term, ie, approximately 1 week, 1 month, and 1 year, respectively. The diameters of the celiac axis (CA), common hepatic artery (CHA), and splenic artery (SA) were measured with arterial phase of each CT scan and the ratios of SA to CHA diameter (SA/CHA) calculated to analyze their changes during the follow-up period.

Results

The diameters of celiac axis, CHA, and SA and SA/CHA changed most rapidly during the short-term period. The CHA diameter significantly increased short-term post-SAE by CT and slightly decreased thereafter. However, the mid-term and long-term post-SAE CT values were still significantly greater than those on the pre-SAE CT. The SA diameter steadily decreased throughout the follow-up. The SA/CHA decreased until the mid-term. The SA diameter and SA/CHA were significantly smaller upon mid-term and long-term post-SAE CT compared with those at pre-SAE CT.

Conclusions

The effect of SAE to improve hepatic arterial flow in OLT recipients with SASS might be expected for at least approximately one year. The effect maximally occurred during the short-term after SAE on the basis of changes in the caliber of related arteries upon CT.  相似文献   
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