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91.
High molecular weight DNAs prepared from a variety of human tumors maintained in nude mice were assayed for their ability to transform NIH 3T3 cells. DNAs from 4 of 21 tumors tested induced transformed foci in cultures of NIH 3T3 cells. They were from a Ewing sarcoma line, a glioblastoma line, a leiomyosarcoma line, and a lung carcinoma line. Hybridization analyses of the NIH 3T3 transformant DNAs with a human repetitive sequence as probe revealed that four distinct transforming DNA sequences were transferred to NIH 3T3 cells from the four tumor lines. The transforming DNA in a lung carcinoma line was a human homologue of the oncogene of Kirsten murine sarcoma virus (Ki-ras). On the other hand, the three other transforming DNAs showed no similarity to any known human transforming gene detected by the NIH 3T3 transformation assay. Further analyses with a series of cloned oncogenes as probes revealed that the transforming DNA in a glioblastoma line was a human homologue of the oncogene of 3611-murine sarcoma virus (raf). However, the two transforming DNAs in a Ewing sarcoma line and a leiomyosarcoma line had no sequence homology to any of the cloned oncogenes.  相似文献   
92.

Background  

BRCA1 and BRCA2 are two major tumor suppressor genes for hereditary breast and ovarian cancer. In sporadic breast cancer, although somatic mutations of these genes are rare, loss of heterozygosity (LOH) at BRCA1 and BRCA2 loci is common.  相似文献   
93.

Background

Klotho has been investigated as an anti-aging protein that is predominantly expressed in the distal convoluted tubules in the kidneys and in the choroid plexus of the brain. The purpose of the present study was to determine the relationship between the soluble form of Klotho and renal function in chronic peritoneal dialysis (PD) patients, a relationship which remains poorly understood.

Methods

The soluble Klotho levels in the serum, urine, and peritoneal dialysate obtained from thirty-six PD patients were determined by a sandwich enzyme-linked immunosorbent assay system.

Results

The amount of urinary excreted soluble Klotho over 24?h ranged from 1.54 to 1774.4?ng/day (median 303.2?ng/day; interquartile range [IR] 84.1–498.5), while the serum soluble Klotho concentration ranged from 194.4 to 990.4?pg/ml (mean 553.7?±?210.4?pg/ml). The amount of urinary Klotho excretion was significantly correlated with residual renal function. However, there was no apparent correlation between the serum soluble Klotho levels and the residual renal function. Klotho was also detected in the 24-h dialysate collections. There was a significant correlation between the peritoneal Klotho excretion and the amount of albumin contained in the dialysate collections (r?=?0.798, p?Conclusions The total amount of urinary excreted Klotho, but not the serum level of soluble Klotho, may be a potential biomarker for assessing the residual renal function among PD patients. Whether our findings are also valid for chronic kidney disease patients overall should therefore be evaluated in greater detail.  相似文献   
94.

Purpose

Gastrointestinal stromal tumors (GISTs) should be surgically resected, even those smaller than 5?cm in size, which is the threshold of clinical malignancy for submucosal tumors (SMTs) in the gastrointestinal tract. This study reviewed the use of laparoscopic surgery for gastric partial resection of GISTs or SMTs that were suspected to be GISTs.

Methods

Eighteen patients underwent laparoscopic partial resection of the stomach for GISTs or SMTs. The tumor location was confirmed by intraluminal endoscopy. One-half of the circumference around the tumor was dissected, and the tumor was turned toward the abdominal cavity. The nonresected part of the tumor and the edge of the incision line was lifted up using forceps, and the incision line was closed using laparoscopic stapling devices.

Results

Two cases were diagnosed as GIST by endoscopic biopsy. Six patients underwent endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) examinations, which diagnosed five GISTs. There were 18 tumors smaller than 5?cm, including 10 GISTs, 4 leiomyomas, 3 schwannomas, and one heterotopic pancreas.

Conclusions

Endoscopic ultrasound-guided FNAB is recommended for definite preoperative diagnosis of histopathologically unknown SMTs to determine the indications for surgery. The laparoscopic approach with the assistance of endoscopy is useful for improving the curability, with minimal invasiveness for the partial resection of GISTs.  相似文献   
95.

Purpose

To describe the natural history and identify predictors of cancer-specific survival in patients who experience disease recurrence after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC).

Methods

Of 2,494 UTUC patients treated with RNU without neoadjuvant chemotherapy, 597 patients experienced disease recurrence. A total of 148 patients (25?%) received adjuvant chemotherapy before disease recurrence. Multivariable Cox regression model addressed time to cancer-specific mortality after disease recurrence.

Results

The median time from RNU to disease recurrence was 12?months (interquartile range 5?C22). A total of 491 (82?%) of 597 patients died from UTUC, and 8 patients (1.3?%) died from other causes. The median time from disease recurrence to death of UTUC was 10?months. Actuarial cancer-specific survival estimate at 12?months after disease recurrence was 35?%. On multivariable analysis that adjusted for the effects of standard clinicopathologic characteristics, higher tumor stages [hazard ratio (HR) pT3 vs. pT0?CT1: 1.66, p?=?0.001; HR pT4 vs. pT0?CT1: 1.90, p?=?0.002], absence of lymph node dissection (HR 1.28, p?=?0.041), ureteral tumor location (HR 1.44, p?<?0.0005) and a shorter interval from surgery to disease recurrence (p?<?0.0005) were significantly associated with cancer-specific mortality. The adjusted 6-, 12- and 24-month postrecurrence cancer-specific mortality was 73, 60 and 57?%, respectively.

Conclusions

Approximately 80?% of patients who experience disease recurrence after RNU die within 2?years after recurrence. Patients with non-organ-confined stage, absence of lymph node dissection, ureteral tumor location and/or shorter time to disease recurrence died of their tumor more quickly than their counterparts. These factors should be considered in patient counseling and risk stratification for salvage treatment decision making.  相似文献   
96.
ObjectiveCarcinoma in situ (CIS) is associated with increased risk of progression when found with high-grade non-muscle-invasive bladder cancer, yet its impact is less clear in the upper urinary tract. In the current study, we evaluated the impact of concomitant CIS on recurrence-free survival and cancer-specific survival following radical nephroureterectomy for upper tract urothelial carcinoma (UTUC).Materials and methodsA multi-institutional retrospective cohort of 1,387 patients undergoing radical nephroureterectomy was identified. Concomitant CIS was defined as the presence of CIS in association with another pathologic stage; patients with CIS alone were excluded from the analysis. The presence of concomitant CIS served as the exposure variable with disease recurrence and cancer-specific mortality as the outcomes. Organ-confined disease was defined as AJCC/UICC stage II or lower.ResultsConcomitant CIS was identified in 371 of 1,387 (26.7%) patients and was significantly more common in patients with a previous bladder cancer history, high grade, and high stage tumors. In a multivariable analysis, concomitant CIS was a predictor of disease recurrence (HR = 1.25, P = 0.04) and cancer specific mortality (HR = 1.34, P = 0.05) for patients with organ-confined UTUC, but not in the entire cohort. Other prognostic variables, such as grade, stage, lymphovascular invasion, and lymph node status, were associated with poorer overall and recurrence-free survival for all patients.ConclusionThe presence of concomitant CIS in patients with organ-confined UTUC is associated with a higher risk of recurrent disease and cancer-specific mortality. This information may be useful in refining surveillance protocols and in more appropriate selection of patients for adjuvant chemotherapy.  相似文献   
97.
Objectives: To report our initial experience with transumbilical laparo‐endoscopic single‐site adrenalectomy for adrenal tumors by using a single port with a multichannel cannula and bent laparoscopic instrumentation. Methods: Between December 2009 and December 2010, 30 patients underwent transumbilical laparo‐endoscopic single‐site adrenalectomy at our hospital. The procedure was carried out for adrenal cortical adenoma in 17 patients, adrenal pheochromocytoma in seven patients and other types of tumors in six patients. A multichannel port, bent laparoscopic instruments and Opti4 laparoscopic electrodes were used in all patients. The intraperitoneal space was approached through the umbilicus. The multichannel port was placed through a 2‐cm incision at the inner edge of the umbilicus. A 5‐mm flexible laparoscope was introduced to maintain an adequate laparoscopic view, and surgical specimens were extracted using an Endocatch bag. Results: All procedures were successfully completed, with only one incision through the umbilicus, and without conversion to a standard laparoscopic approach. Mean operative time was 120.1 ± 34.7 min. Tumor laterality and patient body mass index did not affect surgical morbidity. The initial 15 patients had a significantly longer mean pneumoperitoneum time (95.8 ± 37.5 min) than the last 15 patients (70.5 ± 18.7 min). Only one postoperative complication was observed (postoperative hematoma). Conclusions: A transumbilical approach for laparo‐endoscopic single‐site adrenalectomy is safe and feasible, and it results in superior cosmesis. Improvements in surgical devices might facilitate further development of this approach.  相似文献   
98.
Spontaneous perforation of a choledochal cyst with ensuing pseudocyst formation is a very rare complication. We report the development of a pseudocyst adjacent to a choledochal cyst in a very low-birth-weight infant at 2 months of age. Elective excision of the choledochal cyst and biliary tract reconstruction were successfully performed 2 months later when the infant weighed 3 kg. Delayed primary repair may be a viable alternative treatment for low-birth-weight infants with choledochal cysts.  相似文献   
99.

Background

The clinical course of pT3 upper tract urothelial carcinoma (UTUC) is highly variable.

Objectives

The aim of the current study was to validate the clinical and prognostic importance of pT3 subclassification in the renal pelvicalyceal system in a large international cohort of patients.

Design, setting, and participants

From a multi-institutional international database, 858 renal pelvicalyceal tumors treated with radical nephroureterectomy (RNU) were systematically reevaluated by genitourinary pathologists. Category pT3 pelvic tumors were categorized as pT3a (infiltration of the renal parenchyma on a microscopic level only) versus pT3b (macroscopic infiltration of the renal parenchyma and/or infiltration of peripelvic adipose tissue).

Intervention

RNU.

Measurements

Associations of pT3 subclassifications with clinicopathologic features were assessed with the chi-square test. Prognostic impact was assessed with the log-rank test and multivariable Cox regression analyses.

Results and limitations

Of 858 patients with renal pelvicalyceal tumors, 266 (31%) had pT3 disease. Of these, 146 (54.9%) were classified as pT3a and 120 (45.1%) as pT3b. Compared with pT3a, pT3b cancers were associated with higher tumor grade, nodal disease, and tumor necrosis. Ten-year recurrence-free (pT3a 58% vs pT3b 38%; p < 0.001) and cancer-specific (pT3a 60% vs pT3b 39%; p = 0.002) survival rates were lower for patients with pT3b disease. In multivariable analyses, classification pT3b was an independent predictor of both disease recurrence (hazard ratio [HR]: 1.8, p = 0.003) and cancer-specific mortality (HR: 1.7; p = 0.02). The major limitation is the retrospective character of the study.

Conclusions

Subclassification of pT3 renal pelvicalyceal UTUC helps identify patients who are at increased risk of disease progression and cancer-related death. Further research may help assess the value of subclassification and its inclusion in future editions of the American Joint Committee on Cancer–International Union Against Cancer TNM classification system.  相似文献   
100.
PurposeCongenital tracheal stenosis is a rare condition and can be difficult to manage. One source of difficulty is postoperative tracheomalacia requiring long-term tracheal stenting. To prevent symptomatic postoperative tracheomalacia, we have been adding aortopexy to tracheal reconstruction since 2008. The aim of this study was to evaluate efficacy of aortopexy for preventing postoperative tracheomalacia after reconstruction of congenital tracheal stenosis.MethodsRetrospective chart review was conducted. From October 2003 to March 2011, 24 had tracheal reconstruction without aortopexy (group A) and 8 with aortopexy (group B). Statistical analysis was performed using Fisher's Exact test.ResultsOne had anastomotic leakage in group A, and 1, in group B (P = .44). Eleven patients required tracheostomy because of postoperative tracheomalacia confirmed by postoperative bronchoscopy in group A vs none in group B (P = .029).ConclusionsWe found that aortopexy with tracheal reconstruction reduced the need for postoperative tracheostomy in this patient group. Although there is a potential risk of anastomotic leakage because of the suspension suture on the anterior tracheal wall to aorta, we did not detect an increased incidence after aortopexy. Thus, aortic suspension may be a useful adjunct to prevent symptoms of tracheomalacia in these patients.  相似文献   
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