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51.
A wide spectrum of pulmonary complications occurs in patients with pneumoconiosis. Those complications include chronic obstructive pulmonary disease, hemoptysis, pneumothorax, pleural disease, tuberculosis, autoimmune disease, anthracofibrosis, chronic interstitial pneumonia, and malignancy. Generally, imaging workup starts with plain chest radiography. However, sometimes, plain radiography has limited role in the diagnosis of pulmonary complications of pneumoconiosis because of overlapping pneumoconiotic infiltration. Computed tomography (CT), ultrasonography (US), and magnetic resonance imaging (MRI) are potentially helpful for the detection of pulmonary complications in patients with pneumoconiosis. CT, with its excellent contrast resolution, is more sensitive and specific method than plain radiograph in the evaluation of pulmonary abnormalities. CT is useful in detecting lung parenchymal abnormalities caused by infection, anthracofibrosis, and chronic interstitial pneumonia. Also, CT is valuable in distinguishing localized pneumothorax from bullae and aiding the identification of multiloculated effusions. US can be used in detection of complicated pleural effusions and guidance of the thoracentesis procedure. MRI is useful for differentiating between progressive massive fibrosis and lung cancer.  相似文献   
52.

Objective

To cross-validate liver stiffness (LS) measured on shear wave elastography (SWE) and on magnetic resonance elastography (MRE) in the same individuals.

Materials and Methods

We included 94 liver transplantation (LT) recipients and 114 liver donors who underwent either MRE or SWE before surgery or biopsy. We determined the technical success rates and the incidence of unreliable LS measurements (LSM) of SWE and MRE. Among the 69 patients who underwent both MRE and SWE, the median and coefficient of variation (CV) of the LSM from each examination were compared and correlated. Areas under the receiver operating characteristic curve in both examinations were calculated in order to exclude the presence of hepatic fibrosis (HF).

Results

The technical success rates of MRE and SWE were 96.4% and 92.2%, respectively (p = 0.17), and all of the technical failures occurred in LT recipients. SWE showed 13.1% unreliable LSM, whereas MRE showed no such case (p < 0.05). There was moderate correlation in the LSM in both examinations (r = 0.67). SWE showed a significantly larger median LSM and CV than MRE. Both examinations showed similar diagnostic performance for excluding HF (Az; 0.989, 1.000, respectively).

Conclusion

MRE and SWE show moderate correlation in their LSMs, although SWE shows higher incidence of unreliable LSMs in cirrhotic liver.  相似文献   
53.

Objective

To evaluate the correlation between stiffness values obtained by shear-wave elastography (SWE) and breast cancer subtypes.

Methods

This was an institutional review board-approved retrospective study with a waiver of informed consent. The stiffness of 337 invasive breast cancers in 337 women was evaluated by SWE and mean stiffness values (kPa) and qualitative colour scores (1–5) of tumours were obtained. The results were analysed according to BI-RADS category, tumour size, grade and tumour subtype (triple-negative [TN], human epidermal growth factor receptor 2 [HER2]-positive, and oestrogen receptor [ER]-positive) using a multiple linear regression analysis.

Results

The mean stiffness values and colour scores were: 146.8 kPa ± 57.0 and 4.1 ± 1.1; 165.8 kPa ± 48.5 and 4.6 ± 0.7 for TN tumours (n = 64), 160.3 kPa ± 56.2 and 4.3 ± 1.0 for HER2-positive tumours (n = 55) and 136.9 kPa ± 57.2 and 4.0 ± 1.1 for ER-positive tumours (n = 218; P < 0.0001). All three breast cancers classified as BI-RADS category 3 on B-mode ultrasound were TN subtype. A multiple linear regression analysis revealed that tumour size, histological grade and tumour subtype were independent factors that influenced the stiffness values.

Conclusion

High stiffness values correlated with aggressive subtypes of breast cancer.

Key points

? Shear-wave elastography is increasingly used to measure the stiffness of breast tumours. ? Triple-negative and HER2-positive tumours showed greater stiffness than ER-positive tumours. ? All breast cancers classified as BI-RADS 3 on B-mode ultrasound were triple-negative subtype. ? Tumour size, histological grade and subtype were independent factors influencing SWE stiffness.  相似文献   
54.
BACKGROUND: Earlier studies have provided evidence for increased production of reactive oxygen species (ROS) and altered nitric oxide (NO) metabolism in diabetes. This study was intended to explore the effect of type I diabetes and its treatment with insulin alone or insulin plus antioxidant-fortified diet on expression of NOS isoforms and ROS interactions with lipids, glucose and NO. METHODS: Rats with streptozotocin-induced diabetes were divided into once-daily insulin (ultralente)-treated, insulin plus antioxidant (vitamin E and vitamin C)-treated and untreated groups. After four weeks, plasma malondialdehyde (MDA) and tissue endothelial (eNOS), neuronal (nNOS) NO synthases, carboxymethyllysine (CML) and nitrotyrosine were determined. RESULTS: The untreated diabetic animals exhibited severe hyperglycemia, elevated blood pressure, increased plasma MDA, high tissue CML and reduced tissue nitrotyrosine denoting enhanced lipid, glucose and protein oxidation but reduced NO oxidation by ROS. This was coupled with significant reduction of eNOS and nNOS expression in renal cortex and eNOS in the left ventricle. Insulin therapy partially lowered blood pressure, tissue CML, plasma glucose and MDA, but significantly raised eNOS expression and nitrotyrosine abundance to supranormal levels. Combined insulin and antioxidant therapies resulted in normalization of blood pressure, plasma MDA, tissue CML and nitrotyrosine without affecting glucose level or NOS expression. CONCLUSION: Oxidative stress in untreated diabetes is associated with down-regulation of NOS isoforms and increased ROS-mediated oxidation of lipid and glucose, but not NO. Amelioration of hyperglycemia with once-daily insulin administration alone results in up-regulation of NOS isoforms, reduction of lipid and glucose oxidation and increased NO oxidation. However, insulin plus antioxidant supplementation can normalize all three parameters.  相似文献   
55.
The purpose was to retrospectively compare two-dimensional (2D) magnetic resonance cholangiography (MRC) including breath-hold single-shot rapid acquisition with relaxation enhancement (RARE) and multislice half-Fourier RARE versus navigator-triggered 3D-RARE MRC in the evaluation of biliary malignancy. MRC findings were evaluated in 31 patients with malignant biliary obstruction, including biliary malignancy, gallbladder carcinoma, and ampullary cancer. Two observers independently reviewed the images to assess the overall image quality, artifacts, ductal conspicuity, extent of disease, diagnostic confidence of tumor extent, and origin of tumor. The results were compared with surgical and histopathologic findings. Studies obtained with 3D-MRC were of significantly higher technical quality than those obtained with 2D-MRC. However, the accuracy between two sequences for classification of tumor showed no statistical significance. There was no significant difference between the Az values of 2D- and 3D-MRC for overall tumor extent in bilateral second order branch, intrapancreatic common bile duct (CBD) involvement (Az = 0.889, 0.881 for 2D and Az = 0.903, 0.864 for 3D). Nor was there a significant difference between two sequences in the assessment of the origin of tumor. Although 3D-MRC has superior image quality over 2D-MRC, 3D-MRC showed no statistically significant difference in accuracy compared with 2D-MRC for evaluating the extent of disease in malignant biliary obstructions.  相似文献   
56.
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   
57.
BACKGROUND: The morbidity and mortality of anastomotic complications after esophagectomy have gradually decreased in recent years. However, swallowing difficulties and reflux continue to burden patients jeopardizing their quality of life. In the present study we performed endoscopic evaluation of the outcomes of esophagogastrostomy by analyzing the presence of anastomotic stenosis and reflux esophagitis. METHODS: A retrospective analysis was carried out on 74 patients who underwent esophagogastrostomy after esophagectomy by one surgeon between January 1995 and December 2004. Fifty-three patients had an endoscopic examination during follow-up (29 +/- 23.6 months, range = 5-111 months). Reflux esophagitis and stenosis at the anastomostic site were analyzed according to the surgical technique used and the location of the esophagogastrostomy. RESULTS: The mean age at the time of repair was 60.3 +/- 8.87 (range = 39-81) years. Cervical anastomosis was performed in 26 patients and intrathoracic anastomosis in 27 patients. No significant statistical difference in the frequency of anastomotic stenosis was observed between the two groups (p = 0.829); reflux esophagitis was noted in three patients in the cervical anastomosis group and in 14 patients in the intrathoracic anastomosis group (p = 0.041). For all patients, 23 received a hand-sewn esophagogastric anastomosis and 30 a circular stapled one. There was no significant statistical difference in anastomotic stenosis (p = 0.689) and reflux esophagitis (p = 0.879) in comparisons between the two groups. CONCLUSION: Cervical anastomosis resulted in a better outcome for esophagogastrostomy by lowering the risk of reflux esophagitis; this outcome might improve the patient's quality of life.  相似文献   
58.
BACKGROUND AND PURPOSE: Clayman and associates first described laparoscopic nephrectomy in 1990. This paper describes the first randomized controlled trial to compare laparoscopic with open surgery for simple and radical nephrectomy. PATIENTS AND METHODS: Between 2001 and 2004, 45 patients requiring simple or radical nephrectomy (tumors as large as 8 cm) were randomized to either open surgery through a loin incision or laparoscopic nephrectomy (transperitoneal). Outcome measures included operative time, complications, hospital stay, pain scores, time to return to normal activities, and quality of life scores (EuroQol). RESULTS: The mean operative time was 105 minutes in the laparoscopic group and 93 minutes in the open-surgery group (P = 0.4). Blood loss, complications, and the mortality rate were similar in the two groups, as was the hospital stay at a median of 4 days in the laparoscopic group and 5 days in the open group (P = 0.9). Postoperative visual analog pain scores averaged 3.6 in the laparoscopic group compared with 5.4 in the open group (P = 0.02). There was no difference in pain scores at 3 months. Return to normal activities was faster in the laparoscopic group at 42 days v 62 days in the open group (P = 0.04). CONCLUSIONS: Laparoscopic nephrectomy is associated with less postoperative pain and a faster return to normal activities than open nephrectomy.  相似文献   
59.
Sixty-seven patients (78 hips) who were younger than 50 years underwent cementless total hip arthroplasty using a porous-coated acetabular cup, an alumina liner, a 28-mm alumina head, and a proximally porous-coated femoral stem. One patient (1 hip) died and 2 patients (3 hips) were lost to follow-up. The remaining 64 patients (74 hips) were followed for 5 to 6 years. Their mean age at the index operation was 37 years. The mean Harris hip score was 94 points at the time of final follow-up. Four patients (4 hips) had mild thigh pain. All acetabular and femoral components were bone-ingrown, and neither pelvic nor femoral osteolysis was identified. No fracture of the ceramic liner or head was identified. Wear of the ceramic components was undetectable in 27 hips in which measurement was possible.  相似文献   
60.
The treatment of syndesmotic injuries with ankle fractures is controversial. The purpose of this study was to compare the biomechanical properties of open anterior syndesmotic repair with those of screw fixation. Ten matched pairs of human cadaver specimens were subjected to open syndesmotic repair or screw fixation. Each specimen underwent initial intact physiologic loading, consisting of 10 cycles of external torsional loading with a peak torque of 7.5 Nm at 0.05 Hz. Injuries of the anterior inferior tibiofibular ligament, tibiofibular interosseous membrane, and deltoid ligament were applied to each specimen. Postfixation cyclic loading consisted of 50 cycles of combined axial and external rotation loading with peak torques of 750 N and 7.5 Nm at a rate of 0.05 Hz. After postfixation loading, each specimen underwent failure loading by external rotation at 0.25 degrees/second. Failure torque and failure angle were measured. The paired t test and Wilcoxon signed-rank test were used to analyze the data. Mean failure torques were 95.63 Nm in the open anterior syndesmotic repair augmented with suture-tape group and 108.61 Nm in the screw group. Mean failure angles were 34.93 degrees in the open anterior syndesmotic repair augmented with suture-tape group and 43.55 degrees in the screw group. These data were not statistically significantly different between the groups (p= .7682 and .4133, respectively). Open anterior syndesmotic repair augmented with suture tape for ankle syndesmotic injury provides similar torsional strength to that of screw fixation. Therefore, this technique can be considered as an alternative treatment option for syndesmosis injury.  相似文献   
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