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991.
992.
Buccoadhesive controlled-release systems for the delivery of morphine sulfate were prepared by compression of hydroxypropyl methylcellulose (HPMC) with carbomer (CP), which served as the bioactive adhesive compound. The release behavior of systems containing 30 mg of morphine sulfate and various amounts of the two polymers was found to be non-Fickian. The adhesion force was significantly affected by the mixing ratio of HPMC and CP in the tablet, and the weakest adhesion force was observed at a ratio of 1:1 (HPMC:CP). Interpolymer complex formation was confirmed between HPMC and CP in acidic medium by turbidity, viscosity, and FT-IR measurements. The amount absorbed (percentage of the drug loaded) of the controlled-release buccoadhesive tablets in six healthy volunteers and was 30 ± 5%.  相似文献   
993.
Does sodium nitroprusside reduce lung injury under cardiopulmonary bypass?   总被引:4,自引:0,他引:4  
Objective: We hypothesized that direct pulmonary arterial infusion of sodium nitroprusside (SNP) would ameliorate lung injury under cardiopulmonary bypass. Methods: Experiments were performed on 12 adult mongrel dogs of both sexes weighing 20–28 kg. The animals were randomly divided into two groups of six animals each. All animals were subjected to total cardiopulmonary bypass (CPB) and moderate hypothermia (28°C core temperature). During total CPB, the aorta was clamped together with the pulmonary artery to prevent any antegrade flow to the lungs. After cardioplegic arrest for 120 min, the animals were rewarmed, weaned from CPB, and their condition stabilized for another 90 min. After the release of the aortic cross-clamp, the dogs received either a 5% glucose solution as a placebo (group I) or SNP (0.5 μg/kg per min) (group II), both infused into the pulmonary arterial line. The infusion was stopped after 60 min. To measure lung tissue malondialdehyde (MDA), water content and polymorphonuclear leukocytes count, lung tissue samples were taken before CPB and after weaning from CPB. In addition, alveolar-arterial oxygen difference (AaDO2) for tissue oxygenation was calculated by obtaining arterial blood gas samples. Results: Values of MDA before CPB of 42.0±5.3 nmol/g of tissue rose to 67.6±5.7 nmol/g of tissue after weaning from CPB in group I (P=0.028). In group II MDA values also increased from 43.1±4.3 to 52.4±5.7 nmol MDA/g of tissue after weaning from CPB (P=0.046). The MDA increase in group II after CPB was found to be significantly lower than that for group I (P=0.004). The wet-to-dry lung weight ratio in the sodium nitroprusside group was 5.1±0.2, significantly lower than in the control group (6.8±0.4), (P=0.01). AaDO2 increased significantly in group I (P=0.028). There was no statistically significant difference (P=0.065) between groups I and II. During histopathological examination it was observed that neutrophil counts in the lung parenchyma rose significantly after CPB in both groups. The increase in group I was significantly larger than that in group II (P<0.001). Conclusions: The results represented in our study indicate that pulmonary arterial infusion of sodium nitroprusside during reperfusion can reduce lung injury under cardiopulmonary bypass.  相似文献   
994.
BACKGROUND/AIMS: Hydatid acute pancreatitis is a rare condition, mostly reported as case presentations. METHODS: A series of eight patients with hydatid acute pancreatitis, referred between January 1990 and January 2003, are reported. All patients presented acute pancreatitis confirmed with clinical presentation, radiologic examination and laboratory findings. All patients had elevated levels of blood amylase value (more than 500 U/L). Five patients (62%) had high bilirubin levels (2.1 to 3.4 mg/dl) during the initial hospitalization. Computed tomography findings revealed acute pancreatitis in four patients; two had associated pseudocyst formation. RESULTS: Endoscopic retrograde cholangiopancreatography was performed on all patients and revealed hydatid cystic material in the common bile duct secondary to cystobiliary rupture in all patients. All patients underwent endoscopic sphincterotomy that was performed after dilatation with extractor balloon, and hydatid material was removed in all. Six patients were operated on after the initial episode subsided. Drainage of the cyst, appropriate cavity management and T-tube drainage of the common bile duct was employed in all patients to control bile leakage after the operation. Scolices and hydatid membrane were detected during common bile duct exploration in all patients due to presentation of cystobiliary rupture. There was no mortality. Postoperative pulmonary infection and wound infection were encountered in one patient each. During two to 13 years' follow-up, one patient developed recurrent hydatid disease. Recurrent pancreatitis did not occur. CONCLUSIONS: Hydatid acute pancreatitis is a rare condition. However, it should be remembered in patients with abdominal pain, especially in endemic areas.  相似文献   
995.
996.
Abdominal cocoon is a rare cause of intestinal obstruction. The abdominal cocoon is probably a developmental abnormality, largely asymptomatic, and is found incidentally at laparotomy or autopsy. Pre-operative diagnosis cannot be often made correctly. This rare entity of intestinal obstruction has been described in the whole literature as a thick fibrotic sac covering the small bowel partially or completely. The etiology of abdominal cocoon is unknown and most often it is found in adolescent girls from tropical or subtropical countries. Complete recovery is generally expected after the removal of the membrane surgically. This paper reports a male patient who has had intestinal obstruction symptoms and has per-operatively been diagnosed as abdominal cocoon.  相似文献   
997.
Laryngotracheal foreign bodies, although less common than bronchial foreign bodies, are potentially more dangerous. We report a 10-year-old girl with Down syndrome with asthma bronchiale symptoms, which was later found to be the result of a thin bone lamella impacted in her larynx. There was no clear history of foreign body aspiration. She was treated with the initial diagnosis of asthma bronchiale. It took a month before the final diagnosis was made. The foreign body was removed via direct laryngoscopy. It was a white and thin bone lamella with sharp edges, measuring 28 x 19 x 2 mm. We thought the case was worth presenting because of its rare location, the size of the foreign body, and the long duration before the final diagnosis was made.  相似文献   
998.
For many years it has been known that the sensitivity of bone scanning to the presence of destructive bony lesions favors its use in screening for bone metastases and osteomyelitis. More recently bone scanning has been routinely employed in evaluating benign skeletal pathology that may be the cause of low back pain. Bone scanning can play an important part in (1) identifying the cause of pain, (2) clarifying the significance of radiographic findings, and (3) evaluating the results of spinal surgery. This expansion of the role of nuclear medicine in diagnosing and managing low back pain is based in part upon novel diagnostic applications of 99mTc-methylene diphosphonate, a radiopharmaceutical that has been available for over 15 years. Equally important for this development, however, has been the recent availability of SPECT, a tomographic imaging technique that can be used to display the spine in a series of 6- to 8-mm thick sections. Slightly more than one-half of newly purchased gamma cameras are rotating systems suitable for bone SPECT studies. Thus, many community hospitals can now perform state-of-the-art bone scans for low back pain.  相似文献   
999.

The aim of this study was to present a case of disruption of the blood-brain barrier during the coronary and lower extremity angiographies with radiological and clinical findings. This condition was secondary to intraarterial use of a nonionic, monomeric contrast medium. A total of 450 cc contrast media was used. Computed tomography examination showed contrast enhancement of the right occipital and frontoparietal cortical regions, which returned to normal one day after. The patient also fully recovered from the neurological symptoms within 24 h. We discussed the possible mechanism for blood-brain barrier disruption in this case.

  相似文献   
1000.
This report describes a case of multi-focal histiocytosis X of bone in two adjacent vertebrae that caused a spinal cord compression. This case was treated radically with combined surgery and postoperative radiotherapy (RT).  相似文献   
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