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1.

Background

In the emergency department, rib fractures are a common finding in patients who sustain chest trauma. Rib fractures may be a sign of significant, underlying pathology, especially in the elderly patients where rib fractures are associated with significant morbidity and mortality. To date, no studies have evaluated the ability of ultrasound to detect rib fractures using cadaver models and subsequently use this model as a teaching tool.

Objectives

The purpose of this study was to determine if it is possible to generate rib fractures on cadaver models which could be accurately identified using ultrasound.

Methods

This was a cross-sectional study performed during one session at a cadaver lab. A single hemithorax from four adult cadavers were used as models. Single rib fractures on each of rib five through eight were created. Four subjects, blinded to the normal versus fractured ribs, were asked to identify the presence of a fracture on each rib.

Results

A total of 8 of 16 potential ribs had fractured induced by study staff. Mean accuracy was 55% for all subjects. The overall sensitivity and specificity for detecting rib fractures was 50% (CI: 31.89–68.11) and 59.38% (CI: 35.69–73.55) respectively. The overall PPV and NPV was 55.17% and 54.29% respectively.

Conclusions

In this pilot study, subjects were not able to detect induced rib fractures using ultrasound on cadaver models. The use of this model as a teaching tool in the detection of rib fractures requires further investigation.  相似文献   
2.
Neonatal pain management is a challenge for the clinician. Research is just beginning to uncover the neonates' capability of expression of pain, explore pharmacologic management strategies, and identify the spectrum of intrusions that may precipitate pain or distress in the critically ill neonate. This article reviews the neonatal biologic, behavioral, and physiologic responses to pain and describes recommendations for clinical management and decision-making.  相似文献   
3.
Defecography in multiple sclerosis patients with severe constipation   总被引:3,自引:0,他引:3  
Gill  KP; Chia  YW; Henry  MM; Shorvon  PJ 《Radiology》1994,191(2):553
  相似文献   
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Iatrogenic injury to the aorta or its major branches during nephrectomy for Wilms' tumor in children is rarely reported but may be more common than is currently acknowledged. We identified four patients with ligation of the superior mesenteric artery (SMA) that occurred during nephrectomy for nephroblastoma and another child in whom SMA thrombosis developed postoperatively. All of the tumors were on the left side. Interruption of the SMA was recognized intraoperatively in all four children, and primary repair was done. In three patients, appearance of the bowel remained normal before repair of the injury. Three of the arteries were repaired by primary reanastomosis, and one was joined with an interpositioned hypogastric artery graft. None of these patients had gastrointestinal complications postoperatively. In the fifth patient, SMA thrombosis developed after repair of an aortic tear during nephrectomy. This patient required subsequent small bowel resection for bowel infarction and died in the perioperative period. Every surgeon treating children with Wilms' tumor should be aware of the possibly distorted vascular anatomy and take precautions to avoid such a significant injury. Attempts at early ligation of the vessels may not be justified until the renal vasculature is clearly identified.  相似文献   
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Summary: The involvement of the IgA immune system and complement components in IgA glomerulonephritis (IgAGN) has prompted the use of immunosuppressive drugs in therapy, but none has so far been shown to alter the natural course of the disease. Because most patients with IgAGN present during the chronic phase of their illness, at the time when the initiating immune events may no longer be active, nonimmune therapy which targets the common pathway of progressive renal injury is likely to be more useful. There is increasing evidence that angiotensin-converting enzyme inhibitors (ACEI) reduce proteinuria and renal injury in patients with IgAGN, and this effect may be observed in both normotensive and hypertensive patients. Yet to be determined is whether this effect is specific for ACEI and whatever other effective antihypertensive drugs may achieve a similar result. Fish oil has recently been shown to retard the progression of renal failure in patients with aggressive IgAGN, but a narrow therapeutic window appears to exist for this form of treatment. Antiplatelet agents on their own appear to be ineffective but in combination with anticoagulation (low dose warfarin) have been shown to have an antiproteinuric effect and may preserve renal function in patients with progressive disease. Future directions of non-immune therapy of IgAGN include evaluation of the renoprotective effect of angiotensin II receptor antagonists, free-radical scavengers and antilipid drugs. More work should also be done to identify factors which put the patients at risk of developing progressive disease and which predict therapeutic response, as has been done recently with the identification of the deletion polymorphism of the angiotensin-converting enzyme gene as a marker of progressive disease and therapeutic response to ACEI in patients with IgAGN.  相似文献   
8.
Ultrastructure of sialadenoma papilliferum   总被引:1,自引:0,他引:1  
Sialadenoma papilliferum is a rare tumor of salivary gland origin and has been reported in the parotid and minor salivary glands of the oral cavity. This tumor is morphologically similar to the papillary syringoadenoma of the sweat gland. We report the clinical and morphologic features of five cases and review the literature. Ultrastructural examination of case 1 revealed the predominant cell type to be an oncocytic cell. These cells contained numerous mitochondria, exhibited parallel filaments within the cell cytoplasm, and were attached by desmosomes. The neoplastic cells appear to exhibit characteristic features of various cell types of the salivary gland duct apparatus.  相似文献   
9.
An elderly woman with Streptococcus pneumoniae meningitis relatively resistant (minimum inhibitory concentration, [MIC] = 0.12 micrograms/mL) to penicillin is reported. The occurrence of penicillin-resistant pneumococcal infections is reviewed and management discussed. Because of the importance of recognition of resistant pneumococci, a state-wide clinical laboratory survey was conducted to determine the accuracy of susceptibility testing for this isolate. Of 111 laboratories completing the survey, only 26 performed the 1-microgram oxacillin disk test as recommended by the National Committee for Laboratory Standards (NCCLS). When laboratories were analyzed according to hospital size, the proficiency in performing the proper susceptibility testing was 55% (6 of 11) for hospitals with more than 400 beds versus 3% (2 of 58) for hospitals with fewer than 100 beds (P less than 0.0001 by Fisher's exact test). This contrasts with reported surveys by the College of American Pathologists (CAP), and reasons for this are explored. Guidelines for laboratory testing of S. pneumoniae are reviewed, and additional study of clinical proficiency with attention to laboratory size is recommended.  相似文献   
10.
Usher syndrome is recognized as the most frequent cause of hereditary deaf-blindness. Usher syndrome type I (USH1), the most severe form of the disease, is characterized by profound congenital sensorineural deafness, constant vestibular dysfunction, and retinitis pigmentosa of prepubertal onset. This form is genetically heterogeneous and five loci (USH1A-E) have been mapped thusfar. However, only the gene responsible for USH1 B (which accounts for approximately 75% of USH1 cases) has been characterized. It encodes a long-tailed unconventional myosin, myosin VIIA, with a predicted 2215 amino acid sequence. Primers covering the complete myosin VIIA coding sequence as well as the 3' non coding sequence were designed, allowing direct sequence analysis of each of the 48 coding exons and flanking splice sites in seven patients affected by USH1. Four novel mutations were thereby identified. The possibility should now be considered of a sequence-based prenatal diagnosis in some of the families affected by this very severe form of Usher syndrome.   相似文献   
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