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51.
A 64-year-old male had an awake right nasal fiber-optic intubation with an endotracheal tube for open reduction and internal fixation of bilateral displaced mandibular fractures. After induction of anesthesia, an 18 Fr nasogastric tube (NGT) was inserted through the left nostril and was secured. The patient required high flow rates to deliver adequate tidal volumes with the ventilator. A chest x-ray done in the postanesthesia care unit revealed a malpositioned NGT in the left lower lobe bronchus, which was immediately removed. The patient was extubated on postoperative day 2. Various traditional methods, such as aspiration of gastric contents, auscultation of gastric insufflations, and chest x-ray are in use to detect or prevent the misplacement of an NGT. These methods can be unreliable or impractical. Use of capnography to detect an improperly placed NGT should be considered in the operating room as a simple, cost-effective method with high sensitivity to prevent possibly serious sequelae of an NGT placed within the bronchial tree.Key words: Nasogastric tube, Misplacement, Oral surgeryPlacement of a nasogastric tube (NGT) preoperatively for decompression of the stomach is common practice to allow drainage of gastrointestinal contents in the case of bowel obstruction, or in other cases when the patient is at risk of aspiration for some other reason. This case report involves a patient who required aspiration precautions via NGT placement for mandibular surgery due to facial trauma; the NGT was later found to be misplaced in the left main stem bronchus as the misplacement was unrecognized intraoperatively. We discuss the necessity of preventing the possible intraoperative and postoperative complications of a misplaced NGT and simple measures to recognize misplacement in patients presenting for similar surgeries.  相似文献   
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Physical examination (PE) is an excellent means of predicting arteriovenous fistula (AVF) dysfunction. Although quick and inexpensive, PE is seldom used as a tool to assess stenosis by general nephrologists, dialysis nurses, and dialysis technicians. Previous studies have demonstrated that PE can be taught to interventional specialists, but the perception remains that it is too complex to be performed by other health care professionals. We hypothesized that the physical exam can be taught to a nonmedical professional, and that, with time, it would be comparable to the physical exam performed by a full‐time interventional specialist. An undergraduate student and an interventional specialist (MD) examined AVF for dysfunction in a tertiary care hospital over a 6‐month period. PE was performed on patients who were suspected of having dialysis access dysfunction and were referred for angiography and intervention (n = 49). Physical exam findings were categorized blindly by each examiner into four categories of lesion location: inflow, outflow, both, or neither. Data were privately recorded and compared to the gold standard of angiographic results. Potential confounding variables, including age, gender, diabetic status, and location of AVF were recorded. Weighted Cohen's kappa value was used as a measurement of the level of agreement beyond chance between the diagnoses made by physical exam and angiography. The full‐time interventional specialist demonstrated correct prediction of lesion location of 89.8% (kappa = 0.850), while the undergraduate student had a correct prediction of 77.6% (kappa = 0.625). The student's performance, however, differed significantly over time. The student correctly predicted the location of the lesion in 6 (42.9%) of the first 14 patients (kappa = 0.082), compared to 32 (91.4%) of the last 35 patients (kappa = 0.855). We suggest that physical exam of AVF can be taught to a nonmedical professional in a short duration of time and the predictive value of the exam can be similar to that of an interventional specialist.  相似文献   
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Background: Streptococcus constellatus and Streptococcus intermedius in subgingival dental plaque biofilms may contribute to forms of periodontitis that resist treatment with conventional mechanical root debridement/surgical procedures and may additionally participate in some extraoral infections. Because systemic antibiotics are often used in these clinical situations, and little is known of the antibiotic susceptibility of subgingival isolates of these two bacterial species, this study determined the in vitro susceptibility to six antibiotics of fresh S. constellatus and S. intermedius clinical isolates from human periodontitis lesions. Methods: A total of 33 S. constellatus and 17 S. intermedius subgingival strains, each recovered from separate patients with severe chronic periodontitis (n = 50) before treatment, were subjected to antibiotic gradient strip susceptibility testing with amoxicillin, azithromycin, clindamycin, ciprofloxacin, and doxycycline on blood‐supplemented Mueller‐Hinton agar and to the inhibitory effects of metronidazole at 16 mg/L in an enriched Brucella blood agar dilution assay. Clinical and Laboratory Standards Institute and European Committee on Antimicrobial Susceptibility Testing interpretative standards were used to assess the results. Results: Clindamycin was the most active antibiotic against S. constellatus (minimum inhibitory concentration at 90% [MIC90] 0.25 mg/L), and amoxicillin was most active against S. intermedius (MIC90 0.125 mg/L). A total of 30% of the S. constellatus and S. intermedius clinical isolates were resistant in vitro to doxycycline, 98% were only intermediate in susceptibility to ciprofloxacin, and 90% were resistant to metronidazole at 16 mg/L. Conclusion: Subgingival S. constellatus and S. intermedius exhibited variable antibiotic susceptibility profiles, potentially complicating empirical selection of periodontitis antibiotic therapy in patients who are species positive.  相似文献   
58.
BACKGROUND  Patients are routinely ill-prepared for the transition from hospital to home. Inadequate communication between Hospitalists and primary care providers can further compromise post-discharge care. Redesigning the discharge process may improve the continuity and the quality of patient care. OBJECTIVES  To evaluate a low-cost intervention designed to promptly reconnect patients to their “medical home” after hospital discharge. DESIGN  Randomized controlled study. Intervention patients received a “user-friendly” Patient Discharge Form, and upon arrival at home, a telephone outreach from a nurse at their primary care site. PARTICIPANTS  A culturally and linguistically diverse group of patients admitted to a small community teaching hospital. MEASUREMENTS  Four undesirable outcomes were measured after hospital discharge: (1) no outpatient follow-up within 21 days; (2) readmission within 31 days; (3) emergency department visit within 31 days; and (4) failure by the primary care provider to complete an outpatient workup recommended by the hospital doctors. Outcomes of the intervention group were compared to concurrent and historical controls. RESULTS  Only 25.5% of intervention patients had 1 or more undesirable outcomes compared to 55.1% of the concurrent and 55.0% of the historical controls. Notably, only 14.9% of the intervention patients failed to follow-up within 21 days compared to 40.8% of the concurrent and 35.0% of the historical controls. Only 11.5% of recommended outpatient workups in the intervention group were incomplete versus 31.3% in the concurrent and 31.0% in the historical controls. CONCLUSIONS  A low-cost discharge–transfer intervention may improve the rates of outpatient follow-up and of completed workups after hospital discharge.  相似文献   
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Ghrelin is the endogenous ligand for the growth hormone secretagogue receptor (GHSR; ghrelin receptor). Since its discovery, accumulating evidence has suggested that ghrelin may play a role in signaling and reversing states of energy insufficiency. For example, ghrelin levels rise following food deprivation, and ghrelin administration stimulates feeding and increases body weight and adiposity. However, recent loss-of-function studies have raised questions regarding the physiological significance of ghrelin in regulating these processes. Here, we present results of a study using a novel GHSR-null mouse model, in which ghrelin administration fails to acutely stimulate food intake or activate arcuate nucleus neurons. We show that when fed a high-fat diet, both female and male GHSR-null mice eat less food, store less of their consumed calories, preferentially utilize fat as an energy substrate, and accumulate less body weight and adiposity than control mice. Similar effects on body weight and adiposity were also observed in female, but not male, GHSR-null mice fed standard chow. GHSR deletion also affected locomotor activity and levels of glycemia. These findings support the hypothesis that ghrelin-responsive pathways are an important component of coordinated body weight control. Moreover, our data suggest that ghrelin signaling is required for development of the full phenotype of diet-induced obesity.  相似文献   
60.
Lung cancer is the leading cause of cancer death in the United States. Despite recent advances in screening protocols, the majority of patients still present with advanced or disseminated disease. Preclinical rodent models provide a unique opportunity to test novel therapeutic drugs for targeting lung cancer. Respiratory-gated MRI is a key tool for quantitatively measuring lung-tumor burden and monitoring the time-course progression of individual tumors in mouse models of primary and metastatic lung cancer. However, quantitative analysis of lung-tumor burden in mice by MRI presents significant challenges. Herein, a method for measuring tumor burden based upon average lung-image intensity is described and validated. The method requires accurate lung segmentation; its efficiency and throughput would be greatly aided by the ability to automatically segment the lungs. A technique for automated lung segmentation in the presence of varying tumor burden levels is presented. The method includes development of a new, two-dimensional parametric model of the mouse lungs and a multi-faceted cost function to optimally fit the model parameters to each image. Results demonstrate a strong correlation (0.93), comparable with that of fully manual expert segmentation, between the automated method's tumor-burden metric and the tumor burden measured by lung weight.  相似文献   
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