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131.

Background  

Medical programmes that implement problem-based learning (PBL) face several challenges when introducing this innovative learning method. PBL relies on small group as the foundation of study, and tutors facilitate learning by guiding the process rather than teaching the group. One of the major challenges is the use of strategies to assess students working in small groups. Self-, peer- and tutor-assessment are integral part of PBL tutorials and they're not easy to perform, especially for non experienced students and tutors. The undergraduate PBL medical programme was introduced in 2003, and after two years the curriculum committee decided to evaluate the tutorial assessment in the new program.  相似文献   
132.

Aim

Patients with major depressive disorder (MDD) have been reported to show cognitive impairment in attention, cognition control, and motivation. The prefrontal cortex plays an important role in the pathophysiology of depression. Neurophysiological abnormalities have been examined in MDD patients by several neuroimaging studies. However, the underlying neural mechanism is still unclear. We evaluated brain function during pleasant and unpleasant image‐recall tasks using multichannel near‐infrared spectroscopy (NIRS) in MDD patients.

Methods

The subjects were 25 MDD patients and 25 age‐ and sex‐matched healthy controls. Patients were classified according to DSM‐IV‐TR criteria. We measured the oxygenated hemoglobin concentration change (δoxyHb) in the forehead and temporal lobe during image‐recall task with pleasant (e.g., puppy) and unpleasant (e.g., snake) images using NIRS. To check whether all subjects understood the task, they were asked to draw pictures of both image tasks after NIRS measurement.

Results

The δoxyHb in the healthy group was significantly higher than that in the MDD group in the bilateral frontal region during the unpleasant condition. A significant negative correlation between the Hamilton Rating Scale for Depression score and δoxyHb was observed in the left frontal region during the unpleasant condition.

Conclusion

We suggest that image‐recall tasks related to emotion measured by NIRS might be a visually useful psychophysiological marker to understand the decrease in the frontal lobe function in MDD patients. In particular, we suggest that the decrease in δoxyHb in the left frontal lobe is related to the severity of depression.  相似文献   
133.
134.
OBJECTIVES: The main aim of this study was to reach consensus between students, faculty and general practice teachers on the educational objectives and requirements of the clerkship in general practice. METHOD: The consensus procedure consisted of four steps and all active general practice teachers (n = 116) were asked to participate in the study. RESULTS: We identified 189 educational objectives: 127 complaints (problems, symptoms, syndromes), 29 clinical skills and 37 objectives concerning the theoretical dimensions of general practice. Educational requirements crystallized to 16 essential preconditions of a teaching practice and 35 didactic activities to be performed by the general practice teachers. CONCLUSIONS: These consensus results will be used to structure the medical curriculum and as guidelines for the educational process during the clerkship.   相似文献   
135.
报道4个N-(1-[1-乙氧羰基-3-(对甲)苯氨甲酰基]丙基甘氨酰}-N-取代甘氨酸(XI1~4)和5个1-[1-乙(或甲)氧羰基-3-(对甲)苯氨甲酰基]丙基-4-取代-1,4-哌嗪-2,5-二酮(XII1~5)共9个估计有血管紧张素转化酶抑制活性化合物的合成和鉴定。所有这些化合物及9个相应的酯(X1~9)均未见文献报道。药理初试结果,化合物XII2,XII5,XI4和XII1均有较强降压活性。  相似文献   
136.
Hypercalcemia may be associated with neoplastic disease, either as an epiphenomenon resulting from tumor-produced humoral substances or as a direct consequence of bone involvement. Endoscopic procedures are occasionally performed in this group of patients for both diagnostic and therapeutic purposes. This report reviews the interaction of hypercalcemia and sedative hypnotic drugs and suggests that hypercalcemia might be a risk factor for those patients undergoing endoscopy.  相似文献   
137.
A review of our 402 motility records of patients undergoing evaluation of noncardiac chest pain identified 40 patients with the diagnosis of nutcracker esophagus. Gastroesophageal reflux was found in 13 of 20 patients (65%) who underwent pH studies, and endoscopy detected one patient with erosive esophagitis. Thus, at least 14 (35%) of our nutcracker esophagus patients had evidence of reflux. Twelve of these subjects agreed to enter an open-label therapeutic trial. After 8 wk of intensive antireflux treatment with high doses of ranitidine or omeprazole, repeat 24-h pH studies and endoscopy demonstrated normalization of pH parameters and healing of esophagitis in all patients. Ten (83%) patients obtained significant symptomatic improvement in frequency of pain episodes, number of days with pain, and pain severity. However, repeat manometry showed normalization of motor findings in only two (18%) patients. These observations warrant further placebo-controlled trials. Until more information is available, the results of this study suggest that gastroesophageal reflux should be excluded in patients with noncardiac chest pain and nutcracker esophagus before initiation of smooth muscle relaxant therapy.  相似文献   
138.
Acute puerperal breast abscesses: US-guided drainage   总被引:2,自引:0,他引:2  
  相似文献   
139.
Fifty patients with recurrent post-cholecystectomy pain underwent hepatobiliary scintigraphy. Time-activity curves were generated from regions of interest over the liver, bile duct, duodenum, and bowel. Patients were divided into obstructed and unobstructed groups with endoscopic retrograde cholangiopancreatography criteria. Measurements from the liver, duodenum, and bowel curves contributed little to the analysis. The washout phase of the bile duct curve showed intermittent emptying in both obstructed and unobstructed groups. Less than one-third of peak activity remained in both groups at 90 minutes. Retention fell more rapidly in the later portion of the sequence in patients with obstruction. Quantification was essential, since differences were subtle and could not be appreciated visually. In the absence of hepatocellular disease, the most reliable criterion was the time at which maximal bile duct activity occurred. A cutoff level of 29 minutes or more was used in the diagnosis of obstruction. A sensitivity of 93% with an adequate specificity of 64% and an overall accuracy of 80% was achieved in the prediction of obstruction.  相似文献   
140.
Kloiber  R; Molnar  CP; Barnes  M 《Radiology》1987,163(3):719-723
Ten patients with disseminated bone metastases, nine from prostatic and one from renal cell carcinoma, were treated with intravenous strontium-89. Half the patients experienced significant improvement in pain control and increased general well-being for an average of 14 weeks. Sequential radiophosphate bone scanning showed decreased activity in lesions present at the time of therapy, with subsequent remineralization of the metastases on radiographs. Some patients showed simultaneous reduction in alkaline and acid phosphatase levels. These objective findings prove a physiologic basis for the clinical improvement. Treatments, however, did not prevent progression at initially uninvolved sites, particularly in the extremities.  相似文献   
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