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51.
Summary The cortical projections of the brain stem were investigated in detail in the cat by means of the horseradish peroxidase (HRP) retrograde axonal transport. Most of the cells providing ascending fibers to the neocortex were located in the pons (locus coeruleus and related structures, central gray substance, dorsal tegmental nucleus, raphe nuclei, reticular nuclei); labeled neurons were also identified in the mesencephalon, mainly in the periaqueductal gray and in the nucleus linearis rostralis. These projections, and particularly the pontine fibers, were diffusely distributed throughout the cerebral cortex.The results are compared with the data previously obtained by the use of anterograde and retrograde tracing techniques.  相似文献   
52.
A study of the latency of caprine herpesvirus 1 (CpHV.1) was carried out with four latently infected goats. Three goats were treated with dexamethasone and euthanized after 4 and 6 days. PCR and virus isolation allowed us to detect CpHV.1 only in the third and fourth sacral ganglia of the two animals euthanized 6 days after the start of treatment.  相似文献   
53.
A canine parvovirus mutant is spreading in Italy   总被引:6,自引:0,他引:6       下载免费PDF全文
By antigenic and genetic characterization of canine parvovirus type 2 (CPV-2) strains collected in 2001 and 2002 in Italy, it was possible to observe the spread of viruses with an unusual mutation, Glu-426, affecting a major antigenic epitope of CPV-2. Out of 67 strains analyzed, 49 (73.13%) were characterized as CPV-2a, 6 (8.95%) were characterized as CPV-2b, and 12 (17.91%) were characterized as the Glu-426 mutant.  相似文献   
54.
The effects of chronic addiction to, and withdrawal from, opiates on sleep have been described in experimental animals, in human adults and infants born to addicted mothers. These sleep alterations are seen through the first weeks of life. Thirteen maternally addicted babies were studied. Sleep samples were recorded and scored within a few days following birth and repeated 4 or 5 weeks later after recovery from the abstinence syndrome. A significant decrease in quiet sleep and increase of active sleep were found. The same alterations, although less marked, were observed in a follow up recording performed during the second month of life. Sleep alterations in addicted newborns could be related to central nervous system (CNS) distress caused by withdrawal. The authors however propose a perturbation of endogenous opiates subsequent to fetal addiction as a cause of sleep alterations.  相似文献   
55.
Sixty patients underwent intraarterial DSA with injection into the celiac artery for evaluation of various hepatic, pancreatic, and splenic lesions. Twenty of these patients also underwent conventional arteriography for comparison. Excellent images during the early arterial phase (free of bone superimposition and artifacts) were obtained with DSA. The late arterial and parenchymal phases of the examination were less definitive when compared with conventional angiography. The venous phases of the liver studies were good and compared favorably in contrast and resolution to conventional methods. In the late venous phase, good images of the portal system were obtained using a small amount of contrast medium. Respiratory movements and artifacts were overcome with postprocessing. Most of the studies were performed using the 12-inch mode of the image intensifier, which represents the best choice between the size of the field examined and the spatial resolution of the system. We believe that DSA is a suitable substitute for conventional angiography in most patients in whom celiac trunk angiography would be used.  相似文献   
56.
Two fragments, S66 and S55, of the S glycoprotein of the newly identified canine coronavirus type I (CCoV type I), were expressed in a procariotic system. The purified recombinant proteins of 350 and 366 amino acids in length, respectively, were employed to develop an enzyme-linked immunosorbent assay (ELISA) for the detection of CCoV type I antibodies in dog sera. Four canine sera-positive for CCoV type II, four sera-positive for CCoV type I and 10 negative control sera were examined. Only the sera-positive for CCoV type I strongly reacted with both the proteins, whereas the sera-positive for CCoV type II showed low reactivity in the ELISA test. As CCoV type I seems to be not cultivable in cell cultures, the recombinant fragments of the S protein represent a unique method to study, preliminarily, the immunological and the pathogenetic characteristics of this new virus.  相似文献   
57.
Video-assisted thoracic surgery lobectomy for stage I lung cancer   总被引:4,自引:0,他引:4  
BACKGROUND: The technique, safety, and oncologic efficacy of video-assisted thoracic surgery (VATS) lobectomy are controversial. Issues include operative time, lymph node yield, conversion to thoracotomy, resource utilization, recurrence, complications, and survival. METHODS: From January 1995 to December 2001, 179 patients underwent VATS lobectomy for preoperative stage I lung cancer (T1N0, 118 patients; T2N0, 61 patients). Mean age was 64.34 years (range, 38 to 87); 91 were female and 88 were male. Contraindications to VATS lobectomy included any suggestion of hilar, endobronchial, or central lesions. Video-assisted thoracic surgery lobectomy was performed using three ports, partial anatomic hilar dissection, and mediastinal node dissection. RESULTS: Distribution of lobectomies was as follows: left upper lobe, 50 patients; left lower lobe, 27 patients; right upper lobe, 33 patients; right upper and right middle lobe, 29 patients; right middle lobe, 9 patients; right lower lobe, 30 patients; right middle lobe and right lower lobe, 1 patient. Mean operative time was 75 +/- 6 minutes. Mean lymph node yield was 11 +/- 5 nodes. Pathologic upstaging was noted in 14 of the 179 patients (7.8%). Mean hospitalization was 4.1 days (range, 2 days to 4 months). There were no conversions to thoracotomy and there was 1 death (1 of 179, 0.05%). Complications included air leak in 24 of 179 (13.4%), subcutaneous emphysema in 4 of 179 (2.2%), pneumonia in 10 of 179 (5.6%), wound infection in 5 of 179 (2.8%), respiratory failure in 3 of 179 (1.7%), pulmonary embolism in 2 of 179 (1.1%), and myocardial infarction in 1 of 179 (0.5%). At a mean follow-up of 37 months, local recurrence rate was 0.013 per person per year. Actuarial recurrence-free survival was 88% and 85% at 36 and 60 months respectively. CONCLUSIONS: For carefully selected patients VATS lobectomy for early stage lung cancer is a safe and effective strategy. Long-term follow-up is required to fully evaluate recurrence and survival.  相似文献   
58.
BACKGROUND: The treatment of primary spontaneous pneumothorax in young adults has been controversial. Conventional treatment consisting of chest tube thoracostomy may be associated with morbidity at the time of tube insertion, prolonged hospitalization, and interval operation in many patients. As spontaneous pneumothorax in young adults is usually associated with apical blebs, we hypothesized that video-assisted thoracic surgical (VATS) resection of the blebs at the time of the first pneumothorax may be an effective treatment associated with low morbidity and short hospital stays. METHODS: From July 1992 to February 2001, 156 young adults were treated for spontaneous pneumothorax. Within 12 hours of presentation to the emergency department patients underwent semielective VATS with bleb resection and pleuradesis. During follow-up patients were observed for recurrent pneumothorax. RESULTS: There were 69 men (44%) and 87 women (56%). The median age was 19 years old (range 14 to 38 years old). Patients were predominantly tall and thin. Patients were mildly symptomatic at the time of presentation. Apical blebs were seen in all patients and the presence of blebs was confirmed in the pathologic specimen. In 23 patients bleeding was associated with bleb rupture. There were no postoperative air leaks. The mean hospital stay was 2.4 +/- 0.5 days. Follow-up ranged from 2 to 96 months (median 62 months). There were no recurrences on the index side. CONCLUSIONS: VATS resection of apical blebs is associated with low morbidity and short hospitalization and provides an attractive alternative to the conventional treatment of initial tube thoracostomy and possible interval repeat thoracostomy or operation. VATS may be an effective first line treatment for spontaneous pneumothorax in young adults. Due to the pathophysiology of this disease, patients should be closely followed for the occurrence of pneumothorax on the contralateral side.  相似文献   
59.
Digital subtraction angiography (DSA) using a 41-cm (16-in.) image intensifier was performed in 144 patients with peripheral vascular insufficiency. In most cases the entire peripheral vascular bed from the renal arteries to the popliteal trifurcation was demonstrated with four intravenous injections and four exposed fields: (a) aorto-iliac, (b) ilio-femoral, (c) femoro-popliteal, and (d) popliteo-tibial. In 90% of cases the procedure was diagnostic in all regions studied, while in 10 it was nondiagnostic in one or more regions for various reasons (myocardial insufficiency, inadequate contrast bolus, or technical failure). Most failures involved the distal arteries. In spite of some limitations, intravenous DSA using a large-field image intensifier may replace conventional angiography in routine preoperative evaluation of peripheral vascular disease, with intra-arterial injections being performed when the intravenous technique is nondiagnostic.  相似文献   
60.
The authors present the results achieved with angiographic evaluation of 34 patients suffering from extremity injuries. In spite of the improvements of various diagnostic techniques, especially ultrasound studies, they believe that emergency arteriography is the only way to obtain an ultimate answer in vascular traumas caused by extremity injuries.  相似文献   
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