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81.
Cerebral salt wasting: truths,fallacies, theories,and challenges   总被引:6,自引:0,他引:6  
BACKGROUND: The reported prevalence of cerebral salt wasting has increased in the past three decades. A cerebral lesion and a large natriuresis without a known stimulus to excrete so much sodium (Na ) constitute its essential two elements. OBJECTIVES: To review the topic of cerebral salt wasting. There is a diagnostic problem because it is difficult to confirm that a stimulus for the renal excretion of Na is absent. DESIGN: Review article. INTERVENTION: None. MAIN RESULTS: Three fallacies concerning cerebral salt wasting are stressed: first, cerebral salt wasting is a common disorder; second, hyponatremia should be one of its diagnostic features; and third, most patients have a negative balance for Na when the diagnosis of cerebral salt wasting is made. Three causes for the large natriuresis were considered: first, a severe degree of extracellular fluid volume expansion could down-regulate transporters involved in renal Na resorption; second, an adrenergic surge could cause a pressure natriuresis; and third, natriuretic agents might become more potent when the effective extracellular fluid volume is high. CONCLUSIONS: Cerebral salt wasting is probably much less common than the literature suggests. With optimal treatment in the intensive care unit, hyponatremia should not develop.  相似文献   
82.
We report the case of a 38-year old man who developed erythroderma during treatment with teicoplanin for staphylococcal septicaemia. The clinical symptoms, which included high fever, shock and erythroderma, were suggestive of staphylococcal toxic shock. After teicoplanin was withdrawn and replaced by vancomycin the disease followed a favourable course. The reintroduction test was positive. This case illustrates the problems associated with the diagnosis of erythroderma in intensive care patients and confirms that it is possible to prescribe vancomycin in cases with allergic reaction to teicoplanin.  相似文献   
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Penile squamous cell carcinoma shows an ample geographic variation in its prevalence with regions of low (North America, Europe, Japan, and Israel) and high (Africa, Asia, and South America) incidence. However, the geographic variation in the distribution of penile intraepithelial neoplasia is not well established. The aim of the present study was to compare the distribution of in situ and invasive lesions between geographic areas with low (France) and high (Paraguay) penile cancer incidence using a series of consecutive cases. The French series included 86 cases (57 in situ and 29 in situ + invasive squamous cell carcinoma), and the Paraguayan series, 117 cases (31 in situ and 86 in situ + invasive squamous cell carcinoma). Incidence of invasive squamous cell carcinoma in the overall samples was higher in the Paraguayan series (P < .00001). Comparing the Paraguayan and the French series, differentiated penile intraepithelial neoplasia was more prevalent in the former (65.0% versus 19.8%), whereas lesions showing warty and/or basaloid features predominated in the latter (35.0% versus 80.2%) to a significant level (P < .00001). This distinctive pattern of differential distribution was maintained when cases with associated invasive squamous cell carcinoma were excluded. The pattern of distribution of lichen sclerosus was also distinctive, with a significantly higher prevalence in the Paraguayan population when compared with the French series (32.5% versus 12.8%, P = .0015). In summary, there appears to be a distinctive distribution of penile precursor lesions depending on the geographic region in consideration. Penile intraepithelial neoplasia with warty and/or basaloid features predominated in low-incidence areas, whereas differentiated penile intraepithelial neoplasia was more prevalent in endemic regions for penile cancer. Further prospective studies in matched populations and from different geographic regions are needed to further clarify the reasons for this discrepancy.  相似文献   
86.
The effect of short duration and different degrees of distension pressures was investigated by means of immunohistochemistry of the three nitric oxide synthase isoforms in the human saphenous vein conventionally harvested from 20 patients submitted to coronary artery bypass graft. The human saphenous vein distal portion was divided into four segments, each one allocated to a different group. In Group I (control group), the human saphenous vein segment was not exposed to distension pressure. In Groups II, III, and IV, the human saphenous vein segment was exposed to 100, 200, and 300 mmHg of distension pressure, respectively. The distension pressures were applied and maintained with Krebs solution for 15 s. The human saphenous vein of the control group presented endothelial nitric oxide synthase and neuronal nitric oxide synthase in both endothelial and smooth muscle cells, while the inducible nitric oxide synthase appeared predominantly in the medial layer. Neither 100 nor 200 mmHg of pressurization affected the immunostaining of any nitric oxide synthase isoform. However, the human saphenous vein segments exposed to 300 mmHg of distension pressure showed a reduction in endothelial nitric oxide synthase content in the endothelium, but not in the tunica media. This lower endothelial nitric oxide synthase immunostaining in the intimal cells was associated with endothelial denudation. Therefore, we conclude that care should be taken when handling the human saphenous vein since just a few seconds of distension pressure above the normal systemic pressure can be sufficient to disrupt the endothelium reducing the amount of endothelial nitric oxide synthase and impairing the graft quality.  相似文献   
87.
The prevalence of metastatic basal cell carcinoma (MBCC) varies between 0.0028% and 0.55% of all cases. In total, more than 300 MBCC have been reported in the literature. We report the case of a 72 year old lady, who presented in September 2009 with a 10-year history of a progressively growing, giant, facial basal cell carcinoma (BCC). Clinical and imaging evaluations identified large local invasion with bone and meningeal involvement. Treatment consisted of an extensive surgery including left eye exenteration and meningeal resection followed by radiotherapy. A solitary lung metastasis was identified five months after the primary tumor resection. As the lesion remained solitary but had increased in size five months later, the patient finally accepted a surgical resection. A right upper-lobe pneumonectomy was performed and pathologic examination confirmed the metastasis as a MBCC.  相似文献   
88.
The usual way to decide why hyponatremia or hypernatremia has developed and to plan goals for its therapy is to analyze events in electrolyte-free water (EFW) terms. We shall demonstrate that an EFW balance does not supply this information. Rather, one must calculate mass balances for water and sodium plus potassium separately (a tonicity balance) to understand the basis for the change in natremia and the proper goals for its therapy. These points are illustrated with a clinical example.  相似文献   
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Lipospheres carrying timolol (1) were obtained from microemulsions. They had lecithin, palmitic and decanoic acids as the main constituents. The sizes were between 300 and 400 nm and the amount of 1 incorporated varied from 2.7 to 4.8% according to the microemulsion used. Compound 1 was present in the lipospheres mainly as ion pairs in order to increase its lipophilicity. The difference found in the incorporation was principally due to the different lipophilicity of the ion pairs of 1.  相似文献   
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