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81.
Meniscal injuries are frequently associated with anterior cruciate ligament (ACL) tears. Clinical tests that are useful for detecting meniscal tears may not be valid in this setting. The Thessaly test, a newly described dynamic clinical examination, has been shown to have a very high diagnostic accuracy for detecting meniscal tears. This study evaluates the accuracy of the Thessaly test in patients with combined ACL and meniscus injuries. We examined eighty patients with ACL deficiency for meniscal injuries using the Thessaly test (at 20° of knee flexion), the lateral and medial joint line tenderness tests, and the McMurray test. Examiners were blinded to the MRI report on the conditions of the menisci. All patients underwent arthroscopic ACL reconstruction during which the menisci were evaluated by direct vision and probing. During the Thessaly test, six patients developed severe pain and could not complete the test. Sensitivity, specificity, likelihood ratios and predictive values were calculated for all tests. The Thessaly test had a sensitivity of 79%, specificity of 40%, positive predictive value of 56%, negative predictive value of 66%, positive likelihood ratio of 1.33, negative likelihood ratio of 0.51%, and overall accuracy of 60%. We concluded that the Thesally test has a low specificity in patients with combined ACL and meniscal injuries and can not be recommended as a diagnostic test in this setting.  相似文献   
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Objective

This paper presents the incidence rates of childhood cancers using the data obtained from Golestan population based cancer registry (GPCR) between 2004 and 2006.

Methods

GPCR registers only primary cancers based on standard protocols of the international association of cancer registries (IACR). We collect data on newly diagnosed (incident) cancer cases from all public and private diagnostic and therapeutic centers of the whole province. CanReg-4 software was used for data entry and analysis.

Findings

Totally 5076 cancer cases (all ages) were diagnosed in GPCR between 2004 and 2006. Of these, 139 (2.74 %) were children (aged 0–14 years) with mean (±SD) age of 8.06 (±4.48) years. The age standardized incidence rates for childhood cancer were 119.8 and 78.3 per 1000000 person-years in male and female children, respectively. Leukemia was the most common childhood cancer in Golestan province of Iran. Lymphomas and central nervous system tumors were the second and third ones, respectively.

Conclusion

The incidence rates of childhood cancers were relatively high in Golestan province of Iran. So, controlling of childhood cancers should be mentioned as an important issue in health policy making in this area.  相似文献   
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Background and Aim The relationship between blood group antigens and peptic ulcer disease has been widely evaluated in the past. Data concerning the same association with upper gastrointestinal bleeding are very limited. We aimed to evaluate this association and we thought it was worthwhile to try to determine whether these components take some part in this complication. Methods The study population consisted of 1,098 adults (364 patients and 734 volunteer blood donors as controls). Demographic features, comorbid illnesses, and use of aspirin/nonsteroidal anti-inflammatory drugs (NSAIDs) were recorded. Blood groups were examined by gel centrifugation method. We included only patients with bleeding from peptic ulcer disease and erosive gastropathy. Ulcers were classified by using Forrest’s classification system in terms of rebleeding risk. Helicobacter pylori was examined by histology. Results The gender distribution was similar in both groups. The ABO blood group phenotype distribution in patients and controls (respectively) was as follows: 46.2% versus 34.9% for group O, 32.4% versus 39.5% for group A, 15.7% versus 18.4% for group B, and 5.8% versus 7.2% for group AB. Blood group O was found to have higher frequency in the patient group than in the control group (P = 0.004). Rh positivity was also higher in patients than in controls (P = 0.007). H. pylori positivity was similar between blood groups among patients. The rebleeding and mortality rates between blood groups were also similar. Conclusion ABO blood group O had an important role in patients with upper gastrointestinal bleeding. The impact of blood group on rebleeding and mortality may be a focus for further studies.  相似文献   
84.
Idiopathic portal hypertension (IPH) is characterized by non-cirrhotic presinusoidal intrahepatic portal hypertension. The etiopathogenesis of the disease is poorly understood. Obliteration with microthrombosis of the small portal vein branches may lead to lesions underlying portal hypertension. We aimed to put forward a comprehensive thrombophilic mutation profile in IPH and its probable contribution to pathogenesis. Eleven patients and 12 controls were included. We used the CVD-StripAssay which is based on the reverse-hybridization principle to identify a total of 12 thrombophilic gene mutations: Factor V R506Q, Factor V H1299R, prothrombin G20210A, Factor XIII V34L, beta-Fibrinogen -455 G-A, PAI-1 4G/5G, platelet GPIIIa L33P, MTHFR C677T, MTHFR A1298C, ACE I/D, Apo B R3500Q and Apo E2/E3/E4, respectively. We also evaluated some blood parameters and protein C, protein S, AT-III levels using commercially available assays. IPH patients and controls were similar in respect to gender distribution (P = 1.000). Mean age was 31.2 in patients and 29.1 in controls (P = 0.622). Pica history was present in 54.5% of the patients. Mean protein C and AT-III levels were lower in patients than that of controls (P = 0.002 and 0.001, respectively). Factor XIII V34L, PAI-1, GPIIIa L33P, MTHFR C677T and MTHFR A1298C frequencies of genetic polymorphisms were found to be significantly higher among patients than that of controls. Apolipoprotein E2/E3/E4 analysis showed an inverse relationship with IPH when E2 plus E4 compared with E3. A higher frequency of Beta-Fibrinogen -455G-A mutation was observed in patients, but this difference did not reach a statistical significance. Our data represent the most comprehensive study to date with respect to thrombophilic gene polymorphisms in IPH. The data support a possible pathogenetic role in IPH, at least by some of the prothrombotic mutations. In order to confirm or refuse this proposal, a larger cohort of patients is needed.  相似文献   
85.
Nonsteroidal anti-inflammatory drugs (NSAIDs) cause gastrointestinal (GI) damage primarily due to the inhibition of prostaglandin synthesis in gastric mucosa, which is an important factor in mucosa protection. Platelets are a cardinal feature of vascular repair. A variety of angiogenic stimulators are stored in platelets and are released during clotting at the wound. When there is a defect in any of these functions and/or platelet number, haemostasis is usually impaired and there may be an associated increased risk and severity of bleeding. While the mechanism of mucosal injury and bleeding are well documented with the use of NSAIDs, very little is known about the platelet function abnormalities and their effects on severity of upper GI bleedings. We performed a prospective analysis of 49 patients who had a history of NSAIDs use to investigate the association between the platelet function impairment associated with NSAIDs and severity of upper GI haemorrhages. Thirty-six of 49 patients (73.5%) had deteriorated platelet function. Mean severity score of patients with deteriorated platelet functions was 3.39, and that of patients with normal platelet functions was 2.46. Mean severity score was statistically significantly higher in patients with deteriorated platelet functions. In conclusion, impaired platelet functions associated with NSAIDs may cause more severe upper GI bleeding. Clinicians should be alert for GI complications especially in older patients and in those with a history of ulcer bleeding.  相似文献   
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The microRNAs of Caenorhabditis elegans   总被引:38,自引:0,他引:38       下载免费PDF全文
MicroRNAs (miRNAs) are an abundant class of tiny RNAs thought to regulate the expression of protein-coding genes in plants and animals. In the present study, we describe a computational procedure to identify miRNA genes conserved in more than one genome. Applying this program, known as MiRscan, together with molecular identification and validation methods, we have identified most of the miRNA genes in the nematode Caenorhabditis elegans. The total number of validated miRNA genes stands at 88, with no more than 35 genes remaining to be detected or validated. These 88 miRNA genes represent 48 gene families; 46 of these families (comprising 86 of the 88 genes) are conserved in Caenorhabditis briggsae, and 22 families are conserved in humans. More than a third of the worm miRNAs, including newly identified members of the lin-4 and let-7 gene families, are differentially expressed during larval development, suggesting a role for these miRNAs in mediating larval developmental transitions. Most are present at very high steady-state levels-more than 1000 molecules per cell, with some exceeding 50,000 molecules per cell. Our census of the worm miRNAs and their expression patterns helps define this class of noncoding RNAs, lays the groundwork for functional studies, and provides the tools for more comprehensive analyses of miRNA genes in other species.  相似文献   
89.
Several cases of lung cancer lying within giant bullae have been reported in recent years, such that some authors have considered an association between the two diseases. Giant bulla was detected on the chest X ray and thoracic computed tomography in a 50 year old man. Left lower lobectomy was performed for emphysematous lung destruction. The postoperative histopathological diagnosis was adeno carcinoma arising from the wall of giant bulla. It must be noted that occult cancer may exist at the wall of giant bullae, so annual radiological followup should be applied. On the basis of this experience and review of the literature, it is suggested that physicians should always pay careful attention to the generation and complication of cancer while treating bullous disease in heavy smoking individuals.  相似文献   
90.
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