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1.
OBJECTIVES: Local anaesthetic infiltration into the carotid sinus during carotid endarterectomy (CEA) has been recommended to minimise blood pressure fluctuations but its use remains controversial. The aim of this meta-analysis was to determine whether intra-operative administration of local anaesthetic reduces the incidence of haemodynamic instability following CEA. MATERIALS AND METHODS: A search of the Medline, Pubmed and Embase databases and the Current Controlled Trials register identified four trials, which met the pre-defined inclusion criteria for data extraction. Pooled odds ratios with 95 per cent confidence intervals (c.i.) for the development of post-operative hypotension and hypertension were calculated using a random-effects model. RESULTS: Outcomes of 432 patients were studied. Local anaesthetic blockade of the carotid sinus was associated with a pooled odds ratio of 1.25 (95 per cent c.i. 0.496 to 3.15); p=0.216) and 1.28 (95 per cent c.i. 0.699 to 2.33; p=0.428) for the development of post-operative hypotension and hypertension respectively. Although none reach significance there was a trend towards increased risk of developing a complication in those patients who received local anaesthetic. CONCLUSIONS: There are insufficient data to determine the role of intra-operative local anaesthetic administration in reducing post-operative blood pressure lability following CEA. Conversely, the possibility of harm cannot be excluded on the basis of the currently available data.  相似文献   
2.
目的 探索LDH实验检测细胞活力的可行性。方法 原代培养骨髓细胞和软骨细胞,用LDH实验测定上述两组细胞的活力,并与镜下活体观察到细胞的生长状况相比较。与目前比较成熟的测定细胞活力的MTS实验的测得的值相比较。结果 LDH实验对上述两组细胞的活力的测定结果与镜下活体观察到的结果相符合。与MTS实验的测得的结果经统计学处理无显著差异。结论 LDH实验可用于细胞活力的直接测定,而对活细胞的生存、繁殖无影响。  相似文献   
3.
K Varty  D Evans    L Kapila 《Gut》1993,34(11):1478-1481
The original diagnostic 24 hour pH monitoring data in 57 children with gastro-oesophageal reflux (GOR) were retrospectively reviewed after a minimum of one year follow up. The tracings of children who responded to medical treatment were compared with those who failed to respond and required a fundoplication. Children with GOR secondary to oesophageal atresia/tracheo-oesophageal fistula and neurological conditions (n = 12) were analysed separately from those with primary GOR (n = 45). Children with primary GOR requiring a fundoplication (n = 9) had increased daytime reflux. The percentage time pH < 4 was the best discriminator (21% v 7%) with a threshold of 18% giving a 92% specificity and a 70% sensitivity. For children with secondary GOR the percentage time pH < 4 at night was significantly higher (29% v 3.7%) in those requiring a fundoplication (n = 5). A threshold of 18% gave an 80% specificity and an 86% sensitivity. These results show that both daytime and night time pH monitoring data can be of prognostic value in different subgroups of children with GOR. A percentage time pH < 4 of greater than 18% was a useful threshold to apply when evaluating the pH monitoring data.  相似文献   
4.
Parathyroid hormone secretion is negatively regulated by a 7- transmembrane domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that activating mutations in this receptor might cause autosomal dominant hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified, in two families with ADHP, heterozygous missense mutations in the Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of 50 normal controls had either mutation. We also identified a de novo, missense Ca(2+)-sensing receptor mutation in a child with severe sporadic hypoparathyroidism. The amino acid substitution in one ADHP family affected the N-terminal, extracellular domain of the receptor. The other mutations involved the transmembrane region. Unlike patients with acquired hypoparathyroidism, patients with these mutations had hypercalciuria even at low serum calcium concentrations. Their greater hypercalciuria presumably reflected activation of Ca(2+)-sensing receptors in kidney cells, where the receptor negatively regulates calcium reabsorption. This augmented hypercalciuria increases the risk of renal complications and thus has implications for the choice of therapy.   相似文献   
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6.
Tuberculosis of the middle ear it a rare disease. Due to change in the typical clinical pattern and decrease in incidence, there is a delayed or missed diagnosis and can lead to increased morbidity. We pretent 5 cases of Tuberculous Otitis Media treated over a period of 2 years, highlighting the fact that it must be considered as a differential diagnosis of persistent suppurative otitis media.  相似文献   
7.
In the present study we have examined the effect of varying three prepulse parameters (prepulse intensity, prepulse duration, prepulse-pulse interval) on the level of prepulse inhibition (PPI) in Lister hooded, Wistar and Sprague-Dawley rats. The results indicate that each strain showed subtle differences in sensitivity to the prepulse. For instance, Sprague-Dawley and Lister hooded rats showed PPI to prepulses of lower saliency compared to Wistar rats. Optimal prepulse parameters were selected for each strain to examine the effects of apomorphine and phencyclidine on PPI. Further inter-strain differences were noted; apomorphine (0.1-1 mg/kg) increased startle amplitude in Lister hooded and Sprague-Dawley, but not Wistar rats. PPI was attenuated in each strain by apomorphine pretreatment. In a final series of experiments, phencyclidine disrupted PPI in each strain, although with greater potency in the Lister hooded rats. A marked behavioural syndrome was seen at phencyclidine doses that disrupted PPI. It is concluded that rat strain and prepulse parameters are important variables in studying drug effects on PPI.  相似文献   
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9.
Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic hydrocarbon, is the most potent carcinogen ever tested in mouse skin and rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction, tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in strain A/J mouse lung. Groups of mice received a single i.p. injection of 0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment, DNA adducts were measured at times between 1 and 28 days, while tumors were counted at 250 days and analyzed for the occurrence of point mutations in codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung induced six major and four minor DNA adducts. Maximal levels of adduction occurred between 5 and 10 days after injection followed by a gradual decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti- and syn-11,12- dihydroxy-13,14-epoxy- 11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed by cochromatography. The major adduct was identified as a product of the reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced significant numbers of lung adenomas in a dose- dependent manner, with the highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based on the administered dose, DB[a,l]P was more active than other environmental carcinogens including benzo[a]pyrene. As a function of time-integrated DNA adduct levels, DB[a,l]P induced lung adenomas with about the same potency as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar in carcinogenic potency to other PAHs in the strain A/J mouse lung model. Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors revealed the predominant mutations to be G-->T transversions in the first base of codon 12, A-->G transitions in the second base of codon 12, and A-->T transversions in the second or third base of codon 61, concordant with the DNA adduct profile.   相似文献   
10.
Twenty-one patients had a concurrent splenectomy with resection of colorectal cancer between 1970 and 1988. These were matched individually with disease control patients based on age, sex, site of tumor, Dukes stage, tumor differentiation, and date of the operation. Significantly more patients in the splenectomy group (n=11) developed postoperative infective complications than in the control group (n=4) (McNemar test: P =0.03). Five-year overall actuarial survival was 45 percent in the former group and 59 percent in the latter (log rank test: chi-squared=1.07;P =0.24). Similarly, five-year disease-free survival in 17 patients with Dukes B and C cancers who had curative resections did not differ between the groups (log rank test: chi-squared=0.08;P > 0.25). These results suggest that splenectomy with resection of colorectal cancer increases the risk of postoperative sepsis and does not influence long-term survival. The infrequency of concurrent splenectomy at resection of colorectal cancer may not overcome Type II error.  相似文献   
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