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1.
This study was designed to analyse the relationship betweenarterial hypertension and changes in arterial blood flow andvascular wall damage of the lower limbs in hypertensive patientswith various degrees of hypertension. Six hundred and fifty-four hypertensive patients (421 malesand 233 females) aged 35 to 70 years and 88 healthy subjects(63 males and 25 females) aged 39 to 60 years were studied.Strain-gauge plethysmography of the lower limbs was used tocalculate arterial calf blood flow (RF), arterial calf bloodflow after post-ischaemic hyperaemia (PF), basal and minimalvascular resistances (BVR and MVR), time to reach peak flow(tPF), time until 50% reduction of peak flow (tT) and totalrecovery time (tT). In 108 (67 males and 41 females) of the hypertensive patients,a morphological study by echo-Doppler duplex scanning of thepopliteal artery was performed to measure medial-intimal thickeningand popliteal lumen diameter. Our results indicate that regional haemodynamics of the lowerlimbs worsened in hypertensives in comparison with control subjects.In addition, the change in peripheral haemodynamics was relatedto the degree of hypertension. Moreover, medial-intimal thickeningwas significantly (P<0.05) higher in severe hypertensivesthan mild hypertensives. Popliteal lumen diameter was significantly(P<0.05) lower in severe hypertensives than moderate andmild hypertensives. In all these subjects mean blood pressurewas correlated directly (r=0.31; P<0.001) with medial-intimalthickening and inversely (r= – 0.37; P<0.001) withpopliteal lumen diameter. Multiple regression analysis indicatedthat mean blood pressure, age and serum cholesterol were independentlycorrelated to medial-intimal thickening. This relationship wasnot influenced by the diabetic patients and smokers among thegroups. Our results indicate that hypertension impairs peripheral flowand encourages the development of medial-intimal thickening.  相似文献   
2.
A 43-year-old woman with a unilateral cleft lip and palate, presenting a totally edentulous maxilla and mandible with marked maxillomandibular discrepancy, attended the Prosthodontics section of the Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo for treatment. She could not close her mouth and was dissatisfied with her complete dentures. Treatment planning comprised placement of six implants in the maxilla, four in the mandible followed by prostheses installation and orthognathic surgery. The mandibular full arch prosthesis guided the occlusion for orthognathic positioning of the maxilla. The maxillary complete prosthesis was designed to assist the orthognathic surgery with a provisional prosthesis (no metal framework), allowing reverse treatment planning. Maxillary and mandibular realignment was performed. Three months later, a relapse in the position of the maxilla was observed, which was offset with a new maxillary prosthesis. This isa complex interdisciplinary treatment and two-year follow-up is presented and discussed. It should be considered that this type of treatment could also be applied in non-cleft patients.  相似文献   
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Despite all the emphasis laid today on the green economy, occupational health and safety (OHS) issues have still been talked only limitedly, as already noted in previous studies and literature reviews. The Department of Occupational and Environmental Medicine, Epidemiology and Hygiene of the Italian Workers’ Compensation Authority (INAIL) has conducted a survey among some Italian stakeholders, social partners, institutions and “green” businesses to gather their perceptions of the potential effects of green jobs on OHS, particularly in the renewable energy sector. The survey involved a sample of 61 stakeholders in the following categories: institutions (11), trade unions (11), employers’ organizations (13), businesses (11), research (15). Participation in this survey of national stakeholders who have a central role in the development and management of policies on renewable energy and OHS, allowed to analyze in depth the fundamental aspects for a fair transition towards green economy. Also, the good agreement among respondents brought to light quite clearly the main critical points as regards the OHS implications of green work in Italy, and pointed to the principal policies to be adopted to safeguard workers’ health and safety.  相似文献   
4.
International Journal of Paediatric Dentistry 2010; 20: 426–434 Background. The prevalence of molar incisor hypomineralization (MIH) varies considerably around the world; however, few studies have examined MIH in South American countries. Objective. To evaluate the prevalence, severity, and clinical consequences of MIH in Brazilian children residing in rural and urban areas of the municipality of Botelhos, Minas Gerais, Brazil. Methods. Children aged 6 to 12 years (n = 918) with all four‐first permanent molars erupted had these teeth evaluated according to the European Academy of Paediatric Dentistry (EAPD) criteria. The examinations were conducted by two previously trained examiners, and the dental impact caused by MIH was evaluated with the Decayed, Missing and Filled Teeth (DMFT) index (WHO). Results. Molar incisor hypomineralization was present in 19.8% of the 918 children, with a higher prevalence in rural areas. The majority of the defects presented were demarcated opacities without post‐eruptive structural loss, which has been considered as mild defects. Children with MIH had higher DMFT values. Conclusion. Despite the high prevalence of MIH, the severity of the defects was mild. The results indicate a positive association between MIH and the presence of dental caries.  相似文献   
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Nucleotide sequences of the hypervariable segment I of the control region of the mtDNA were determined in 101 individuals: 54 Canary Islanders, 18 North African Berbers, 18 Spanish mainlanders and 11 sub-Saharan Guineans. In spite of the fact that only members of the Fang tribe were analysed, nucleotide diversity in Guineans (θ× 100 = 2·33)is one of the highest found in African populations.
Estimates of genetic contribution to the Canarians from their putative parental populations based on mtDNA (43·25 ± 1·38% Berbers, 35·54 ± 0·55% Spanish, 21·21 ± 1·92% Guineans) showed an important North African substrate. These mtDNA results, when compared with data based on nuclear markers, point to a strong male-female asymmetry, 75% of the Spanish nuclear contribution was due to males and practically all the Berber and Guinean was due to females. These results are in agreement with the way that the Canary Islands were conquered.
Pairwise difference distributions in Guineans and Berbers are compatible with the model of populations in expansion. Departures from a Poisson distribution for the Canarians and Spanish can be explained by admixture and the way of sampling respectively.  相似文献   
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The objective of this study was to assess the expression of Cyclooxygenase-2 (COX-2) and cell proliferation activity (Ki67 expression) in benign, borderline, and malignant serous and mucinous ovarian tumors. Expression of COX-2 and Ki67 proteins were evaluated by immunohistochemistry, in paraffin-embedded sections of ovarian epithelial tumors. The study included 113 serous (67 benign, 15 borderline, and 31 malignant) and 85 mucinous (48 benign, 28 borderline, and 9 malignant) tumors, removed from women who underwent laparotomy between January 1997 and December 2003. From benign to malignant tumors, there was a progressive positive trend in COX-2 expression in both serous and mucinous tumors, more evident in mucinous ones (P < 0.001). Comparing histologic types, COX-2 expression was more prominent in serous than in mucinous benign tumors (P < 0.01), but this difference was not significant in the borderline (P= 0.11) or malignant categories (P= 0.71). There was a progressive Ki67 positivity in line with the tumor histologic gradient for both serous (P < 0.01) and mucinous lesions (P < 0.01), but this increasing expression did not correlate with COX-2 expression in the present series (P= 0.78). There was a higher COX-2 expression in serous ovarian adenomas than in mucinous ones. COX-2 positivity increases in line with the morphologic gradient, from benign to malignant in both histologic types, but it was more prominent in mucinous lesions, pointing to different oncogenic pathways related to different histologic types. A correlation between the expression of COX-2 and Ki67 was not found, suggesting that COX-2 may be required for carcinogenesis, but this pathway is not responsible for cell proliferation in ovarian tumors.  相似文献   
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Staphylococci are a common cause of catheter‐related bloodstream infection (CR‐BSI), and epidemiological typing is an important tool for effective infection control. This study evaluated by PFGE and rep‐PCR whether Staphylococcus aureus strains isolated from skin and catheter tips were related to specimens isolated from blood. A prospective observational study, carried out in a clinical surgical ward at a Brazilian hospital between September 2000 and November 2002, investigated non‐tunneled central venous catheters from 179 patients. S. aureus isolates were mainly obtained from blood (41.4%), while coagulase‐negative staphylococci strains were more often isolated from the skin at the catheter insertion site (49.7%) and from the catheter tip (57.5%). Among the 21 strains isolated from 9 patients at 2 or 3 sites simultaneously, 9 were methicillin‐resistant S. aureus (MRSA) and 12 were methicillin‐susceptible S. aureus (MSSA). Seven patients harbored the same S. aureus strain isolated from the skin, blood and/or catheter tip cultures. MRSA isolates belonged to one PFGE pattern (type A‐ subtypes A1, A2 and A3), and to two rep‐PCR patterns (a and b). MSSA isolates were distinguished in five PFGE (B to F) and in three rep‐PCR (c, d and e) patterns. Both PFGE and rep‐PCR methods indicated that the skin at the catheter insertion site was the origin of CR‐BSI caused by S. aureus.  相似文献   
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