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141.
OBJECTIVE: We evaluated the seroprevalence for measles, mumps, and rubella in school-age children (6-12 years old) before and after the administration of three triple combined viral vaccines. METHODS: In two municipal schools of Rio Grande do Sul, Brazil, 692 blood samples were collected before vaccination and 636 samples 21 to 30 days after vaccination during 1996. IgG antibody seropositivity was investigated by enzyme-linked immunosorbent assay (measles and mumps with Enzygnost [Behring, Marburg, Germany]; rubella with Rubenostika [Organon Teknica, Boxtel, the Netherlands]). The vaccines compared were: A: E-Zagreb, L-Zagreb, and Wistar RA 27/3 (Tresivac); B: Moraten, J-Lynn, and Wistar RA 27/3 (M-M-R II); and C: Schwarz, Urabe AM-9, and Wistar RA 27/3 (Trimovax). RESULTS: Before vaccination, 79.2% [95% confidence interval (CI)=76.0%-82.2%] of the samples were positive for measles, 69.4% (95% CI=65.8%-72.8%) for mumps, and 55.4% (95% CI=51.6%-59.2%) for rubella. After vaccination with the A, B, and C vaccines, seropositivity was 100.0%, 99.5%, and 100.0%, respectively for measles; 99.5%, 94.5%, and 92.0% for mumps; and 92.6%, 91.3%, and 88.6% for rubella. CONCLUSIONS: About one-fifth (20.8%) of the schoolchildren who could have been vaccinated against measles at age 9 months had levels of antibodies insufficient for protection. In the sample of schoolchildren without previous vaccination against mumps and rubella, high proportions of susceptible levels were found. All vaccines were immunogenic, but vaccine A yielded a seroconversion rate of 99.5% for the mumps component, which was significantly higher than the other two vaccines (P<0.01).  相似文献   
142.
Diabetic nephropathy (DN) is the leading cause of kidney disease in patients starting renal replacement therapy, and affects up to 40% of type 1 and type 2 diabetic patients. Diet seems to play an important role in the development of the disease. There are evidences supporting the concept that not only the amount but also the origin of dietary protein are associated with DN. Few studies analyzed the role of dietary lipids. A low-protein diet slows down the decline of renal function and ameliorates the DN prognosis and death in patients with type 1 diabetes with micro- and macroalbuminuria. Studies in type 2 diabetic patients are scanty but short-term studies suggest that this approach decreases albuminuria. However, the use of low-protein diet for long periods is compromised by poor compliance and its long-term safety is not firmly established. Enthusiastic results come up when comparing the effect of different sources of animal protein on renal function and lipid profile in patients with DN, which may represent an alternative strategy for low-protein diet on medical nutritional therapy in patients with DN and in cardiovascular risk factors and endothelial function.  相似文献   
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AIM: To assess breastfeeding practices, focusing on the prevalence and the determinants of exclusive breastfeeding during hospital stay. METHODS: A cross-sectional study of 1603 healthy women, who delivered healthy infants weighing more than 2500 g, was conducted in the area of Athens, Greece. Participants completed a self-administered questionnaire on the day they were discharged from the maternity ward. Classification of breastfeeding and recall period from birth to discharge were in accordance with the WHO criteria. Hierarchical logistic regression analysis was used to study determinants of exclusive breastfeeding initiation. RESULTS: Breastfeeding initiation was reported by 96.1% of the participants. However, exclusive breastfeeding was initiated only in 19.1% and predominant breastfeeding in 7.2% of the cases. The univariate analysis showed that maternal younger age, low educational level, unemployment, vaginal delivery, infant birthweight >3000 g, multiparity, early initiation of breastfeeding, rooming-in and awareness on the existence of breastfeeding centres were associated with higher rates of exclusive breastfeeding. Logistic regression analysis revealed that rooming-in (OR 3.72, p<0.01), demand feeding (OR 2.18, p<0.01), type of delivery (OR 1.61, p<0.01) and the source of information received about breastfeeding are more important determinants of exclusive breastfeeding than the socio-demographic parameters. CONCLUSIONS: Exclusive breastfeeding during hospital stay in the area of Athens is low. Demand feeding and rooming-in positively influence exclusive breastfeeding initiation, while caesarean section and information by mass media have a negative impact.  相似文献   
145.

Background/Purpose

Medial layer hypertrophy of hepatic arterial branches may be associated with biliary atresia (BA) pathogenesis. This study aimed at evaluating medial layer thickness in hepatic arterial branches at portoenterostomy and liver transplantation.

Methods

The authors evaluated 1274 arterial branches both in BA cases and in control subjects involving a total of 1108 arterioles and 166 arteries. Arterial branch characteristics were morphometrically evaluated in 47 BA patients at the time of portoenterostomy. Controls were patients with intrahepatic cholestasis (n = 3), immature neonates (n = 7), and infants (n = 7) without liver disease. Progression of medial layer thickening between the time of portoenterostomy and transplantation was evaluated in 7 BA patients. Biliary atresia patients at the time of transplantation were compared with non-BA-transplanted patients (n = 4).

Results

The arterial medial layer of BA cases at portoenterostomy was thicker than that of infants without liver disease (P = .03). The arterial medial thickness increased during the interval between portoenterostomy and transplantation (P = .05). Arterioles and arteries with thickened medial layers were found in transplanted BA patients but not in patients transplanted for other liver diseases (P = .05 and P = .01). Thickening of the medial layer of the hepatic arteries was associated with focal distribution of interlobular bile ducts in portal spaces in BA (P = .02).

Conclusions

In BA, there is a progressive thickening of the arterial medial layer, suggestive of vascular remodeling, which is associated to the disappearance of interlobular bile ducts.  相似文献   
146.
Thrombospondin (TSP) 1 and 2, share the same overall structure and interact with a number of the same cell-surface receptors. In an attempt to elucidate their biological roles more clearly, we generated double-TSP1/TSP2-null animals and compared their phenotype to those of TSP1- and TSP2-null mice. Double-null mice exhibited an apparent phenotype that primarily represented the sum of the abnormalities observed in the single-null mice. However, surprisingly, the wound-healing response in double-null mice resembled that in TSP1-null animals and differed from that in TSP2-nulls. Thus, although the excisional wounds of TSP2-null mice are characterized by increased neovascularization and heal at an accelerated rate, TSP1-null and double-null animals demonstrated delayed healing, as indicated by the prolonged persistence of inflammation and delayed scab loss. Immunohistochemical analysis showed that, similar to TSP1-null mice, the granulation tissue of double-null mice was not excessively vascularized. Furthermore as in TSP1-nulls, decreases in macrophage recruitment and in the levels of monocyte chemoattractant protein-1 indicated that the inflammatory phase of the wound-healing response was impaired in double-null mice. Our data demonstrate that the consequences of a lack of TSP1 predominate in the response of double-null mice, and dictate the course of wound healing. These findings reflect distinct temporal and spatial expressions of TSP1 and TSP2 in the healing wound.  相似文献   
147.
The development of neotissue in tissue engineered vascular grafts remains poorly understood. Advances in mouse genetic models have been highly informative in the study of vascular biology, but have been inaccessible to vascular tissue engineers due to technical limitations on the use of mouse recipients. To this end, we have developed a method for constructing sub-1mm internal diameter (ID) biodegradable scaffolds utilizing a dual cylinder chamber molding system and a hybrid polyester sealant scaled for use in a mouse model. Scaffolds constructed from either polyglycolic acid or poly-l-lactic acid nonwoven felts demonstrated sufficient porosity, biomechanical profile, and biocompatibility to function as vascular grafts. The scaffolds implanted as either inferior vena cava or aortic interposition grafts in SCID/bg mice demonstrated excellent patency without evidence of thromboembolic complications or aneurysm formation. A foreign body immune response was observed with marked macrophage infiltration and giant cell formation by post-operative week 3. Organized vascular neotissue, consisting of endothelialization, medial generation, and collagen deposition, was evident within the internal lumen of the scaffolds by post-operative week 6. These results present the ability to create sub-1mm ID biodegradable tubular scaffolds that are functional as vascular grafts, and provide an experimental approach for the study of vascular tissue engineering using mouse models.  相似文献   
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149.
In patients with type 2 diabetes mellitus (DM), the factors associated with under- or overreporting of protein intake in nutrition assessment tools, as well as the variability of diet records, have not been fully established. The aim of this cross-sectional study was to evaluate factors associated with under- or overreporting of protein intake and its variability in patients with type 2 DM. Protein intake was estimated in 205 patients (aged 59.8±9.6 years) using 3-day weighed diet records and 24-hour nitrogen output (criterion standard). Twenty-three patients repeated the 3-day weighed diet records three times. Clinical, nutrition, and lifestyle evaluations were performed. Coefficients of variation were calculated for protein intake. Factors associated with under- and overreporting were assessed using multivariate logistic regression models. Coefficients of variation for protein intake estimated by weighed diet records or nitrogen output were similar (11.9% vs 11.3%; P>0.05). Using Beaton's formula, a difference of 16.5% in protein intake between two 3-day weighed diet records was acceptable. The lowest A1c test tertile (≤6.9%) was associated with protein intake underreporting (odds ratio [OR]=0.40; 95% confidence interval [CI]=0.16 to 0.99; P=0.046] after adjustment for sex, age, employment status, and living alone. Male sex (OR=6.66; 95% CI: 2.08 to 22.07; P=0.002), A1c test (OR=1.29; 95% CI: 1.02 to 1.64; P=0.036), and body mass index (OR=0.89; 95% CI: 0.80 to 0.994; P=0.039), adjusted for physical and employment status, education, and preparing one's own meals, were associated with overreporting. In conclusion, in patients with type 2 DM, a difference >16.5% in protein intake between two 3-day weighed diet records should be interpreted as a true discrepancy. Poor glucose control and male sex increase the chance of inaccurate 3-day weighed diet records.  相似文献   
150.
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