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21.
BACKGROUND: To identify risk factors associated with fetal death, and to measure the rate and the risk of fetal death in a large cohort of Latin American women. METHODS: We analyzed 837,232 singleton births recorded in the Perinatal Information System Database of the Latin American Center for Perinatology and Human Development (CLAP) between 1985 and 1997. The risk factors analyzed included fetal factors and maternal sociodemographic, obstetric, and clinical characteristics. Adjusted relative risks were obtained, after adjustment for potential confounding factors, through multiple logistic regression models based on the method of generalized estimating equations. RESULTS: There were 14,713 fetal deaths (rate=17.6 per 1000 births). The fetal death risk increased exponentially as pregnancy advanced. Thirty-seven percent of all fetal deaths occurred at term, and 64% were antepartum. The main risk factors associated with fetal death were lack of antenatal care (adjusted relative risk [aRR]=4.26; 95% confidence interval, 3.84-4.71) and small for gestational age (aRR=3.26; 95% CI, 3.13-3.40). In addition, the risk of death during the intrapartum period was almost tenfold higher for fetuses in noncephalic presentations. Other risk factors associated with stillbirth were: third trimester bleeding, eclampsia, chronic hypertension, preeclampsia, syphilis, gestational diabetes mellitus, Rh isoimmunization, interpregnancy interval<6 months, parity > or =4, maternal age > or =35 years, illiteracy, premature rupture of membranes, body mass index > or =29.0, maternal anemia, previous abortion, and previous adverse perinatal outcomes. CONCLUSIONS: There are several preventable factors that should be dealt with in order to reduce the gap in fetal mortality between Latin America and developed countries.  相似文献   
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The purpose of this study was to determine whether the early artificial rupture of the amniotic membranes performed to shorten the duration of an otherwise normal labor and delivery might have potentially deleterious effects on the fetus that would be reflected in the neonate. In 38 infants delivered at term, acid-base balances and O2 and CO2 pressures were obtained in umbilical arterial and venous blood at birth, prior to the first inspiration. For the purpose of the study the infants were divided into two groups: group I infants were born after a normal labor in which the amniotic membranes were permitted to rupture spontaneously at full cervical dilatation; group II infants were born after a labor in which the membranes were ruptured artificially when cervical dilatation was 4 to 5 cm. There was no evidence of fetal distress, and all infants were vigorous at birth. The pH of umbilical venous blood was greater in the group with late rupture of the membranes (fiftieth percentile [P50] = 7.36) than in those born after early amniotomy (P50 = 7.30) (p less than 0.01). The pH values of umbilical arterial blood were also higher in the group I infants (P50 = 7.31) than in those born after amniotomy (P50 = 7.25)(p less than 0.025). These differences were also observed in the 19 neonates in whom the cord was not encircled around the neck at the time of birth. The PCO2 in umbilical venous blood was less, and the hemoglobin saturation was greater (P less than 0.05) in group I infants than in those of group II. It is possible that the influence of early amniotomy on fetal pH may be deleterious in infants born after high-risk pregnancies in which the uteroplacental circulation is impaired.  相似文献   
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Objective To assess in an animal model the effect of maternal dietary calcium intake during pregnancy on the blood pressure of offspring.
Design Randomised controlled trial.
Sample Ninety-eight 20-week-old female Wistar–Kyoto rats, giving birth to a total of 119 pups that were included in the follow up study.
Methods Rats were randomised to a calcium deficient diet, a diet with the recommended calcium levels, or a diet with calcium content much higher than the recommended levels. After one month on the experimental diet they were bred. After birth, systolic blood pressure in the offspring was measured monthly till 52 weeks of age.
Main outcome measures Blood pressure of the offspring.
Results The difference in blood pressure of the offspring between the normal and low maternal calcium group increased 0.49 mmHg per month (95% CI 0.18 to 0.84), 0.38 (0.07 to 0.68) between the low and high calcium group, and 0.12 (−0.20 to 0.43) between the normal and high calcium group. At the end of the follow up (52 weeks of age) blood pressure of the offspring in the deficient calcium group was 12.1 mmHg (95% CI 8.8 to 15.4,   P < 0.0001  ) higher than in the normal calcium group and 7.5 mmHg (95% CI 4.4 to 10.5,   P < 0.001  ) higher than the high calcium group. Blood pressure of the offspring in the high calcium group was 4.3 mmHg (95% CI 1.0 to 7.5,   P = 0.0l  ) higher than in the normal calcium group. In a multiple regression model maternal calcium intake during pregnancy was the strongest predictor of blood pressure of the offspring during adulthood.
Conclusions This experiment supports previous studies in humans suggesting a link between calcium intake during pregnancy and blood pressure in the offspring, and provides an animal model to explore the mechanisms involved in such association.  相似文献   
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The objective of our study was to investigate chondrogenesis potential of human adipose‐derived mesenchymal stromal cells (MSCs), using as a positive control a human source of cartilage‐derived progenitor cells (PCs). This source of PCs was recently described by our group and dwells on the surface of nasoseptal cartilage. Histological analysis using Safranin O staining and immunofluorescence for actin filaments and collagen type II was performed on three‐dimensional (3D) pellet cultures. Cartilage PCs and adipose MSCs showed similarities in monolayer culture related to cell morphology and proliferation. Our 3D pellet cultures substantially reduced the actin stress and after 21 days under chondrogenic medium, we observed an increase in the pellet diameter for cartilage PCs (7.4%) and adipose MSCs (21.2%). Adipose‐derived MSCs responded to chondrogenic stimulus, as seen by positive areas for collagen type II, but they were not able to recreate a mature extracellular matrix. Using semi‐quantitative analysis, we observed a majority of Safranin O areas rising from blue (no stain) to orange (moderate staining) and no changes in fibroblastic morphology (P < 0.0001). For cartilage PCs, chondrogenic induction is responsible for morphological changes and a high percentage of matrix area/number of cells (P ≤ 0.0001), evaluated by computerized histomorphometry. Morphological analyses reveal that adipose‐derived MSCs were not able to recreate a bioengineered cartilage. The cost of culture was reduced, as the cartilage PCs under growth‐factor free medium exhibit a high score for cartilage formation compared with the induced adipose mesenchymal stromal cells (P = 0.0021). Using a pellet 3D culture, our cartilage PCs were able to produce a cartilage tissue in vitro, leading to the future development of bioengineered products.  相似文献   
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Background  

To provide data on overweight, obesity and hypertension among adolescent girls in Norway and Argentina.  相似文献   
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It is important to diagnose epilepsy in a timely and accurate manner, and also to distinguish it from non-epileptic conditions. The present study was aimed at determining postictal serum prolactin levels and lactate dehydrogenase (LDH) activities in patients with new-onset seizure admitted to the emergency department in order to assess whether they could be used in the differentiation of epileptic seizure (ES) from nonepileptic seizure (NES).Eighty-five patients were included prospectively in this study. Patients were divided into 2 groups with respect to epilepsy diagnosis, and the final groups were comprised of 36 patients with ES and 49 patients with NES. Blood samples were obtained within 1 hour of seizure.No significant differences between groups were observed in prolactin levels and in the percentage of patients with abnormal prolactin level (P = .569 and .239, respectively). The median LDH activity was significantly higher in those with ES compared with those with NES (P = .031). The percentage of patients with elevated LDH levels was similar between 2 groups (P = .286).This was the first study to examine LDH activities in terms of its role in differentiation of seizure origin in the postictal period in patients hospitalized with seizure. Our study demonstrated that serum LDH activities within 1 hour after the seizure appear to be increased in patients with ES compared with those with NES, suggesting the potential role of LDH activities as a diagnostic tool in distinction of seizure types. Our study supports the hypothesis that LDH-antagonists may have a role in the management of seizure and epilepsy.  相似文献   
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