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751.
Three infant gorillas born at the Yerkes Regional Primate Research Center of Emory University were studied during their first year and one-half of life for various aspects of behavior, including solitary and social play, using both focal animal and one-zero sampling. The appearance of play in these infants followed a developmental trend, beginning with mother-infant play, and followed by solitary play, and then social play among peers. Mothers were initially very vigilant, repeatedly interrupting infant peer play bouts, this relaxing toward the end of the first year. Evidence for a possible sex difference in active social play is presented.  相似文献   
752.
Nowadays, great attention is devoted to minimizing the discomfort caused by connection of patients to sensors for long-term monitoring of physiological parameters. Hence, the need for contact-less monitoring systems is increasingly recognized in clinical investigation. To this aim, audio signals recorded by ambient microphones are an appealing and increasing field of research: in the biomedical field, application of contact-less audio recording of long duration may concern obstructive apnoea syndrome, preterm newborns in Intensive Care Units, daily monitoring in occupational dysphonia, speech therapy, Parkinson and Alzheimer disease, monitoring of psychiatric and autistic subjects, etc. However, a significant amount of ambient noise is inevitably included in the records.Especially in the case of recordings that take a long time, manual extraction of clinically useful information from a whole record is a time-consuming operator-dependent task, the length of a whole recording (even several hours) being prohibitive both for perceptual analysis made by listening to it and for visual inspection of signal patterns. Moreover, objective measures of signal characteristics may serve clinicians as a common ground for diagnosis. Hence, automatic methods are needed to speed up and objectify the analysis task.The present work describes a new, automatic, fast and reliable method for extracting “voiced candidates” from audio recordings of long duration for both clinical and home applications.To demonstrate its effectiveness, the method is compared to existing software tools commonly used in biomedical applications using synthetic signals.  相似文献   
753.
目的:比较先兆早产、胎膜早破、妊娠期糖尿病及正常妊娠女性阴道菌群分布情况。方法:选择2016年6月至2018年6月在苏州大学附属第二医院妇产科住院的妊娠女性806例,其中先兆早产组206例,胎膜早破组234例,妊娠期糖尿病组156例,正常妊娠组210例。记录四组女性异常阴道菌群检出率及异常阴道菌群分布情况。结果:四组女性的年龄、孕周比较无统计学差异(P>0.05)。先兆早产组、胎膜早破组异常阴道菌群检出率高于妊娠期糖尿病组、正常妊娠组(P<0.05),而妊娠期糖尿病组、正常妊娠组异常阴道菌群检出率比较无统计学差异(P>0.05)。先兆早产组、妊娠期糖尿病组白色假丝酵母菌检出率高于胎膜早破组、正常妊娠组(P<0.05),先兆早产组、胎膜早破组阴道加德纳菌检出率高于妊娠期糖尿病组、正常妊娠组(P<0.05),先兆早产组无乳链球菌检出率高于胎膜早破组、妊娠期糖尿病组、正常妊娠组(P<0.05),胎膜早破组大肠埃希菌检出率高于先兆早产组、妊娠期糖尿病组、正常妊娠组(P<0.05)。结论:妊娠女性阴道感染以白色假丝酵母菌、大肠埃希菌、无乳链球菌、阴道加德纳菌为主,且先兆早产、胎膜早破女性阴道致病菌感染率较高,妊娠期糖尿病女性阴道白色假丝酵母菌的感染率较高。  相似文献   
754.
Women and female great apes both continue giving birth into their forties, but not beyond. However humans live much longer than other apes do. 1 Even in hunting and gathering societies, where the mortality rate is high, adult life spans average twice those of chimpanzees, which become decrepit during their fertile years and rarely survive them. 2 , 3 Since women usually remain healthy through and beyond childbearing age, human communities include substantial proportions of economically productive postmenopausal women. 4 - 7 A grandmother hypothesis8–12 may explain why greater longevity evolved in our lineage while female fertility still ends at ancestral ages. This hypothesis has implications for the evolution of a wide array of human features. Here we review some history of the hypothesis, recent findings, and questions for ongoing research.  相似文献   
755.
Aim:  To explore safe guidelines for manufacturers and consumers to prepare, handle and store dry infant formula (DIF) to protect infants against Cronobacter spp.
Methods and Results:  Selected strains (2.45, FSM 293, ATCC-12868, FSM-271) screened from 68 strains of Cronobacter spp . were used to study growth and survival in commercial DIF. Prototype growth patterns in Enterobacteriaceae enrichment broth (EEB) containing a cocktail comprised of ATCC 12868, ATCC 29004, ATCC 29544 and ATCC 51329 showed a rapid increase in cell count (2·0 log10 to 6·2 log10 CFU ml−1). Infant formula provided a better protective environment for the cells of Cronobacter strains than did buffered peptone water . Experiments on survival in inoculated (104–106 CFU ml−1) reconstituted infant formula (RIF), preparation temperature, the effect of preparation volume (one-serving or two-serving) and effect of storage at room temperature for up to 10 h provided information to develop consumer guidelines for DIF preparation and handling.
Conclusions:  Reconstituted DIF in water at >70°C in larger volumes, minimizing storage time before feeding and storing unused reconstituted formulate at <4°C, may reduce the risk of Cronobacter infection in infants.
Significance and Impact of the Study:  Meningitis, necrotizing enterocolitis and bacteremia in premature babies has been linked to contaminated milk powder and DIF; better handling practices may improve the safety of these foods for neonates.  相似文献   
756.
Sixty-five interactions where an adult male carried an infant in the proximity of a second male were observed during a 19-mo period in a captive sooty mangabey (Cercocebus atys) social group. The behavior was distributed nonrandomly in both the adult male and infant classes. In all but three of the interactions, the recently deposed alpha male carried an infant in the presence of the newly ascendant dominant male. In the first phase of the study, infants that were carried included the entire unweaned infant cohort (n = 5) born before the rank reversal. The rate of carrying in this class declined as a function of increasing infant age and time since the rank reversal. Infant carrying was not observed in the context of fighting, which was rare, and intermale aggression never preceded the behavior. However, in 40% of the cases, carrying occurred after an infant had been threatened by the dominant male. These results suggest that infant carrying served to protect the infant from aggression rather than to exploit the infant as an agonistic buffer. The data did not unequivocally support the postulate that carrying may be a form of paternal care since paternity could not be assessed. The similar structural and contextual patterns of infant carrying in this species suggest a common origin for triadic male-infant interactions in mangabeys and baboons.  相似文献   
757.
The effect of hybridization on infant survival was investigated in subspecific crosses of the saddle-back tamarin (Saguinus fuscicollis) at the Oak Ridge Associated Universities (ORAU) Marmoset Research Center (Oak Ridge, TN). Cox Proportional Hazards Regression was used to compare infant survival between (1) pure subspecies, (2) F1, F2, and backcrossed hybrids, and (3) hybrids and their parental subspecies. Also, effects of management changes, sex, and litter size on infant survival were investigated. There were no significant differences in infant survival between the pure subspecies. Also, degree of hybridization (F1, F2, or backcross) did not have a significant effect on infant survival. Progeny of hybrid crosses between S. f. lagonotus and S. f. illigeri was found to have significantly (P < 0.05) higher infant survival than both of their parental subspecies. Individuals born after diet and management changes in the colony had significantly (P < 0.05) higher survival than those born before. There were no significant sex differences in infant survival. Individuals born into triplet litters had significantly (P < 0.05) lower survival than those born into twin litters. These results show heterosis (hybrid vigor) for infant survival in one subspecific S. fuscicollis cross (S. f. lagonotus × S. f. illigeri). The results suggest genetic divergence between the subspecies populations and possible reproductive isolation in the wild. © 1994 Wiley-Liss, Inc.  相似文献   
758.
A young-male underwent radiofrequency (RF) ablation of ventricular premature contractions (VPCs) of over 30,000/day and the morphology exhibited left bundle branch block and a superior axis, which indicated the VPCs originated from the inferior portion of the right ventricle (RV). While the PENTARAY catheter was placed under the tricuspid valve (TV), the earliest potential, which preceded the QRS onset by 34 ms, was recorded. Pace mapping there presented a very similar QRS morphology to the target VPC. However, the radiofrequency (RF)-catheter could not be placed under the TV even when a deflectable sheath was used, because the deflectable curve of the RF-catheter was larger than that of the PENTARAY. An over-the-vale RF application was not effective, so the trans-jugular approach with a deflectable sheath was indicated. The tip of the sheath was placed at a higher portion of the RV cavity to maintain an adequate distance for the RF-catheter tip to be deflected and placed under the TV. With this maneuver, the tip of the RF-catheter was successfully placed under the TV, which was confirmed by intracardiac ultrasound. Small atrial potentials and larger ventricular potentials could be recorded from the distal tip of the RF-catheter, which might indicate that the tip was placed at the TV annulus. An RF application at that site permanently abolished the VPC. Placing the tip of the RF-catheter under the TV by the femoral approach is very difficult in some cases. The trans-jugular approach with a deflectable sheath is one option for arrhythmias from the TV.  相似文献   
759.
In humans, temperament plays an important role in socialization and personality. Some temperaments, such as behavioral inhibition are associated with an increased risk for psychopathology. Nonhuman primates can serve as a model for neurobiological and developmental contributions to emotional development and several recent studies have begun to investigate temperament in nonhuman primates. In rhesus monkeys, dominance rank is inherited from the mother and is associated with social and emotional tendencies that resemble differences in temperament. The current study assessed differences in temperament in infant rhesus monkeys as a function of maternal dominance rank. Temperament was assessed in 26 infants (13 males) from birth until 6 months of age with a battery that included Brazelton test, human intruder test, human intruder‐startle, cortisol stress reactivity, and home cage observations of interactions with peers and the mother. Throughout testing, infants lived with their mothers and a small group of other monkeys in indoor/outdoor runs. Dominance rank of the mothers within each run was rated as either low/middle (N = 18, 9 male) or high/alpha (N = 8, 4 female). Infants of high‐ranking mothers displayed more intruder‐directed aggression and reduced startle potentiation in the human intruder tests. Dominant offspring also had reduced levels cortisol and startle across development and spent more time away from mothers in the interaction tests. These results suggest that dominance of the mother may be reflected in behavioral reactivity of infants early in life. These findings set up future studies, which may focus on contributing factors to both dominance and temperament such as genetics, rearing, and socialization. Such factors are likely to interact across development in meaningful ways. These results also suggest future human‐based studies of a similar relationship may be warranted, although social dominance is clearly more complex in human than macaque societies. Am. J. Primatol. 75:65‐73, 2013. Published 2012 by Wiley Periodicals, Inc.?  相似文献   
760.
This explorative study was performed to assess basic data on the Mo metabolism of premature infants. Premature (n=18, gestational age ≤32 wk, birth weight ≤1500 g) and healthy formula-fed term infants (n=14) were nourished and corrected for gestational age, identically. Plasma was collected at 3, 16, and 52 wk and 72 h balances were performed at 3 wk of age. In the premature infants, these investigations were preceded by two balance studies and an initial plasma collection. Increased Mo intake and low relative urinary excretion resulted in a retention of 4.4 (0.99–7.77) μg Mo/kg initially in premature infants (median, range). Parallel plasma concentrations were 5.5 (2.5–7.3) μg Mo/L, declining to 2.36 (0.73–3.87) μg Mo/L at 4 wk. Term infants rendered 1.49 (0.29–1.7) μg Mo/L (p<0.05), with no significant differences later. It was concluded that the supplementation of formulas for premature infants with Mo should be recinded until there is evidence for its necessity.  相似文献   
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