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971.
The pituitary prolactin (PRL) response to domperidone (DOM; a dopaminergic antagonist) and TRH administration in human males during different stages of sexual maturation was investigated. Dopaminergic blockade caused an immediate and significant PRL release in all subjects, regardless of the stage of pubertal development. Even though the mean values of peak PRL levels, magnitude of PRL response (delta PRL) and areas under the PRL curve were not significantly different among the different groups, all these parameters showed a clear tendency to increase in parallel to the stage of pubertal development, as indicated by significant positive correlations between age and pubertal stage of the subjects and the magnitude of their PRL response to DOM (r = 0.661, p less than 0.01 and r = 0.536, p = 0.01, respectively). Significant positive correlations also were found between the serum sex steroid hormone concentrations and the PRL response to dopaminergic blockade (r = 0.774, p = 0.02 and r = 0.554, p = 0.01, respectively). In contrast to these findings, no significant differences or tendencies were detected in the PRL responses to TRH among the different subject groups. The different patterns of PRL response to DOM and TRH throughout male puberty might be due to differences in pituitary thresholds for sex steroids between the dopamine- and TRH-dependent intracellular pools.  相似文献   
972.
From 1979 to August 1987, there have been 178 cases of meningococcal disease in Iquique, Chile, a city of about 140,000. The attack rate for the last 5 years has been in excess of 20/100,000 per year, more than 20 times greater than for the country overall. The mortality rate was 6%. The disease occurred in patients with ages from 4 months to 60 years, but 89% of cases were in patients less than 21 years. The largest number of cases were in the age group 5-9 years (n = 54), but the highest incidence occurred in children less than 1 year of age (72.8/100,000 per year). The male/female ratio was 1.2. Cases occurred all year round with little seasonal variation. Of the 178 cases, 173 were biologically confirmed. Serogroup analysis of strains from 135 patients revealed A = 1, B = 124, C = 10. Forty-four group B strains from 1985-7 were serotyped: 15:P1.3 = 36, 15:NT = 4, 4:P1.3 = 2, NT:NT = 2. Ten of 11 of the outbreak strains tested were sulfadiazine-resistant. This is the first recognized outbreak caused by a Gp B:15 strain in South America. It shares many of the characteristics of outbreaks caused by closely related strains in Europe, such as a predilection for older children and adolescents, sulfadiazine-resistance, and sustained high attack rates. The Iquique strain (B:15:P1.3) belongs to the same genetic clone (ET-5 complex) as the Norway (B:15:P1.16) and the Cuban (B:4:P1.15) strains.  相似文献   
973.
Developmental stuttering (DS) is a disturbance in the normal fluency and time patterning of speech resulting in involuntary repetition, prolongation, or cessation of sound. The scientific literature has implicated the lack of strong left cerebral dominance and abnormal levels of the neurotranemitters dopamine and possibly serotonin in regions of the brain controlling the coordination of language processing and motor activity of the vocal apparatus as possible causative factors in DS. Speech-language therapy is the most common form of treatment, but antipsychotic, antide-pressant, and anxiolytic medications may be prescribed for some children and adults with persistent stuttering. These medications may cause xerostomia and adversely interact with certain antibiotics, analgesics, and sedatives routinely used in dentistry. Some people who stutter have sensory-motor and tactile-proprioceptive deficits that impede accurate and timely movements of the mandible, lips, and tongue, necessitating protection of the airway by staff during dental care.  相似文献   
974.
975.
976.
Infusion of atrial natriuretic peptide (ANP) increases the glomerular filtration rate (GFR), and ANP is released from cardiac myocytes in response to extracellular fluid volume expansion. Since diabetes mellitus is associated with glomerular hyperfiltration and volume expansion, we investigated the relationship between ANP and GFR in diabetic rats given insulin to achieve stable moderate hyperglycemia or normoglycemia. At 2 wk after induction of diabetes, moderately hyperglycemic diabetic rats exhibited elevations of plasma ANP levels averaging 281 +/- 28 pg/ml vs. 158 +/- 15 pg/ml in normoglycemic diabetic rats. In hyperglycemic rats, the GFR was also elevated on average to 2.24 +/- 0.28 ml/min as compared with 1.71 +/- 0.13 ml/min in normoglycemic diabetic rats. To test further the relationship between ANP and GFR in diabetes, moderately hyperglycemic diabetic rats were infused either with a specific ANP antiserum or with nonimmune serum. The infusion of specific ANP antiserum uniformly reduced the GFR on average from 2.38 +/- 0.1 ml/min to 1.60 +/- 0.1 ml/min, whereas the infusion of nonimmune serum was without effect. It is concluded that elevated endogenous ANP levels contribute to the hyperfiltration observed in early diabetes in the rat.  相似文献   
977.
During a 2-year period (December 1987-December 1989), 165 Department of Defense (DoD) military hospitals world-wide provided 71,800 cases with 83,197 reviews for quality of care evaluations by the Civilian External Peer Review Program (CEPRP). The majority (78,246 of 79,896) of completed peer review determinations (97.9%) generated agreement with care and documentation. It is concluded that health care in military treatment facilities is of high quality, meeting and generally exceeding accepted standards of care. It is also concluded that the DoD CEPRP offers conceptual and practical experience to guide the further evolution and integration of clinical peer review and quality improvement activities.  相似文献   
978.
979.
Neurobehavioral changes associated with caudate lesions   总被引:10,自引:0,他引:10  
We report behavioral and cognitive characteristics of 12 patients with caudate nuclei lesions, 11 unilateral and one bilateral. These patients developed an acute behavioral change characterized by apathy, disinhibition, or a major affective disturbance. The pattern of personality change correlated with size and location of lesion within the caudate but not the laterality. Seven patients were further compared with matched controls on a series of neuropsychological tests. Their performance was impaired on tasks requiring planning and sequencing. They had short attention spans and decreased free recall of episodic and semantic items with good recognition memory scores. Similar behavioral and cognitive changes also occur in early Huntington's disease, frontal-lesioned patients, and caudate-lesioned animals, and correspond to disturbances of specific frontal-caudate circuits. These results implicate the caudate nuclei in mediating prefrontal behaviors and possibly in the conceptual integration of memories.  相似文献   
980.
This review is divided in several items. A brief introduction on the characterization of the growth processes is made; the ways of assessing fetal development and well-being, the factors acting on fetal growth and birth weight, the causes and post-natal consequences of prematurity and intrauterine growth retardation are discussed in the first part. The following items deal mainly with: the normal pattern of growth from birth to puberty according to sex, race, and nutritional status, with special mention to pubertal changes; methods for predicting adult height from skeletal age; the effect of hormones during pre- and post-natal life; and the genetics of adult stature. The remainder of this review deals with genetic causes of growth abnormalities. Constitutional delay of growth, familial short stature, hypothalamic-pituitary dwarfism, skeletal dysplasias and many genetic syndromes presenting intrauterine growth retardation are listed. Aneuploidy effects on human growth are extensively reviewed, and usual growth patterns in Down and Ullrich-Turner syndrome patients as well as other sex aneuploid individuals and mosaics are fully described. The influences of X and Y chromosomes on growth and maturation are also discussed. Finally, some remarks are made about overgrowth syndromes.  相似文献   
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