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91.
Aim: To investigate the status of seminal plasma reduced glutathione (GSH) and vitamin E in three different conditions of spennatogenesis: azoospennia, oligozoospennia and nonnospennia. Methods: Reduced glutathione was measured in the seminal plasma by the method of Moron et al (1979), and vitamin E estimation was performed by the method of Taylor et al ( 1976). Results. Vitamin E levels in seminal plasma of oligospermic and azoospelxnic sampies were significantly decreased to 65.54% and 66.04% respectively as compared to the nonnospermic group. Levels of reduced glutathione were also significantly decreased in oligospermic and azoospennic group, and the reduction in azoospermic group (76.73 % ) was more pronounced than oligozoospermic group (62.07 % ). Conclusion: The decrease in reduced glutathione, an endogenous antioxidant, levels in azoospermic and oligozoospermic conditions may cause disruption in the membrane integrity of spermatozoa as a consequence of increased oxidative stress.  相似文献   
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The development of zero-order release systems capable of delivering drug(s) over extended periods of time is deemed necessary for a variety of biomedical applications. We hereby describe a simple, yet versatile, delivery platform based on physically cross-linked poly(vinyl alcohol) (PVA) microgels (cross-linked via repetitive freeze/thaw cycling) containing entrapped dexamethasone-loaded poly(lactic-co-glycolic acid) (PLGA) microspheres for controlled delivery over a 1-month period. The incorporation of polyacids, such as humic acids, Nafion, and poly(acrylic acid), was found to be crucial for attaining approximately zero-order release kinetics, releasing 60% to 75% of dexamethasone within 1 month. Microspheres alone entrapped in the PVA hydrogel resulted in negligible drug release during the 1-month period of investigation. On the basis of a comprehensive evaluation of the structure-property relationships of these hydrogel/microsphere composites, in conjunction with their in vitro release performance, it was concluded that these polyacids segregate on the PLGA microsphere surfaces and thereby result in localized acidity. These surface-associated polyacids appear to cause acid-assisted hydrolysis to occur from the surface inwards. Such systems show potential for a variety of localized controlled drug delivery applications such as coatings for implantable devices.  相似文献   
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beta-Thalassemia is a serious health problem in the United States, especially in California, due to increased Asian immigration. Neonatal screening by using high-performance liquid chromatography (HPLC) or isoelectric focusing (IEF) may lead to confusion due to interactions of various hemoglobinopathies with beta-thalassemia. Our purpose was to develop single-tube multiplexed PCR assays using original neonatal screening specimens to identify the mutations responsible for beta-thalassemia in order to expedite diagnostic confirmation. Primers were designed for two to six common ethnic-specific mutations using the amplification refractory mutation system (ARMS). This multiplex ARMS approach was standardized using DNA samples with known mutations for beta-thalassemia in those of Asian (Southeast Asian, Chinese, and Asian Indian) and African-American descent. Specimens from African-American neonates were tested for two mutations (-88 and -29); Asian Indians for five mutations (IVSI-1, IVSI-5, codons (Cd) 41/42, Cd 8/9, and 619-bp deletion); Chinese, Taiwanese, and Southeast Asians for seven mutations (Cd 41/42, Cd 17, -28, IVSII-654, Cd 71/72, IVSI-5, and IVSI-1). We identified each of these beta-thalassemia mutations in multiplexed ARMS from positive control samples. We tested 25 anonymized dried blood specimens from neonates who had been diagnosed with beta-thalassemia and who also belonged to these ethnic groups. We detected a mutation specific to the neonate's ethnic group using the ARMS approach in nearly all specimens, and the results were confirmed by sequencing. Multiplexed ARMS for ethnic-specific beta-thalassemia mutations from the original newborn screening dried blood specimens is a rapid and efficient approach for diagnostic confirmation.  相似文献   
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Lasers and light therapy for acne vulgaris   总被引:2,自引:0,他引:2  
Acne vulgaris remains an emotionally and debilitating dermatologic disease, and is conventionally treated with a variety of oral and topical therapies with a number of significant side effects. An evolving understanding of laser-tissue interactions involving Propionibacterium acnes-produced porphyrins, and the development of infrared nonablative lasers to target sebaceous glands, has lead to the development of an escalating number of laser, light and radiofrequency devices for acne. Used as monotherapy or in combination, these devices are showing promise as a method to clear acne in a convenient, non-invasive manner, though there remains a clear need for long-term data and randomized, blinded studies.  相似文献   
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AIM: To compare the hematological parameters and pregnancy outcome in women receiving daily versus weekly iron supplements during pregnancy. METHODS: A prospective randomized controlled study was carried out at the Department of Obstetrics and Gynaecology of the All India Institute of Medical Sciences, New Delhi, India, during which 111 women were randomized to receive either 100 mg elemental iron daily (n=55) or 200 mg elemental iron weekly (n=56). Hemogram and serum ferritin level estimation were carried out at the beginning of pregnancy and within the 32-34-week period of gestation. Side-effects, compliance and the number of tablets consumed were noted for each group. The mean birth weight, period of gestation at delivery and mode of delivery were also compared between the two intervention groups. RESULTS: There was no significant difference in the mean hemoglobin levels between the two intervention groups at the end of an average 17 weeks of iron supplementation. However, among anemic women who received daily supplementation, there was a greater rise in hemoglobin compared with those receiving supplementation weekly. The serum ferritin level was lower in the weekly supplemented group compared with that in the daily. There was no difference in the mean birth weight, period of gestation and mode of delivery between the two groups. Side-effects and non-compliance were significantly higher (P<0.001) in the daily supplemented group. CONCLUSIONS: Weekly iron supplementation is an effective option for prophylaxis in non-anemic pregnant women, but has less than optimal benefit in anemic women.  相似文献   
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Hypertonic saline solutions in brain injury   总被引:3,自引:0,他引:3  
PURPOSE OF REVIEW: Hypertonic saline solutions have received renewed attention as effective agents for the treatment of cerebral edema and in brain resuscitation in a variety of brain injury paradigms. Although evidence of the beneficial action of hypertonic saline solutions in traumatic brain injury is robust, data supporting use in other conditions are only now mounting. RECENT FINDINGS: Osmotic properties of hypertonic saline solutions have been well studied in laboratory-based studies in animal models and in patients with acute brain injury. There are, in addition, emerging data on the extraosmotic actions on brain pathophysiology. This review cites baseline literature and provides new evidence of actions of hypertonic saline solutions: (a). in augmenting cerebral blood flow after subarachnoid hemorrhage, (b). as an antiinflammatory adjunct, and (c). utility in chemonucleolysis for intervertebral disc disease and treatment of seizures associated with severe hyponatremia. SUMMARY: Brain injury from diverse etiologies including trauma, ischemic stroke, global cerebral ischemia from cardiac arrest, intraparenchymal or subarachnoid hemorrhage, infection, or toxic-metabolic derangements are commonly encountered in the clinical setting. Many of these conditions are associated with cerebral edema with or without elevated intracranial pressure. Osmotherapy constitutes the cornerstone of medical therapy for such patients. Hypertonic saline solutions have received renewed attention in clinical practice as osmotic agents for cerebral resuscitation. This article reviews experimental and clinical evidence of the efficacy of hypertonic saline solutions and elaborates on their use in patients with acute neurologic injury. Important areas for current and future research are highlighted before the use of hypertonic saline solutions can be accepted for widespread use.  相似文献   
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