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11.
Seventy-one neuropathic ulcers of the foot in sixty-six patients were treated with the use of a total-contact cast. The ulcers had been present for an average of five months (range, one to twenty-nine months) and were graded according to the Wagner classification; only patients who had grade-I or grade-II lesions were treated with a total-contact cast. The diameter of the ulcer averaged 3.5 centimeters (range, 1.5 to 15.5 centimeters). Sixty-four (90 per cent) of seventy-one ulcers were healed at a mean of five and one-half weeks (range, one to fourteen weeks). A deep infection developed in two patients during treatment. Twenty-two ulcers (31 per cent) recurred within eighteen months after initial healing; nineteen (86 per cent) of them healed after an average of two weeks in a second cast. Recurrent ulceration was usually associated with an underlying fixed deformity or osseous prominence. The total-contact cast provided safe, reliable, and cost-effective treatment for patients who had neuropathic ulcers of the foot.  相似文献   
12.
Thyroid function was evaluated in 13 consecutive patients with chronic myelogenous leukemia to verify in allogeneic bone marrow transplantation if the fractionated irradiation protocol with low dose rate, previously applied to reduce the damage to various organs, also prevents the 43% incidence of primary hypothyroidism that occurs after the administration of single dose with higher dose rate. Following bone marrow transplantation, decreased plasma levels of total thyroxine and triiodothyronine and impaired response of thyrotropic cells to thyrotropin-releasing hormone were observed. These alterations reverted to normal in nine months and none of the patients was hypothyroid at the end of follow-up. The damage to thyrotropic cells appears to be selective because the secretion of prolactin was not impaired and that of gonadotropins even increased, as a consequence of gonadal failure. Longer follow-up is needed to determine if this irradiation protocol, which prevents the complication of permanent primary hypothyroidism and does not cause any destruction of thyroid cells, may increase the risk of irradiation-related thyroid tumors.  相似文献   
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The age dependence of ATP hydrolase activity and oligomycin sensitive passive proton conduction in sonicated submitochondrial particles of rat brain and rat heart has been investigated. The results show an increase of Vmax of the ATP hydrolase activity and decrease of oligomycin sensitive passive proton conduction with increase of the age of rats from 3 to 6 months. Decrease of ATPase activity and increase of oligomycin sensitive proton conduction occur with further aging to 24 months. Immunoblot analysis shows that both the F(1) and F(0) contents of mitochondria vary with the age of rats, the former exhibiting relatively larger changes.  相似文献   
15.
Human herpesvirus 6 (HHV 6) has neurotropic and neuroinvasive properties. The virus has been found in the cerebrospinal fluid of many children with aseptic meningoencephalitis. Intrauterine transmission has been documented by HHV 6 DNA detection in cord blood specimens of apparently healthy newborns and in fetuses following spontaneous abortions. A patient is described with early neonatal afebrile seizures resulting from a congenital HHV 6 variant B infection disclosed by repeated detection of viral genome by polymerase chain reaction (PCR) in cerebrospinal fluid in the first days of life. At follow-up, magnetic resonance imaging (MRI) studies disclosed hyperintensities in the periventricular white matter and basal ganglia, associated with cerebral atrophy. Further follow-up at 18 months revealed poor neurological outcome with mild neurodevelopmental retardation, strabismus and hypertonia of legs. This report provides evidence of neurological involvement after HHV 6 vertical transmission, and the association with neurological sequelae.  相似文献   
16.
Vitamin E affects cell death in adult rat dentate gyrus   总被引:1,自引:0,他引:1  
We have previously reported the presence of dying cells in the granule cell layer (GCL) of adult rat dentate gyrus (DG), where neurogenesis occurs. In particular, we found that cell death in the GCL increased in vitamin E deficiency and decreased in vitamin E supplementation. These findings were regarded as related to changes in neurogenesis rate, which in turn was influenced by vitamin E availability; a neuroprotective effect of vitamin E on cell death was also proposed. In order to verify this latter hypothesis, we have studied cell death in all layers of DG in vitamin E-deficient and vitamin E-supplemented rats and in control rats at different ages, using TUNEL and nick translation techniques. The phenotype of TUNEL-positive cells was characterized and the existence of dying BrdU-positive cells was investigated. Dying cells with neuronal phenotype were observed throughout the DG in all experimental groups. The number of TUNEL-positive cells decreased from juvenile to adult age. A higher number of TUNEL-positive cells in vitamin E-deficient rats and a lower number in vitamin E-supplemented rats, with respect to age-matched controls, were found; moreover, in these groups, TUNEL-positive cells had a different percentage distribution in the different layers of the DG. Our results confirm the occurrence of cell death in DG, demonstrate that cell death affects neuronal cells and support the hypothesis that the effect of vitamin E on cell death is not related to neurogenesis.  相似文献   
17.
A major challenge in reconstructive surgery is flap ischemia, which might benefit from induction of therapeutic angiogenesis. Here we demonstrate the effect of an adeno-associated virus (AAV) vector delivering vascular endothelial growth factor (VEGF)165 in two widely recognized in vivo flap models. For the epigastric flap model, animals were injected subcutaneously with 1.5 x 10(11) particles of AAV-VEGF at day 0, 7, or 14 before flap dissection. In the transverse rectus abdominis musculocutaneous flap model, AAV-VEGF was injected intramuscularly. The delivery of AAV-VEGF significantly improved flap survival in both models, reducing necrosis in all treatment groups compared to controls. The most notable results were obtained by administering the vector 14 days before flap dissection. In the transverse rectus abdominis musculocutaneous flap model, AAV-VEGF reduced the necrotic area by >50% at 1 week after surgery, with a highly significant improvement in the healing process throughout the following 2 weeks. The therapeutic effect of AAV-VEGF on flap survival was confirmed by histological evidence of neoangiogenesis in the formation of large numbers of CD31-positive capillaries and alpha-smooth muscle actin-positive arteriolae, particularly evident at the border between viable and necrotic tissue. These results underscore the efficacy of VEGF-induced neovascularization for the prevention of tissue ischemia and the improvement of flap survival in reconstructive surgery.  相似文献   
18.
T-cell homeostasis is regulated by several molecules; among these, interleukin (IL)-7 plays an essential role in the survival and homeostatic proliferation of peripheral naive T cells. In a previous study, we investigated whether human mesenchymal stromal cells (MSCs) could be engineered with the IL-7 gene to produce functional level of this cytokine. In the present study, we analyzed the impact of different quantities of IL-7 produced by MSCs on the survival and proliferation of a negative immunoselected naive (CD3(+)/CD45RA(+)) T-cell population. Co-cultivation of peripheral naive T cells with MSCs producing low (16 pg/mL) or high (1000 pg/mL) IL-7 levels or in the presence of exogenous IL-7 (0.01 ng/mL and 100 ng/mL) maintained the CD3(+)/CD45RA(+) naive T-cell phenotype. Chemokine receptor CCR7(+) expression was also maintained among this T-cell population. Naive T-cell molecular characteristics were maintained as assessed by the Vbeta spectratyping complexity score, which showed the maintenance of a broad T-cell repertoire. No Th1 or Th2 differentiation was observed, as assessed by interferon-gamma or IL-4 accumulation. In contrast, only MSCs producing high amounts of IL-7 caused increased activation (CD25 31.2% +/- 12% vs 10% +/- 3.5%; P < .05), proliferation (CD71 17.8+/-7% vs 9.3%+/-3, P < .05), apoptosis (assessed by annexin V: 18.6% +/- 5% vs 14.9% +/- 2.6%; P > .05), and the phase S cell cycle (15% vs 6.9%, P > .05). Exogenous IL-7 exhibited no significant effect. In conclusion, we demonstrated that IL-7 produced by MSCs has a dose-independent effect on naive T-cell survival while exerting a dose-dependent effect on activation/proliferation. Due to the continuous production of IL-7 by engineered cells, our system is more efficacious than exogenous IL-7.  相似文献   
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20.
Several studies have shown a correlation between airborne pollutants and respiratory disorders. To determine whether professional exposure to industrial pollution might represent a risk factor for allergic respiratory diseases, we administered allergologic tests to 275 workers employed in a paper-making/printing factory and to a control population composed of 160 office workers from the same urban area. All subjects were evaluated on the basis of personal and family histories, the results of prick tests with common airborne allergens, specific serum IgE levels, pulmonary function test, and standard chest radiography. The percentage of subjects with allergies in the factory-worker group (67/275; 24.4%) was significantly higher than that observed among the office workers (20/160; 12.5%) (chi-square test: 8.17; P<0.01). Of the 67 factory workers with allergies, 94% had histories of daily exposure to aliphatic hydrocarbons. The results of this study indicate that exposure to the latter type of industrial pollutants is associated with a significantly higher prevalence of allergic respiratory diseases.  相似文献   
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