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991.
Based on the reports of 18 fever related deaths in Bhojpur Primary Health Centre (PHC) of Moradabad District (UP), a study was undertaken during September and October, 2000 to explore the possibility of outbreak of malaria in the area and the reasons of the outbreak. The slide positivity rate (SPR) and slide falciparum rate (SFR) in active fever surveys were found to be 84.7% and 82.2% respectively. Among children the average enlarged spleen and spleen rate were 1.9 and 27.4 per cent respectively. The mortality rate of Anopheles culicifacies in DDT, Malathion and Deltamethrin was 42.5, 86.7 and cent per cent respectively. The results of the study revealed that the outbreak was of malaria with predominance of Plasmodium falciparum causing several deaths in the affected villages. The investigation revealed that there was disruption of surveillance and supervision of malaria activities.  相似文献   
992.
A 12-year-old boy is described with bilateral radial club hands, scoliosis, hypospadias, isolated dextrocardia, hypoplastic ribs, an ectopic kidney and spina bifida occulta. Although some of the clinical features of this patient are seen in VATER association and sacrococcygeal dysgenesis, the presence of dextrocardia, facial dysmorphism, radial, renal and vertebral anomalies preclude these diagnoses.  相似文献   
993.
994.
Neurological disorders following acute or chronic exposure to pesticides have been reported in a number of human cases. However, the mechanism(s) by which pesticides produce central nervous system dysfunction is not clear. The objective of the present study was to examine the functional status of blood-brain barrier (BBB) in rats and mice exposed to selected pesticides of different chemical groups. Adult male albino rats and mice were exposed (1/10 of LD50) daily to dichlorvos (organophosphate), lindane (organochlorine) and carbofuran (carbamate) through oral intubation for 3 days. The status of BBB was evaluated by determining brain sodium fluorescein dye uptake and brain uptake index (BUI) in relation to serum dye level. The brain dye uptake and BUI in pesticide-exposed rats did not differ significantly in comparison to that of controls. However, brain dye uptake and BUI were increased significantly in mice exposed to dichlorvos (85%, 40%), lindane (79%, 26%) and carbofuran (129%, 61%). The results of this study show that mouse BBB system is more sensitive to pesticide-induced breach as compared to that of rat. These variations may have a role in determining the outcome of pesticide neurotoxicity in different species.  相似文献   
995.
OBJECTIVES: Oxidative stress is considered to be a unifying link between diabetes mellitus (DM) and its complications including nephropathy. The aim of the present study was to evaluate oxidative stress status in Asian Indian patients of type 2 DM with nephropathy. DESIGN AND METHODS: Serum levels of malondialdehyde (MDA) and nitric oxide end products (nitrite and nitrate), activities of erythrocyte superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH) content were estimated in controls, patients of type 2 DM without nephropathy (group 1) and with nephropathy (group 2). RESULTS: Serum MDA concentration was significantly high in both the groups of diabetic patients as compared to controls, (p < 0.05), with group 2 having a significantly higher value than group 1 (p < 0.05). Significantly elevated serum nitrite levels were found in diabetic patients as compared to controls (p < 0.001), however, no significant difference was found between group 1 and group 2. Moreover, serum nitrate as well as nitrite + nitrate levels were significantly higher in group 2 as compared to controls (p < 0.05). Activity of erythrocyte SOD and CAT was significantly reduced in both groups as compared to controls (p < 0.001) with catalase activity in group 2 being significantly lower than group 1 (p < 0.05). Erythrocyte GSH content was significantly lower in group 2 as compared to controls (p < 0.05) and group 1 (p < 0.05). CONCLUSIONS: Results of the present study indicate that oxidative stress is increased and antioxidant defenses are compromised in type 2 DM. These derangements are of a higher magnitude in patients of type 2 DM with nephropathy.  相似文献   
996.
997.
BACKGROUND: The incidence of the cancers of the oral cavity, pharynx, esophagus and larynx in different population groups of India is amongst the highest reported in Asian countries. There is evidence that high dietary carotenoids and vitamin C may possibly decrease the risk of laryngeal cancer. Limited data is available from India on the association between these micronutrients and the risk of laryngeal cancer. AIMS: To assess the levels of vitamin A, vitamin C and zinc in laryngeal cancer patients and healthy controls. SETTING AND DESIGN: A hospital based case- control study. MATERIAL AND METHODS: One hundred and fifty five laryngeal cancer patients and a control group of 155 healthy individuals constituted the study population. Individuals in the control group were individually matched with the patients for their age +/- 2 years, sex and place of residence. Venous blood was drawn from the cases and controls and estimations of vitamin A, zinc and vitamin C was done utilizing the standard procedures. STATISTICAL ANALYSIS USED: Paired 't' test to compare the mean serum levels of vitamin A and zinc and plasma vitamin C between laryngeal cancer patients and controls. Univariate logistic regression analysis to calculate the odds ratios and the confidence intervals. RESULTS: The mean serum vitamin A, zinc and plasma vitamin C levels were significantly lower in laryngeal cancer patients as compared to the controls. CONCLUSIONS: The findings of the present study indicated a strong association of these micronutrients with laryngeal cancer in the Indian population.  相似文献   
998.
The purpose of this study was to examine the potential use of electrolytes to control naproxen sodium (I) release from chitinosan (II) tablets. An ANOVA was employed to evaluate the effects of molecular weight (MW) of II, electrolyte valence (EV), and pH of the dissolution medium on I's release. The intrinsic dissolution rates and saturation solubilities of I were determined at each of the pHs used. Directly compressed tablets were prepared from admixtures containing: I, NaCl, CaCl(2), or AlCl(3), Mg stearate, and II. The tablets were characterized for their dimensions, crushing strengths, friability, disintegration times, and in vitro dissolution profiles. The slopes of the log-log cumulative percent released-time curves (t=0-5 h) were compared using ANOVA. Based on the ANOVA, each of the variables-chitinosans, EVs, and pHs-significantly affected drug release (P<0.05). Besides the poor aqueous solubility of I, the factors possibly affecting drug release included: (a) the formation of a rate-limiting II gel barrier; (b) the interaction of I with ionized amino groups of II; (c) the effect of electrolyte on the II's gel barrier formation; and/or (d) decreased aqueous solubility of I in the presence of electrolyte.  相似文献   
999.
Retinoids reverse potentially malignant lesions and inhibit the development of second primary tumors in oral cancer patients by binding to nuclear retinoid receptors. Alterations in the expression of retinoid receptor-alpha are implicated in tumor progression. Herein, we hypothesized that increased expression of RARalpha protein in oral squamous cell carcinoma (SCC) is associated with a poor clinical outcome and thus may serve as a prognostic factor. Retrospective immunohistochemical analysis of RARalpha protein expression was carried out in paraffin-embedded tissue sections from 115 patients with completely resected oral SCCs for whom clinical follow-up data were available. Increased expression of RARalpha protein was observed in 67/115 (58%) oral SCCs (weakly positive in 38 patients and strongly positive in 29 patients). Kaplan-Meier analysis showed that patients with RARalpha positivity had significantly shorter disease-free survival time (median time 40 months vs. 86 months, p = 0.0229). Furthermore, disease-free survival time of the 29 patients with strongly positive RARalpha was significantly worse than for the 86 patients with weak or undetectable levels of RARalpha (p = 0.0328). Strong RARalpha expression in oral SCCs was associated with a significantly worse disease-free survival, suggesting that RARalpha may serve as a prognostic indicator of poor clinical outcome. Further studies are warranted to determine its utility in identifying the subset of patients who would benefit from use of retinoids as adjuvant in chemotherapy or chemopreventive approaches.  相似文献   
1000.
The molecular mechanisms involved in tumor progression from a low-grade astrocytoma to the most malignant glioblastoma multiforme (GBM) have been hampered due to lack of suitable experimental models. We have established a model of tumor progression comprising of two cell lines derived from the same astrocytoma tumor with a set of features corresponding to low-grade glioma (as in HNGC-1) and high-grade GBM (as in HNGC-2). The HNGC-1 cell line is slowgrowing, contact-inhibited, nontumorigenic, and noninvasive, whereas HNGC-2 is a rapidly proliferating, anchorage-independent, highly tumorigenic, and invasive cell line. The proliferation of cell lines is independent of the addition of exogenous growth factors. Interestingly, the HNGC-2 cell line displays a near-haploid karyotype except for a disomy of chromosome 2. The two cell lines express the neuronal precursor and progenitor markers vimentin, nestin, MAP-2, and NFP160, as well as glial differentiation protein S100β. The HNGC-1 cell line also expresses markers of mature neurons like Tuj1 and GFAP, an astrocytic differentiation marker, hence contributing toward a more morphologically differentiated phenotype with a propensity for neural differentiation in vitro. Additionally, overexpression of epidermal growth factor receptor and c-erbB2, and loss of fibronectin were observed only in the HNGC-2 cell line, implicating the significance of these pathways in tumor progression. This in vitro model system assumes importance in unraveling the cellular and molecular mechanisms in differentiation, transformation, and gliomagenesis.  相似文献   
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