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排序方式: 共有1291条查询结果,搜索用时 15 毫秒
91.
Over the past several years, the numerous contamination incidents have raised concerns over the presence of halogenated aromatic hydrocarbons, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and related chemicals in foods and feeds. Here we applied a sensitive recombinant mouse hepatoma cell (H1L1.1c2) bioassay for the determination of dioxins and dioxin-like polychlorinated dibenzofurans (PCDFs) and biphenyls (PCBs) in meat and animal feeds. These cells responded to TCDD-like chemicals with dose-dependent induction of firefly luciferase activity, and the minimal detection limit of TCDD in the cell was 16 fg. Induction equivalency factors determined for pure TCDD-like polychlorinated dibenzo-p-dioxins (PCDDs), PCDFs, and PCBs in the bioassay were well-correlated with the World Health Organization's toxic equivalency factors. To determine the applicability of the bioassay system to detect those compounds presence in meat and feed samples, cell bioassays for 17 TCDD-like PCDDs and PCDFs congeners-spiked lipid extracted from beef or animal feed were performed. Mean recoveries of TCDD-like chlorinated PCDDs and PCDFs congeners from spiked beef or feed fat ranged from 61.2 to 122.3%. Within-laboratory coefficients of variation for analysis as index of precision were lower than 5.2%, and the calculated limits of detection and quantitation were 0.33 and 1 pg toxicity equivalency quantity (TEQ)/0.5 g fat, respectively. Correlation between bioassay- and high-resolution gas chromatography-mass spectrometry (HR-GC-MS)-determined TEQs for 10 meat samples was 0.85, with 1.2 times higher in bioassay than HR-GC-MS. The correlation between bioassay- and HR-GC-MS-determined TEQs in 10 animal feed products was 0.81, with 2.1 times higher in bioassay than HR-GC-MS. Overall, these results demonstrated that the recombinant cell bioassay can be used for the rapid detection and quantitation of PCDDs and dioxin-like PCDFs and PCBs in meats and animal feeds. 相似文献
92.
Simon G 《Orvosi hetilap》2005,146(33):1733-1736
Renovascular disease is defined as renal insufficiency secondary to fibromuscular or atherosclerotic renal artery stenosis. The immediate cause of renal insufficiency is not hypertension but ischemia and hyper-reninaemia that result from critical (greater than 80%) renal artery stenosis. Hyper-reninaemia damages also the contra lateral non-ischemic kidney. The key to successful treatment of renovascular disease is its diagnosis before the onset of renal insufficiency (> 180-200 micromol/l serum creatinine). The goal of interventional therapy is the prevention of symptomatic renal insufficiency and end-stage renal failure; the indication for intervention is the presence of greater than 80-85% renal artery stenosis. Patients diagnosed with non-critical renal artery stenosis (< 80%) do not need immediate intervention, only close follow-up. 相似文献
93.
Parikh JR Gokani VN Doctor PB Kulkarni PK Shah AR Saiyed HN 《American journal of industrial medicine》2005,47(6):494-499
BACKGROUND: An epidemiological study was undertaken in Gujarat, India to study the acute and chronic health effects of occupational exposure to green tobacco. METHODS: Non-Flue Cured Virginia (FCV) tobacco is the main crop in many districts of Central Gujarat. Three villages were selected from Anand district for the study and a random sample of 685 exposed workers were examined. Six hundred and fifty-five control workers with the same socio-economic status were examined from two villages where tobacco was not cultivated. RESULTS: The overall prevalence of green tobacco sickness (GTS) was 47.0% among tobacco workers. The prevalence in women workers was 55.7% while in men workers it was 42.66%. To detect the chronic health effects prevalence of hypertension, electrocardiogram (ECG) abnormalities, and eye problems in all the workers and reproductive abnormalities in women workers, all subjects received a medical examination. The data were compared in exposed and control group but they were non-significant statistically. No case of tobacco amblyopia was detected. CONCLUSION: The prevalence of GTS among non-FCV tobacco workers is high. However, from viewpoint of severity it can be considered as mild acute nicotine toxicity, which is relieved without medication. No significant difference is observed as regards to chronic health effects among tobacco workers and control workers. 相似文献
94.
Manganese-induced early biochemical changes and effects of supplementation of magnesium nitrate (Mg(NO3)2) and antioxidant vitamins (A, C, D and E) were studied in rats intoxicated with manganese. Significant elevation in the level of chlorides in plasma, erythrocytes, liver and cerebellum, and a decrease in plasma inorganic phosphate (pi) with an increase in liver pi were observed in animals exposed to manganese as compared to controls. The level of erythrocyte-acid labile phosphate (ALP), nicotinamide adeninedinucleotide (NAD+) and plasma sialic acid (N-acetylneuraminic acid, NANA) also increased significantly. Elevated levels of chlorides in plasma, erythrocytes and cerebellum reversed to normal control values whereas liver chlorides restored partially by the supplementation of Mg(NO3)2. Vitamins supplementation was effective to reverse chlorides level in erythrocytes, liver and cerebellum. Decreased level of pi in plasma and the highly elevated level of erythrocyte ALP were also recovered in animals received Mg(NO3)2 in addition to MnSO4. However, such effect of Mg(NO3)2 was not seen in lowering the elevated level of NANA that restored by the administration of vitamins. Thus, the early alterations in plasma levels of chlorides, pi, and NANA and erythrocyte-ALP seem to be an indicative of early manganese toxicity while Mg(NO3)2 and vitamins supplementation appear to provide, at least in part, protection against manganese toxicity. 相似文献
95.
Thrombo-embolic episodes are an uncommon but known complication of nephrotic syndrome. However, pulmonary thrombosis/thromboembolism is rare, especially in children. We describe the cases of two girls, aged 12 years, who presented with severe oedema in relapse. They had intermittent tachypnoea, and CT pulmonary angiography (CTPA) provided a less invasive and more definitive way of confirming pulmonary thrombosis/thromboembolism. They received heparin with resolution of the tachypnoea. Anticoagulation was continued for 6 months after the episode in one patient. They have been in remission for more than 1 year, and a thrombophilia screen does not indicate a predisposing tendency to the formation of clots. Pulmonary thrombosis/thromboembolism could present with subtle symptoms and needs prompt diagnosis and treatment to prevent a fatal outcome. 相似文献
96.
A. Jothi Ph.D. U. Seetaram Ph.D. M. V. R. Reddy M.D. O. S. Reddi Ph.D. P. P. Reddy Ph.D. 《Indian journal of pediatrics》1982,49(4):629-630
A rare anomaly of tryptophan catabolism was detected in a 5 year old hindu boy, during a search for amino acid disorders in
mental retardation 相似文献
97.
Development and maturation of nuclear groups in the mammillary complex of second and third trimester human fetal hypothalamus were studied using Nissl stain, galanin immunocytochemistry and transmission electron microscopy. While the identity of the supra and medial mammillary nucleus was established at 24 weeks of gestation (w.g.) in Nissl stained preparation, galanin immunoreactive (Gal-ir) neurons were seen in the supra and medial mammillary nucleus of 27 through 39 w.g. fetuses. Immunoreactive perikarya in the lateral mammillary nucleus appear later at 34 w.g. and show relatively meager population. Gal-ir neurons of the supramammillary nucleus were divisible in dorsal and ventral subgroups. There was a progressive increase in galanin expressing neurons in more and more ventral positions, along the medial margin of either mammillary body so that in term fetal specimens, the ventral subgroup appeared to be continuous with the medial mammillary nucleus. Galanin positive neurons were relatively sparse in the core of the mammillary bodies. Transmission electron micrographs revealed neurons with varying degree of indentation of the nuclear envelope. Vigorous synaptogenesis was seen in the supramammillary region of the mammillary bodies. The height and width of the synaptic complex also showed a progressive increase. Although galanin neurons were reported from the supramammillary nucleus of adult human mammillary complex, no immunoreactivity was detected in the medial and lateral components of the mammillary body. We suggest that expression of galanin in the medial and lateral components may be of transient occurrence and may serve a significant role in the synaptogenesis. 相似文献
98.
Sinha R 《Indian pediatrics》2004,41(12):1213-1217
99.
3-mercapto-5-(3,4-dihydroxyphenylazo-1')-1,2,4-triazole (METRIAP), 3-mercapto-5-(2,4-dihydroxy-3-carboxyphenylazo-1)-1,2,4-triazole (METRIAREZ-gamma) and 2-mercapto-5-(2,4-dihydroxy-5-carboxyphenylazol-)-1,3,4-thiadiazole (METIDAREZ-beta), reagents synthesized in the Department of Medicinal Chemistry of Medical University in Lublin, have been used to determine Fe(II) and Zn(II) in Materna, Centrum, H-Pantoten pharmaceutical multivitamin preparations, containing other trace elements. Zn (II) with METRIAREZ-gamma at pH=7.35, and Fe(II) with METRIAP and METIDAREZ-beta at pH=10.30 or 7.40 constitute soluble in H2O colourful chelate compound at a mole ratio of 1:2 and 1:3, respectively. Volume stability constant of Fe(II) and Zn(II) complexes is equal to log K(METRIAP-Fe(II)) = 16.46; log K(METRIAREZ-beta-Fe(II)) = 14.253; log K(METRIAREZ-gammaZn(II)) = 11.47. Fe(III) and Zn(II) solutions were obtained by wet mineralisation of Materna, Centrum and H-Pantoten preparations with concentrated H2SO4 and 30% H2O2 added. Spectrophotometric determination was carried out in an aqueous-methanolic solution environment. Statistically evaluated results were compared with the results of the AAS (atomic absorption spectrophotometry) determination method. Advantages of the Fe(II) and Zn(II) determination method are its precision RSD = 0.23%-2.09% and repeatability as well as the possibility of Fe(II) determination without the necessity of masking or separating other trace elements. 相似文献
100.
Patel PS Shah MH Jha FP Raval GN Rawal RM Patel MM Patel JB Patel DD 《Indian journal of cancer》2004,41(1):25-31
BACKGROUND: The changes in lipid profile have long been associated with cancer because lipids play a key role in maintenance of cell integrity. AIMS: The present study evaluated alterations in plasma lipid profile in untreated head and neck cancer patients as well as patients with oral precancerous conditions (OPC) and its association with habit of tobacco consumption. MATERIAL AND METHODS: This hospital-based case control study included 184 head and neck cancer patients, 153 patients with OPC and 52 controls. Plasma lipids including: (i) Total cholesterol, (ii) LDL cholesterol (LDLC), (iii) HDL cholesterol (HDLC) (iv) VLDL cholesterol (VLDLC) and (v) triglycerides were analysed by spectrophotometric kits. STATISTICAL ANALYSIS USED: Student's t-test was performed to compare mean values of the parameters. RESULTS: A significant decrease in plasma total cholesterol and HDLC was observed in cancer patients (P=0.008 and P=0.000 respectively) as well as in patients with OPC (P=0.014 and P=0.000, respectively) as compared to the controls. The plasma VLDL and triglycerides levels were significantly lower in cancer patients as compared to the patients with OPC (P=0.04) and controls (P=0.059). The tobacco habituates showed lower plasma lipid levels than the non-habituates. Our data strengthen the evidence of an inverse relationship between plasma lipid levels and head and neck malignancies as well as OPC. CONCLUSION: The lower levels of plasma cholesterol and other lipid constituents in patients might be due to their increased utilization by neoplastic cells for new membrane biogenesis. The findings strongly warrant an in-depth study of alterations in plasma lipid profile in head neck cancer patients. 相似文献