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This study aimed to examine the side effects of selected neonicotinoids (Acetamiprid, Aceta, and Imidacloprid, Imid) on Oreochromis niloticus juveniles. The acute toxicity, Probit method, revealed an LC50 of 195.81 and 150.76 ppm for Aceta/96 h and Imid/72 h respectively. The fish were divided into three groups that were exposed, for 21 days (n?=?5/replicate), to 1/10 of the LC50 of either neonicotinoids, however, the third was an unexposed control group. Results of erythrocytic micronucleus (MN), and nuclear abnormalities (NA) showed that Aceta and Imid exposure caused a significant (p?<?0.05) increase in MN by?~?2.2 and?~?10 folds, respectively relative to control. NAs occurred at the order of kidney-shaped?>?budding?>?binucleated in Aceta, however, budding?>?binucleated?>?kidney-shaped was noticed in the Imid group. Histopathological changes in gills, liver, and muscles were observed significantly in both exposed groups with more severity in the Imid group. Collectively, Aceta and Imid have potential genotoxicity and histopathological alterations in O. niloticus.

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Soft tissue chondroma is an uncommon soft-tissue cartilaginous tumor of benign nature, it considers a variant of extra-skeletal chondromas that undergoes extensive ossification. This case of a 37?years old Egyptian male presented with a recurrent slowly growing painful palpable heel mass arises at the plantar aspect of his RT foot.The case is pathologically proven to be benign soft tissue chondroma.  相似文献   
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Nevirapine (NVP) therapy is associated with a high risk of serious liver injury and skin rash. Treatment of Brown Norway rats with NVP causes an immune-mediated skin rash. Even though NVP does not cause serious liver injury in wildtype animals, incubation of hepatocytes with NVP leads to the release of presumably danger-associated molecular pattern molecules (DAMPs), which activate macrophages. In this study, we examined the liver biopsies of Brown Norway rats treated with NVP to determine the histologic correlate to the release of DAMPs by hepatocytes. In vivo, debris from necrotic hepatocytes and endothelial cells were present in the liver sinusoids, a condition that can trigger an immune response. In addition to mitochondrial, hepatocytic, and endothelial damage, the drug induced large hepatocytic inclusions composed of lipid droplets surrounded by concentric whorls of smooth endoplasmic reticulum (SER) cisternae—lipid-SER (LSER) inclusions, which were deposited in the sinusoids. NVP is lipid soluble, and these LSER inclusions may be sinks of NVP or its metabolites. LSERs are deposited in the blood stream where they may be picked up by lymph nodes and contribute to initiation of an immune response leading to serious liver injury or skin rash. LSERs migration from liver to the blood stream may signify a novel mechanism of drug exocytosis.  相似文献   
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Nicotine administration has been shown to increase the risk for cardiovascular diseases and death. The present study was designed to investigate the impact of nicotine administration on serum level tumor necrosis factor and cycloxygenase -2 (COX-2) expression mediated cardiac injury in rat off springs, and the possible protective effect of folic acid. Eighteen pregnant female rats were randomly divided into three groups, six animals each. Control group received the vehicle, nicotine group received a dose of nicotine 0.1?mg/kg body weight, daily with subcutaneous injection from day 3 of gestation until weaning on postnatal day 21. Nicotine treated group received daily oral supplementation with folic acid 200?mg/kg body weight by intragastric tube prior to injection of nicotine. In serum of the pups, levels of tumor necrosis factor (TNF), nitric oxide (NO), total antioxidant capacity (TAC) and malondialdehyde (MDA) were measured. Histopathological studies of cardiac tissues using hematoxylin-eosin (H&E) were carried out. The expression of COX-2 was evaluated using immunohistochemistry. Serum TNF and MDA were significantly increased, while serum NO and TAC were significantly decreased in nicotine group. Moreover, nicotine-exposed rats showed complete lysis of cardiac myocytes, marked cytoplasmic vacuolation of myocytes, muscle fibers show loss of striation and increased COX-2 expression. Concomitant folic acid administration resulted in a significant alleviation of biochemical and structural alteration-induced by nicotine. In conclusion, folic acid has a protective role against nicotine induced cardiac injury by reduction of COX-2 expression, decreasing TNF production and lipid peroxidation mediated cell injury.  相似文献   
6.
Hydroferrate fluid, MRN-100, an iron-based compound derived from bivalent and trivalent ferrates, is a potent antioxidant compound. Therefore, we examined the protective effect of MRN-100 against γ-radiation-induced lethality and damage to hematopoietic tissues in fish. A total of 216 Nile tilapia fish (Oreochromis niloticus) were randomly divided into four groups. Group 1 served as a control that was administered no radiation and no MRN-100 treatment. Group 2 was exposed only to γ-radiation (15 Gy). Groups 3 and 4 were pre-treated with MRN-100 at doses of either 1 ml/l or 3 ml/l in water for 1 week, and subsequently exposed to radiation while continuing to receive MRN-100 for 27 days. The survival rate was measured, and biochemical and histopathological analyses of hematopoietic tissues were performed for the different treatment groups at 1 and 4 weeks post-radiation. Exposure to radiation reduced the survival rate to 27.7%, while treatment with MRN-100 maintained the survival rate at 87.2%. In addition, fish exposed to γ-radiation for 1 week showed a significant decrease in the total number of white blood cells (WBCs) and red blood cells (RBCs) series. However, treatment with MRN-100 protected the total WBC count and the RBCs series when compared with irradiated fish. Furthermore, significant histological lesions were observed in the hepatopancreas, spleen and gills of irradiated fish. However, treatment with MRN-100 protected the histopathology of various organs. We conclude that MRN-100 is a radioprotective agent in fish and may be useful as an adjuvant treatment to counteract the adverse side effects associated with radiation exposure.  相似文献   
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The present study was undertaken to evaluate the potential risks of the mucolytic and broncholytic drug, Theophylline derivatives (Mucophylline) maternally administered on the pups. The nursing rats orally administered from 1st postpartum day (PPD) to 21th PPD with two different doses 30.83 mg/kg (low dose) and 66.61 mg/kg (Human equivalent dose (HED)). On the 21th PPD, the postnatal developmental signs, skeletal malformation and the histopathology of neonatal liver, kidney and brain were examined. Our results showed that Mucophylline induced a significant reduction in the neonatal weight and length, delayed, weak and incomplete ossification, wavy ribs and the neonatal liver revealed histopathological changes, pyknotic hepatocytes, cytoplasmic vacuolization, dilated sinusoid and necrotic area. Kidney revealed alternation changes, enlargement of the glomerulus, renal tubules degeneration and lymphatic infiltration. Brain (cerebral cortex and cerebellum) showed neurodegenerative changes, vacuolization of neuropil, congested and dilated blood vessel and dark stain neurons. Our results showed that the activities of non-enzymatic (GSH) and enzymatic (GST, CAT) antioxidants were insignificantly decrease in both neonatal brain and liver tissues of rats administered with 30.83 mg/kg and 61.66 mg/kg of Mucophylline and insignificant increase in MDA levels in both neonatal brain and liver tissues. However, significant reduction (P  0.05) in the content of GR was recorded in neonatal brain tissue of rats administered with 30.83 mg/kg and 61.66 mg/kg of Mucophylline during lactation period in comparison with control. These support and proof the potential risks of the maternal administration of Mucophylline on pups.  相似文献   
10.
Metabolic Brain Disease - Stroke is a lethal event with a high incidence in Egypt. Quick early intervention can be lifesaving. Transient global ischemia (TGI), a type of ischemic stroke, is mainly...  相似文献   
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