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31.
The objective of this study was to determine the Salmonella prevalence, the serotypes involved, and antimicrobial susceptibility patterns of Salmonella isolates recovered from fish, shrimp, lobster, and crab in Iran. A total of 384 samples of fish, shrimp, lobster, and crab were collected in three provinces along the Persian Gulf in the south coast of Iran. Samples were collected at the end of each month from September 2009 to May 2011. All samples were evaluated for the presence of Salmonella, stereotyped and tested for antimicrobial susceptibility. There was an overall Salmonella prevalence of 5%. Salmonella was isolated from a significantly larger number of fish (10.4%) than shrimp (1.8%; P?≤?0.05). No Salmonella was isolated from lobster and crab samples. Salmonella isolates recovered from fish and shrimp samples were of five different serotypes including Salmonella typhimurium, Salmonella enteritidis, Salmonel la typhi, Salmonella paratyphi B, and Salmonella newport. Susceptibilities of Salmonella isolates were determined for 12 antimicrobial drugs using the disk-diffusion method. Resistance to nalidixic acid was the most common finding (47.4%), followed by resistance to tetracycline (36.8%), streptomycin (15.8%), trimethoprim (15.8%), and ciprofloxacin (5.3%). To our best knowledge, this is the first study on prevalence of Salmonella in fish, shrimp, lobster, and crab and the first report on the isolation of Salmonella spp. from retail fish and shrimp in Iran.  相似文献   
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Milk is considered a nutritious food because it contains several important nutrients including proteins and vitamins. Conversely, it can be a vehicle for several pathogenic bacteria such as Staphylococcus aureus. The aim of the present study was to investigate the presence of classical enterotoxins of S. aureus in raw milk in Iran. For this purpose, from January 2011 to October 2011, a total of 88 raw milk samples from sheep (n?=?28), goat (n?=?27), camel (n?=?14), and water buffalo (n?=?19) were collected from 64 randomly selected herds in Isfahan, Chaharmahal va Bakhtiari, and Khuzestan provinces, Iran, and tested for staphylococcal enterotoxins (SEs) presence by enzyme-linked immunosorbent assay method. Out of 88 samples studied, 11 samples (12.5%) were positive for at least one SE. The prevalence rate of SEs contamination in raw sheep, goat, and water buffalo milk samples were 10.7%, 18.5%, and 15.8%. No classical SEs was founded from raw camel milk samples. Of these, four were positive for staphylococcal enterotoxin A (SEA), four for SEC, two SEA and SEC, and one for SEA and SED. None of the samples was positive for SEB and SEE. Statistical evaluation showed that there were no significant differences (P?>?0.05) between the presence of SEs raw sheep, goat, and water buffalo milk samples tested. The quality of Iranian milk is still low, and efforts from the government and the entire productive chain are required to attain consumer safety.  相似文献   
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The temporomandibular joint (TMJ) is a specialized synovial joint essential for the function of the mammalian jaw. The main components of the TMJ are the mandibular condyle, the glenoid fossa of the temporal bone, and a fibrocartilagenous disc interposed between them. The genetic program for the development of the TMJ remains poorly understood. Here we show the crucial role of sprouty (Spry) genes in TMJ development. Sprouty genes encode intracellular inhibitors of receptor tyrosine kinase (RTK) signaling pathways, including those triggered by fibroblast growth factors (Fgfs). Using in situ hybridization, we show that Spry1 and Spry2 are highly expressed in muscles attached to the TMJ, including the lateral pterygoid and temporalis muscles. The combined inactivation of Spry1 and Spry2 results in overgrowth of these muscles, which disrupts normal development of the glenoid fossa. Remarkably, condyle and disc formation are not affected in these mutants, demonstrating that the glenoid fossa is not required for development of these structures. Our findings demonstrate the importance of regulated RTK signaling during TMJ development and suggest multiple skeletal origins for the fossa. Notably, our work provides the evidence that the TMJ condyle and disc develop independently of the mandibular fossa.  相似文献   
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Introduction: There are some evidences indicating DNA damage by oxidant and mutant agents has an essential role in the chronic renal failure and end stage renal disease (ESRD). To investigate the possible association of GSTs variants with ESRD, we investigated the frequency of GST- T1, M1, and P1 genotypes, and the level of malondialdehyde (MDA) in patients with ESRD.

Materials and methods: The present case-control study consisted of 136 ESRD patients treated with maintenance hemodialysis and 137 gender- and age-matched, unrelated healthy controls from the population of west of Iran. The GST- T1, M1, and P1 genotypes were determined in all individuals using multiplex-PCR and PCR-RFLP. The level of MDA was measured by high-performance liquid chromatography (HPLC).

Results: We found that GSTM1 and GSTT1 null genotypes (GSTT1?/GSTM1?) increased the risk of ESRD by 1.8 times (p?<?0.001) and the increased risk of ESRD for GSTM-null (T1+-M1?) genotype was 3.04 times (p?=?0.002). ESRD patients carriers the GST (GSTM1-null?+?GSTT1-null?+?GST-null) genotypes compared to GST normal genotype increased the risk of ESRD by 3.3 (p?<?0.001) times. ESRD patients carriers of GST-null, GSTM1-null, and GSTT1-null genotypes had greater MDA concentration compared with the same genotypes of control subjects. Our results indicated that the GST-null allele (GSTT1-null/GSTM1-null) is a risk factor for ESRD and carriers of this allele have high levels of MDA.

Conclusion: Our findings indicate that oxidative stress, impairment of the antioxidant system and abnormal lipid metabolism may play a role in the pathogenesis and progression of ESRD and its related complications. These data suggest that patients with ESRD are more susceptible to vascular diseases.  相似文献   
38.
BACKGROUND: Traditional doses of depot GnRH agonist may be excessive for ovarian stimulation. We compared half-dose depot triptorelin (Group I) with reduced-dose daily buserelin (Group II) in a long protocol ICSI/embryo transfer through a double-blind randomized clinical trial. METHODS: Controlled ovarian stimulation (COS) was started by a pretreatment with oral contraceptives for 21 days. Then, 182 patients were randomized into two groups of 91. Group I received 1.87 mg triptorelin depot i.m. followed by daily s.c. injections of saline. Group II (reduced-dose protocol) received a bolus injection of i.m. saline followed by daily s.c. injections of 0.5 mg buserelin, which was then reduced to 0.25 mg at the start of human menopausal gonadotrophin stimulation. When transvaginal ultrasound showed at least two follicles of 16-20 mm diameter, HCG was given and ICSI was performed 40-42 h later. RESULTS: No significant differences were seen in the mean (SD) number of follicles at HCG administration, as our primary outcome [10.3 (4.4) in Group I versus 11.1 (4.2) in Group II, P = 0.180, mean difference = 0.86, 95% confidence interval 0.39-2.11]. The other early results of COS, clinical and ongoing pregnancy rates, or early pregnancy loss were also not significantly different between the groups. Group I endured longer stimulation period [11.2 (1.8) days versus 10.6 (1.9), P = 0.030]. CONCLUSIONS: Clinical outcomes were not significantly different between Group I and Group II.  相似文献   
39.
This study was designed to survey the incidence of Enterococcus faecalis infection in symptomatic and asymptomatic root canals of necrotic teeth using PCR and to isolate the bacterium for further screening. Sixty patients categorized according to their clinical symptoms were used for sampling by insertion of paper points into the root canals and absorbing all the fluids present within them. The samples were incubated in 1.0 ml 2xYT (containing 16 g bacto tryptone, 10 g yeast extract and 5.0 g NaCl per liter) for 24 h at 37 degrees C without aeration prior to multiplex PCR analysis. To assist the isolation of E. faecalis, sub-samples were further grown in the same medium supplemented with 6.5% NaCl and back-inoculated into bile esculin. Using multiple cultivation-dependent and PCR analyses, 6 cases (10%) of E. faecalis were identified. Four isolates were obtained from asymptomatic cases of chronic apical periodontitis, and the other two were associated with phoenix abscess and acute apical abscess, respectively. No E. faecalis infection was found in 5 patients with acute apical periodontitis or in 9 with chronic suppurative periodontitis. Our results indicate that there is no significant difference in the incidence of E. faecalis between symptomatic and asymptomatic necrotic dental root canals (P > 0.05).  相似文献   
40.

Background

Colitis, a colonic inflammatory condition, showed a linkage with hepatobiliary disorders such as cirrhosis. It has been reported that both endogenous opioids and nitric oxide (NO) play critical roles in colitis pathogenesis. Moreover, opioid and NO levels showed elevation in patients with cirrhosis. The aim of this study was to evaluate the effect of cirrhosis on the experimental model of colitis and the possible involvement of opioidergic/nitrergic systems in rats.

Methods

Colitis was induced by acetic acid 28 days after bile duct ligation (BDL). L-NAME, as an inhibitor of NO synthase and naltrexone, as an antagonist of opioid receptors were administered intraperitoneally to animals during 3 days after induction of colitis. Macroscopic colitis lesion area, inflammatory mediators change, NO metabolite levels, and colon microscopic injuries were assessed 3 days after induction.

Results

Cirrhosis significantly reduced the severity of damages to the colon. Administration of L-NAME (10 mg/kg), naltrexone (10 mg/kg) and co-administration of L-NAME (1 mg/kg) and naltrexone (5 mg/kg) significantly decreased the protective effect of BDL on colitis. Nitrite elevated levels in BDL rats were significantly diminished in L-NAME- and naltrexone-treated animals. Histopathology parameters and cytokines level alterations in the colon of acetic acid-treated animals after BDL was reversed after injection of L-NAME, naltrexone, and co-administration of L-NAME (1 mg/kg) + naltrexone (5 mg/kg).

Conclusion

Cirrhosis improved the intestinal damages induced by acetic acid in rats which may be mediated through interaction of nitrergic and opioidergic systems.  相似文献   
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