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31.
Chronic shortage of donor organs has led to acceptance of steatotic livers as grafts, although there is a higher risk of primary graft dysfunction. We herein report the beneficial impact of Polysol, a newly developed preservation solution, on cold storage of steatotic rat livers. Dietary hepatic steatosis was induced in Wistar rats by 2-day fasting and subsequent 3-day re-feeding with a fat-free, carbohydrate-rich diet. Fatty livers were retrieved, flushed and then stored at 4 degrees C for 24 hours with either HTK or Polysol. Functional integrity of the grafts was evaluated by isolated reperfusion with oxygenated Krebs-Henseleit buffer at 37 degrees C for 45 minutes in both groups. Polysol preservation resulted in significant reductions of not only parenchymal (AST (IU/L); 6728+/-824 in HTK vs. 3107+/-718 in Polysol; P < 0.001) but also mitochondrial (GLDH (IU/L); 3189+/-773 vs. 1282+/-365; P < 0.01) enzyme release throughout reperfusion. Moreover, PVP (16.9+/-2.7 vs. 7.8+/-1.5 mmHg; P < 0.05), hepatic O2 consumption (0.291+/-0.047 vs. 1.056+/-0.053 micromol/g liver/min; P < 0.001), tissue ATP content (0.695+/-0.086 vs. 1.340+/-0.157 micromol/g dry-liver; P < 0.005), bile production (0.79+/-0.11 vs. 4.08+/-0.66 microL/g liver/45-min; P < 0.001), malondialdehyde into the perfusate (1.922+/-0.198 vs. 0.573+/-0.094 nmol/L; P < 0.0001) and wet/dry-weight ratio of the liver tissues (5.20+/-0.31 vs. 3.85+/-0.15; P < 0.005) were all better preserved by Polysol. In line with these benefits, electron microscopy revealed that Polysol preservation substantially suppressed deleterious mitochondrial alterations in steatotic livers. In conclusion, cold storage using Polysol resulted in significantly better integrity and function of steatotic livers. Polysol, therefore, may be a new alternative especially for "marginal" organs.  相似文献   
32.
OBJECTIVE: To assess the safety and efficacy of anticholinergics in men with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH) by a systematic review of published reports and a meta-analysis of the reported outcomes. METHODS: We searched Medline, Embase and Cochrane databases (1966-2006), and hand-searched relevant reference lists and conference proceedings, for studies on the use of anticholinergics in men with BPH or bladder outlet obstruction. Eligible studies were assessed for quality and foreign language studies were translated. We collected data on all reported outcomes, conducted meta- analyses on the maximum urinary flow rate (Q(max)), postvoid residual urine volume (PVR) and volume at first contraction, and calculated the acute urinary retention (AUR) rate. We used sensitivity analysis to confirm the findings. RESULTS: We identified five randomized controlled trials (RCTs) and 15 observational studies. Four RCTs incorporating 633 patients were included in the meta-analyses. Anticholinergics did not significantly alter Q(max) (0.1 mL/s, 95% confidence interval, CI, 0.6-0.7). The PVR was increased by 11.6 mL (95% CI 4.5-18.6) although there was no significant difference between AUR rates. The total International Prostate Symptom Scores (IPSS) were not significantly different, but there were improvements for IPSS storage subscores in one RCT. The AUR rate was 0.3% at the 12-week follow-up in 365 men in the RCTs and observational studies. CONCLUSION: Anticholinergic use in men with LUTS suggestive of BPH appears to be safe. Further studies are required to establish efficacy with a suitable precision.  相似文献   
33.
A prospective, randomized study was performed in an ovine model to compare the efficacy of an anorganic bovine-derived hydroxyapatite matrix combined with a synthetic 15 amino acid residue (ABM/P-15) in facilitating lumbar interbody fusion when compared with autogenous bone harvested from the iliac crest. P-15 is a biomimetic to the cell-binding site of Type-I collagen for bone-forming cells. When combined with ABM, it creates the necessary scaffold to initiate cell invasion, binding, and subsequent osteogenesis. In this study, six adult ewes underwent anterior-lateral interbody fusion at L3/L4 and L4/L5 using PEEK interbody rings filled with autogenous bone at one level and ABM/P-15 at the other level and no additional instrumentation. Clinical CT scans were obtained at 3 and 6 months; micro-CT scans and histomorphometry analyses were performed after euthanization at 6 months. Clinical CT scan analysis showed that all autograft and ABM/P-15 treated levels had radiographically fused outside of the rings at the 3-month study time point. Although the clinical CT scans of the autograft treatment group showed significantly better fusion within the PEEK rings than ABM/P-15 at 3 months, micro-CT scans, clinical CT scans, and histomorphometric analyses showed there were no statistical differences between the two treatment groups at 6 months. Thus, ABM/P-15 was as successful as autogenous bone graft in producing lumbar spinal fusion in an ovine model, and it should be further evaluated in clinical studies.  相似文献   
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35.
BACKGROUND AND AIMS: Ischemically damaged donor livers are prone to graft non-function. This can in part be explained by a suboptimal wash-out during procurement. An enriched machine perfusion (MP) preservation solution for livers, named Polysol, was developed. The aim of this study was to investigate the type of flush solution, temperature and anticoagulant content on the wash-out of the non-heart-beating donor (NHBD) rat liver. METHODS: Rat livers were flushed after 30 min warm ischemia. After excision, livers were reperfused at 37 degrees C, with analysis of damage and function, concerning (1) solutions (University of Wisconsin (UW), histidine-tryptophan-ketoglutarate (HTK) and Polysol); (2) temperature (4 degrees C, 18 degrees C and 37 degrees C); (3) addition of heparin and (4) wash-out followed by 24 h MP. RESULTS: (1) Reperfusion results were inferior in the UW group; (2) less damage and improved function were seen after wash-out using Polysol at 37 degrees C; (3) No effects were seen of the addition of heparin to Polysol; (4) MP after wash-out using HTK resulted in more liver damage and decreased liver function as compared with wash-out using Polysol. CONCLUSIONS: Polysol is applicable as a flush solution for the NHBD liver, resulting in equal to better wash-out as compared with UW and HTK. The best temperature for this NHBD wash-out is 37 degrees C.  相似文献   
36.
37.

Objectives

Urine microscopy is a common test performed in emergency departments (EDs). Urine specimens can easily become contaminated by different factors, including the collection method. The midstream clean-catch (MSCC) collection technique is commonly used to reduce urine contamination. The urine culture contamination rate from specimens collected in our ED is 30%. We developed an instructional application (app) to show ED patients how to provide a MSCC urine sample. We hypothesized that ED patients who viewed our instructional app would have significantly lower urine contamination rates compared to patients who did not.

Methods

We prospectively enrolled 257 subjects with a urinalysis and/or urine culture test ordered in the ED and asked them to watch our MSCC instructional app. After prospective enrollment was complete, we retrospectively matched each enrolled subject to an ED patient who did not watch the instructional app. Controls were matched to cases based on gender, type of urine specimen provided, ED visit date and shift. Urinalysis and urine culture contamination results were compared between the matched pairs using McNemar's test.

Results

The overall urine culture contamination rate of the 514 subjects was 38%. The majority of the matched pairs had a urinalysis (63%) or urinalysis plus urine culture (35%) test done. There were no significant differences in our urine contamination rates between the matched pairs overall or when stratified by gender, by prior knowledge of the clean catch process or by type of urine specimen.

Conclusion

We did not see a lower contamination rate for patients who viewed our instructional app compared to patients who did not. It is possible that MSCC is not effective for decreasing urine specimen contamination.  相似文献   
38.
The distribution of the Anopheles gambiae complex of malaria vectors in Africa is uncertain due to under-sampling of vast regions. We use ecologic niche modeling to predict the potential distribution of three members of the complex (A. gambiae, A. arabiensis, and A. quadriannulatus) and demonstrate the statistical significance of the models. Predictions correspond well to previous estimates, but provide detail regarding spatial discontinuities in the distribution of A. gambiae s.s. that are consistent with population genetic studies. Our predictions also identify large areas of Africa where the presence of A. arabiensis is predicted, but few specimens have been obtained, suggesting under-sampling of the species. Finally, we project models developed from African distribution data for the late 1900s into the past and to South America to determine retrospectively whether the deadly 1929 introduction of A. gambiae sensu lato into Brazil was more likely that of A. gambiae sensu stricto or A. arabiensis.  相似文献   
39.
40.
Objectives

The aim of this study was categorizing the microbial flora and susceptibility to antibiotics and to clarify to which degree the empiric administered antibiotics are suitable for therapy.

Materials and methods

A 3.5-year retrospective study evaluated hospital records of 206 patients who suffered from head and neck infections of odontogenic origin. All patients underwent surgical incision and drainage and received intravenous antibiotics and inpatient treatment. The specimens were obtained by performing a swab.

Results

Two hundred six patients were included with 251 strains isolated (1.22 per patient). One hundred eight strains showed antibiotic resistance. Eighty-seven patients showed at least one bacterial strain that showed antibiotic resistance (42.2%). The most frequent isolated bacteria were Streptococcus spp. (n = 116), with a high rate of antibiotic resistance (50.8%). We investigated 205 cases of antibiotic resistance in 87 subjects. Nine bacterial strains showed no susceptibility to unacid (4.3%) and 36 strains to clindamycin (17.5%).

Conclusion

Antibiotic resistance against clindamycin was rather high. The distribution of the afflicted spaces and isolated bacteria was alike recent findings. It is mandatory to understand that immediate surgical treatment in terms of incision and drainage is the basis in abscess treatment. Antibiotic treatment is adjunct therapy.

Clinical relevance

Streptococcus species were the most frequently identified bacteria presenting antibiotic resistance in more than 50%. Increased resistant rates for clindamycin require reconsiderations regarding an empiric antibiotic treatment.

  相似文献   
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