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1.
目的 分析腹部超声联合阴道灌注0.9%氯化钠对幼女阴道异物的诊断价值。方法 回顾性分析2018年1月—2021年12月就诊于赣州市妇幼保健院妇科的102例疑似阴道异物幼女临床资料。患儿均接受经腹部超声、阴道灌注0.9%氯化钠检查。以宫腔镜诊治结果作为金标准,分析经腹部超声单独检测或腹部超声联合阴道灌注0.9%氯化钠诊断阴道异物的准确性、有效性。结果 宫腔镜结果显示,患儿中阴道炎有21例(20.59%),阴道异物有81例(79.42%),其中棉絮状物、谷物、头发丝等线状物最为常见;单独诊断、联合诊断出阴道异物分别有69例和79例,与宫腔镜诊断结果的K值分别为0.689和0.897。将宫腔镜诊断结果作为金标准,单独诊断、联合诊断阴道异物的敏感性分别为0.765(95% CI:0.594,0.816)、0.951(95% CI:0.826,0.995),特异性分别为0.667(95% CI:0.563,0.786)、0.905(95% CI:0.795,0.972),准确度分别为0.745(95% CI:0.586,0.813)、0.941(95% CI:0.817,0.984),单独诊断、联合诊断的敏感性、特异性、准确度可信区间无重叠,说明有统计学意义。结论 阴道灌注0.9%氯化钠可增强幼女阴道异物在超声下的显影,提升诊断准确性、有效性,且操作简单、损伤小,起到清洁阴道作用。  相似文献   
2.
《药学学报(英文版)》2020,10(5):799-811
Overexpression of adenosine triphosphate (ATP)-binding cassette subfamily G member 2 (ABCG2) in cancer cells is known to cause multidrug resistance (MDR), which severely limits the clinical efficacy of chemotherapy. Currently, there is no FDA-approved MDR modulator for clinical use. In this study, rociletinib (CO-1686), a mutant-selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), was found to significantly improve the efficacy of ABCG2 substrate chemotherapeutic agents in the transporter-overexpressing cancer cells in vitro and in MDR tumor xenografts in nude mice, without incurring additional toxicity. Mechanistic studies revealed that in ABCG2-overexpressing cancer cells, rociletinib inhibited ABCG2-mediated drug efflux and increased intracellular accumulation of ABCG2 probe substrates. Moreover, rociletinib, inhibited the ATPase activity, and competed with [125I] iodoarylazidoprazosin (IAAP) photolabeling of ABCG2. However, ABCG2 expression at mRNA and protein levels was not altered in the ABCG2-overexpressing cells after treatment with rociletinib. In addition, rociletinib did not inhibit EGFR downstream signaling and phosphorylation of protein kinase B (AKT) and extracellular signal-regulated kinase (ERK). Our results collectively showed that rociletinib reversed ABCG2-mediated MDR by inhibiting ABCG2 efflux function, thus increasing the cellular accumulation of the transporter substrate anticancer drugs. The findings advocated the combination use of rociletinib and other chemotherapeutic drugs in cancer patients with ABCG2-overexpressing MDR tumors.  相似文献   
3.

Background

Various investigations have reported that the internal mammary artery (IMA) is an efficient and functional choice of conduit for vascular graft surgeries, especially for coronary artery bypass grafts; however, the quest to find an ideal vascular substitute remains. We hypothesized that acellular IMA could be an appropriate graft for small-diameter vascular bypasses that could be used in various surgeries including coronary artery bypass grafting.

Methods

We decellularized human IMAs and performed histologic evaluations and scanning electron microscopy to confirm the decellularization process and the preservation of the extracellular matrix. Subsequently, we grafted the scaffolds into the superficial femoral arteries of 8 New Zealand rabbits with an end-to-end anastomosis. Computed tomography angiograms were provided at 3, 12, and 36 months postoperatively. Subsequently, the animals were killed, and biopsies were taken for histologic and immunohistochemical assessments.

Results

Evaluation of the acellular tissue confirmed the efficacy of the decellularization protocol and the preservation of the extracellular matrix. All 8 animals survived the entire follow-up period. Doppler ultrasonography and computed tomography angiographies verified the conduit's patency. Histologic assessments depicted the recellularization of all 3 layers of the scaffold. Smooth muscle cells were detected in tunica media. Immunohistochemical assessments confirmed these findings.

Conclusions

In conclusion, we demonstrated that acellular human IMA could be used as an efficient small-diameter vascular substitute with high patency. These findings could pave the path for future investigations on the clinical application of acellular IMA as a novel vascular graft for small-diameter bypass surgeries.  相似文献   
4.
柽柳属(Tamarix chinensis L.)植物,为多年生泌盐盐生植物,是一类重要灌木植物,具有许多独特的生物、生态学特征。本研究以刚毛柽柳(T.hispida Wild)和长穗柽柳(T.elongata Ledeb)为研究对象,采用盆栽实验,开展耐盐性实验:中性盐NaCl设置0、50、100、150和200 mmoL/L 5个浓度水平,通过测定盐胁迫下两种柽柳的光合速率、蒸腾速率、游离脯氨酸含量、干重等生理指标,结果显示:刚毛柽柳和长穗柽柳均表现出较强的耐盐能力,但刚毛柽柳受NaCl胁迫的影响较小,表明刚毛柽柳耐盐性强于长穗柽柳,可作为柽柳属植物耐盐生理和分子机制研究的备选材料。  相似文献   
5.

Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
6.
7.
The metastasis of cervical cancer has always been a clinical challenge. We investigated the effects of low-dose naltrexone (LDN) on the epithelial mesenchymal transition of cervical cancer cells in vitro as well as its influence on macrophage polarization and associated cytokines in vivo. The results suggested that LDN supressed the proliferation, migration and invasion abilities and promote their apoptosis in Hela cells, whereas the opioid growth factor receptor (OGFr) silenced significantly reversed these effects in vitro. Knockdown the expression of OGFr, the inhibitory of LDN on EMT was weakened. LDN could inhibit cervical cancer progression in nude mice. In additon, LDN indirectly reduced the number of tumor-associated macrophages (TAMs), mainly M2 macrophages, and decreased expression of anti-inflammatory factor IL-10 in the serum of nude mice. These findings demonstrate that LDN could be a potential treatment for cervical cancer.  相似文献   
8.
BackgroundAs an ongoing worldwide health issue, Coronavirus disease 2019 (COVID–19) has been causing serious complications, including pneumonia, acute respiratory distress syndrome (ARDS), and multi-organ failure. However, there is no decisive treatment approach available for this disorder, which is primarily attributed to the large amount of inflammatory cytokine production. We aimed to identify the effects of Nano-curcumin on the modulation of inflammatory cytokines in COVID-19 patients.MethodForty COVID-19 patients and 40 healthy controls were recruited and evaluated for inflammatory cytokine expression and secretion. Subsequently, COVID-19 patients were divided into two groups: 20 patients receiving Nano-curcumin and 20 patients as the placebo group. The mRNA expression and cytokine secretion levels of IL-1β, IL-6, TNF-α and IL‐18 were assessed by Real‐time PCR and ELISA, respectively.ResultOur primary results indicated that the mRNA expression and cytokine secretion of IL-1β, IL-6, TNF-α, and IL-18 were increased significantly in COVID-19 patients compared with healthy control group. After treatment with Nano-curcumin, a significant decrease in IL-6 expression and secretion in serum and in supernatant (P = 0.0003, 0.0038, and 0.0001, respectively) and IL-1β gene expression and secretion level in serum and supernatant (P = 0.0017, 0.0082, and 0.0041, respectively) was observed. However, IL-18 mRNA expression and TNF-α concentration were not influenced by Nano-curcumin.ConclusionNano-curcumin, as an anti-inflammatory herbal based agent, may be able to modulate the increased rate of inflammatory cytokines especially IL-1β and IL-6 mRNA expression and cytokine secretion in COVID-19 patients, which may cause an improvement in clinical manifestation and overall recovery.  相似文献   
9.
PurposeTo retrospectively investigate incidence, clinical outcome, and risk factors of iatrogenic pleural effusion in patients with hepatic tumors undergoing radiofrequency (RF) ablation using artificial ascites (AA).Materials and MethodsPatients (N = 163) who underwent RF ablation using AA were classified into pleural effusion and non–pleural effusion groups according to the presence of pleural effusion on immediate follow-up CT and chest radiograph after RF ablation. The pleural effusion group included asymptomatic and symptomatic subgroups. The incidence and subsequent clinical outcomes of patients developing pleural effusion after RF ablation were evaluated.ResultsOverall, 96 patients (58.9%) developed pleural effusion, which resolved in 4.4 d ± 3.1. Hospital length of stay in the pleural effusion group was longer than the non-pleural effusion group (6.5 d ± 2.6 vs 5.7 d ± 2.8, P < .01). The pleural effusion group had longer AA infusion time (P = .01), larger infused AA volume (P < .01), and longer ablation time (P < .01) than the non-pleural effusion group. Eighteen patients (18.8%) developed symptomatic pleural effusion and had a larger infused AA volume than asymptomatic patients with pleural effusion (P < .01). Pleural effusion duration and hospital length stay were also longer in the symptomatic pleural effusion subgroup than in the asymptomatic subgroup (P < .01). Infused AA volume was the only independent prognostic factor of pleural effusion duration in multivariate analysis (P = .038).ConclusionsPleural effusion frequently occurs after RF ablation using AA. Although generally considered negligible, pleural effusion could be a clinical problem and prolong hospitalization. Therefore, operators should be careful not to infuse too much AA when performing RF ablation.  相似文献   
10.
PurposeTo investigate if high-frequency irreversible electroporation (H-FIRE) treatments can be delivered at higher voltages and with greater energy delivery rates than currently implemented in clinical irreversible electroporation protocols.Materials and MethodsTreatments using 3,000 V and 5,000 V were administered to mechanically perfused ex vivo porcine liver via a single applicator and grounding pad (A+GP) as well as a 4-applicator array (4AA). Integrated energized times (IET) 0.01–0.08 seconds and energy delivery rates 25–300 μs/s were investigated. Organs were preserved at 4°C for 10–15 hours before sectioning and gross analysis using a metabolic stain to identify the size and shape of ablation zones.ResultsA+GP ablations measured between 1.6 cm and 2.2 cm, which did not increase when IET was increased from 0.02 seconds to 0.08 seconds (P > .055; range, 1.9–2.1 cm). Changes in tissue color and texture consistent with thermal damage were observed for treatments with energy delivery rates 50–300 μs/s, but not for treatments delivered at 25 μs/s. Use of the 4AA with a 3-cm applicator spacing resulted in ablations measuring 4.4–4.9 cm with energy delivery times of 7–80 minutes.ConclusionsH-FIRE treatments can rapidly and reproducibly create 2-cm ablations using an A+GP configuration. Treatments without thermal injury were produced at the expense of extended treatment times. More rapid treatments resulted in ablations with varying degrees of thermal injury within the H-FIRE ablation zone. Production of 4-cm ablations is possible using a 4AA.  相似文献   
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