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81.
目的探讨蚕蛹浆(silkworm larvae plasma,SLP)比色法在关节假体周围感染(periprosthetic joint infection,PJI)精准诊断中的应用价值。方法取90只健康雄性新西兰大白兔,采用Swanson假体行膝关节置换手术;然后根据致病菌不同随机分为3组:A组(金黄色葡萄球菌组)、B组(表皮葡萄球菌组)及C组(大肠埃希菌组),每组30只。术后第3天膝关节腔内注射1 mL不同浓度致病菌制备PJI模型。分别于接种菌液前及接种后7、14、21 d取样进行检测,参照2018年PJI费城国际共识诊断标准首先判定并计算3组实验动物的造模成功率,并采用SLP比色法计算其在PJI精准诊断中的敏感性、特异性、阳性预测值、阴性预测值和诊断效率。结果接种菌液21 d时,A、B、C组分别有26、18、23只实验动物诊断为感染,造模成功率分别为86.7%、60.0%、76.7%,3组间比较差异无统计学意义(χ^(2)=5.724,P=0.073)。PJI比色法结果显示,A组在7 d时出现1只假阳性动物(特异性75.0%),随时间推移(14、21 d)SLP的特异性升至100.0%;14、21 d,另出现了1只假阴性动物(敏感性由100.0%降至96.2%)。B组在7 d时出现1只假阳性动物(特异性91.7%),随着时间推移特异性回升至100.0%;在14、21 d时分别出现1只和4只假阴性动物(敏感性分别为94.4%及83.3%)。C组在7 d时有2只假阳性动物(特异性71.4%),随后回升至100.0%。A、C组在21 d时诊断效率极高(96.7%和100.0%);即使面对B组低毒力的表皮葡萄球菌,21 d时SLP的诊断效率也可保持在90.0%;总体诊断效率很好(95.6%)。结论 SLP比色法诊断PJI具有较高的敏感性、特异性以及诊断效率,是一种极具潜能的PJI诊断方法。  相似文献   
82.
83.
Long-term consumption of high-fat and high-calorie foods not only causes obesity, but also may cause a decline in sperm quality in men. Rats with abnormal lipid metabolism (high-fat rats) were established by high-fat diet for 24 weeks. HE staining was used to observe the morphological changes of testis in rats, TUNEL and flow cytometer was used to detect the cell apoptosis in rat testis and in vitro. Immunohistochemistry and Western blotting were used to detect the expression of protein. After 24 weeks of high-fat food feeding, the body weight, serum lipids and number of apoptotic spermatogenic cells in the high-fat group rat were significantly higher than those in the control group. In vivo, the expression of HSP60 protein in testis of high-fat rats was positive related to apoptosis of spermatogenic cells, cleaved caspase 3/caspase 3 protein expression and Bax/Bcl2 protein expression in testis of high-fat rats. Proportion of apoptotic spermatogenic cells was increased by up-regulation of HSP60 protein expression in vitro. Long-term consumption of high-fat diets can cause high expression of HSP60 and spermatogenic cells apoptosis in rats, while HSP60 over-expression promotes spermatogenic cell apoptosis and MAPK signal pathway in vitro.  相似文献   
84.
This study aimed to evaluate growth factor concentration in platelet-rich plasma (PRP) (leukocyte-rich PRP) based on storage temperature, duration of storage, and method of activation. PRP samples were stored at 24℃ (room temperature group), 4℃ (refrigerator group), and −70℃ (deep-freezer group). In each temperature, four aliquots were prepared based on the time of analysis (immediately, 1, 3, and 7 days after preparation). After storage, concentrations of platelet-derived growth factor-AA (PDGF-AA), transforming growth factor-β (TGF-β), vascular endothelial growth factor (VEGF), insulin-like growth factor-1 (IGF-1), and fibroblast growth factor-basic (FGF-B) were assessed with/without activation using Quantikine colorimetric sandwich immunoassay kits. PRP was activated with 10% Triton-X for PDGF-AA, VEGF, FGF-B, IGF-1 measurement and sonication for TGF-β1 measurement. Without activation, PDGF-AA concentration was highest on day 7 in the room temperature group. With activation, the concentration of PDGF-AA was constant over the observation period at all temperatures. Without activation, the TGF-β1 concentration remained negligible over the observation period at all temperatures. However, with activation, TGF-β1 gradually increased to its highest concentration on day 7 at all temperatures. Over the observation period, VEGF and IGF-1 concentrations were constant with and without activation at all temperatures. Without activation, FGF-B concentration increased, with the highest concentration observed on day 7 in the deep-freezer group. With activation, FGF-B concentration decreased after day 1 in the room temperature group. Growth factor concentration in PRP differed significantly based on storage temperature, duration of storage, and method of activation. Appropriate storage conditions and activation are important to optimize its effects on desired clinical outcomes. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:777-784, 2020  相似文献   
85.
目的比较血小板裂解液(PL)与富血小板血浆(PRP)关节腔内注射治疗膝骨关节炎(KOA)的临床疗效。 方法采用前瞻性随机对照研究的方法,选取2012年4月至2015年9月山东省文登整骨医院收治的150例KOA患者的150膝,通过随机数字表法分为血小板裂解液(PL)组、富血小板血浆(PRP)组和玻璃酸钠(HA)组(每组50例),3组关节腔注射PL、PRP和HA频次为每周1次,连续5周。选择治疗前、治疗后1、3、6个月为时间观察点,西安大略和麦克马斯特大学(WOMAC)疼痛评分、Lequesne肿胀评分及WOMAC综合评分评价治疗前后关节疼痛、肿胀情况及综合功能等方面的区别,同时记录3组病例在治疗过程中不良反应发生情况并进行比较。Fisher精确检验、方差分析或t检验用于数据分析比较。 结果PL组49例,PRP组48例,HA组47例成功完成治疗及6个月以上随访。3组患者在治疗后1个月时WOMAC疼痛评分最低;治疗后3及6个月比较,PL组与PRP组低于HA组(3个月:t=1.115,P<0.01;t=2.343,P<0.05;6个月:t=0.463,P<0.05;t=1.983,P<0.01),PL组与PRP组比较,差异无统计学意义(t=3.123、2.983,均为P>0.05)。Lequesne肿胀评分在治疗后3个月时PL组低于PRP组与HA组(t=3.132,P<0.05;t=1.545,P<0.01),PRP组低于HA组(t=2.654,P<0.05)。治疗后6个月时,PL组与PRP组均低于HA组(t=2.513,P<0.05;t=3.313,P<0.01),PL组与PRP组比较差异无统计学意义(t=2.343,P>0.05)。3组治疗完成后WOMAC综合评分比较:治疗后3个月PL组低于PRP组与HA组(t=2.442,P<0.05;t=2.415,P<0.01),PRP组低于HA组(t=1.324,P<0.01);治疗6个月比较,PL组与PRP组低于HA组(t=1.613,P<0.05;t=2.913,P<0.01),PL组与PRP组比较差异无统计学意义(t=3.413,P>0.05)。不良反应发生率的比较中,PL组不良反应发生率(2.0%)低于HA组(8.5%)(P<0.05);PL组低于PRP组(P>0.05),PRP组低于HA组(P>0.05),但差异均无统计学意义。 结论血小板裂解液治疗膝骨关节炎能够取得与富血小板血浆同样的治疗效果,均优于玻璃酸钠,同时不良反应发生率低。  相似文献   
86.
Proteasome inhibitor–based strategies hold promise in transplant but have yielded varying results. Carfilzomib, a second‐generation proteasome inhibitor, may possess advantages over bortezomib, the first‐generation proteasome inhibitors. The purpose of this study was to evaluate the safety, toxicity, and preliminary efficacy of carfilzomib in highly HLA‐sensitized kidney transplant candidates. Renal transplant candidates received escalating doses of carfilzomib followed by plasmapheresis (group A) or an identical regimen with additional plasmapheresis once weekly before carfilzomib dosing. Thirteen participants received carfilzomib, which was well tolerated with most adverse events classified as low grade. The safety profile was similar to bortezomib desensitization; however, neurotoxicity was not observed with carfilzomib. Toxicity resulted in permanent dose reduction in 1 participant but caused no withdrawals or deaths. HLA antibodies were substantially reduced with carfilzomib alone, and median maximal immunodominant antibody reduction was 72.8% (69.8% for group A, P = .031, 80.1% for group B, P = .938). After depletion, rebound occurred rapidly and antibody levels returned to baseline between days 81 and 141. Bone marrow studies revealed that approximately 69.2% of plasma cells were depleted after carfilzomib monotherapy. Carfilzomib monotherapy–based desensitization provides an acceptable safety and toxicity profile while leading to significant bone marrow plasma cell depletion and anti‐HLA antibody reduction.  相似文献   
87.
88.
Background: Platelet‐rich plasma (PRP) contains a number of biologically active growth factors, and previous studies have reported conflicting ridge augmentation results. The primary aim of this randomized, controlled, masked, clinical trial was to determine if PRP combined with a rapidly resorbing cancellous allograft would enhance the regenerative result compared with an allograft without PRP. Methods: Thirty‐two patients with an edentulous ridge defect were sequentially entered into the study; four were excluded from data analysis. Fourteen patients received a cancellous allograft (CAN group) and the other 14 received a cancellous allograft mixed with PRP (PRP group). All 28 grafted sites were covered with a resorbable polylactide membrane. After elevation of a full‐thickness flap, horizontal ridge dimensions were measured with a digital caliper at the crest and 5 mm apical to the crest. Vertical ridge dimensions were measured from a tooth‐supported stent. All sites were reentered at 4 months, and a trephine core was obtained for histologic analysis before implant placement. Results: The crestal ridge width for the CAN group had a mean gain of 2.0 ± 1.2 mm, whereas the PRP group gained 2.9 ± 1.0, and the difference was statistically significant between groups (P <0.05). The percent vital bone was 36% ± 14% for the CAN group compared with 51% ± 15% for the PRP group and was statistically significant between groups (P <0.05). Loss of augmented ridge width was 34% ± 17% for the CAN group and 28% ± 17% for the PRP group (P >0.05). Conclusion: These clinical and histologic findings suggest that PRP enhanced bone regeneration and resulted in increased horizontal bone gain and percentage vital bone.  相似文献   
89.
Bile acids (BAs) traversing the enterohepatic circulation exert several important metabolic effects. Their hepatic synthesis, controlled by the enzyme cholesterol 7alpha-hydroxylase (CYP7A1), has a unique diurnal variation in man. Here we provide evidence that the transintestinal flux of BAs regulates serum levels of intestinal fibroblast growth factor 19 (FGF19) that in turn modulate BA production in human liver. Basal FGF19 levels varied by 10-fold in normal subjects, and were reduced following treatment with a BA-binding resin and increased upon feeding the BA chenodeoxycholic acid. Serum FGF19 levels exhibited a pronounced diurnal rhythm with peaks occurring 90-120 min after the postprandial rise in serum BAs. The FGF19 peaks in turn preceded the declining phase of BA synthesis. The diurnal rhythm of serum FGF19 was abolished upon fasting. We conclude that, in humans, circulating FGF19 has a diurnal rhythm controlled by the transintestinal BA flux, and that FGF19 modulates hepatic BA synthesis. Through its systemic effects, circulating FGF19 may also mediate other known BA-dependent effects on lipid and carbohydrate metabolism.  相似文献   
90.
Glutamate may play an important role in the pathogenesis of migraine: glutamate release in the brain may be involved in the development of spreading depression and increased concentrations of this amino acid have been reported in plasma and platelets from migraine patients. Here we assessed platelet glutamate uptake and release in 25 patients affected by migraine with aura (MA) and 25 patients affected by migraine without aura (MoA), comparing the results with a group of 20 healthy matched controls. Both glutamate release from stimulated platelets and plasma concentrations of the amino acid were assessed by high-performance liquid chromatography, and were increased in both types of migraine, although more markedly in MA. Platelet glutamate uptake, assessed as 3H-glutamate intake, was increased in MA, while it was reduced in MoA with respect to the control group. These results support the view that MA might involve different pathophysiological mechanisms from MoA and, specifically, up-regulation of the glutamatergic metabolism. Understanding these dysfunctional pathways could lead to new, possibly more successful therapeutic approaches to the management of migraine.  相似文献   
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