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21.
两种术式治疗多囊卵巢综合征的远期疗效追踪比较   总被引:1,自引:0,他引:1  
[目的]评价开腹卵巢楔形切除(OWR)和腹腔镜下双侧卵巢电灼开窗术(LOD)两种术式对多囊卵巢综合征(PCOS)的远期疗效.[方法]1981至2001年在我院诊断为PCOS并接受手术治疗的妇女共151例,其中行OWR 61例、LOD 90例,追踪分析两组妇女术后妊娠率、术后妊娠时间的分布及术前后月经模式变化.[结果]两组的临床特征具有可比性,OWR组累积妊娠率84%,LOD组累积妊娠率72%,两组间没有明显差异,绝大部分妊娠发生在术后18个月内;OWR组术后3个月、半年、1年、3年、5年及10年月经规律的妇女所占的比例分别是81.3%、81.3%、77.3%、77.6%、78.9%、85.2%,明显高于术前的31.1%(P值<0.05);LOD组术后3个月、半年、1年、3年、5年及10年月经规律的妇女所占的比例分别是80.6%、63.5%、56.7%、58.0%、57.6%、42.9%,明显高于术前的35.6%(P值<0.05);术后OWR组月经规律妇女占的比例明显高于LOD组(P均<0.05).[结论]两种术式的术后妊娠率相似.OWR比LOD更好、更长远地改善PCOS妇女的月经异常.  相似文献   
22.
BACKGROUND: Breast milk contains many immunomodulatory factors (soluble CD14 (sCD14), IgA and cytokines) with the potential to influence infant immune development. OBJECTIVE: To determine if changes in breast milk omega-3 polyunsaturated fatty acid (n-3 PUFA) composition as a result of maternal dietary fish oil supplementation during pregnancy can modify levels of these immunological parameters in breast milk. METHOD: In a randomized controlled trial, 83 atopic women received either 4 g fish oil capsules (containing 3.7 g n-3 PUFA) (n = 40) or 4 g olive oil capsules (n = 43) from 20 weeks gestation until delivery. Breast milk was collected 3 days post-partum and fatty acids were analysed by gas liquid chromatography and IgA, sCD14 and cytokines (IL-5, IL-6, IL-10, TNF-alpha and IFN-gamma) were quantitated by ELISA or time resolved fluorescence (TRF). RESULTS: Omega-3 docosahexaenoic acid (DHA; 22:6n-3) and eicosapentaenoic acid (EPA; 20:5n-3) levels were significantly higher (P < 0.001) in breast milk from women supplemented with fish oil (n = 33, DHA mean 1.15%, SD 0.47% and EPA mean 0.16%, SD 0.07%) than in samples from the control group (n = 40, DHA mean 0.50%, SD 0.17% and EPA mean 0.05%, SD 0.02%). Breast milk arachidonic acid (AA; 20:4n-6) levels were significantly lower (P = 0.045) in the fish oil group (mean 0.55%, SD 0.12%) compared with the control group (mean 0.61%, SD 0.14%). Breast milk IgA was positively correlated with DHA (P = 0.046) and 22:5n-3 (P = 0.003), but inversely correlated with linoleic acid (LA; 18:2n-6) (P=0.034). Levels of sCD14 were also positively correlated with 22:5n-3 (P=0.009). Cytokines involved in IgA synthesis (IL-10 and IL-6) were also significantly correlated with both IgA and n-3 PUFA levels, although there were no differences in the levels of breast milk IgA, sCD14 or cytokines between study groups. CONCLUSION: Supplementation with fish oil during pregnancy significantly alters early post-partum breast milk fatty acid composition. omega-3 PUFA levels were positively associated with IgA and sCD14 levels, suggesting a relationship between fatty acid status and mucosal immune function.  相似文献   
23.
Background: Gastrointestinal strictures are the most often and serious complication in Crohn's disease. Because of the frequent postoperative recurrence in Crohn's disease, endoscopic therapy of gastrointestinal stricture is one of the best therapeutic options. Method: The present study sets out the results from a prospective study of endoscopic dilation therapy on 48 Crohn's disease patients with severe gastrointestinal stenoses. All patients who could not undergo endoscopic balloon dilation therapy (EBD) were operated on. Results: Long‐term success was attained in 32 of the 48 patients; cumulative avoidance of surgery after EBD was 86% at one year and 71% at three. Second, the most hazardous factor was recurrent inflammation causing restenosis. Patients who had strictures with oral luminal dilatation and patients with frequent recurrence had a tendency to be operated on. As a complication, perforation occurred in two cases (3.3%). Conclusions: EBD therapy for Crohn's stricture in the gastrointestinal tract is recommended before surgical intervention.  相似文献   
24.
田径运动员心缩间期的研究   总被引:4,自引:0,他引:4  
<正> 近年来在运动医学领域中,心缩间期(STI)被认为是评定运动员心脏功能状况的指标之一。为了进一步探讨STI对于评定田径运动员的心脏功能状况的意义,我们进行了下列研究。  相似文献   
25.
大隐静脉曲张微创外科治疗   总被引:5,自引:0,他引:5  
目的 总结外科微创方法治疗大隐静脉曲张的经验。方法 采用大隐静脉高位结扎微创剥脱术治疗 465例 ( 5 72条患肢 )及静脉腔内激光治疗 6例 ( 7条患肢 )下肢静脉曲张患者。结果 在 471例患者中 ,随访到 42 7例 ,随访率 90 .7% ,平均随访时间 3 .8年。结果显示手术创伤小、并发症少、复发率低 ( 1.41% )。结论 此两种微创手术操作简单、合理、易于掌握 ,且疗效理想 ,值得推广。  相似文献   
26.
Eighty of 89 patients who underwent radical resection (resectability 89.9%) for carcinoma of the papilla of Vater between 1976 and 1992 were retrospectively reviewed. Seventy-three patients underwent pancreaticoduodenectomy (PD) and 7 underwent pylorus-preserving pancreaticoduodenectomy (PPPD). The postoperative mortality rate was only 3.8% (3 patients). The 3- and 5-year survival rates were 63.6% and 57.4%, respectively. Important factors influencing long-term survival were Stage (clinical stage = Stage), microscopic lymph node metastasis (n), duodenal wall invasion (d), vascular invasion (v), and the epithelium of origin. Early carcinoma of the papilla of Vater is defined as tumor in which invasion is limited within the papilla of Vater; in particular, carcinomatous invasion is within the muscle of Oddi (d0) with n0. PD and/or PPPD with radical lymph node dissection should be performed for carcinoma of the papilla of Vater, as these procedures can be performed with low morbidity and mortality.  相似文献   
27.
RNA干扰(RNAi)技术及其在功能基因组学研究中的应用   总被引:12,自引:0,他引:12       下载免费PDF全文
近年来的研究表明 ,一些小的双链RNA可以高效、特异的阻断体内某些基因致使mRNA降解 ,诱使细胞表现出特定基因缺失的表型 ,称为RNA干扰 (RNAinterference ,RNAi)。由于可以作为代替基因敲除的遗传工具 ,RNAi技术正在改变着功能基因组学 (functionalgenomics)领域的研究步伐。《科学》杂志和美国科学促进会将RNAi技术评选为2 0 0 2年十大重大科学成就之首。1 RNAi及其作用机制1.1 RNAi回顾首次发现双链RNA (doublestrandRNA ,dsR NA)能够导致基因沉默的现象来源于对线虫Caenorhabditiselegans的研究。1995年 ,康乃尔大学的…  相似文献   
28.
Inanimate structures cannot detect and repair their fatigue damage or microdamage, so to minimize it they need more structural material and strength. Living bone handles this matter differently. Bone modeling drifts adapt bone architecture and strength to the loads on bones in ways that tend to keep strains from exceeding a “modeling threshold” range. Strains (or equivalent features) above that threshold switch mechanically controlled modeling ON. Where strains stay below that threshold, this modeling goes OFF. Repeatedly loading-deloading a bone causes microdamage in it, and basic multicellular unit (BMU)-based bone remodeling normally repairs it. Where strains stay below an operational “microdamage threshold,” remodeling can repair whatever microdamage happens for as long as it happens. Strains above that threshold can cause too much microdamage to repair completely and lead to fatigue fractures of trabeculae or whole bones. The modeling threshold normally lies comforably below the microdamage threshold. Since modeling normally adjusts bone architecture to keep strains from exceeding the modeling threshold, this keeps strains below the microdamage threshold, too, and voluntary activities do not cause more microdamage than remodeling can repair. Therefore, long-distance runners do not need more bone mass and strength than nonrunners of comparable age, sex, and body size.  相似文献   
29.
30.
Bedu-Addo  Frank K.  Tang  P.  Xu  Y.  Huang  Leaf 《Pharmaceutical research》1996,13(5):710-717
Purpose. The purpose of this study was to investigate polyethyleneglycol(PEG)-phosphatidylethanolamine(PE) conjugate interaction with phospholipid bilayers, in an attempt to explain the dependence of liposome circulation time on formulation. Methods. Differential scanning calorimetry, electron microscopy, dynamic light scattering and NMR were the major methods used in the study. Results. Mixtures of PEG-phospholipid conjugates and phosphatidylcholine existed in three different physical states: a lamellar phase with components exhibiting some miscibility, a lamellar phase with components phase separated, and mixed micelles. Beyond 7 mol% of PEG(l,000–3,000)-dipalmitoyl phosphatidylethanolamine (DPPE), and 11 mol% PEG(5,000)-DPPE in dipalmitoyl phosphatidylcholine (DPPC), a strong tendency towards mixed micelle formation was observed. All concentrations of PEG(12,000)-DPPE and PEG(5,000)-DPPE beyond 8 mol% formed phase separated lamellae with phosphatidylcholine. Decreasing the acyl chain length from C16:0 to C14:0 caused a decrease in tendency towards micelle formation and phase separation. These tendencies increased upon increasing acyl chain length to C18:0. Phase separation was at least partly due to PEG chain-chain interaction. This was supported by an increased fraction of PEG chains exhibiting a fast NMR transverse relaxation in DPPC/PEG(5,000)-DPPE mixtures as compared to that in distearoyl phosphatidylcholine (DSPC)/PEG(5,000)-dioleoyl-PE (DOPE). Conclusions. These phenomena are discussed in relation to both bilayer and steric stabilization of liposomes, and the lack of prolonged circulation with certain formulations is discussed.  相似文献   
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