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1.
顶空气相色谱法测定医用透明质酸钠凝胶中乙醇残留量   总被引:1,自引:0,他引:1  
用顶空气相色谱法,测定医用透明质酸钠凝胶中乙醇残留量.采用HP-5毛细管柱;柱温:100℃;进样口温度:200℃;检测器温度:250℃;气体流速:N210ml/min,H240ml/min,Air375ml/min.结果表明:线性试验与精密度良好,回收率为96%~105%,RSD为5.6%,检出限为0.1μg/g.采用顶空气相色谱法,测定医用透明质酸钠凝胶中乙醇残留量,简便、准确.  相似文献   
2.
Rats, initiated to self-administer 10% (v/v) ethanol in an operant situation using the sucrose-fading procedure, received bilateral n. accumbens microinjections of d-amphetamine prior to operant sessions. Doses of 4 micrograms, 10 micrograms and 20 micrograms/brain were administered and some animals also received a 4 microgram/brain dose of LY171555. Three different effects were observed: increased, decreased and no change in total session responding. There was no clear relation between injection area in the n. accumbens and type of effect observed. For either an increase or decrease in total session responding, momentary response rates were decreased. Both d-amphetamine and LY171555 produced similar results. The data support the hypothesis that dopamine in the n. accumbens is involved with ethanol reinforced operant responding but in a complex manner.  相似文献   
3.
本文介绍了对山芋干酒精废糟进行粗滤,所得滤液全部回用于酒精生产的实验室研究结果。其方案之一是将粗滤液先培养丝状茵,再将二次过滤液回用;方案二是将粗滤液直接回流。经过十三到十五次的全回流表明,粗滤液全回流是可行的。另外,每100ml酒糟粗滤时可得到含干物质15%左右的湿滤渣约33g,其粗蛋白含量为17.5%(干基)。将粗滤液摇瓶培养根霉26号茵株10小时可得粗干茵体1.5—2.0g/100ml,其粗蛋白含量25%左右。  相似文献   
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目的探讨胃饲乙醇预处理对肝脏缺血再灌流损伤的影响,并初步评价其预处理的可行性。方法40%乙醇胃饲Wistar大鼠。分组:①大鼠36只,随机分6组:A组8g/kg、B组7g/kg、C组6g/kg、D组5g/kg、E组4g/kg、正常组0g/kg;以中毒症状及肝组织病理为指标,判定大鼠乙醇急性中毒剂量。②大鼠78只,随机分为4组:正常对照组(N)、单纯乙醇组(E)、单纯缺血组(ISCH)、胃饲乙醇预处理组(EPC);采用尾叶转流下的肝缺血模型,于再灌流3、6、12、24h留取标本。结果急性胃饲乙醇≤5g/kg预处理后,动物中毒症状轻,无死亡;乙醇预处理可以在一定程度上减轻肝脏90min的缺血再灌流损伤。结论适当剂量的乙醇胃饲预处理是一种安全的预处理措施,有望成为增强肝脏对缺血再灌流损伤耐受性的一种较好的预处理方式。  相似文献   
6.
Objectives: Given that clinical and laboratory studies suggest that ethanol and hemorrhagic shock (HS) potentiate traumatic brain injury (TBI), the authors studied the effects of ethanol in a model of combined TBI and HS.
Methods: A controlled porcine model of combined TBI and HS was evaluated for the effect of ethanol on survival time, hemodynamic function, and cerebral tissue perfusion. Anesthetized swine (17–24 kg) were instrumented, splenectomized, and subjected to fluid percussion TBI with concurrent 25-mL/kg graded hemorrhage over 30 minutes. Two groups were studied: control ( n = 11) and ethanol ( n = 11). Ethanol, 3.5 g/kg intragastric, was given 100 minutes prior to TBI/HS. Systemic and cerebral physiologic and metabolic parameters were monitored for 2 hours without resuscitation. Regional cerebral blood flow (rCBF) and renal blood flow were measured with dye-labeled microspheres. Data were analyzed with 2-sample t-test and repeated-measures ANOVA.
Results: Ethanol levels at the time of injury were 162 ± 68 mg/dL. Average TBI was 2.65 ± 0.35 atm. Survival time was significantly shorter in the ethanol group (60 ± 27 min vs 94 ± 28 min, p = 0.011). The ethanol group had significantly lower mean arterial pressure, cerebral perfusion pressure, and cerebral venous
O2 saturation in the postinjury period. Cerebral O2 extraction ratios and cerebral venous lactate levels were significantly higher in the ethanol group. A trend toward lower postinjury rCBF in all brain regions was observed in the ethanol group.
Conclusion: In this TBI/HS model, ethanol administration decreased survival time, impaired the hemodynamic response, and worsened measures of cerebral tissue perfusion.  相似文献   
7.
Symptomatic liver cyst: Special reference to surgical management   总被引:2,自引:0,他引:2  
We conducted a retrospective study of 14 patients with symptomatic liver cysts to evaluate current therapeutic interventions for this condition. Abdominal pain (n = 7) or abdominal mass (n = 5) were the most frequent presentations. Three patients also had renal cyst. Percutaneous aspiration with ethanol sclerotheraphy was carried out in 4 patients and all cysts so treated diminished in size, with relief of the symptoms. One patient was treated by aspiration only and re-retension occurred. Cystectomy was performed in 2 patients, unroofing in 5, and fenestration in 2 patients. All patients gained relief of symptoms, with no recurrence of symptoms. Computed tomography revealed that the cysts were diminished or were no longer observable after all the treatments. Our experience indicates that unroofing, fenestration, and cystectomy are safe and suitable procedures for treatment of the condition. Ethanol sclerotherapy may be a feasible alternative to surgical intervention in selected patients. Received for publication on July 23, 1997; accepted on Dec. 25, 1997  相似文献   
8.
A series of experiments evaluated the determinants of preference for mixtures of ethanol plus sucrose relative to sucrose in rats. One dipper served 10% ethanol mixed with 10% sucrose, and the second dipper served 10% sucrose. Lever presses operated each dipper according to a variable-interval 5-s schedule. In three experiments the subjects were given pre-session meals of sucrose (2.5–20 ml) or sucrose (20 ml) plus chow (5 or 10 g). Pre-session meals decreased responding maintained by sucrose but not responding maintained by ethanol mixture. In two experiments body weight was varied from 85% to 125% of the initial free-feeding values. Increases in body weight, like pre-session meals, decreased responding reinforced by sucrose, but typically did not decrease responding reinforced by ethanol mixture. Throughout most of the study, ethanol consumption remained at about 1.25 ml per half hour session (3–4 g/kg per 30 min). For example, pre-session access to ethanol mixture decreased within-session ethanol consumption, but total consumption, counting both sources, remained about 1.25 ml/session. The within-session patterns of responding also differed. Responding reinforced by ethanol mix decreased as a function of ethanol consumption, whereas responding reinforced by sucrose was relatively constant throughout the session. The simplest explanation of the results is that ethanol's pharmacological consequences regulated preference.  相似文献   
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目的 观察啤酒及乙醇对不同剂量γ射线照射小鼠所诱发的骨髓细胞染色体畸变的影响.方法 雄性健康BALB/c小鼠,随机分成对照组、啤酒组和乙醇稀释液组,分别用1 ml灭菌生理盐水、啤酒及乙醇稀释液灌胃.30 min后给予不同剂量γ射线1次全身照射.照射后24 h颈椎离断法处死动物(处死前4 h按4 μg/g体重腹腔注射秋水仙胺),立即取双侧股骨,进行骨髓细胞常规染色体制片、染色.每一剂量点选取5个个体进行染色体畸变观察.每只动物镜检分析100个细胞分裂相.结果 啤酒组及乙醇稀释液组染色体畸变率在照射剂量达0.5 Gy以上时明显降低(P<0.05或P<0.01),其中啤酒组的下降比乙醇稀释液组更明显.结论 啤酒中除乙醇以外的其他成份(如酚类化合物等)也发挥了降低染色体畸变的作用.  相似文献   
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