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61.
研究地西泮、苯巴比妥、普萘洛尔和西咪替丁对地西泮氧化代谢的影响及其药酶蛋白的初步分析,应用HPLC,SDS聚丙烯酰胺凝胶电泳和薄层扫描测定地西泮及其代谢物,并对大鼠肝微粒体和酶蛋白进行分离和含量测定。结果表明地西泮、普萘洛尔和西咪替丁使肝微粒体中P450含量明显降低。地西泮和普萘洛尔明显抑制地西泮C3羟化活性,大剂量普萘洛尔尚能抑制地西泮N脱甲基。苯巴比妥明显诱导P450生成,增强地西泮N脱甲基和C3羟化酶活性及分子量为51,000和59,000的电泳蛋白带,而地西泮、普萘洛尔则呈抑制作用。并发现,地西泮N脱甲基酶活性和分子量为59,000蛋白含量呈线性相关(P<0.05),而C3羟化酶活性则与51,000蛋白含量呈线性相关(P<0.01)。因此地西泮C3羟化代谢可能与51,000的P450酶蛋白有关,而N脱甲基代谢则可能与59,000的P450酶蛋白有关。  相似文献   
62.
Chlamydia trachomatis, the causative agent of trachoma, affecting hundreds of millions of people, is now recognized as a major cause of sexually transmitted disease. In many countries chlamydial infection now outstrips gonorrhoea as the major cause of genital tract infection. Chlamydial urethritis and cervicitis are frequently complicated by ascending infection involving the endometrium, the fallopian tubes and epididymis. This often results in serious reproductive sequelae, e.g., infertility in the female and ectopic pregnancy. Extra-genital manifestations of chlamydial infection may occur involving the eyes (follicular conjunctivitis), joints (arthritis), and distal intestinal tract. Infection of the newborn child during birth may result in ocular or lung disease.  相似文献   
63.
河南省传染性非典型肺炎患者胸部X线表现   总被引:1,自引:1,他引:0  
目的 :探讨传染性非典型肺炎的X线表现及变化规律。方法 :对河南省临床诊断的 1 5例患者发病后不同时间的系列胸片和CT进行回顾性分析。结果 :1 5例胸部X线病灶初始形态为斑片状 1 1例 (73.3% ) ,大片状 4例 (2 6 .7% ) ;双侧 9例 (6 0 .0 % ) ,单侧 6例 (4 0 .0 % ) ,均为中、下肺野 (1 0 0 % )。动态观察发现病变进展快 ,病变发展到高峰期时间为 4~ 1 4d , x±s(7.7± 3.2 )d ,双侧 1 3例 (86 .7% ) ,单侧 2例 (1 3.3% ) ,两肺叶及两肺叶以上病变者 1 4例 (93.3% )。病变开始吸收时间为 6~ 2 1d , x±s(1 1 .3± 4 .1 )d ;完全或基本吸收时间 8~ 2 6d , x±s(1 6 .4± 5 .0 )d。1 5例经治疗均痊愈出院。住院时间 1 8~ 4 2d , x±s(31 .9± 7.9)d。 结论 :传染性非典型肺炎的胸部X线特点为急性双侧或单侧多叶炎性浸润阴影 ,以中、下野常见 ,进展迅速 ,及时复查胸部X线对临床诊断及判断病情具有重要价值。  相似文献   
64.
Abstract. The objective of the present study was to compare the calcium set-points of E. M. Brown and A. M. Parfitt obtained by sequential citrate and calcium clamp in patients with primary hyperparathyroidism and healthy controls. Twenty-six patients with primary hyperparathyroidism were investigated and compared to 22 healthy volunteers. All participants were investigated by sequential calcium lowering and raising comprising the following four phases: Phase (1) blood ionized calcium lowering of about 0·20 mmol l-1; phase (2) steady-state (relative) hypocalcaemia of blood ionized calcium 0·20 mmol l-1 below baseline; phase (3) blood ionized calcium is raised to about 0·20 mmol l-1 above baseline; and phase (4) (relative) hypercalcaemia of blood ionized calcium 0·20 mmol l-1 above baseline. Serum parathyroid hormone (1–84) was measured by an immunoradiometric assay. Blood ionized calcium was measured by a calcium selective electrode. We found the calcium set-points of Parfitt to be 1·42 mmol l-1 (SD 0·12, n= 52) vs. 1·25 mmol l-1 (SD 0·04, n= 44) in patients and controls, respectively (P < 0·001). The calcium set-points of Brown were 1·32 mmol l-1 (SD 0·10, n= 26) vs. 1·13 mmol l-1 (SD 0·04, n= 22), respectively (P < 0·001). By comparing the calcium set-points of Parfitt and Brown, a strikingly good correlation was observed, in patients (r= 0·91, P < 0·001) and in controls (r= 0·85, P < 0·001). We demonstrate in this paper in vivo that Brown's and Parfitt's calcium set-points are raised in primary hyperparathyroidism and return to normal following parathyroidectomy. The values for Brown's and Parfitt's calcium set-points are significantly different, but strikingly well correlated, supporting the view that Brown and Parfitt describe two different points on the same sigmoidal curve, corresponding to 50% and about 85% inhibition of PTH maximum, respectively. The mathematical form of the sigmoidal curve between blood ionized calcium and parathyroid hormone is very similar in primary hyperparathyroidism and normal humans.  相似文献   
65.
全国哨点监测性病流行情况初步分析(1993-1996)   总被引:4,自引:0,他引:4  
目的  了解我国性病的现况、流行趋势和有关因素 ,作为制订性病防治规划的依据。方法  我国在 1 993~ 1 996年建立了性病哨点监测系统。该系统在原有性病发病较高的 1 6个城市监测点的基础上进行调整 ,在全国建立了 2 6个性病监测哨点。对哨点加强管理 (如督导和反馈 ) ,收集完整的监测资料 ,并进行专项调查。结果  4年内哨点监测系统共报告性病 2 0 2 86 6例 ,年平均发病率为 1 41 .46 / 1 0万 ,发病率逐年增长 ,但其速度较过去有所减慢。报告的病例男性多于女性 ,其性别比有逐年下降趋势。 2 0~ 39岁组患者占病例数的 82 .37% ,但儿童性病比过去明显增加。城市哨点发病率最高( 1 81 .86 / 1 0万 )。淋病仍为优势病种 ,但其发病呈逐年下降趋势 ;梅毒增加较快 (包括儿童梅毒 )。此系统已开始有 HIV/ AIDS病例的个别报告。在传染源中 ,暗娼占有相当高的比例。结论  哨点监测系统由于加强了管理 ,能较准确地描述当地的性病流行情况 ,特别是其流行趋势。  相似文献   
66.
About 4-10% of children and adolescents suffer from migraine. In the last few years, several studies have been performed to assess the efficacy and safety of triptans for the acute treatment of migraine in children and adolescents. Only sumatriptan nasal spray has been approved for the treatment of acute migraine with or without aura in adolescents aged 12-17 years in Europe. This review describes the results of the studies with sumatriptan nasal spray that have been performed in children and adolescents, including a study performed in the Netherlands.  相似文献   
67.
68.
1It has been suggested that lipophilic HMG CoA reductase inhibitors, like lovastatin and simvastatin, may cause sleep disturbance. 2Six hundred and twenty-one patients at increased risk of coronary heart disease were randomized in a single centre to receive 40 mg daily simvastatin, 20 mg daily simvastatin or matching placebo. To assess the effects of prolonged use of simvastatin on nocturnal sleep quality and duration, a sleep questionnaire was administered to 567 patients (95% of 595 survivors) at an average of 88 weeks (range: 44–129 weeks) after randomization. 3The main outcome measures were sleep-related problems and use of sleep-enhancing medications reported during routine study follow-up visits, and responses to the sleep questionnaire about changes in sleep duration and about various sleep events during the preceding month. 4No differences were observed between the treatment groups in the frequency of sleep-related problems reported, in the proportion of follow-up visits at which such problems were reported, or in the use of sleep-enhancing medications. The numbers who stopped study treatment were similar in the different treatment groups, and no patient stopped principally because of insomnia. In response to the sleep questionnaire, there were no significant differences between the treatment groups in reports of various sleep events during the preceding month, except that slightly fewer patients allocated simvastatin reported waking often. No differences in sleep duration were observed. 5This placebo-controlled trial does not indicate any adverse effects of prolonged treatment with simvastatin on systematically sought measures of sleep disturbance.  相似文献   
69.
Susceptibility to autologous and heterologous neutralization of primary human immunodeficiency virus (HIV)-1 isolates belonging to subtype B, to the B'-variant of subtype B or to subtype F from infected individuals residing in Rio de Janeiro was assayed. A lower infectivity of the B'- and F isolates when compared to the classical B-subtype HIV-1 isolates was observed. Comparisons of neutralization susceptibilities were carried out for 19 B-subtype, 11 B'-variant and two F-subtype HIV-1 isolates with plasma from autologous and heterologous samples. Frequency of autologous neutralization was slightly lower for B-subtype isolates in comparison to B'-variant isolates. Heterologous intra-subtype neutralization was significantly lower for B-subtype than for the B'-variant or the F-subtype isolates. While B-subtype isolates were neutralized by most anti-F-subtype plasma, F-subtype isolates, although most susceptible to F-subtype antibodies, were highly susceptible to neutralization by anti-B-subtype antibodies. Cross-neutralization for B'-variant and B-subtype isolates was not as extensive as observed for B- and F-subtype isolates. However, the results presented indicate a quite extensive cross-neutralization between Brazilian HIV-1 isolates.  相似文献   
70.
BACKGROUND.: There is agreement that a family history of hypertension (HT),is a predictor for the risk of diabetic nephropathy (DN) inpatients with type 2 diabetes, and possibly also type 1 diabetes.It follows that genes related to the risk of hypertension mustalso be considered candidate genes for DN. The 235T allele ofthe angiotensinogen gene was found to be related to primaryHT. METHODS.: To examine whether it is predictive for DN as well, we examinedthe angiotensinogen gene polymorphism in 230 healthy local controls,423 patients with type 1 diabetes (n=180 with DN; n=243 withoutDN) and 663 patients with type 2 diabetes (n=310 with DN; n=353without DN). The angiotensinogen gene M235T polymorphism wasdetermined using PCR amplification. RESULTS.: The following results were obtained (i) no significant differenceof genotype distribution (type 1: MM/MT/TT(%) 27.6/57.2/15.2vs. 27.2/56.1/16.7 (P=0.92); type 2: MM/MT/TT (%) 31.7/48.2/20.1vs. 32.9/46.8/20.3 (P=0.93)) or allele frequencies (type 1:M 0.56 vs. 0.55 (P=0.795); type 2: M 0.56 vs. 0.56 (P=0.86))was found, between diabetic patients with or without DN, (ii)no difference was found between normotensive and hypertensivediabetic patients. CONCLUSION.: The data argue against a role of the angiotensinogen gene M235Tpolymorphism in the manifestation of diabetic nephropathy orhypertension in diabetic patients.  相似文献   
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