全文获取类型
收费全文 | 23005篇 |
免费 | 1660篇 |
国内免费 | 402篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 790篇 |
妇产科学 | 509篇 |
基础医学 | 1346篇 |
口腔科学 | 14篇 |
临床医学 | 2358篇 |
内科学 | 1360篇 |
皮肤病学 | 69篇 |
神经病学 | 329篇 |
特种医学 | 402篇 |
外国民族医学 | 11篇 |
外科学 | 8963篇 |
综合类 | 3215篇 |
现状与发展 | 1篇 |
预防医学 | 1244篇 |
眼科学 | 9篇 |
药学 | 1681篇 |
14篇 | |
中国医学 | 496篇 |
肿瘤学 | 2250篇 |
出版年
2024年 | 67篇 |
2023年 | 288篇 |
2022年 | 610篇 |
2021年 | 780篇 |
2020年 | 730篇 |
2019年 | 741篇 |
2018年 | 724篇 |
2017年 | 754篇 |
2016年 | 683篇 |
2015年 | 833篇 |
2014年 | 1607篇 |
2013年 | 1515篇 |
2012年 | 1341篇 |
2011年 | 1626篇 |
2010年 | 1248篇 |
2009年 | 1240篇 |
2008年 | 1110篇 |
2007年 | 1133篇 |
2006年 | 1116篇 |
2005年 | 957篇 |
2004年 | 873篇 |
2003年 | 708篇 |
2002年 | 625篇 |
2001年 | 524篇 |
2000年 | 392篇 |
1999年 | 313篇 |
1998年 | 289篇 |
1997年 | 221篇 |
1996年 | 193篇 |
1995年 | 183篇 |
1994年 | 188篇 |
1993年 | 130篇 |
1992年 | 128篇 |
1991年 | 108篇 |
1990年 | 139篇 |
1989年 | 98篇 |
1988年 | 106篇 |
1987年 | 98篇 |
1986年 | 61篇 |
1985年 | 77篇 |
1984年 | 74篇 |
1983年 | 46篇 |
1982年 | 61篇 |
1981年 | 50篇 |
1980年 | 46篇 |
1979年 | 46篇 |
1978年 | 46篇 |
1977年 | 29篇 |
1976年 | 32篇 |
1973年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
2,6—二叔丁基对甲酚对大鼠尿生化指标的影响 总被引:2,自引:0,他引:2
以20,60和180mg/kg体重剂量给大鼠喂食2,6-二叔丁基对甲酚(BHT),检测尿中AST、ALP、LDH和GGT等指标变化。结果表明:随染毒时间延长,各尿酶含量逐渐出现显著性增高,病理学检查发现高剂量组有1例间质性肾炎,提示BHT对肾功能可能产生有害作用。 相似文献
92.
John P F A Heesakkers Vera Vandoninck Michael R van Balken Bart L H Bemelmans 《Neurourology and urodynamics》2003,22(3):243-245
AIMS: The rate of autologous urine production should not have a major disturbing influence on cystometric urodynamic parameters such as first filling sensation, normal desire to void, strong desire to void, and cystometric bladder capacity. Instructions to patients and drinking behavior can have considerable impact, especially if filling cystometry is preceded by free uroflowmetry. We studied the influence of autologous urine production during filling cystometry on total bladder volume. METHODS: Urodynamic investigations performed between September of 2000 and February of 2001 were analyzed. Only those urodynamic investigations for which total bladder capacity could be calculated were taken into account (i.e., catheterization before and after cystometry and no urine loss during the investigations). RESULTS: After screening, 186 investigations were used for further analysis. Mean filled volume (external infusion plus autologous urine production) was 346 +/- 152 mL, but mean real bladder capacity (i.e., voided volume + residual urine) was 391 +/- 170 mL. In all patients, 14% extra urine was produced due to autologous urine production (mean filling rate, 6.1 mL/min). In 42% of the investigations, the real bladder capacity was more than 110% of the infused volume. In 18% of the patients, the contribution of natural bladder filling was more than 25% of the infused volume. CONCLUSIONS: Natural bladder filling plays a substantial role during filling cystometry and has a disturbing influence on calculated urodynamic parameters. Attention should be paid to patient instructions before the urodynamic investigation. The combination of free uroflowmetry followed by filling cystometry should be avoided. This avoidance is especially important if interventional studies are performed. Careful interpretation of studies depending on bladder capacity parameters is mandatory, and such parameters should be corrected for autologous bladder filling. 相似文献
93.
原位M形回肠代膀胱术42例报告 总被引:10,自引:1,他引:9
目的 评价原位M形回肠代膀胱的疗效。 方法 男性膀胱恶性肿瘤患者 4 2例 ,腹膜外切除膀胱前列腺 ,截取 4 5~ 5 0cm回肠纵行剖开后M形折叠形成贮尿囊 ,输尿管插入贮尿囊内 1cm作吻合 ,贮尿囊底部与尿道 6针吻合 ,将贮尿囊完全置于腹膜外。 结果 本组 4 2例 ,术后随访12~ 96个月 ,平均 4 4个月。白天控尿良好者 38例 (90 .5 % ) ,夜间控尿良好者 36例 (85 .7% )。术后 12个月代膀胱容量 (36 1± 4 8)ml,最大排尿压 (86 .8± 2 1.4 )cmH2 O(1cmH2 O =0 .0 98kPa) ,最大尿流率(18.4± 6 .1)ml/s,无明显输尿管梗阻及返流。未发现尿道残端复发肿瘤。 结论 腹膜外切除膀胱可减少腹腔被肿瘤污染 ,避免肠管进入盆腔而影响手术操作。插入式输尿管吻合法 ,操作简单 ,术后形成小乳头有良好的抗返流作用 ,输尿管狭窄发生率低。代膀胱置于腹膜外 ,可减少肠粘连、肠梗阻、输尿管梗阻、腹腔内感染等并发症。改良后的原位回肠代膀胱术式 ,具有手术操作简单、术后并发症少、功能良好的特点 ,代膀胱在位置、形态、容量及输尿管抗返流等方面均接近正常膀胱。 相似文献
94.
输尿管回肠吻合术在可控性尿流改道中的应用 总被引:5,自引:0,他引:5
目的 评价输尿管回肠吻合术在可控性尿流改道术后抗返流及防止上尿路感染中的效果。方法 根治性膀胱切除术后行去带盲升结肠可控膀胱术和新膀胱术的患者10例,采用带回盲瓣的回肠段作为可控性膀胱的输入襻,双侧输尿管黏膜下隧道法与回肠吻合,随访观察患者术后输尿管返流及上尿路感染情况等。结果 10例手术顺利,术后随访6~36个月,均未发生输尿管返流或上尿路感染,1例发生单侧肾积水,为吻合口狭窄所致。结论 黏膜下隧道法输尿管回肠吻合术预防去带盲升结肠可控性尿流改道术后输尿管返流及上尿路感染效果良好。 相似文献
95.
本文报道用550型全自动生化分析仪,以速率法测定尿NAG活性及本室尿NAG活性的正常参考范围;并对可能影响尿NAG活性的尿PH,尿素浓度等进行了干扰试验及分析。 相似文献
96.
97.
Shinichiro Kitada Kumiko Kato Alan J. Wein Robert M. Levin 《Neurourology and urodynamics》1989,8(3):255-262
We were able to produce two highly reproducible experimental models (in the rabbit) that demonstrated a high degree of reflex bladder contractile activity. In one model, a somatovesical reflex was induced by touching or pinching the perineal area. This reflex may be organized through a neurogenic reflex at the spinal level. In another model, rhythmic bladder contractions were produced by distal urethral constriction in the absence of bladder distension. These rhythmic contractions were thought to be due to a supraspinal reflex. In both types of contractile reflexes, intravenous administration of hexamethonium inhibited the reflex contractile activity virtually completely, intravenous atropine inhibited over 90% of the induced contractile activity, thus suggesting that these contractions were mediated reflexly through cholinergic stimulation. These two models of reflex bladder contractions should be useful for the study of hyperreflexic bladders. 相似文献
98.
对经手术和病理证实的83例膀胱肿瘤进行超声显像和膀胱镜检查的对比性分析。结果表明,膀胱镜对膀胱肿瘤的诊断符合率为97.5%,略高于超声显像符合率的95.2%;但对膀胱肿瘤的术前分期,膀胱镜检查尚存在局限性,而超声显像可弥补膀胱镜检查的不足。本文超声显像对膀胱肿瘤的术前分期准确率达89.5%。超声显像对小于0.5cm的小膀胱肿瘤之检出率不如膀胱镜高。因此在常规检查以及对肿瘤的术前分期时,应以超声显像作为首选,同时结合膀胱镜检查,可进一步提高膀胱肿瘤的术前诊断正确率。 相似文献
99.
U. Walter D. Dressler A. Wolters M. Wittstock R. Benecke 《European journal of neurology》2006,13(12):1291-1297
Urinary dysfunction is very common in idiopathic Parkinson's disease (PD) and manifests primarily with symptoms of overactive bladder (OAB). Affection of central serotonergic systems has been suggested to play a role in OAB. The objective of this study was to evaluate whether in PD patients with OAB symptoms a specific alteration of the brainstem raphe (BR), which contains serotonergic neurons, can be detected with transcranial sonography (TCS). Of 116 PD patients enrolled, 19 had PD-related OAB symptoms (OAB+) unlike remaining 97 patients (OAB−). Patients were examined by a sonographer blinded to the clinical data. Reduced echogenicity of BR was found in 12 (63%) OAB+ patients but only in 18 (19%) of 93 assessable OAB− patients (Mann–Whitney U -test, P < 0.001). In OAB+ patients, lower raphe echogenicity score was associated with longer duration of OAB symptoms ( anova , P = 0.033). Other TCS findings such as echogenicity of substantia nigra, thalami, lenticular and caudate nuclei, and widths of third and lateral ventricles did not differ between OAB+ and OAB− patients. TCS findings suggest a pathogenetic role of BR in OAB related to PD. Alterations may reflect disturbance of its central serotonergic system. 相似文献
100.
尿路感染是临床常见病和多发病,同时也是最常见的医院获得性感染.尿路感染的临床表现多样,症状不典型,白细胞尿和菌尿的检出是其筛检和确诊的重要指标.本文结合尿路感染的发病机制、诊断标准,对尿中白细胞和细菌检验项目和技术的临床意义及应用评价做了简要概述. 相似文献