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71.
Current guidelines recommend deferring liver transplantation (LT) in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection until clinical improvement occurs and two PCR tests collected at least 24 hours apart are negative. We report a case of an 18-year-old, previously healthy African-American woman diagnosed with COVID-19, who presents with acute liver failure (ALF) requiring urgent LT in the context of SARS-CoV-2 polymerase chain reaction (PCR) positivity. The patient was thought to have acute Wilsonian crisis on the basis of hemolytic anemia, alkaline phosphatase:bilirubin ratio <4, AST:ALT ratio >2.2, elevated serum copper, and low uric acid, although an unusual presentation of COVID-19 causing ALF could not be excluded. After meeting criteria for status 1a listing, the patient underwent successful LT, despite ongoing SARS-CoV-2 PCR positivity. Remdesivir was given immediately posttransplant, and mycophenolate mofetil was withheld initially and the SARS-CoV-2 PCR test eventually became negative. Three months following transplantation, the patient has made a near-complete recovery. This case highlights that COVID-19 with SARS-CoV-2 PCR positivity may not be an absolute contraindication for transplantation in ALF. Criteria for patient selection and timing of LT amid the COVID-19 pandemic need to be validated in future studies.  相似文献   
72.
This study was designed to examine ovarian performance, i.e.follicular growth, normal steroidogenesis and luteal phase function,following the administration of multiple increasing doses ofhuman follicle stimulating hormone (FSH) with a constant lowdose of luteinizing hormone (LH) in women with isolated hypogonadotrophichypogonadism. Human meno–pausal gonadotrophin (HMG) wasused in the first treatment cycle, starting with 150 IU of LHand 150 IU of FSH per day, for 7 days. The dose was increaseddaily with 75 IU of LH and 75 IU of FSH for another 7 days ifno response was detected by serial ultrasound measurements andserumoestradiol determinations. In the second treatment cycle,a constant dose of 75 IU of LH (using HMG) was administeredper day and up to 150 IU of FSH (using urofollitrophin) wassupplemented. If no response was detected after 7 days of treatment,the dose of FSH was increased. For the final stage of ovulationinduction, human chorionic gonadotrophin (HCG) was administeredin the presence of at least one follicle >17 mm in diameterbut with no more than three follicles >16mm in diameter.To verify the adequacy of the luteal phase, a pharmacokinetic/pharmacodynamicstudy of -HCG, oestradiol and progesterone was performed followingthe second treatment cycle only. Ovarian stimulation using aconstant dose of 75 IU of LH and increasing doses of FSH upto 225 IU, resulted in normal follicular growth and hormonalmilieu. Both women showed normal luteal phase oestradiol andprogesterone production and both women conceived following thesecond treatment cycle  相似文献   
73.
Summary A silver method is proposed for the selective, well-contrasted and reproducible demonstration of dark neurons in frozen, vibratome and paraffin sections cut at a thickness of 5 to 200 m from aldehyde-fixed brains. The Golgi-like staining of the dendrites enables asorting of dark neurons according to characteristic neuron classifications. The staining procedure includes an esterification with 1-propanol, a treatment with diluted acetic acid and development. The esterification strongly increases the argyrophilia of both dark neurons and mitochondria. Unwanted co-staining of mitochondria is suppressed by the acetic acid treatment, while a special developer is used to render the staining controllable. The applicability of the method to experimental neuropathology is demonstrated by Golgi-like staining of dark neurons in rat brains exposed, before transcardial perfusion-fixation and delayed autopsy, to various pathological conditions including ischemia, hypoglycemia, trauma, status epilepticus, deafferentation and poisoning with kainic acid, colchicine and sodium azide, respectively.  相似文献   
74.
阴沟肠杆菌Amp C酶的诱导性及对酶抑制剂的敏感性研究   总被引:6,自引:0,他引:6  
目的 探讨阴沟肠杆菌Amp C酶的特性及对酶抑制剂的敏感性,方法 用琼脂稀释法研究第四代头孢菌素头孢吡肟,第三代头孢菌素头孢他啶,头孢噻肟与β-内酰胺酶抑制剂舒巴坦联合对10株头孢他啶耐药菌的体外抗菌活性。应用紫外法和反转录多聚酶链反应(RT-PCR)研究临床常用β-内酰胺类抗生素对AmpC酶的诱导作用以及3种抑制剂对Amp C酶的抑制作用。结果 舒巴坦不能增强头孢他啶的抗菌作用,第四代头也菌素头孢吡肟对头孢他啶耐药菌有较好的抗菌活性。亚胺培南对Amp C酶的诱导作用较强,酶抑制剂R0481220具有较好的抑制作用,结论 产Amp C酶的阴沟肠杆菌引起的感染可考虑选用第四代头孢菌素头孢吡肟进行治疗。  相似文献   
75.
目的 比较 PGE2 阴道栓剂及催产素静滴引产的效果。方法 将 5 85例同样条件孕妇 ,随机分两组 ,分别给PGE2 阴道栓剂和催产素静脉滴注引产。结果 前列腺素组及催产素组引产成功率分别为 96 .3%和 79.92 % ;临产发动时间及总产程分别为 (2 .70± 0 .6 3) h,(3.0 1± 3.41) h和 (3.91± 0 .71) h,(6 .0 3± 3.5 0 ) h;剖宫产率分别为6 .8%和 18.18% (P<0 .0 1) ,有显著差异。结论  PGE2 栓剂用于足月妊娠引产效果显著、安全、方便 ,对促宫颈成熟意义重要 ,可缩短住院天数 ,减少住院费用。  相似文献   
76.
目的 :了解促排卵治疗对黄体中期子宫内膜雌激素受体 (estrogenreceptor,ER)、孕激素受体 (progesteronereceptor,PR)及其mRNA表达的影响。方法 :应用光学显微镜检测着床窗口子宫内膜、采用免疫组化及原位杂交方法检测正常及多囊卵巢综合征 (polycysticovariansyndrome ,PCOS)妇女促排卵治疗后子宫内膜黄体中期ER、PR及其mRNA的表达 ,放射免疫法测定同期血中雌激素 (estradiol,E2 )及孕激素 (progesterone,P)水平。 结果 :正常妇女黄体中期子宫内膜组织形态 2 2例中有 2 0例为分泌中期改变 ,2例为分泌早期改变。ER、PR弱表达 ,ERmR NA及PRmRNA的表达也较弱 ,而PCOS妇女治疗后黄体中期氯米芬 9/人绒毛膜促性腺激素组及氯米芬 /绝经期促性腺激素 /人绒毛膜促性腺激素组各 15例分别有 8/ 15及 7/ 15光镜下为分泌中期改变 ,其它为分泌早期改变。ER、PR的表达增强 ,其基因的表达也明显增强 ,血清P的水平相对较低。促性腺激素释放激素激动剂 /绝经期促性腺激素 /人绒毛膜促性腺激素组共 10例 ,E2 、P及P/E2 接近对照组 ,上述标志物的表达与对照组相似。但 3组PCOS分泌中期子宫内膜均有不同程度的间质增生、致密 ,腺体与间质发育不同步 ,且间质致密处ER、PR及其mR NA表达均下降。结论 :氯米芬 /人绒毛膜促性腺  相似文献   
77.
目的 :探讨一种晚期妊娠安全、简便、有效的引产方法。方法 :选择正常单胎头位足月妊娠具有引产指征而无禁忌证的妇女 12 7例 ,随机分为二组 ,米索组用米索前列醇 2 5 μg置于阴道后穹窿 ,催产素组用催产素 2 .5IU加入 5 %葡萄糖 5 0 0ml内静滴。对引产有效率分娩时间和剖宫产率进行了对比观察。结果 :引产有效率 :米索前列醇组明显高于催产素组。 (P <0 .0 5 )分娩时间米索前列醇组和催产素组有显著差异 (P <0 .0 5 )。剖宫产率两组有明显差异 (P <0 .0 5 )。结论 :米索前列醇用于晚期妊娠计划分娩安全、简便、有效。  相似文献   
78.
Objective To evaluate the possibility of preservation of the larynx after neoadjuvant chemotherapy by performing a conservative surgery instead of total laryngectomy initially planned, in patients with previously untreated laryngeal and piriform sinus squamous cell carcinoma (SCC). Study Design Retrospective study. Methods A total of 115 patients treated at Tenon Hospital with induction chemotherapy from 1985 to 1995, all with initial indication of radical surgery, were available for the study. The clinical tumor response was evaluated after three cycles of chemotherapy. According to this response, to preserve laryngeal functions, some patients had a modification of the treatment initially planned: radiation therapy essentially for complete responders, and conservative surgery for some partial responders. Results Of 69 patients with laryngeal cancer, 14 were treated by partial laryngectomy and 19 by radiation therapy; of 46 patients with piriform sinus cancer, 8 were treated by partial surgery and 12 by radiation therapy; the other patients were treated as was initially planned (total laryngectomy with partial pharyngectomy). Overall survival rates, estimated by the Kaplan‐Meier method, were not statistically different between the three treatment groups. The laryngeal functions were preserved in 54% of the patients who were alive at 3 years. Conclusion This report is a retrospective study, but these results suggest the possibility of using conservative surgery, instead of initially planned total laryngectomy, for good responders to induction chemotherapy with a small residual tumor.  相似文献   
79.
目的 研究评价牛骨形成蛋白 (b BMP) -白蛋白 -成纤维细胞生长因子 (b FGF)复合材料修复腭裂骨缺损的可行性。方法 建立家兔腭骨缺损模型 ,将固化的 b BMP-白蛋白 - b FGF复合材料植入骨缺损区 ,通过其骨诱导作用 ,诱导新骨生成 ,修复骨缺损。经 X线、组织学观察和钙含量测定。结果  b BMP-白蛋白 - b FGF有很强的骨诱导作用 ,可以诱导骨形成 ,实验组与对照组 X线骨修复分数评估分别为 12分 ,0分 ,组织学检查实验组骨修复完成 ,而对照组无骨修复 ,钙含量测定也有显著性差异。。结论  b BMP-白蛋白 - b FGF复合材料可诱导修复腭骨缺损 ,有良好的临床应用前景。  相似文献   
80.
In order to assess the efficacy and safety of recombinant humanfollicle stimulating hormone (FSH) in routine clinical use,ovarian stimulation with recombinant human FSH was performedin 71 patients prior to in-vitro fertilization (IVF) withoutgonadotrophin-releasing hormone (GnRH) analogues in a multicentre,non-comparative study. Human chorionic gonadotrophin (HCG) wasadministered to 58 patients (81.7%), 15 of whom underwent 19cycles with an initial dosage of three ampoules daily of recombinantFSH and 43 of whom underwent 152 cycles with four ampoules dailyfrom day 3 onwards. No significant differences were detectedbetween these two groups in all test parameters. The mean durationof treatment was 9.06 and 8.86 days respectively with a meannumber of 24.06 and 23.25 vials of recombinant human FSH administered.A mean number of 6.26 and 5.88 oocytes respectively was collected.The number of transferred embryos was 2.4 and 2.2. A clinicalpregnancy rate of 23.8% (10 out of 42) per transfer was achieved(30.9 and 20.6% respectively). Local tolerance of s.c. administrationwas excellent. Mild pain at the injection site was the dominantfinding in <20% of patients. Two cases of ovarian hyperstimulationsyndrome were noted. Recombinant human FSH is very attractiveto patients because it can be self-administered s.c. and thepreparation does not come from a human source. In conclusion,these data support the safety and efficacy of recombinant humanFSH in routine use for IVF.  相似文献   
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