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61.
目的    探讨大黄素-8-O-β-D-吡喃葡萄糖苷对牙龈卟啉单胞菌(P. gingivalis)唾液酸酶活性及其毒力基因表达的影响。方法    使用不同质量浓度的大黄素-8-O-β-D-吡喃葡萄糖苷(0.2、0.5、2、5、10 mg/mL)处理P. gingivalis W83(实验组),用未加药物的P. gingivalis W83作对照(对照组),采用荧光法检测大黄素-8-O-β-D-吡喃葡萄糖苷对P. gingivalis唾液酸酶活性的作用。5 mg/mL大黄素-8-O-β-D-吡喃葡萄糖苷作用于P. gingivalis W83,Real-time PCR法检测毒力基因fimA、fimR、fimS、kgp、rgpA和rgpB的表达情况。结果    大黄素-8-O-β-D-吡喃葡萄糖苷对P. gingivalis唾液酸酶活性产生了抑制作用,当其质量浓度为0.2、0.5、2、5、10 mg/mL时,对唾液酸酶活性的抑制率分别为11.4%、32.23%、40.21%、73.54%、84.31%。与对照组比较,实验组(5 mg/mL大黄素-8-O-β-D-吡喃葡萄糖苷处理)的fimA、fimR、fimS、kgp、rgpA和rgpB基因表达均下降,差异均有统计学意义(均P < 0.05)。结论    大黄素-8-O-β-D-吡喃葡萄糖苷可有效抑制P. gingivalis唾液酸酶活性,其抑制作用会降低细菌毒力基因表达,有望成为预防及治疗牙周炎的新型药物。  相似文献   
62.
目的 研究灌饲牙龈卟啉单胞菌(Porphyromonas gingivalis,P. gingivalis)对C57bl/6小鼠结肠炎症的诱导作用。方法 将P. gingivalis ATCC33277液体增菌后备用。将15只C57bl/6小鼠适应1周后随机均分为3组,高浓度组灌饲1 × 109 CFU P. gingivalis,低浓度组灌饲1 × 108 CFU P. gingivalis,而对照组则灌饲等量无菌BHI培养液。每只小鼠每天灌饲1次,3周后处死小鼠,采集结肠及脾脏组织,行HE染色观察组织学变化,并采用实时荧光定量PCR(qRT-PCR)检测结肠组织中CD3抗原(CD3 antigen,epsilon polypeptide,CD3)、受体型蛋白酪氨酸磷酸酶C(protein tyrosine phosphatase,receptor type C,B220)、黏附G蛋白偶联受体E1(adhesion G protein-coupled receptor E1,F4/80)、转化生长因子-β(transforming growth factor-β,TGF-β)及干扰素-γ(interferon-gamma,IFN-γ)的表达水平。结果 HE染色显示高浓度组小鼠结肠黏膜下结缔组织中淋巴滤泡增多,且高浓度组小鼠脾指数出现增高的趋势,但差异无统计学意义(P > 0.05)。qRT-PCR结果显示,与对照组及低浓度组相比,高浓度组小鼠的结肠组织中B220及TGF-β的表达水平显著增高(P < 0.05),其余指标表达水平差异无统计学意义(P > 0.05)。结论 P. gingivalis可诱导结肠炎症,从而增加牙周病患者对消化系统疾病的易感性,且其可能与牙周病病情的严重程度相关。  相似文献   
63.
64.
目的评价丙泊酚靶控输注在儿童鼻内镜手术中对血压、心率、术野出血及术后苏醒过程的影响。方法86例因腺样体肥大拟行手术患儿,ASA为Ⅰ-Ⅱ级,随机分成二组,每组43例,B组行丙泊酚靶控输注麻醉,I组行异氟醚吸入麻醉。分别观察手术开始后10,25,45 m in血压、心率变化及术野质量评分,记录术毕患儿自主呼吸恢复时间、睁眼时间、拔管时间,观察术后恶心、呕吐、躁动的发生率。结果①两组收缩压、舒张压和术野质量评分无显著差异;②B组患儿术后自主呼吸恢复时间、睁眼时间、拔管时间显著短于I组;③I组并发症高于B组。结论丙泊酚靶控输注用于儿童鼻内镜手术,血压、心率、术野质量评分佳,术毕麻醉恢复更为迅速、优良。  相似文献   
65.
Role of taurine accumulation in keratinocyte hydration   总被引:2,自引:0,他引:2  
Epidermal keratinocytes are exposed to a low water concentration at the stratum corneum-stratum granulosum interface. When epithelial tissues are osmotically perturbed, cellular protection and cell volume regulation is mediated by accumulation of organic osmolytes such as taurine. Previous studies reported the presence of taurine in the epidermis of several animal species. Therefore, we analyzed human skin for the presence of the taurine transporter (TAUT) and studied the accumulation of taurine as one potential mechanism protecting epidermal keratinocytes from dehydration. According to our results, TAUT is expressed as a 69 kDa protein in human epidermis but not in the dermis. For the epidermis a gradient was evident with maximal levels of TAUT in the outermost granular keratinocyte layer and lower levels in the stratum spinosum. No TAUT was found in the basal layer or in the stratum corneum. Keratinocyte accumulation of taurine was induced by experimental induction of skin dryness via application of silica gel to human skin. Cultured human keratinocytes accumulated taurine in a concentration- and osmolarity-dependent manner. TAUT mRNA levels were increased after exposure of human keratinocytes to hyperosmotic culture medium, indicating osmosensitive TAUT mRNA expression as part of the adaptation of keratinocytes to hyperosmotic stress. Keratinocyte uptake of taurine was inhibited by beta-alanine but not by other osmolytes such as betaine, inositol, or sorbitol. Accumulation of taurine protected cultured human keratinocytes from both osmotically induced and ultraviolet-induced apoptosis. Our data indicate that taurine is an important epidermal osmolyte required to maintain keratinocyte hydration in a dry environment.  相似文献   
66.
Surgical treatment for pulmonary hydatidosis (a review of 422 cases)   总被引:2,自引:0,他引:2  
OBJECTIVE: Hydatidosis in man is frequently encountered in sheep and cattle raising regions of the world. We reviewed 422 patients, treated surgically for pulmonary hydatid disease in our clinic between January 1980 and January 1998, assessing the clinical features and results of results of operative treatment management in our centre. PATIENTS AND METHODS: 52 of the patients were female and 370 were male. The median age of the patients was 33 years (range, 11 to 66 years). The cysts were located in the right lung in 214 (50.7%) patients, the left lung in 156 (37%) and bilaterally in 17 (4%) cases. We found an intrathoracic extrapulmonary cyst in 35 (8.3%) patients. We performed enucleation and capitonnage in 202 cases, wedge resection in 40, cystotomy and capitonnage in 171, and lobectomy in 9 patients. The high-risk patients were treated with Albendazol (10 mg/kg/day), for a period of 3 months postoperatively. RESULTS: Preoperative diagnosis was based primarily on chest roentgenograms and led to correct diagnosis in 347 cases (82.2%). An additional computerised tomography (CT) scan in 56 cases and magnetic resonavive imaging (MRI) were required in 15 cases. The diagnosis is established intraoperatively in 4 cases. Most (296) patients presented with a solitary lung cyst. The rest were found to have multiple cysts in one or more lobes. 87 of 422 also had cysts in the liver, 19 in the spleen, and 1 in the pancreas. The follow-up data was completed in 392 of 422 (92.8%) patients. The mean follow-up period was 4.3 years (2 to 19 years). We detected recurrence in 3 patients (0.71%). CONCLUSION: The effective treatment of hydatid cyst(s) in the lung is complete excision of the cyst(s) with maximum preservation of the lung parenchyma. Additional medical treatment with Albendazole should be carried out for high-risk group patients.  相似文献   
67.
Thal DR  Rüb U  Orantes M  Braak H 《Neurology》2002,58(12):1791-1800
BACKGROUND: The deposition of the amyloid beta protein (Abeta) is a histopathologic hallmark of AD. The regions of the medial temporal lobe (MTL) are hierarchically involved in Abeta-deposition. OBJECTIVE: To clarify whether there is a hierarchical involvement of the regions of the entire brain as well and whether there are differences in the expansion of Abeta-pathology between clinically proven AD cases and nondemented cases with AD-related pathology, the authors investigated 47 brains from demented and nondemented patients with AD-related pathology covering all phases of beta-amyloidosis in the MTL (AbetaMTL phases) and four control brains without any AD-related pathology. METHODS: Abeta deposits were detected by the use of the Campbell-Switzer silver technique and by immunohistochemistry in sections covering all brain regions and brainstem nuclei. It was analyzed how often distinct regions exhibited Abeta deposits. RESULTS: In the first of five phases in the evolution of beta-amyloidosis Abeta deposits are found exclusively in the neocortex. The second phase is characterized by the additional involvement of allocortical brain regions. In phase 3, diencephalic nuclei, the striatum, and the cholinergic nuclei of the basal forebrain exhibit Abeta deposits as well. Several brainstem nuclei become additionally involved in phase 4. Phase 5, finally, is characterized by cerebellar Abeta-deposition. The 17 clinically proven AD cases exhibit Abeta-phases 3, 4, or 5. The nine nondemented cases with AD-related Abeta pathology show Abeta-phases 1, 2, or 3. CONCLUSIONS: Abeta-deposition in the entire brain follows a distinct sequence in which the regions are hierarchically involved. Abeta-deposition, thereby, expands anterogradely into regions that receive neuronal projections from regions already exhibiting Abeta. There are also indications that clinically proven AD cases with full-blown beta-amyloidosis may be preceded in early stages by nondemented cases exhibiting AD-related Abeta pathology.  相似文献   
68.
Wiesner W  Schöb O  Hauser RS  Hauser M 《Radiology》2000,216(2):389-394
PURPOSE: To determine the role of radiographic assessment in patients who underwent an adjustable laparoscopic gastric banding (ALGB) for the treatment of morbid obesity, and to evaluate the frequency and type of postoperative complications. MATERIALS AND METHODS: From September 1995 to March 1998, 98 consecutive patients (18 men, 80 women; mean age, 39 years; age range, 22-62 years) with morbid obesity (mean body weight, 132 kg; mean body mass index, 47.1 kg/m(2)) underwent ALGB. In all patients, fluoroscopy was performed postoperatively to confirm band position and to exclude perforation and at 6-8 weeks later to measure and adjust the stoma between the pouch and stomach for optimal weight loss. All patients underwent another examination 12 months postoperatively, whereas patients with unsatisfactory weight loss or patients suspected of having complications were examined earlier and on several occasions. RESULTS: Port puncture was feasible in all cases, and stomal adjustments could easily be repeated. Absolute (ie, total) weight loss after 1 year ranged from 8.8% to 39.2% (mean, 18.3%). Twenty patients showed unsatisfactory weight loss. No early complications occurred. Late complications occurred in 34 patients and included pouch dilatation (concentric or eccentric with posterior slippage), eccentric band herniation, band penetration, disconnection, axial pouch herniation, and port-site infection. CONCLUSION: ALGB is an effective method in the treatment of morbid obesity. Radiographic assessments are crucial in the management of weight loss and detection of postoperative complications.  相似文献   
69.
The same questionnaire and study design was used in two surveys of asthma among all the children attending the 9-y compulsory school in Sundsvall in 1985 (n = 10 527) and 1995 (n = 9 165). A detailed questionnaire was distributed by post to the parents of all children who had answered in the affirmative to a simple screening question on asthmatic symptoms at the beginning of the autumn term. The questionnaire contained detailed questions on symptoms and asthma management. Our findings indicated a moderate increase in reported asthma-like symptoms and physician-diagnosed asthma between 1985 and 1995. The severity of symptoms was unchanged, despite a large community-based asthma campaign and a tenfold increase in the number of children receiving inhaled steroids. A validation analysis included an interview by a physician, a skin prick test, determination of specific IgE antibodies and spirometry. The oral interviews suggested that undertreatment was common. Many children had adequate medication at home, but this medication was not used properly. Finally, all 13-14-y-old children also replied to written and video questionnaires from the International Study of Asthma and Allergies in Childhood (ISAAC). It is likely that differences in study design explained the much higher prevalence of wheezing in this part of the study.  相似文献   
70.
Hepatic cysts are at the present time of widespread use of abdominal ultrasonography a frequent finding. The authors summarize contemporary diagnostic possibilities of liver cysts and submit variants of the therapeutic procedure in case of symptomatic liver cysts. They present their own experience with the treatment of hepatic cysts by the evaluation method combined with administration of 96% ethanol into the cyst. They compare this therapeutic procedure with the method of simple evaluation of the contents of the cyst. The method of evaluation of hepatic cysts under ultrasonographic control with subsequent administration of 96% alcohol appears to be more successful from the aspect of the long-term effect, manifested by the disappearance of clinical symptoms and non-refilling of the cyst.  相似文献   
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