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51.
带蒂腹直肌包绕阴茎增强犬尿道压力的研究   总被引:1,自引:0,他引:1  
目的探讨采用带蒂腹直肌包绕球部尿道治疗男性尿失禁的可行性。方法成年雄性比格犬10条,游离阴茎周围组织,建立类似尿失禁模型。取长8.0cm,宽2.5cm全层带蒂的腹直肌。包绕球部尿道处阴茎1周。术前,术中,术后1个月、2个月分别测定尿道压力变化。结果术前平均最大尿道压力为(48.9±11.0)cm H_2O,使用带蒂腹直肌包绕阴茎后,平均最大尿道压力为(78.3±20.5)cmH_2O,与术前相比,差异有统计学意义(t=4.995,P<0.01)。术后1个月和术后2个月复查时,平均最大尿道最大压力分别为(92.2±31.6)cm H_2O和(88.3±22.4)cm H_2O,与术前相比差异均有统计学意义(t=4.011,P<0.01和t=6.058,P<0.01)。结论采用带蒂腹直肌包绕球部尿道能明显提高尿道压力,为采用此法治疗男性尿失禁提供了实验依据。  相似文献   
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尿道压监测下球部尿道悬吊术治疗男性获得性尿失禁   总被引:4,自引:2,他引:4  
目的探讨尿道压监测下球部尿道悬吊术治疗男性获得性尿失禁的疗效。方法2000年lO月至2004年9月收治男性获得性尿失禁25例,年龄18~81岁,平均66岁。其中后尿道狭窄行尿道成形术后6例,根治前列腺切除术后4例,良性前列腺增生(BPH)行经尿道前列腺电切术(TURP)后6例,BPH行前列腺摘除术后9例。尿失禁病程1~12年,平均4年。完全性尿失禁8例,压力性尿失禁17例,需尿垫1~5块/d,平均3块/d。术前均经盆底肌锻炼无效。尿动力学检查平均最大尿道压52cm H2O(1cm H2O=0.098kPa)。平均功能性尿道长度1.4cm。均在尿道压监测下行球部尿道悬吊术。结果手术结束时平均尿道压96cm H2O,平均功能性尿道长度3.5cm。术后完全控尿21例,尿失禁改善3例,排尿困难1例,经膀胱颈部电切后排尿通畅。术后1个月B超检查剩余尿均〈20ml;23例平均最大尿流率15ml/s。随访1年以上22例,1例于术后2年死于脑溢血,2例于术后1年和2年压力性尿失禁复发,其余19例排尿和控尿良好。结论尿道压监测下球部尿道悬吊术是治疗男性尿失禁的有效方法。  相似文献   
54.
Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph.  相似文献   
55.
Inactivation of deoxyribonucleic acid (DNA) mismatch repair genes, most commonly human mutL homologue 1 (hMLH1) or human mutS homologue 2 (hMSH2), is a recently described alternate pathway in cancer development and progression. The resulting genetic instability is characterized by widespread somatic mutations in tumor DNA, and is termed high-frequency microsatellite instability (MSI-H). Although described in a variety of tumors, mismatch repair deficiency has been studied predominantly in colorectal carcinoma. Most MSI-H colorectal carcinomas are sporadic, but some occur in patients with hereditary nonpolyposis colorectal cancer (HNPCC), and are associated with germline mutations in mismatch repair genes. Until now, the identification of MSI-H cancers has required molecular testing. To evaluate the role of immunohistochemistry as a new screening tool for mismatch repair-deficient neoplasms, the authors studied the expression of hMLH1 and hMSH2, using commercially available monoclonal antibodies, in 72 formalin-fixed, paraffin-embedded tumors that had been tested previously for microsatellite instability. They compared immunohistochemical patterns of 38 MSI-H neoplasms, including 16 cases from HNPCC patients with known germline mutations in hMLH1 or hMSH2, with 34 neoplasms that did not show microsatellite instability. Thirty-seven of 38 MSI-H neoplasms were predicted to have a mismatch repair gene defect, as demonstrated by the absence of hMLH1 and/or hMSH2 expression. This included correspondence with all 16 cases with germline mutations. All 34 microsatellite-stable cancers had intact staining with both antibodies. These findings clearly demonstrate that immunohistochemistry can discriminate accurately between MSI-H and microsatellite-stable tumors, providing a practical new technique with important clinical and research applications.  相似文献   
56.
目的通过构建以MDR1启动子为启动序列的双荧光素酶报告基因系统并进行活性分析,为MDR1基因表达的单靶点调控研究和逆转剂的筛选提供一种有效的方法。方法从HCT-8细胞中提取DNA并克隆含有MDR1基因启动子中Y—box序列。将该序列重组到萤光素酶报告基因载体pGL-3.Basic的启动区域中,从而构建报告基因载体pGL-MDR1。将pGL-MDR1和pRL-TK载体共转染到HCT-8和HCT-8/VCR细胞中。通过调节不同载体的比例来优化转染效率。利用MDRI基因激活剂(热诱导)和抑制剂(EGCG)等处理来分析其启动转录活性受外界因素的影响。结果通过直接测序法验证了pGL-MDR1含有MDR1基因启动子Y—box序列且没有出现碱基突变。在pGL-MDR1和pRL-TK的转染比例为5:5时,转染效率最高并具有最高的萤光素酶活性。通过MDR1基因激活处理后表现为时间依赖性地激活MDR1基因的表达,而MDR1基因抑制剂的作用则相反。结论MDR1启动子为启动序列的双荧光素酶报告基因系统建立成功。该系统不但可以用于研究活体生物发光成像和MDRI基因表达的机理,而且可用于单靶点的多药耐药抑制剂的筛选。  相似文献   
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Background: Electrical stimulation (ES) of the stomach has been shown to modulate LESP. Electrical stimulation, using neural high frequency stimulation (NGES) can induce contractions of the smooth muscle of the gut. The purpose of this study was to determine if electrical stimulation of the LES can affect LESP. Methods: Four female hound dogs, weight: 20–25 kg, underwent an esophagostomy that allowed the introduction of a sleeve manometry catheter into the esophagus. They were also implanted with a pair of electrodes along the longitudinal axis of the LES. After 3 weeks of recovery, they underwent esophageal manometry recording during control and ES, performed randomly on separate days, using 4 different stimulations: 1‐Low frequency: freq: 6 cycles/min, pulse: 350 milisec, amp: 5 mAmp; 2 High‐frequency: freq: 50 Hz, pulse: 1 milisec, amp: 5 mAmp; 3‐ NGES: freq: 50 Hz, pulse:20 milisec, amp:10 volts; 4‐ High‐frequency, circular: freq: 20 Hz, pulse:1 milisec, amp:5 mAmp. All recordings were performed 1 hour after consumption of 3 ounces of canned dog food, to prevent fluctuations in LESP and under mild sedation (acepromazine 0.5 mg kg­1). Tests consisted, during ES days, of 3 periods of 20 minutes each: control , stimulation and post stimulation. The effect of NGES was also tested under anesthesia and following administration of L‐NAME 50 mg kg­1 IV. and also atropine 0.05 mg kg­1 IV. Analysis: area under the curve (AUC) and pressure were compared among the 3 periods. Data shown as mean ± SD, ANOVA and t‐test, p < 0.05. Results: Sustained increase in LESP was observed during low frequency stimulation, 32.1 ± 12.8 vs. 42.4 ± 18.0 vs. 50.1 ± 23.6, control vs. stimulation vs. post stimulation respectively, p = 0.013. AUC also significantly increased during and after stimulation, 39,320.3 ± 15,722 vs. 51,294 ± 21,826 vs. 59,823.6 ± 28,198.4 mmHgxsec, control vs. stimulation vs. post stimulation respectively, p = 0.01. There was no significant change with other types of ES. NGES induced an initial rise in LESP followed within few seconds by relaxation with slow resumption of pressure over a 1 minute period. L‐NAME increased LESP and augmented the initial rise in LESP following NGES but markedly diminished or abolished the relaxation phase. Atropine lowered LESP and abolished the initial rise in LESP induced by NGES. Conclusions: Low frequency ES of the LES increases LESP in conscious dogs. NGES has dual effect on LESP: an initial stimulation, cholinergically mediated, followed by relaxation mediated by nitric oxide.  相似文献   
59.
Background  Palmoplantar pustulosis (PPP) discloses some differences compared to vulgar psoriasis (PV) in terms of age of onset, female predominance and low occurrence of psoriasis lesions elsewhere. Cigarette smoking has been associated to PPP in international studies; nevertheless, these studies were never performed among Brazilian.
Objectives  To compare prevalence of smoking among PPP, PV and other dermatologic patients (NPD).
Methods  Case–control study involving 25 PPP patients from a reference psoriasis centre. Two control groups were matched according to gender and age: 50 patients with PV and 50 NPD. Confounders were adjusted by conditional multiple logistic regression.
Results  Among cases, 84.0% were female and PPP age of disease onset (41.4 years) was greater than PV (34.5 years). Prevalence of ever smoking was higher among cases (92.0%) than PV (52.0%) and NPD (30.0%). Adjusted odds ratio of PPP ever smoking compared to PV and NPD was 9.5 and 36.2, respectively. All smokers reported the onset of their habit before the development of PPP.
Conclusions  There was significant association between PPP and smoking. However, the impact of giving it up in the clinical course of the disease remains to be established.  相似文献   
60.
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