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101.

Introduction and hypothesis

The rs1800255, COL3A1 2209 G>A polymorphism in the alpha 1 chain of collagen type III has been associated with an increased risk of pelvic organ prolapse (POP). In one of our previous studies however, polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) misdiagnosed rs1800255, COL3A1 2209 G>A in 6 % of cases. The high-resolution melting (HRM) analysis on the contrary obtained a 100 % accordance for this specific polymorphism and was used in the present study to validate this risk factor for POP.

Methods

In this case–control study, women with and without symptoms of POP were included and compared. DNA was extracted from blood samples. HRM analysis was used to assess for the presence of the homozygous rs1800255. Groups were compared using the Pearson chi-square, Mann–Whitney, and t tests. The discrepancy between HRM and PCR-RFLP results was investigated using PCR-RFLP results available from our previous study.

Results

The study included 354 women: 272 patients with POP and 82 controls; 18 (7 %) cases versus 3 (4 %) controls had a homozygous rs1800255, COL3A1 2209 G>A polymorphism (odds ratio 1.9, 95 % confidence interval 0.5–6.9, compared to the wild type), and thus no association between POP and the homozygous polymorphism could be demonstrated. A discrepancy between HRM and PCR-RFLP results was found in 8 % of the samples.

Conclusions

The previously found statistically significant association between the rs1800255, COL3A1 2209 G>A polymorphism as measured with PCR-RFLP and POP could no longer be demonstrated. This raises concerns regarding the results of other association studies using PCR-RFLP.  相似文献   
102.
Objective Successful resection of complex tumors involving the skull base (SB) depends on the ability to reconstruct the resulting defects. The objective of this study was to assess the outcomes of patients undergoing reconstruction after resection of SB tumors with free flaps.Methods From 1995 to 2010 a retrospective review of cases was undertaken. Demographics, histology, surgical management, complications, locoregional control, and survival were analyzed.Results We performed 62 flaps in 57 patients. There was a preponderance of sinonasal malignancies (45%), and most lesions involved the anterior SB (81%). A total of 94% of patients underwent radiotherapy. Reconstruction was undertaken mainly with anterolateral thigh (37%) or radial forearm (34%) flaps. Complications occurred in 17% of patients, and the flap''s success rate was 94%.Conclusion Free flaps are versatile and highly reliable for reconstructing defects resulting from resections of the SB. They should be considered for SB reconstruction of large three-dimensional defects as well as defects involving an irradiated field. Successful reconstruction of the SB can be performed using a small number of highly dependable flaps.  相似文献   
103.
BACKGROUND: Patients receiving chemotherapy for lung cancer usually modify their lung function during treatment with increases in forced expiratory volume in 1 second (FEV(1)) and forced vital capacity (FVC) and decreases in lung diffusion for carbon monoxide (DLCO). This prospective study was designed to evaluate functional changes in forced expiratory volume in 1 second, forced vital capacity, and DLCO after three courses of induction chemotherapy with cisplatinum and gemcitabine in stage IIIa lung cancer patients and to assess their impact on respiratory complications after lung resection. METHODS: From March 1998 to January 2001, 30 consecutive patients with N2 nonsmall cell lung cancer had surgical resection after neoadjuvant treatment. Pre-chemotherapy and postchemotherapy results of standard respiratory function tests and DLCO were compared in patients with and without postoperative respiratory complications. RESULTS: All 30 patients completed the chemotherapy protocol without respiratory complications. Significant improvements (p < 0.05) were recorded after chemotherapy in transition dyspnea score, PaO(2) (mean value from 79.8 to 86.4 mm Hg), forced expiratory volume in 1 second % (from 78.1% to 87.5%) and forced vital capacity % (from 88.1% to 103.3%). Lung diffusion for carbon monoxide was significantly impaired after chemotherapy (from 74.1% to 65.7%; p = 0.0006), as well as DLCO adjusted for alveolar volume (from 92.8% to 77.4%; p < 0.0001). One patient died after surgery and 4 patients (13.3%) experienced postoperative respiratory complications. Compared with patients without complications, these 4 patients had higher mean increase in FEV(1) after chemotherapy (+26.8% vs + 6.7%; p = 0.025), but greater mean decrease in DLCO/Va (-27.8% vs -13.6%; p = 0.03). Impact of change in DLCO on postoperative respiratory complications was not confirmed by multiple logistic regression analysis (p = 0.16). CONCLUSIONS: In lung cancer patients, forced expiratory volume in 1 second and forced vital capacity assessed after neoadjuvant chemotherapy are not reliable indicators of the likelihood of respiratory complications after surgery. The risk of respiratory complication may be directly linked to loss of DLCO/Va. Lung diffusion for carbon monoxide assessed after neoadjuvant chemotherapy is probably the most sensitive risk indicator of respiratory complications after surgery. We recommend that DLCO studies be performed before and after chemotherapy in lung cancer patients undergoing induction therapy.  相似文献   
104.
Robert L  Yelton J 《Military medicine》2002,167(12):990-993
Furuncular myiasis is a parasitic infestation of human and other vertebrate tissues by fly larvae of primarily two species: Dermatobia hominis (human botfly, t6rsalo, or berne) in Mexico and South and Central America and Cordylobia anthropophaga (tumbu fly or mango fly) in Africa. Cuterebra species (rabbit and rodent botflies) are also rarely reported to cause furuncular myiasis only within the United States. Although these species inhabit different geographic regions and have different life cycles, their clinical presentations can be similar. We describe a case of "imported" human botfly (D. hominis) furuncular myiasis in a U.S. Army soldier stationed in Germany. We review the life cycles of human botflies and key aspects of their clinical presentation, differential diagnosis, and various therapeutic modalities. Most physicians may never encounter myiasis and attribute a patient's complaints to an insect bite or skin infection that will heal without treatment. However, the diagnosis of furuncular myiasis should be considered by remembering the basic elements of this condition: recent travel history to the tropics and a sterile, persistent furuncle with sensations of movement and pain.  相似文献   
105.
Dopamine receptor stimulation causes vascular and neurohumoral responses that may be beneficial in patients with heart failure. Oral inactivity, emesis and adrenergic-induced arrhythmias have limited the use of currently available compounds. Fenoldopam (SKF-82526-J) is a new, orally available, selective, dopamine-receptor agonist with potent renal vasodilating properties (six times that of dopamine) without positive inotropic or adrenergic activity. Drug efficacy was clinically evaluated in 10 patients with heart failure after single oral doses of placebo and 50, 100 and 200 mg of medication. Placebo produced no changes. Peak efficacy was noted 30 minutes to 1 hour after the 200 mg dose with mean blood pressure decreasing from 96 +/- 15 (mean +/- SD) to 83 +/- 8 mm Hg (p less than 0.05), pulmonary capillary wedge pressure decreasing from 23 +/- 6 to 20 +/- 8 mm Hg (p less than 0.05) and mean pulmonary artery pressure decreasing from 32 +/- 9 to 29 +/- 8 mm Hg (p less than 0.05). Systemic vascular resistance decreased from 1,987 +/- 887 to 1,191 +/- 559 dynes.s.cm-5 (p less than 0.05) with a subsequent 55% increase in cardiac index from 2.2 +/- 1.1 to 3.1 +/- 1.3 liters/min per m2 (p less than 0.05). Heart rate and right atrial pressure did not change (p greater than 0.05). No emesis or new tachycardia was noted at any dose. Baseline hemodynamics generally returned within 3 to 4 hours. Fenoldopam, therefore, is a short-acting, orally effective drug that decreases systemic vascular resistance and increases cardiac index in patients with heart failure and represents a new class of oral compounds that may be useful in treating such patients.  相似文献   
106.
To evaluate the diagnostic usefulness of simultaneous determinations of 4 tumor markers (carcinoembryonic antigen, calcitonin, creatinine kinase-BB, and DNA), we studied 31 patients with lung cancer, 22 with benign lung disease, and 15 normal volunteers as control subjects. The measurements were made by radioimmunoassay in bronchoalveolar lavage (BAL) and in serum obtained on the same day. The results showed that in serum, only CEA levels were significantly higher in malignancy; in lavage fluids, all 4 markers were abnormally high in cancer patients when compared with control subjects (p less than 0.05); there was no correlation between the levels in lavage and those in the bloodstream. When the mean levels in lavage of the normal control subjects were designated as the limits for a positive test, significant association was found between malignancy and abnormally elevated marker concentration (p less than 0.01). The particular combination of CEA-BAL greater than 35 ng/mg, CEA-serum greater than 4 ng/ml, and calcitonin-BAL greater than 120 pg/mg taken together with the results of bronchoscopy (histologic and cytologic) showed the highest discriminating power between malignant and benign lung disease. The sensitivity of the bronchoscopy procedure increased from 50 to 89%, with at least 2 positive markers, and had a specificity of 71%. When both bronchoscopy and all 3 markers were negative, the results showed a negative predictive value of 100%. We conclude that tumor marker levels in lavage are a useful aid in the diagnosis of malignancy in patients undergoing bronchoscopy.  相似文献   
107.
Thirty-three patients with chest pain despite angiographically normal coronary arteries underwent both coronary flow studies during pacing and resting and exercise gated blood pool scintigraphy. During atrial pacing after administration of ergonovine, those patients developing their typical chest pain demonstrated significantly lower great cardiac vein flow (97 +/- 31 vs 150 +/- 33 ml/min, p less than .001), higher coronary resistance (1.27 +/- 0.43 vs 0.77 +/- 0.18 mm Hg/ml/min, p less than .005), and less lactate consumption (30.5 +/- 22.0 vs 69.7 +/- 41.1 mM . ml/min, p less than .005) and a higher left ventricular end-diastolic pressure after pacing (20 +/- 4 vs 12 +/- 1, p less than .001) compared with those without pain and in the absence of significant luminal narrowing of the epicardial coronary arteries. The 26 patients with abnormal vasodilator reserve demonstrated reduced left ventricular ejection fraction during exercise (58 +/- 8%) compared with the seven patients with appropriate vasodilator reserve (66 +/- 4%, p less than .05) and with a group of 52 control patients of similar age and sex distribution and free of known heart disease (66 +/- 10%, p less than .001). In addition, 12 of the 26 patients with abnormal vasodilator reserve demonstrated exercise-induced regional wall motion abnormalities. Many of these patients also manifested impaired left ventricular diastolic filling at rest compared with the control subjects (peak filling rate 2.6 +/- 0.7 vs 3.2 +/- 0.7 end-diastolic volume/sec, p less than .005). Thus, patients with chest pain resulting from abnormal vasodilator reserve demonstrate abnormalities of left ventricular systolic and diastolic function suggestive of myocardial ischemia.  相似文献   
108.
Chest pain and "normal" coronary arteries--role of small coronary arteries   总被引:5,自引:0,他引:5  
To study the mechanism of chest pain in patients with insignificant epicardial coronary artery disease, 50 patients underwent great cardiac vein (GCV) flow, oxygen content and lactate determinations at rest and during pacing, and left ventricular end-diastolic pressure (LVEDP) measurements at rest and after pacing. Twenty-four patients having typical chest discomfort during pacing demonstrated significantly lower increase in flow from baseline (36 +/- 18% versus 86 +/- 24%, p less than 0.001) and decrease in coronary resistance (-17 +/- 12% versus -43 +/- 7%, p less than 0.001) compared with 26 patients without pacing-induced chest pain, despite no significant difference in myocardial oxygen consumption (MVO2) between the 2 groups. Lactate consumption at a heart rate (HR) of 150 beats/min was significantly less (28.3 +/- 21.5 versus 51.3 +/- 35.8 mM X ml/min, p less than 0.001) and the increase in LVEDP from rest to after pacing was significantly greater (5 +/- 2 versus 1 +/- 2 mm Hg, p less than 0.001) in the chest pain group. After administration of ergonovine, 0.15 mg intravenously, to 46 of these patients, 31 had typical pain either at rest (1 patient) or during pacing. This group had significantly lower increase in flow (38 +/- 20% versus 107 +/- 38%, p less than 0.001), and decrease in coronary resistance (-16 +/- 12% versus -45 +/- 11%, p less than 0.001) compared with the 15 patients not having chest pain, despite no significant difference in MVO2 between the 2 groups. Patients with chest pain also had lower lactate consumption at a HR of 150 beats/min (39.2 +/- 23.6 versus 65.3 +/- 46.3 mM X ml/min, p less than 0.01), greater arterial-GCV oxygen difference (12.5 +/- 1.3 versus 11.6 +/- 1.0 ml O2/100 ml, p less than 0.05), and a more marked increase in LVEDP from rest to after pacing (11 +/- 3 versus 5 +/- 2 mm Hg, p less than 0.001). Quantitative coronary arteriography demonstrated no significant luminal narrowing of the epicardial coronary arteries in response to ergonovine. These data are consistent with the hypothesis that some patients with chest pain and angiographically normal epicardial coronary arteries have dynamic abnormalities of the small coronary arteries or coronary microcirculation that cause abnormal vasodilator reserve or vasoconstriction, resulting in myocardial ischemia and angina pectoris.  相似文献   
109.
We present two cases of recurrent progressive multifocal leukoencephalopathy (PML) in patients with long standing virally suppressed human immunodeficiency virus (HIV) and normal CD4+ T cell count who were taking stable regimens of highly active antiretroviral therapy (HAART). This has significant implications for other patients with a past history of PML, not just those with HIV but also those on medications such as natalizumab or fumarates.  相似文献   
110.
Grade progression and regression in recurrent urothelial cancer   总被引:3,自引:0,他引:3  
PURPOSE: Recurrent urothelial cancers are reported to have characteristics similar to those of the primary tumor, with 10% to 25% of low grade tumors recurring as high grade disease. We determined how often grade progression and regression occur and whether abnormalities in p53 protein expression in original tumors are preserved in recurrences. MATERIALS AND METHODS: Two groups of patients treated for recurrent stages Ta/T1 urothelial bladder cancers with at least 1 tumor-free examination between the index and recurrent tumors were reviewed. Group 1 included 115 patients in whom the first available tumor was compared with the last recurrence and group 2 included 42 in whom the initial tumor was compared with the first recurrence. Immunohistochemical analysis of p53 expression was performed on a subset of 34 tumor pairs. RESULTS: In group 1, 33 grade 3 tumors (45%) recurred as grade 1 or 2 tumors, while 9 of 82 grades 1 and 2 tumors (11%) recurred as grade 3 tumors. Five of 7 group 2 grade 3 tumors (71%) recurred as grade 1 or 2 disease, while 1 of 35 grades 1 and 2 tumors (3%) recurred as grade 3 disease. In the 34 pairs studied immunohistochemically 6 of 14 grade 3 tumors recurred at lower grades. Nuclear p53 over expression occurred in 21 index tumors (12 of 14 grade 3, 8 of 17 grade 2 and 1 of 3 grade 1) and in 9 recurrences (6 of 10 grade 3, 2 of 17 grade 2 and 1 of 7 grade 1). Only 7 of 21 p53 positive and 2 of 12 p53 negative index tumors were p53 positive on recurrence. CONCLUSIONS: While progression from low to high grade occurred in less than 15% of patients, grade regression was observed in almost 50%. The loss of p53 positivity in regressing tumors indicates that these recurrences are molecularly distinct from the corresponding initial tumor.  相似文献   
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