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81.
82.
PURPOSE: To compare the results of traditional laser photoablation and wavefront-supported customized ablation (WASCA) in hyperopic photorefractive keratectomy (H-PRK). METHODS: This was a prospective study, comparing two treatment groups, each comprising 40 eyes of 20 patients. Wavefront aberrations were examined using a Shack-Hartmann aberrometer. Preoperative refraction was similar in the two groups; in the traditional H-PRK group (Group 1) it was +3.10 +/- 0.85 D, and in the WASCA-guided group (Group 2) it was +2.90 +/- 0.80 D. H-PRK was performed with the Asclepion-Meditec MEL 70 flying-spot excimer laser. The follow-up time was 6 months. RESULTS: In Group 1, mean postoperative refraction was +0.14 +/- 0.24 D, and in Group 2, -0.10 +/- 0.25 D; mean uncorrected visual acuity was 0.92 +/- 0.16 in Group 1 and 0.95 +/- 0.18 in Group 2. Mean best spectacle-corrected visual acuity was 0.96 +/- 0.04 in Group 1 and 1.06 +/- 0.13 in Group 2. In Group 1, 67.5% (27 of 40 eyes), and in Group 2, 85% (34 of 40 eyes) were within +/-0.50 D of target refraction. Regarding change of spectacle-corrected visual acuity in Group 1, 5% (2 of 40 eyes), and in Group 2, 20% (8 of 40 eyes) gained one Snellen line compared to the preoperative; in Group 1, 10% (4 of 40 eyes), and in Group 2, 12.5% (5 of 40 eyes) lost two Snellen lines. In Group 2, the root mean square value for the higher order aberration increased from the initial 0.134 to 0.257 microm at 6 months after surgery. CONCLUSIONS: WASCA-guided hyperopic-PRK treatment was found to be safe and predictable. The results were better than those achieved with traditional PRK performed using the same flying-spot type excimer laser.  相似文献   
83.
Introduction: Platelet glycoprotein IIb/IIIa is a membrane receptor with a central function in the platelet adhesion and ultimately in the thrombus formation. Two major variants of the gene encoding the IIIa subunit, called PLA1 (A1) and PLA2 (A2), have been identified in the general population. There are indications that the A2 allele can also be associated with acute thrombosis or stroke. The purpose of this study was to study the distribution of the A2 allele in different vascular subtypes of stroke disease. Materials and methods: A total of 638 consecutive patients were analyzed and classified as having large vessel pathology (n=168) or a small vessel infarct (n=210). Localization of the vascular occlusions was deducted from analysis of the magnetic resonance imaging (MRI) scan results in stroke patients. The remainder patients were listed into a mixed vascular pathology group (n=167). Patients with other or poorly characterized stroke etiology were excluded from the study (n=93). Results: In the small vessel and mixed vascular pathology groups, the PLA2 allele frequency was similar to that in the controls. By contrast, PLA2 allele frequency was approximately two-fold higher in patients with large vessel pathology (23.3%) than in the stroke-free control subjects (11.7%, p<0.0005). Multivariate logistic regression analysis of data confirmed this association with an odds ratio (OR) of 2.9 (95% confidence interval [CI]: 1.6–4.9, p<0.0005). Conclusions: These data suggest that the PLA2 allele is more frequent in brain infarcts associated with large-vessel occlusion.  相似文献   
84.
Surgical treatment for locally advanced cancer of the pancreas head with vascular invasion is controversial. It is regarded as a contraindication for resection by most surgeons, others perform resection involving the vessel. We performed pancreaticoduodenectomy with vascular resection in a 61 year old patient. The vascular reconstruction was performed using reversed saphenous vein. We review and analyse clinical, and operative data and results.  相似文献   
85.
The surgical treatment of ventral hernias has changed in the last decade. Conventional methods involve tightening of the abdominal fascias is the reason for high recurrence rate. While the use of mesh reduces the recurrence rate, it does not change the rate of other complications, in particular, the risk of infection. We report the results of laparoscopic repair of ventral hernias performed in 15 patients (10 female, 5 male). The average age of patients was 59.5 years (39-79). Indications included 7 recurrent incisional hernias (3 patients had second recurrence, 4 patients had first recurrence operated on without mesh in the first operation); 5 patients with primary incisional hernias; and 3 primary umbilical hernias. The mean size of the defect was 66.2 cm2 (16-130 cm2). Average operation time was 101 minutes (64-190 min). In the postoperative period 1 patient developed seroma, and 4 patients developed ileus each was successfully treated conservatively. In one patient a second-look laparoscopy was performed because of neuralgia. Length of hospital stay varied between 3 and 10 days (median: 6 days); the length of follow-up period was 5-22 months (median: 12.4 months). We believe that laparoscopic treatment of ventral hernias reduces the complication rate, and reduces hospital stay.  相似文献   
86.
BACKGROUND: An increasing proportion of patients undergoing coronary artery bypass grafting (CABG) are diabetics. Patient characteristics, early postoperative outcome, and midterm survival in diabetic patients after CABG were investigated. METHODS: A total of 2779 consecutive patients undergoing isolated CABG during 1995 to 1999 were studied, 19.4% of whom had diabetes mellitus. Demographic and peri-procedural data were registered prospectively in a computerized institutional database. RESULTS: The diabetic group was younger and included a higher proportion of women, and patients with hypertension, triple-vessel disease, and unstable angina. They required a higher number of bypasses, and longer cross-clamp and cardiopulmonary bypass times. Intensive care unit and hospital stays were prolonged and the need for inotropic agents, hemotransfusions, and dialysis was higher in the diabetic group. Renal failure, stroke (4.3% versus 1.7%), mediastinitis, and wound infections were more frequently encountered. Thirty-day mortality was 2.6% versus 1.6% (p = 0.15). Cumulative 5-year survival was 84.4% versus 91.3% (p < 0.001). CONCLUSIONS: Short-term mortality was acceptable in diabetic patients after CABG but they had increased postoperative morbidity in comparison with nondiabetic patients, particularly with regard to renal function, cerebral complications, and infections. Midterm survival was impaired in diabetic patients mainly because of a less favorable outcome in patients treated with insulin.  相似文献   
87.
Preimplantation genetic diagnosis is introduced for prevention of genetic disorders. The combination of in vitro fertilization technique and single cell molecular genetic diagnosis allows only unaffected embryos to be selected for embryotransfer, providing a healthy pregnancy and so also avoiding the need for its possible termination. CASE REPORT: The authors report the first successful case of the clinical application of preimplantation genetic diagnosis in Hungary, resulting the birth of an unaffected baby. Preembryonal biopsy and subsequent fluorescent-PCR analysis of the blastomeres taken from the preembryos of a woman who is a carrier for Duchenne muscular dystrophy was performed. Sexing of the preembryos by X and Y chromosome specific primers were performed and three female preembryos were found. RESULT: All three preembryos were transferred into the uterus, which resulted a singleton pregnancy, resulting the birth of a healthy female baby. The authors are offering preimplantation genetic diagnosis with sexing for couples, who are at risk of having a child with X-linked diseases, or are carriers for the delta-F508 mutation of cystic fibrosis. CONCLUSIONS: The application of this diagnostic tool is also planned for other monogenic disorders.  相似文献   
88.
INTRODUCTION: Heterotaxy syndrome (Ivemark syndrome, or asplenia-polysplenia syndrome) is a heterogeneous group of disease with disturbed body symmetry and malposition of internal organs. Heterotaxy syndrome is caused by the disturbance of the left/right axis in the early embryonic period. AIM OF THE STUDY: The most frequency of heterotaxy syndrome's concomitant anomalies during a five year period in own fetopathology material. MATERIALS AND METHODS: Data of fetopathologic examination of 13 fetuses suffering from prenatally diagnosed heterotaxy syndrome. RESULTS: Situs ambiguus was detected in 9 cases out of 13. In the remaining 4 cases situs inversus totalis was diagnosed. The most frequent and important associated malformation included congenital heart disease was AV channel (10/13) and great vessel anomaly (10/13). CONCLUSION: In cases with prenatally detected complex cardiac anomalies (especially AV channel cases) heterotaxy anomaly must be taken into consideration, with main consequences in prenatal counselling.  相似文献   
89.
Objective: Ischemic stroke is a frequent heterogeneous multifactorial disease that is affected by several genetic mutations and environmental factors. We hypothesised the clinical importance of the co-occurrence of common, unfavorable genetic mutations in the development of different stroke subtypes. Method and material: The Factor V Leiden G1691A (Leiden V), the prothrombin G20210A and the methylenetetrahydrofolate reductase C677T (MTHFR C677T) mutations and the angiotensin-converting enzyme I/D (ACE I/D) and apolipoprotein E (APOE) genotypes were examined by the PCR technique in 689 ischemic stroke patients and 652 stroke-free controls. Logistic regression models were used to estimate the relative risks of different stroke subtypes for different genotype combination patterns. Results: The ACE D/D genotype alone or in combination with the MTHFR 677T or the APOE 4 allele or with both was highly specific for small-vessel infarction. The Leiden V mutation alone or in different combination patterns with the ACE D, APOE 4 and MTHFR 677T alleles was specifically predisposed to large-vessel infarction. The APOE 4 allele alone was calculated to be a general, minor genetic risk factor for ischemic stroke. The MTHFR 677T allele alone was not a risk factor for any stroke subtype. In the different specific predisposition gene combinations, however, both the APOE 4 and MTHFR 677T alleles could increase the relative risk of the given stroke subgroup. Conclusions: Common mutations which alone are minor or non-significant risk factors for ischemic stroke can yield, in specific combination patterns, a highly significant, moderate genetic risk of specific stroke subtypes. Received: 5 February 2002, Received in revised form: 17 April 2002, Accepted: 22 April 2002 Correspondence to Dr. Z. Szolnoki, M. D.  相似文献   
90.
Senile plaques containing beta-amyloid peptide (betaAP) comprise the major neuropathological lesions in Alzheimer's disease (AD). In line with ongoing studies investigating alterations of various biochemical processes of cells of peripheral tissues, the authors demonstrate differences in resting intracellular free calcium levels of lymphocytes harvested from sporadic Alzheimer patients and from age-matched controls. Resting intracellular calcium concentration was measured in Fura-2AM-loaded human lymphocytes by dual wavelength spectrofluorimetry. Resting calcium level appeared to be higher in Alzheimer cells when compared to control lymphocytes. After incubating cells in 10(-7)M of beta-amyloid, the resting calcium concentration of the control cells elevated, while that of Alzheimer lymphocytes did not differ considerably.  相似文献   
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