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61.
62.
Mycoplasmacidal Activity of Peroxidase-H2O2-Halide Systems   总被引:2,自引:2,他引:2       下载免费PDF全文
A mycoplasmacidal system consisting of myeloperoxidase (MPO)-containing granules, H(2)O(2), and a halide is described. In all parameters measured, it appears to be identical to the MPO-H(2)O(2)-halide bactericidal system previously reported. It has a pH optimum of approximately 5.5 and an optimal MPO:H(2)O(2) ratio of 1:25. The halide requirement can be satisfied by either chloride or iodide. Through the use of taurine or horseradish peroxidase substitution, chloride-mediated killing can be distinguished from iodide-mediated killing. The relationship of this mycoplasmacidal system to other mycoplasmacidal systems and to host surveillance of mycoplasma is discussed.  相似文献   
63.
The MM isoenzyme of creatine kinase, a dimer composed of two M ("muscle type") subunits, is found in myocardium, where it constitutes 85% of tissue CK, and in skeletal muscle, where it constitutes virtually 100%, as well as in other tissues. The tissue form is designated MMA. When MMA circulates in plasma, it undergoes stepwise, post-translational modification, mediated by proteolytic enzymes in plasma and giving rise to isoforms called MMB and MMC, which lack carboxy terminal lysine on one or two subunits, respectively. We have shown previously that changes with time in plasma profiles of MM creatine kinase (CK) isoforms in dogs reflect myocardial infarction within 1 hour after the onset of coronary occlusion and permit noninvasive detection of reperfusion within 30 minutes after release of an occlusive coronary arterial ligature. However, analysis of MM CK isoforms in plasma from patients has been hampered by the lack of availability of quantitative as opposed to qualitative methods. This study was performed to develop and validate an assay with the sensitivity and specificity needed for accurate quantification of MM CK isoforms in samples of plasma from patients. A rapid assay procedure will be required ultimately for prospective, clinical use. However, as a first step and for use in development and standardization of rapid assays, a procedure is needed for accurate qualification of isoforms even if its implementation is laborious and slow. The isoform composition of normal plasma was found to comprise 32.0% MMA, 34.9% MMB, and 32.7% MMC.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
64.
The T1 and T2 values of adenocarcinoma EO 771 inoculated into the hind leg of mice are characterized and correlated with the histopathologic state of the tumor. Growth-dependent changes (indicated by a T1 of 630-910 msec and a T2 of 68-185 msec) can be separated into four characteristic phases. The increase in relaxation times in the early phases (A and B) is due to an increasing amount of viable tumor tissue relative to normal muscle tissue. In the later phases (C and D), a decline of the relaxation parameters is observed that is parallel to an increase in the fraction of necrotic tissue. By multiexponential analysis, two relaxation components (indicated by and, respectively) for T1 and T2 and the corresponding fractions alpha 1 and alpha 2 can be observed for both tumor and surrounding muscle tissue. A tissue criterion ("magnetic resonance fingerprint") is defined by a combination of these multiple parameters. This criterion allows separation of not only muscle and tumor tissue but also viable (early state) and necrotic (late state) tumor tissue.  相似文献   
65.
In patients with phenylketonuria (PKU), treated by diet therapy only, evidence suggests that areal bone mineral density (BMDa) is within the normal clinical reference range but is below the population norm. Aims: To study longitudinal bone density, mass, and geometry over 36 months in children with PKU taking either amino acid (L-AA) or casein glycomacropeptide substitutes (CGMP-AA) as their main protein source. Methodology: A total of 48 subjects completed the study, 19 subjects in the L-AA group (median age 11.1, range 5–16 years) and 29 subjects in the CGMP-AA group (median age 8.3, range 5–16 years). The CGMP-AA was further divided into two groups, CGMP100 (median age 9.2, range 5–16 years) (n = 13), children taking CGMP-AA only and CGMP50 (median age 7.3, range 5–15 years) (n = 16), children taking a combination of CGMP-AA and L-AA. Dual X-ray absorptiometry (DXA) was measured at enrolment and 36 months, peripheral quantitative computer tomography (pQCT) at 36 months only, and serum blood and urine bone turnover markers (BTM) and blood bone biochemistry at enrolment, 6, 12, and 36 months. Results: No statistically significant differences were found between the three groups for DXA outcome parameters, i.e., BMDa (L2–L4 BMDa g/cm2), bone mineral apparent density (L2–L4 BMAD g/cm3) and total body less head BMDa (TBLH g/cm2). All blood biochemistry markers were within the reference ranges, and BTM showed active bone turnover with a trend for BTM to decrease with increasing age. Conclusions: Bone density was clinically normal, although the median z scores were below the population mean. BTM showed active bone turnover and blood biochemistry was within the reference ranges. There appeared to be no advantage to bone density, mass, or geometry from taking a macropeptide-based protein substitute as compared with L-AAs.  相似文献   
66.
67.
The characteristics of anxiety-based school refusal were examined in 63 school refusing children and adolescents referred to an outpatient anxiety disorder clinic. Patients were assessed on sociodemographic, diagnostic, and personality variables, as well as familial history of school refusal. Results suggest that there are two primary diagnostic "subgroups" of school refusers--separation anxious and phobic. Phobic school refusers had a later age of onset and showed more pervasive (severe) school refusal than separation anxious school refusers. By contrast, separation anxious school refusers were more likely than phobic school refusers to have mothers who had a history of school refusal problems. The implications of these findings are discussed.  相似文献   
68.
Osteosarcomatosis   总被引:10,自引:0,他引:10  
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.  相似文献   
69.
A population based hybrid design combining element of cohort and cross-sectional approach was used to develop a simple clinical algorithm to predict individual probability of developing hypertension (systolic BP > 140 mm Hg and/or diastolic BP > 90 mmHg). 3615 soldiers initially normotensive at the time of induction into high altitude, were studied by systematic random sampling. Multiple logistic regression analysis showed a high significant association between hypertension and age, body mass index (BMI), tobacco smoking and alcohol consumption. Using the constant/coefficient values obtained from the logistic model and the receiver operating characteristics (ROC) curve analysis, the following predictive rule was developed – To the age in years, add (BMIx 3.86); also add 5.53 if he is a smoker; and add 19.81 if he consumes alcohol. If the total exceeds 142, the individual is at high risk of developing hypertension. This algorithm carries a sensitivity of 68.2% and specificity of 78.5%.KEY WORDS: Hypertension, High altitude  相似文献   
70.
Purpose Nafarelin acetate is a new gonadotropin releasing (GnRH) agonist analogue with unique potency, intranasal administration, and convenient storage. Hence, nafarelin was considered as an alternative for temporary pituitary suppression in patients undergoing ovulation induction in IVF. A crossover treatment in a prospective study was performed including 40 women with bilateral obstructed tubes and normal ovarian function, treated in 80 ovulation induction cycles using the long protocol. Twenty patients used nafarelin acetate 600 g/daily in their first cycle and received d-Trp6-LHRH, 0.5 mg/daily, in their following cycle. The other 20 women used decapeptyl in their first cycle and received nafarelin in the second.Results Estradiol suppression was achieved by both d-Trp6-LHRH and nafarelin at equal time intervals. The average total number of ampoules (P=0.0005) and the length of administration of hMG required for ovarian stimulation (P=0.0002) and the time interval between GnRHa initiation to oocyte retrieval (P=0.04) was significantly lower in nafarelin cycles. The number and the distribution between large and small follicles as well as the average number of oocytes retrieved did not differ between the two GnRH analogues.Conclusion Our results demonstrate that nafarelin acetate is comparable to d-Trp6-LHRH for temporary pituitary suppression used for controlled ovarian stimulation in IVF patients. However, using nafarelin ovarian stimulation was achieved with fewer ampoules of hMG, administered for a shorter period of time, thus with a lesser cost.  相似文献   
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