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SDS-polyacrylamide gel electrophoresis and Western blotting for antibodies reactive with a 64 kDa protein in pig eye muscle membrane was carried out in patients with lid lag and retraction, but no other signs of ophthalmopathy, associated with thyroid disease or nonimmunologic goiter and in patients with Graves' hyperthyroidism without ophthalmopathy who were studied prospectively to determine the relationship of eye muscle antibodies to clinical features of the ophthalmopathy as they appeared in this group of predisposed patients. Seventy-one percent of euthyroid patients with lid lag and retraction but no established ophthalmopathy had detectable serum antibodies to a 64 kDa eye muscle membrane protein. Much smaller proportions had antibodies to proteins of other MW. In normal subjects with previously detectable antibodies to a 64 kDa protein, serum titers, determined by carrying out immunoblotting at serum dilutions of 1:25-1:6400, were low (< or = 1:100) in all cases tested. On the other hand, titers were higher (1:200-1:6400) in 16 of 22 patients with established ophthalmopathy and in 5 of 7 patients with lid lag and retraction tested. Titers tended to be lower in patients with ophthalmopathy of > or = 3 years duration than in those of < or = 1 year duration. Antibody titers were low (1:25) in 6 of 7 patients with Graves' hyperthyroidism without evident eye disease tested. Antibodies to a 64 kDa eye muscle membrane protein were predictive of the development of ophthalmopathy in patients with Graves' hyperthyroidism studied prospectively for periods of 8-42 months.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The ability of technetium (Tc)-99m sestamibi myocardial perfusion imaging at rest to evaluate myocardial infarction and first-pass ejection fraction was studied in a trial involving 18 institutions. Protocol I compared regional perfusion with occurrence of infarction by Q wave or by gated blood pool scan wall motion abnormality in 146 patients. Protocol II assessed first-pass right and left ventricular ejection fraction in 85 patients. In protocol I, Tc-99m sestamibi images were abnormal in 104 of 111 patients (94%) with both a Q wave and a gated scan wall motion abnormality and was normal in 23 of 25 patients (92%) in whom both were normal. Therefore, concordance existed in 105 (94%) patients. Of 115 patients with a Q wave, 107 (93%) had an abnormal Tc-99m sestamibi study. Of 115 patients with a gated scan wall motion abnormality, 108 (94%) had an abnormal Tc-99m sestamibi study. Tc-99m sestamibi imaging showed corresponding perfusion abnormalities in 81% of 69 anterior Q-wave infarcts, 73% of 55 inferior Q-wave infarcts and 88% of 8 posterior infarcts. Specificity in normal regions on electrocardiography and wall motion was 91, 100 and 100%, respectively, for anterior, inferior and posterior regions, respectively, between wall motion and perfusion. Of 17 myocardial segments per patient, there was concordance in 74% of patients. First pass Tc-99m sestamibi imaging of ejection fraction agreed well with conventional first-pass imaging for the right and left ventricle. It is concluded that Tc-99m sestamibi myocardial imaging at rest reliably diagnoses and localizes infarction and assesses ejection fraction by first-pass imaging.  相似文献   
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After 30 years of hematopoietic stem cell use for various indications, umbilical cord blood is considered as an established source of cells with marrow and postmobilization peripheral blood. The limited number of cells still remains a problematic element restricting their use, especially in adults who require to be grafted with a higher cell number. Improving the quality of harvested cord blood, at least in terms of volume and amount of cells, is essential to decrease the number of discarded units. In this review, we examine several variables related to parturient, pregnancy, labor, delivery, collection, the newborn, umbilical cord, and placenta. We aim to understand the biologic mechanisms that can impact cord blood quality. This knowledge will ultimately allow targeting donors, which could provide a rich graft and improve the efficiency of the collection.  相似文献   
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Background

Strong health laboratory systems and networks capable of providing high quality services are critical components of the health system and play a key role in routine diagnosis, care, treatment and disease surveillance. This study aimed to assess the readiness of the national health laboratory system (NHLS) and its capacity to support care and treatment of HIV/AIDS in Tanzania.

Methods

A documentary review was performed to assess the structure of the health system with reference to the status and capacity of the NHLS to support HIV diagnosis. Key informant interviews were also held with laboratory staff in all levels of the health care delivery system in four regions with different levels of HIV prevalence. Information sought included availability and utilization of laboratory guidelines, quality and the capacity of laboratories for diagnosis of HIV.

Results

The findings indicate that a well-established NHLS was in place. However, the coordination of HIV laboratory services was found to be weak. Forty six respondents were interviewed. In most laboratories, guidelines for HIV diagnosis were available but health care providers were not aware of their availability. Utilization of the guidelines for HIV diagnosis was higher at national level than at the lower levels. The low level of awareness and utilization of guidelines was associated with inadequate training and supervision. There was a shortage of human resource, mostly affecting the primary health care level of the system and this was associated with inequity in employment and training opportunities. Laboratories in public health facilities were better staffed and had more qualified personnel than private-owned laboratories.

Conclusion

Tanzania has a well established national health laboratory network sufficient to support HIV care and treatment services. However, laboratories at the primary health care level are constrained by inadequate resources and operate within a limited capacity. Improving the laboratory capacity in terms of number of qualified personnel, staff training on the national guidelines, laboratory diagnostic tools and coordination should be given a higher priority.
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Chitotriosidase activity and CCL18 concentration are interchangeably used for monitoring Gaucher disease (GD) activity, together with clinical assessment. However, comparative studies of these two biomarkers are scarce and of limited sample size. The aim of this systematic review with meta-analysis of individual participant data (IPD) was to compare the accuracy of chitotriosidase activity and CCL18 concentration for assessing type I GD severity. We identified cross-sectional and prospective cohort studies by searching Medline, EMBASE, and CENTRAL from January 1995 to June 2017, and by contacting research groups. The primary outcome was a composite of liver volume >1.25 multiple of normal (MN), spleen volume >5 MN, hemoglobin concentration <11 g/dL, and platelet count <100x109/L. Overall, IPD included 1,109 observations from 334 patients enrolled in nine primary studies, after excluding 111 patients with undocumented values and 18 patients with deficient chitotriosidase activity. IPD were unavailable for 14 eligible primary studies. The primary outcome was associated with a 5.3-fold (95% Confidence Interval [CI]: 4.2-6.6) and 3.0-fold (95% CI: 2.6-3.6) increase of the geometric mean for chitotriosidase activity and CCL18 concentration, respectively. The corresponding areas under the receiver operating characteristics curves were 0.82 and 0.84 (summary difference, 0.02, 95% CI: -0.02 to 0.05). The addition of chitotriosidase activity did not improve the accuracy of the CCL18 concentration. Estimates remained robust in the sensitivity analysis and consistent across subgroups. Neither the chitotriosidase activity nor the CCL18 concentration varied significantly according to a recent history of bone events among 97 patients. In conclusion, the CCL18 concentration is as accurate as chitotriosidase activity in assessing hematological and visceral parameters of GD severity and can be measured in all GD patients. This meta-analysis supports the use of CCL18 rather than chitotriosidase activity for monito-ring GD activity in routine practice.  相似文献   
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