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排序方式: 共有870条查询结果,搜索用时 15 毫秒
51.
Raffaele Ferrari Saad Dawoodi Merrill Raju Avinash Thumma Linda S. Hynan Shirin Hejazi Maasumi Joan S. Reisch Sid O'Bryant Marjorie Jenkins Robert Barber Parastoo Momeni 《Neurobiology of aging》2013
Women are at a 2-fold risk of developing late-onset Alzheimer's disease (AD) (onset at 65 years of age or older) compared with men. During perimenopausal years, women undergo hormonal changes that are accompanied by metabolic, cardiovascular, and inflammatory changes. These all together have been suggested as risk factors for late-onset AD. However, not all perimenopausal women develop AD; we hypothesize that certain genetic factors might underlie the increased susceptibility for developing AD in postmenopausal women. We investigated the Androgen Receptor gene (AR) in a clinical cohort of male and female AD patients and normal control subjects by sequencing all coding exons and evaluating the length and distribution of the CAG repeat in exon 1. We could not establish a correlation between the repeat length, sex, and the disease status, nor did we identify possible pathogenic variants. AR is located on the X chromosome; to assess its role in AD, X-inactivation patterns will need to be studied to directly correlate the actual expressed repeat length to a possible sex-specific phenotypic effect. 相似文献
52.
The main objective of the study was to develop a stomach-specific drug delivery system to increase the efficacy of tetracycline against Helicobacter pylori. Chitosan microspheres were prepared by ionic cross-linking and precipitation with sodium sulfate. Two different methods were used for drug loading. In method I, tetracycline was mixed with chitosan solution before the simultaneous cross-linking and precipitation. In method II, the drug was incubated with pre-formed microspheres for 48 h. The cumulative amount of tetracycline that was released from chitosan microspheres and the stability of the drug was examined in different pH medium at 37 degrees C. Microspheres with a spherical shape and an average diameter of 2.0-3.0 microm were formed. When the drug was added to the polymer solution before cross-linking and precipitation only 8% (w/w) was optimally incorporated in the final microsphere formulation. When the drug was incubated with the pre-formed microspheres, on the other hand, a maximum of 69% (w/w) could be loaded. Thirty percent of tetracycline either in solution or when released from microspheres was found to degrade at pH 1.2 in 12 h. The preliminary results from this study suggest that chitosan microspheres can be used to incorporate antibiotic drugs and may be effective when administered locally in the stomach against H. pylori. 相似文献
53.
54.
Objective : Understanding patients' and their parents' perceptions towards asthma medication is important in developing strategies to ensure patient compliance. In this study, parents' perceptions towards their children's use of inhaled medication for asthma treatment were evaluated.
Methodology : A questionnaire was administered by interviewing parents of 210 asthmatic children attending the Department of Paediatrics, National University Hospital.
Results : Our results showed that 76/210 (36%) of parents either felt opposed to inhaler therapy and/or preferred oral medications. The main reasons for their reluctance to use inhalers were related to fear of dependence, side effects and overdosage, and the child's dislike for inhalers. A third of these parents felt that inhalers were only indicated for very severe asthma.
Conclusions : We conclude that a significant proportion of parents have reservations regarding the use of inhalers for the treatment of asthma. These factors should be taken into consideration when planning an effective asthma education programme. 相似文献
Methodology : A questionnaire was administered by interviewing parents of 210 asthmatic children attending the Department of Paediatrics, National University Hospital.
Results : Our results showed that 76/210 (36%) of parents either felt opposed to inhaler therapy and/or preferred oral medications. The main reasons for their reluctance to use inhalers were related to fear of dependence, side effects and overdosage, and the child's dislike for inhalers. A third of these parents felt that inhalers were only indicated for very severe asthma.
Conclusions : We conclude that a significant proportion of parents have reservations regarding the use of inhalers for the treatment of asthma. These factors should be taken into consideration when planning an effective asthma education programme. 相似文献
55.
Objective : To assess the relationship between the subtypes of hypertension in pregnancy and subsequent neonatal haematology.
Methodology : Retrospective review of the haematology of newborns of hypertensive mothers at a tertiary neonatal unit
Results : Over a 2 year period. 249 infants had full blood examinations. Nineteen (7.6%) were neutropenic and 35 (14.1%) thrombocytopenic, including 11 (4.4%) who were both neutropenic and thrombocytopenic. Neutropenia occurred only in infants whose mothers had severe pre-eclampsia and eclampsia or pre-eclampsia with pre-existing hypertension, whereas thrombocytopenia complicated all maternal hypertension subtypes. Two (10%) of the neutropenic infants developed nosocomial infection while seven (20%) of the thrombocytopenic infants bled. Thirteen (68%) of the neutropenic infants compared with 15 (43%) of the thrombocytopenic infants developed their haematological abnormality within 24 h of birth. All but two infants developed the haematological abnormality by the 5th day of life.
Conclusions : Although haematological abnormalities in infants born to hypertensive mothers are uncommon, serious neonatal complications can occur and therefore early haematological screening of these infants is recommended. 相似文献
Methodology : Retrospective review of the haematology of newborns of hypertensive mothers at a tertiary neonatal unit
Results : Over a 2 year period. 249 infants had full blood examinations. Nineteen (7.6%) were neutropenic and 35 (14.1%) thrombocytopenic, including 11 (4.4%) who were both neutropenic and thrombocytopenic. Neutropenia occurred only in infants whose mothers had severe pre-eclampsia and eclampsia or pre-eclampsia with pre-existing hypertension, whereas thrombocytopenia complicated all maternal hypertension subtypes. Two (10%) of the neutropenic infants developed nosocomial infection while seven (20%) of the thrombocytopenic infants bled. Thirteen (68%) of the neutropenic infants compared with 15 (43%) of the thrombocytopenic infants developed their haematological abnormality within 24 h of birth. All but two infants developed the haematological abnormality by the 5th day of life.
Conclusions : Although haematological abnormalities in infants born to hypertensive mothers are uncommon, serious neonatal complications can occur and therefore early haematological screening of these infants is recommended. 相似文献
56.
P Scheffer M Verdier H Hejazi J C Lerondeau B Laborie 《Revue de stomatologie et de chirurgie maxillo-faciale》1985,86(2):87-89
Anterior open-bites may be skeletal, alveolar or mixed. The infra-alveolae is always due to a postural or functional muscular cause and the clinical examination plays an important part in the diagnosis. Delaire's cephalometric analysis can define the type of infra-alveolae. In view of their aetiology, the infra-alveolae require functional re-education, although glossectomy and multiple bands therapy may also be useful. 相似文献
57.
The simplified one-passage technique of culture in irradiated McCoy cells, in conjunction with certain other developments in technique, was used to isolate Chlamydia trachomatis from specimens collected from 78 children with trachoma in Douz, Southern Tunisia. The results show that C. trachomatis is not confined to the upper tarsal area of the conjunctiva in hyperendemic trachoma. The higher isolation rate and corresponding increase in the number of inclusions obtained from swabbings of the upper fornix and lower lid in addition to the conventional collection from the upper tarsus show the superiority of collecting specimens for culture from the whole conjunctiva. Specimens could be collected from the whole conjunctiva by using 1 swab for each eye and pooled for subsequent inoculation, so that the laboratory incurred no additional work. A close correlation was observed between isolation rate, together with the number of inclusions, obtained in cell culture, and intensity of inflammatory disease in hyperendemic trachoma. The sensitivity and practicability of this cultural test should provide a valuable laboratory index for use in epidemiological and therapeutic studies of trachoma. 相似文献
58.
T cell repertoire scanning is promoted by dynamic dendritic cell behavior and random T cell motility in the lymph node 总被引:26,自引:0,他引:26 下载免费PDF全文
Miller MJ Hejazi AS Wei SH Cahalan MD Parker I 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(4):998-1003
Dendritic cells (DCs) ingest antigens in peripheral tissues and migrate to lymph nodes where they present MHC class II-bound antigen to CD4(+) T cells. We used two-photon microscopy to image the single-cell dynamics of interactions between DCs and T cells within intact lymph nodes in the absence of relevant antigen. DCs were fluorescently labeled in vivo by cutaneous injection of alum adjuvant including carboxyfluorescein diacetate succinimidyl ester (CFSE). CFSE-positive DCs (CD11c(+), CD11b(+), and low-to-intermediate CD8(+)) were observed in draining lymph nodes 24-72 h later. Labeled DCs meandered slowly (2-3 microm x min(-1)) in the T cell zone near B cell follicles but vigorously extended long agile dendrites. Encounters between T cells and DCs arose as T cells moved autonomously along random paths. Moreover, T cells did not accumulate around DCs, and their relative velocities approaching and departing DCs were equivalent, implying that T cells are not attracted toward DCs by chemotactic gradients but rather encounter them by chance. T cell/DC contacts occurred primarily on dendrites at arm's length from the DC soma and typically lasted approximately 3 min, enabling an individual DC to interact with up to 5000 T cells per hour. We conclude that dynamic DC gesticulation and random T cell motility together enhance the stochastic scanning of the T cell repertoire, thereby enabling rapid initiation of the immune response. 相似文献
59.
Severe head injuries in children (under 15 years of age) have many features that differentiate them from head injuries in adults. In such cases, non-surgical treatment cannot always prevent fatal herniation. We report on seven cases of children with severe head injury, presenting with decorticate posturing and treated by unilateral decompressive craniectomy. The aim of the unilateral decompressive craniectomy was to decompress the midbrain and the brainstem. Post-operatively, all patients showed good recovery within 5 weeks (Glasgow Coma Scale score 15). The alternative treatment modalities are discussed critically in an attempt to determine the value of the unilateral decompressive craniectomy procedure and to define the clinical parameters that might identify those children most likely to benefit from this technique. CONCLUSION: the unilateral decompressive craniectomy has an advantage over non-surgical treatment of children with severe brain injury and should be considered in their management. 相似文献
60.
Neurologic outcome after decompressive craniectomy in children 总被引:1,自引:0,他引:1