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91.
Human granulocyte-macrophage colony stimulating factor (GM-CSF) has been synthesized in high yield using a temperature inducible plasmid in Escherichia coli. The human GM-CSF is readily isolated from the bacterial proteins because of its differential solubility and chromatographic properties. The bacterially synthesized form of the human GM-CSF contains an extra methionine residue at position 1, but otherwise it is identical to the polypeptide predicted from the cDNA sequence. The specific activity of 2.9 X 10(7) units/mg of protein for purified bacterially synthesized human GM-CSF indicates that despite the lack of glycosylation, the molecule is substantially in its native conformation. This molecule stimulated the same number and type of both seven- and 14-day human bone marrow colonies as the CSF alpha preparation from human placental conditioned medium. Human GM-CSF had no activity on murine bone marrow or murine leukemic cells. There was no detectable, direct stimulation of adult human erythroid burst forming units (BFU-E) by the bacterially synthesized human GM-CSF. Although impure preparations containing native human GM-CSF (eg, human placental conditioned medium) stimulated the formation of mixed colonies, even in the presence of erythropoietin, the bacterially synthesized human GM-CSF failed to stimulate the formation of mixed colonies from adult human bone marrow cells. The bacterially synthesized human GM-CSF increased N-formyl-methionyl-leucyl- phenylalanine (FMLP)-induced superoxide production and lysozyme secretion. Antibody-dependent cytotoxicity and phagocytosis by human neutrophils was stimulated by the bacterially synthesized human GM-CSF and eosinophils were also activated in the antibody-dependent cytotoxicity assay.  相似文献   
92.
SUMMARY Four hundred consecutive diabetic patients had their mid-arm circumference (AC) measured and body mass index (BMI) calculated to determine the proportion of an unselected clinic group who would require a larger than standard adult blood pressure (BP) cuff and whether or not BMI could be used to predict AC and hence choice of appropriate BP cuff size. More than 75% of both men and women had an AC ≥29cm, justifying a larger than standard adult cuff for their BP measurement. When patients were classified according to their BMI, at least 80% with a BMI ≥30 and more than 70% with a BMI of 25-29 had a measured AC ≥29cm, while less than a third of patients with a BMI ≥25 had an AC ≥29cm. These results indicate that, in a diabetic clinic, most patients with a BMI ≥25 are likely to require an alternative adult BP cuff if their blood pressure is to be measured precisely.  相似文献   
93.

Introduction  

Neurologic disorders with autoimmune dysregulation are commonly encountered in the critical care setting. Frequently encountered diseases include Guillain–Barré syndrome (GBS), myasthenia gravis, multiple sclerosis, acute demyelinating encephalomyelitis, and encephalitides. Immunomodulatory therapies, including high-dose corticosteroids, plasmapheresis, and intravenous immunoglobulins, are the cornerstone of the treatment of these diseases. Here we review the efficacy and side effects of immunomodulatory therapies commonly utilized in critically ill neurologic patients in the intensive care setting.  相似文献   
94.
High tibial osteotomy (HTO) is an established treatment option for isolated medial osteoarthritis in young and active patients. One important factor for success of this procedure is the degree of correction of the weight-bearing line. Computer-assisted navigation systems are believed to improve the precision of axis correction through intraoperative real-time monitoring. This study investigates the precision of correction of the weight-bearing line in open-wedge HTO with and without a navigation system.Nineteen legs of well-preserved human cadaver were randomly assigned to navigated (n = 10) or conventional (n = 9) HTO. In order to achieve a sufficient amount of correction in all legs the weight-bearing line was aimed at 80 percent of the width of the tibial plateau.The mean deviation of the weight-bearing line from the desired 80 percent was 1 percent in the navigated and 8.6 percent in the conventional operated legs (p = 0.002). The weight-bearing line of all navigated but only 5 of the 9 conventional operated legs was within a ± 5 percent tolerance level (p = 0.33).Navigated open-wedge HTO achieved better correction of the weight-bearing line than the conventional method in human cadaver legs. Future studies have to prove this advantage in a clinical setting and it''s effect on patient outcome.  相似文献   
95.

Background:

Vision loss after spinal surgery is a rare and devastating complication. Risk factors include patient age, operative time, estimated blood loss, and intraoperative fluid management. Children with spinal cord injury often develop scoliosis that requires surgical correction.

Study Design:

Case report.

Methods:

Clinical and radiographic review was conducted of a 15-year-old boy who developed severe scoliosis after sustaining a C5 level injury at age 4 years from a motor vehicle crash.

Findings:

The patient underwent a posterior spinal fusion from T2 to the pelvis, and good correction of the spinal deformity was attained. During the 8-hour procedure, blood loss was 4,000 mL (approximately 1.2 blood volumes) and 17,000 mL of fluids were administered. On postoperative day 5, it was determined that the patient had complete visual loss. Neuro-ophthalmology consultation confirmed the diagnosis of posterior ischemic optic neuropathy.

Conclusions:

A significant number of children with spinal cord injury develop scoliosis requiring surgical correction. These procedures are often lengthy, with the potential for extensive blood loss and fluid shifts, factors that may increase the likelihood of postoperative vision loss. Patients should be counseled about this complication, and the surgical and anesthesiology teams should take all measures to minimize its occurrence.  相似文献   
96.
Hereditary hearing loss accounts for nearly 60% of deafness in developed countries and about 30% of them are syndromic. Pierre Robin Syndrome is one such condition. The patient with this syndrome usually presnts with triad of micrognathia, glossoptosis and cleft palate. Hearing loss is mostly conductive but there can be sensorineural hearing loss also. Here we present a case of Pierre Robin Syndrome who presented with congenital hearing loss. He also had bilateral serous otitis media. He underwent cochlear implant surgery and was prescribed antihistaminics and steroid spray for middle ear effusion. Therefore, proper clinical evaluation is required.  相似文献   
97.
AIM: To compare the histologic features of the liver in intrahepatic neonatal cholestasis (IHNC) with infectious, genetic-endocrine-metabolic, and idiopathic etiologies. METHODS: Liver biopsies from 86 infants with IHNC were evaluated. The inclusion criteria consisted of jaundice beginning at 3 mo of age and a hepatic biop- sy during the 1st year of life. The following histologic features were evaluated: cholestasis, eosinophilia, giant cells, erythropoiesis, siderosis, portal fibrosis, and the presence of a septum. RESULTS: Based on the diagnosis, patients were classified into three groups: group 1 (infectious; n = 18), group 2 (genetic-endocrine-metabolic; n = 18), and group 3 (idiopathic; n = 50). There were no significant differences with respect to the following variables: cholestasis, eosinophilia, giant cells, siderosis, portal fibrosis, and presence of a septum. A significant dif- ference was observed with respect to erythropoiesis, which was more severe in group 1 (Fisher's exact test, P = 0.016). CONCLUSION: A significant difference was observed in IHNC of infectious etiology, in which erythropoiesis was more severe than that in genetic-endocrine-meta- bolic and idiopathic etiologies, whereas there were no significant differences among cholestasis, eosinophilia, giant cells, siderosis, portal fibrosis, and the presence of a septum.  相似文献   
98.
Patients frequently present to the ED with drug overdose and reduced conscious level leading to coma. There is considerable practice variation around which patients require intubation. Indications include: (i) respiratory failure (including airway obstruction); (ii) to facilitate specific therapies or intubation as a therapy in itself; and (iii) for airway protection in the unprotected airway. We argue that intubating a patient purely for (iii) is outdated and that most patients can be safely observed. There is a paucity of good quality research in the area of drug overdose with reduced consciousness. Teaching may be outdated and based on the use of the Glasgow Coma Scale in head trauma. Current low quality research suggests observation is safe. We recommend that patients undergo an individualised risk assessment of the need for intubation. We propose a flow diagram to aid clinicians in safely observing comatose overdose patients. This can be applied if the drug is unknown, or there are multiple drugs involved.  相似文献   
99.
The objective of this study was to assess the cost of caring for patients with psoriasis in Italy according to the AISP study (Associazione Italiana Studi Psoriasi or Italian Association for Studies on Psoriasis), involving 104 university and hospital centres and 7992 patients in 1994. The mean yearly cost of care for a single patient was calculated at 905 Euros. Hospitalization accounted for more than four-fifths of the costs, therapy for about one-eighth (systemic therapies were the most expensive) and office visits and day hospitals for the remainder. In our study series less than 20% of patients accounted for more than 90% of the total costs.  相似文献   
100.
Wolf-Hirschhorn syndrome (WHS) is a malformation syndrome associated with a hemizygous deletion of the distal short arm of chromosome 4 (4p16.3). The smallest region of overlap between WHS patients, the WHS critical region, has been confined to 165 kb, of which the complete sequence is known. We have identified and studied a 90 kb gene, designated as WHSC1 , mapping to the 165 kb WHS critical region. This 25 exon gene is expressed ubiquitously in early development and undergoes complex alternative splicing and differential polyadenylation. It encodes a 136 kDa protein containing four domains present in other developmental proteins: a PWWP domain, an HMG box, a SET domain also found in the Drosophila dysmorphy gene ash -encoded protein, and a PHD-type zinc finger. It is expressed preferentially in rapidly growing embryonic tissues, in a pattern corresponding to affected organs in WHS patients. The nature of the protein motifs, the expression pattern and its mapping to the critical region led us to propose WHSC1 as a good candidate gene to be responsible for many of the phenotypic features of WHS. Finally, as a serendipitous finding, of the t(4;14) (p16.3;q32.3) translocations recently described in multiple myelomas, at least three breakpoints merge the IgH and WHSC1 genes, potentially causing fusion proteins replacing WHSC1 exons 1-4 by the IgH 5'-VDJ moiety.   相似文献   
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