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161.
The management of rectal cancer presents substantial challenges. Patients with T3 and/or node-positive rectal cancers are at high risk for local failure and distant metastases (DM). Adjuvant radiation has been shown to decrease local recurrence (LR) rates; however, this local therapy has not been demonstrated to improve survival when compared to surgery alone. In several prospective randomized trials adjuvant chemoradiation with 5-fluorouracil-(5-FU)-based chemotherapy improved LR rates, DM rates, and overall survival (OS). The optimal chemotherapeutic regimen has not been determined; however, studies comparing standard IV bolus 5-FU administration with continuous infusion (CI) 5-FU demonstrated that CI administration was superior. Preoperative therapy has potential advantages over adjuvant therapy such as less acute bowel toxicity and improved sphincter preservation. Preoperative chemoradiation has been shown in several studies to improve LR rates and OS when compared to surgery alone. Our current approach to patients with resectable T3 or N1 cancer in the distal two-thirds of the rectum on preoperative staging is preoperative chemoradiation with planned postoperative chemotherapy. This regimen offers the best chance for local control and disease-free survival while potentially downstaging the tumor and improving sphincter preservation. 相似文献
162.
V. Conter B. Tschümperlin B. Gridelli A. Lucianetti S. Ascani D. Bauer R. Burnelli S. Poggi V. Ramaccioni M. Milani S. A. Pileri 《Annals of oncology》1998,9(6):673-676
Here we describe the case of a 14-year-old boy who underwent livertransplantation for post-Kasai biliary atresia when aged 4. Antirejectiontreatment consisted of prednisone and cyclosporine. At the age of 11 years thepatient developed left cervical lymphadenopathy; the biopsy showed classicalHodgkin's disease(HD) of the mixed cellularity (MC) type. Neoplastic cellsexpressed CD30 and CD15, and were negative for CD45, CD20, CD3, CD43, andCD79a. Furthermore, they carried the EBV-related products LMP1 and EBER1/2.Treatment consisted of three cycles of adriamycin, bleomycin, vinblastine andDTIC (ABVD), followed by radiotherapy (2,000 cGys) on involved fields. Atpresent, 42 months after the diagnosis of HD, the patient is still in completeremission. This is, to the best of our knowledge, the first reported case ofclassical HD following liver transplantation. The positivity of neoplasticcells for LMP1 and EBER1/2 indicates a possible role for immunosuppression inthe development of the tumor, and whether a reduction in immunosuppressionmight have influenced the course of the disease is open to question. 相似文献
163.
164.
J. Wikström D. W. Meyer K. Eickhoff G. Ritter S. Poser H. J. Bauer V. Kratzsch W. R. Kiessling 《Journal of neurology》1977,216(1):47-50
Summary The serological responses of 195 multiple sclerosis (MS) patients and 251 controls were tested against 6/94-parainfluenza virus, which was previously isolated from brain tissue of two patients with MS. The hemagglutination-inhibition titers of 1:128 were found more frequently in MS patients (21.5%) than in controls (14.0%). However, the geometric mean titers did not differ between these two groups. The present study concludes that a causal relationship of 6/94-virus to MS, based on a specific immune response, is improbable, although it does not exclude the possibility of a pathogenetic significance of the agent in the cases from which the autopsy material was derived.Supported by Deutsche Forschungsgemeinschaft (Schwerpunkt Ätiologie und Pathogenese der Multiplen Sklerose und verwandter Erkrankungen) 相似文献
165.
A HPLC method using reversed-phase columns is described for the determination and isolation of phorbolesters in crotonoil. The identification of the compounds is based on an off-line combination of HPLC-MS, as well as on fatty acid analysis by GC. With this method several new phorbolesters of crotonoil could be detected. This method is also suitable for the determination of phorbol- or similar diterpenesters in other Euphorbiaceae. 相似文献
166.
Georg Bauer Susanne Kahl Iva Singh Sawhney Petra Hfler Ralph Gerspach Bertfried Matz 《International journal of cancer. Journal international du cancer》1992,51(5):754-760
Studies on the mechanisms of transformation of mammalian cells by herpes simplex virus (HSV) in vitro have been prevented so far by the extremely low transformation frequencies obtained in monolayer culture. Here we present a transformation system that relies on the direct seeding in soft agar of infected single cells, thus avoiding negative interactions between normal and transformed cells. We took advantage of HSV-I temperature-sensitive mutants at the UL9 locus, which codes for a DNA-binding protein necessary for viral DNA replication. At the non-permissive temperature, viral DNA synthesis and late gene expression are prevented. Viral gene expression is restricted to immediate early and early genes. Induction of transformation was highly efficient in our one-step transformation system. It depended on intact viral particles and viral DNA. Immediate early and/or early viral gene expression was sufficient to induce transformation. Colonies were stably transformed and did not show any rescue of viable virus after temperature downshift and co-cultivation with susceptible cells. Transformed cells maintained the transformed state in the absence of viral DNA. Our data therefore support the "hit-and-run" hypothesis for the transforming effect of HSV. 相似文献
167.
N G Kasabian S B Bauer F M Dyro A H Colodny J Mandell A B Retik 《American journal of diseases of children (1960)》1992,146(7):840-843
OBJECTIVE--To determine if prophylactic use of clean intermittent catheterization and oxybutynin chloride is effective in preventing urinary tract deterioration in myelodysplastic children with high bladder pressure and detrusor-sphincter dyssynergia. DESIGN--Sequential, nonrandomized trial. SETTING--Referral-based urodynamics facility and myelodysplasia program at a major city pediatric hospital. PARTICIPANTS--Twenty-six of 71 consecutive newborns with myelodysplasia who exhibited these urodynamic findings were treated prophylactically over 5 years, whereas 56 of 105 consecutive newborns with the same findings treated during the previous 7 years were treated expectantly. INTERVENTION--Clean intermittent catheterization and oxybutynin therapy were begun when these specific urodynamic findings were detected. MEASUREMENTS AND RESULTS--Follow-up urodynamic studies and roentgenographic assessment of the urinary tract were performed periodically over 5 years. Oxybutynin eliminated uninhibited contractions in two of 14 newborns and lowered peak contractile pressure in the remaining 12. Oxybutynin also lowered bladder-filling pressure at capacity in all 12 additional neonates with only hypertonicity. Twenty-four (92%) of 26 children had normal kidney function and drainage during the observation period, two (8%) developed hydroureteronephrosis, and one of these two had vesicoureteral reflux. In a prior study of children similarly at risk who were treated expectantly, the roentgenographic appearance of the upper urinary tract had changed in 48%. Minimal side effects were noted with oxybutynin, and no adverse effects of clean intermittent catheterization were detected. CONCLUSIONS--Oxybutynin effectively reduces uninhibited contractions and lowers detrusor filling pressure, while clean intermittent catheterization allows bladder emptying at low pressures with no measurable side effects in these neonates. The overall effect maintains the integrity of the upper urinary tract in almost all myelodysplastic children at risk of urinary tract deterioration. Expectant therapy can no longer be advocated when these "at risk" children are identified because prophylactic treatment is so effective. 相似文献
168.
G. W. Stevenson Steven C. Hall Bruce S. Bauer Frank A. Vicari Frank L. Seleny 《Journal canadien d'anesthésie》1991,38(8):1046-1049
Miller's syndrome is a rare congenital disorder with facial features similar to that of Treacher-Collins syndrome. This report details the anaesthetic management of an infant during multiple surgical procedures, beginning with pylormyotomy at one month of age. Airway management was difficult because of severe micrognathia and was accomplished using an awake intubation with a conventional straight blade modified for continuous administration of oxygen ("oxyscope"). Due to recurrent upper airway obstruction and the anticipated need for multiple surgical procedures in the first years of life, a tracheostomy was placed. Because of the multiple airway, orthopaedic, and nutritional difficulties, it is important that a prospective, multidisciplinary approach be used in these patients' care. Consideration should be given to early tracheostomy for airway maintenance. 相似文献
169.
Nancy Telfer Yeu-Tsu N. Lee Quenious Merrill Franz K. Bauer 《Journal of surgical oncology》1981,16(2):159-165
The red blood cell (RBC) uptake of rubidium-86 (Rb-86), a sensitive in vitro test of RBC membrane transport, was measured in 22 controls, 8 patients with benign breast lesions, and 30 stage I/II, 13 stage III/IV untreated breast cancers. Total Rb-86 transport was measured. Following ouabain block, passive transport was determined, allowing calculation of active Rb-86 uptake by difference. There was a significant decrease in total and passive uptake by RBCs from patients with breast cancer when compared to controls and those with benign lesions (total uptake 58.6 ± 6.1% versus 63.6 ± 3.9%, P < 0.01; passive uptake 38.7 ± 6.8% versus 42.7 ± 4.6%, P < 0.02). The Rb-86 uptake returned towards normal in successfully treated stages-II-to-IV patients. There were no correlations with the patient's age, hematocrit, or incubation hematocrit with RBC Rb-86 uptakes. Results from incubation in Krebs-Ringer solution were not consistent with a plasma blocking factor. The RBC potassium content was slightly increased in the cancer patients. This, along with decreased passive transport, eliminates the nonspecific malfunction of the Na-K-pump as an explanation, and suggests that the decreased uptake is a cancer-related phenomenon. 相似文献
170.
Heiss WD Kracht L Grond M Rudolf J Bauer B Wienhard K Pawlik G 《Stroke; a journal of cerebral circulation》2000,31(2):366-369
BACKGROUND AND PURPOSE: Central benzodiazepine receptor ligands, such as [(11)C]flumazenil (FMZ), are markers of neuronal integrity and therefore might be useful in the differentiation of functionally and morphologically damaged tissue early in ischemic stroke. We sought to assess the value of a benzodiazepine receptor ligand for the early identification of irreversible ischemic damage to cortical areas that cannot benefit from reperfusion. METHODS: Eleven patients (7 male, 4 female, aged 52 to 75 years) with acute, hemispheric ischemic stroke were treated with alteplase (recombinant tissue plasminogen activator; 0.9 mg/kg according to National Institute of Neurological Disorders and Stroke protocol) within 3 hours of onset of symptoms. At the beginning of thrombolysis, cortical cerebral blood flow ([(15)O]H(2)O) and FMZ binding were assessed by positron emission tomography (PET). Those early PET findings were related to the change in neurological deficit (National Institutes of Health Stroke Scale) and to the extent of cortical damage on MRI or CT 3 weeks after the stroke. RESULTS: Hypoperfusion was observed in all cases, and in 8 patients the values were below critical thresholds estimated at 12 mL/100 g per minute, comprising 1 to 174 cm(3) of cortical tissue. Substantial reperfusion was seen in most of these regions 24 hours after thrombolysis. In 4 cases, distinct areas of decreased FMZ binding were detected. Those patients suffered permanent lesions in cortical areas corresponding to their FMZ defects (112 versus 146, 3 versus 3, 2 versus 1, and 128 versus 136 cm(3)). In the other patients no morphological defects were detected on MRI or CT, although blood flow was critically decreased in areas ranging in size up to 78 cm(3) before thrombolysis. CONCLUSIONS: These findings suggest that imaging of benzodiazepine receptors by FMZ PET distinguishes between irreversibly damaged and viable penumbra tissue early after acute stroke. 相似文献