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81.
Effect of nonmedical factors on family physicians' decisions about referral for consultation. 总被引:4,自引:1,他引:3 下载免费PDF全文
G R Langley A M MacLellan H J Sutherland J E Till 《Canadian Medical Association journal》1992,147(5):659-666
OBJECTIVES: To identify nonmedical factors perceived by family physicians (FPs) and consultants as important influences on decisions about referral for consultation, to determine the relative frequency with which such factors are cited and to identify those factors ranked as most important by the FPs and consultants. DESIGN: Survey with semistructured interview between July 1989 and April 1990. PARTICIPANTS: A total of 41 FPs and 20 consultants who were practising or had practised previously in Nova Scotia. INTERVENTIONS: The questionnaire comprised 10 questions: 4 were nondirective "probes" designed to elicit responses without suggesting possible answers, 2 asked the participants to rank such responses in order of importance, and 4 were "prompts" that asked for comments about a list of factors based on a review of the literature. RESULTS: A total of 4845 discrete items were mentioned as being capable of influencing FPs' decisions about referral for consultation. Aggregation of related items resulted in a list of 35 nonmedical factors, of which 11 were identified by at least half the respondents and 14 by less than half but more than 10. These 25 factors fell into three categories: patient and family factors (e.g., patient's wishes), FP and consultant factors (e.g., FP's capabilities), and other influences (e.g., style of practice). On the basis of both frequency of identification and priority scores "patient's wishes" emerged as the most important factor. Two medical factors that were consistently cited--type of problem and age of patient--were thought to interact with the other factors. CONCLUSION: Certain nonmedical considerations may substantially affect physicians' referral practices. 相似文献
82.
Sensory nerve pathology in amyotrophic lateral sclerosis 总被引:2,自引:0,他引:2
T. Heads M. Pollock A. Robertson W. H. F. Sutherland S. Allpress 《Acta neuropathologica》1991,82(4):316-320
Summary A detailed morphometric study was performed on sural nerve biopsies to determine the consistency of sensory nerve pathology in amyotrophic lateral slcerosis (ALS) and to seek a correlation between the severity of peripheral nerve pathology and disease duration. Nerve biopsies from patients with ALS consistently showed evidence of early axonal atrophy, increased remylination and a shift in the diameter distributions curve towards smaller fiber diameters. Importantly, the severity of sensory nerve pathlogy in ALS patients correlated with disease duration. The peripheral nerve sodium pump concentration of patients was not reduced. It is concluded that an ingravescent dorsal root ganglion neuronopathy is seen in the incipient stages of ALS, preferentially affecting the largest neurons and resulting in turn in progressive axonal atrophy, secondary demyelination-remyelination and finally in nerve fiber degeneration. Etiologically, a parallel involvement of motor and sensory neurons suggests a more widespread metabolic disturbance in ALS than simply sick motor neurons.Supported by a grant from the New Zealand Neurological Foundation 相似文献
83.
DL-ethionine Treatment of Adult Pancreatic Donors: Amelioration of Diabetes in Multiple Recipients with Tissue From a Single Donor 下载免费PDF全文
William D. Payne David E. R. Sutherland Arthur J. Matas Phyllis Gorecki John S. Najarian 《Annals of surgery》1979,189(2):248-256
Transplantation of adult rat pancreatic islet tissue as a free graft requires the separation of islet from exocrine tissue to avoid host injury or graft destruction by digestive enzymes. The poor yield from islet isolation techniques currently necessitates the use of multiple donors to ameliorate diabetes in a single recipient. DL-ethionine (DLE) is an agent selectively toxic to the exocrine pancreas. We examined the effect of DLE administration on pancreatic digestive enzyme content and islet mass in adult Lewis rats and the ability of such pancreatic tissue dispersed by collagenase digestion without specific islet isolation to ameliorate diabetes when transplanted to the portal vein of syngeneic rats with streptozotocin induced diabetes. Rats fed normal chow supplemented with 0.5% DLE for 14-20 days showed a logarithmic loss of pancreatic mass. Total pancreatic amylase content declined to 0.3 + 0.1 mg, less than 3% of control values (14.3 +/- 1.0 mg). Total insulin content in DLE treated rats was 87 +/- 8 microg, not significantly different from control rats (101 +/- 7 microg). Histological examination confirmed the selective atrophy of exocrine tissue in DLE treated rats. Fresh pancreatic tissue prepared from a single DLE treated donor ameliorated diabetes 75% of the time when transplanted to one or two recipients and 65% of the time when divided between three of four recipients. Tissue prepared from a single DLE treated donor and stored for 24-48 hours ameliorated diabetes 91% of the time when divided between one or two recipients. Only four of 31 diabetic rats transplanted with fresh pancreatic tissue from untreated adult donors became normoglycemic. Pretreatment of adult rats with DLE induces selective exocrine atrophy, permits dispersed pancreatic tissue from a single donor to ameliorate experimental diabetes in up to four recipients, and allows tissue to be preserved by culture for up to 48 hours without specific islet isolation. 相似文献
84.
J. V. Forrester G. R. Sutherland M. McDonald 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1977,204(2):101-112
Summary Vitreous haemorrhages were induced in rabbits and the echographic appearances on A and B scan were correlated with the gross and histologic appearances over a period of twenty weeks. In all cases, visible vitreous opacities produced distinct echo patterns. As the haemorrhages cleared, the echo amplitudes became progressively weaker. Several patterns of vitreous membranes on B scan were also observed. Pathological examination revealed that such membranes were composed of red cells, macrophages and condensed vitreous collagen. It is suggested that haematogenous vitreous membranes of this type are readily diagnosed by combined A- and B-scan ultrasonic examination, and are probably amenable to surgery. 相似文献
85.
BACKGROUND: The transplant literature has not shown cytomegalovirus (CMV) disease to be a significant risk factor for posttransplant cardiac complications. A large number of nontransplant studies have, however, reported an association between coronary heart disease (CHD) and CMV disease. Pathology studies have demonstrated a high incidence of CMV in atheromatous plaques from the coronary circulation. METHODS: We performed multivariate analysis to determine if posttransplant CMV disease was a significant risk factor for cardiac complications in kidney transplant recipients. We also performed univariate analysis to determine which cardiac complications were more common in the recipients with CMV disease. RESULTS: Between January 1, 1984 and June 30, 1997, 1859 adults underwent kidney transplants at our institution. Of these, 377 developed one of the following cardiac complications posttransplant: myocardial infarction, angina, arrhythmia, congestive heart failure, and angiographic vessel occlusion. By multivariate analysis, significant risk factors for one of the above cardiac complications were recipient age >50 years [odds ratio (OR)=2.5, P=0.0001], diabetes (OR=1.99, P=0.0001), a history of cardiac disease pretransplant (OR= 1.34, P=0.04), and CMV disease (OR=1.5, P=0.01). Univariate analysis demonstrated that recipients with CMV disease had a higher overall incidence of cardiac complications. Arrhythmias, congestive heart failure, and vessel occlusion were more common in those with CMV disease. The incidence of myocardial infarction, angina, and cardiac arrest did not differ between the two groups (recipients with versus without CMV disease). CONCLUSIONS: CMV disease is associated with an increased risk of cardiac complications in kidney transplant recipients. In our series, angiographic vessel occlusion was more common in recipients with CMV disease. This interesting finding may support the theory that CMV plays some role in the pathogenesis of CHD. 相似文献
86.
Living unrelated donors in kidney transplants: better long-term results than with non-HLA-identical living related donors? 总被引:3,自引:0,他引:3
BACKGROUND: Given the severe organ shortage and the documented superior results obtained with living (vs. cadaver) donor kidney transplants, we have adopted a very aggressive policy for the use of living donors. Currently, we make thorough attempts to locate a living related donor (LRD) or a living unrelated donor (LURD) before proceeding with a cadaver transplant. METHODS: We compared the results of our LURD versus LRD transplants to determine any significant difference in outcome. RESULTS: Between 1/1/84 and 6/30/98, we performed 711 adult kidney transplants with non-HLA-identical living donors. Of these, 595 procedures used LRDs and 116 used LURDs. Immunosuppression for both groups was cyclosporine-based, although LURD recipients received 5-7 days of induction therapy (antilymphocyte globulin or antithymocyte globulin), whereas LRD recipients did not. LURD recipients tended to be older, to have inferior HLA matching, and to have older donors than did the LRD recipients (all factors potentially associated with decreased graft survival). Short-term results, including initial graft function and incidence of acute rejection, were similar in the two groups. LURD recipients had a slightly higher incidence of cytomegalovirus disease (P=NS). We found no difference in patient and graft survival rates. However, the incidence of biopsy-proven chronic rejection was significantly lower among LURD recipients (16.7% for LRD recipients and 10.0% for LURD recipients at 5 years posttransplant; P=0.05). LRD recipients also had a greater incidence of late (>6 months posttransplant) acute rejection episodes than did the LURD recipients (8.6% vs. 2.6%, P=0.04). The exact reason for these findings is unknown. CONCLUSION: Although LURD recipients have poorer HLA matching and older donors, their patient and graft survival rates are equivalent to those of non-HLA-identical LRD recipients. The incidence of biopsy-proven chronic rejection is lower in LURD transplants. Given this finding and the superior results of living donor (vs. cadaver) transplants, a thorough search should be made for a living donor-LRD or LURD-before proceeding with a cadaver transplant. 相似文献
87.
Eric Raymond Carmen Kahatt Marie Hélène Rigolet William Sutherland Fran?ois Lokiec Jér?me Alexandre Bertrand Tombal Michael Elman Michael S Lee John R MacDonald Michael Cullen Jean-Louis Misset Esteban Cvitkovic 《Clinical cancer research》2004,10(22):7566-7574
PURPOSE: Irofulven (6-hydroxymethylacylfulvene) is a novel agent, derived from illudin S, with potent apoptotic effects in preclinical models. In the Phase I trial evaluating intermittent weekly schedules, visual symptoms were dose limiting. The aim of this analysis was to better characterize the visual adverse events of irofulven and provide treatment guidelines. EXPERIMENTAL DESIGN: Clinical data from 277 patients entered in single-agent Phase I to II clinical trials who received irofulven on days 1 and 15 every 4 weeks; days 1, 8, and 15 every 4 weeks; or days 1 and 8 every 3 weeks were included in this multiparameter analysis. RESULTS: Overall, 74 patients (27%) experienced visual symptoms. The most frequently reported symptoms were flashing lights (12% of patients), blurred vision (9%), and photosensitivity (8%). Grade 3 toxicity was observed in 12 patients (4%). The incidence and severity of visual events were dose dependent, with no grade 3 visual events occurring at doses < or =0.50 mg/kg and grade 1 to 2 events in only 12% and 8% of patients, at doses of < or =0.50 mg/kg and < or =20 mg/m2, respectively. Grade 1 to 2 toxicity was reversible in most patients. Abnormal electroretinogram and abnormal visual fields were noted after irofulven treatment in 24 of 39 patients (62%) and 15 of 26 patients (58%), respectively. All but 1 patient who had electroretinogram assessment received doses >0.50 mg/kg. Clinical examination and visual field assessment were found to be better correlated with symptoms and appear to be more appropriate for surveillance of irofulven retinal symptoms than electroretinograms. CONCLUSIONS: On the basis of retained antitumor activity and reversibility of grade 1 and 2 visual symptoms at lower doses, it appears that an irofulven dose of < or =0.50 mg/kg or < or =20 mg/m2, not to exceed 50 mg in a single dose, given as a 30-minute infusion on days 1 and 8 every 3 weeks or days 1 and 15 every 4 weeks minimizes the frequency and severity of visual symptoms. 相似文献
88.
Merion RM Henry ML Melzer JS Sollinger HW Sutherland DE Taylor RJ 《Transplantation》2000,70(1):105-111
BACKGROUND: In simultaneous kidney-pancreas (SPK) transplantation, manifestations of renal allograft rejection typically become evident before those of pancreatic rejection. This study compared mycophenolate mofetil (MMF) and azathioprine (AZA) in prevention of renal rejection after primary SPK transplantation. METHODS: In an open-label, randomized, multicenter study, patients received MMF 1.5 g twice daily (n=74) or AZA 1-3 mg/kg daily (n=76) for 1 year after transplantation. The incidence of rejection was assessed at 6 months. Adverse events were tracked through 1 year. Survival data are reported through 2 years. RESULTS: At 6 months, efficacy results for MMF vs. AZA patients, respectively, were the following: rejection (27% vs. 39%); rejection or death (34% vs. 42%); rejection, graft loss, death, or premature withdrawal (i.e., treatment failure; 41% vs. 55%). Six-month efficacy trends favored MMF, and time to rejection or treatment failure was significantly longer when compared with AZA (P=0.049). One-year efficacy results for MMF vs. AZA patients, respectively, were the following: treatment of renal rejection (35% vs. 47%); renal allograft loss or death (9% vs. 12%); pancreas allograft loss or death (15% vs. 14%). Five MMF patients (7%) and four (5%) in the AZA group died. More MMF than AZA patients developed opportunistic infections (54% vs. 38%), but the pathogens did not differ. CONCLUSIONS: Trends for most efficacy parameters favored MMF over AZA, and time to renal allograft rejection or treatment failure was statistically significantly longer for MMF. The use of MMF in the treatment of SPK recipients is a useful advance. 相似文献
89.
BACKGROUND: The increased popularity of pancreas transplants has led to an increased number of potential candidates for retransplants after the initial graft has been lost to technical failure or rejection. We studied a group of recipients who underwent pancreas transplants at a single center to determine whether retransplant recipients were at higher risk of complications. METHODS: Between June 1, 1994, and Dec 31, 1997, a total of 213 pancreas transplants were performed at the University of Minnesota. Of these, 187 were primary transplants and 26 were retransplants. Demographically, the two groups were not significantly different. We analyzed and compared the two groups with respect to incidence of surgical complications, graft survival rates, and patient survival rates. RESULTS: Surgical complications such as bleeding and vascular thrombosis were slightly more common after retransplants, but this trend did not quite reach statistical significance. Infectious complications and leaks were equivalent between the two groups. The incidence of acute rejection was higher after retransplants (P =.02). At 3 years posttransplant, patient survival was no different between the two groups, but pancreas graft survival was lower after retransplants (P =.08). The incidence of early graft loss (by 6 months posttransplant) was significantly higher in retransplant recipients (27% vs 14%, P =.04). CONCLUSIONS: Pancreas retransplants can be performed with a minimal increase in surgical complications. However, graft survival after retransplants is slightly inferior to that after primary transplants, probably for both immunologic and nonimmunologic reasons. Retransplants can be offered to suitable candidates, but they may require more aggressive monitoring for rejection. 相似文献
90.
BACKGROUND: Prolonged preservation of the donor organ may result in delayed graft function or nonfunction after most organ transplants. We studied whether or not prolonged preservation increases surgical complications after pancreas transplants. METHODS: Between January 1, 1994, and September 30, 1998, a total of 294 recipients underwent cadaver pancreas transplants at our institution. Recipients were analyzed in 2 groups: those with pancreas preservation time < or = 20 hours (n = 211) versus > 20 hours (n = 83). RESULTS: Demographic data were similar between the 2 groups, except that mean donor age in the prolonged preservation group was significantly lower. Despite use of younger donors, prolonged preservation was associated with an increased incidence of surgical complications, most notably leaks, thrombosis, and wound infections. Grafts with prolonged preservation were more often noted by the transplant surgeon to be edematous after reperfusion, although the incidence of hyperamylasemia posttransplant did not differ between the 2 groups. Graft and patient survival rates also did not differ between the 2 groups. The incidence of early graft loss (< 3 months) was, however, higher in the prolonged preservation group (20.5% versus 9.0%, P = .04). CONCLUSIONS: Prolonged preservation of the donor organ increases the incidence of surgical complications after pancreas transplants. All attempts should be made to minimize preservation time, keeping it below 20 hours, if possible. 相似文献