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171.

Background  

Population antimicrobial use may influence resistance emergence. Resistance is an ecological phenomenon due to potential transmissibility. We investigated spatial and temporal patterns of ciprofloxacin (CIP) population consumption related to E. coli resistance emergence and dissemination in a major Brazilian city. A total of 4,372 urinary tract infection E. coli cases, with 723 CIP resistant, were identified in 2002 from two outpatient centres. Cases were address geocoded in a digital map. Raw CIP consumption data was transformed into usage density in DDDs by CIP selling points influence zones determination. A stochastic model coupled with a Geographical Information System was applied for relating resistance and usage density and for detecting city areas of high/low resistance risk.  相似文献   
172.
173.
Hepatocellular carcinoma and cholangiocarcinoma are primary liver cancers, both represent a growing challenge for clinicians due to their increasing morbidity and mortality.In the last few years a number of in vivo models of hepatocellular carcinoma and cholangiocarcinoma have been developed. The study of these models is providing a significant contribution in unveiling the pathophysiology of primary liver malignancies. They are also fundamental tools to evaluate newly designed molecules to be tested as new potential therapeutic agents in a pre-clinical set. Technical aspects of each model are critical steps, and they should always be considered in order to appropriately interpret the findings of a study or its planning.The purpose of this review is to describe the technical and experimental features of the most significant rodent models, highlighting similarities or differences between the corresponding human diseases. The first part is dedicated to the discussion of models of hepatocellular carcinoma, developed using toxic agents, or through dietary or genetic manipulations. In the second we will address models of cholangiocarcinoma developed in rats or mice by toxin administration, genetic manipulation and/or bile duct incannulation or surgery. Xenograft or syngenic models are also proposed.  相似文献   
174.
Picus  D; Marx  MV; Hicks  ME; Lang  EV; Edmundowicz  SA 《Radiology》1989,173(2):487-491
Surgical cholecystectomy is associated with a high morbidity and mortality in elderly patients with acute calculous cholecystitis and underlying cardiac or pulmonary disease. Currently there are few alternatives for treating these patients. The authors have used percutaneous cholecystolithotomy in 11 such high-risk patients for definitive treatment of gallbladder calculi. In all 11 patients all stones were successfully removed from the gallbladder and cystic duct. The entire procedure--from initial tube placement to final tube removal--lasted 17-40 days (mean, 21 days). There were two complications: one minor--local wound infection--and one major--bile peritonitis with eventual death. Percutaneous cholecystolithotomy is an effective alternative therapy for acute calculous cholecystitis in elderly, debilitated patients.  相似文献   
175.
Interventional radiologists: occupational radiation doses and risks   总被引:2,自引:0,他引:2  
Niklason  LT; Marx  MV; Chan  HP 《Radiology》1993,187(3):729
  相似文献   
176.
The purpose of the present study was to determine the cumulative likelihood of pregnancy success after repetitive cycles of oocyte donation and specifically to examine the influence of recipient age and diagnosis upon the cumulative likelihood of pregnancy in an effort to identify any potential subgroup of recipients who might have diminished endometrial receptivity. We retrospectively analysed the outcome of 418 consecutive embryo transfer cycles among 276 recipients of oocyte donation in our institution. We analysed clinical pregnancy and delivery rates in the recipients divided by age groups and diagnostic groups. For the purpose of life-table analysis, only cycles prior to and including the first cycle producing a successful pregnancy were included. Frozen-thawed embryo transfers were not included in the analysis. The overall clinical pregnancy rate was 36.2% (95% CI 31-41%) and the cumulative pregnancy rate after four cycles was 87.9%. The overall delivery rate was 29.3% (95% CI 25-33%) and the cumulative delivery rate after four cycles was 86.1%. There were no statistically significant differences in any of the rates attributable to recipient age or diagnosis. No decline in per cycle success was noted over consecutive cycles. We conclude that neither recipient age nor diagnosis plays a substantial role in the success of oocyte donation, implying that endometrial receptivity is unaltered by age or diagnosis. Furthermore, up to four successive cycles of oocyte donation are associated with the same probability of success.   相似文献   
177.
We tested the feasibility of performing outpatient laparoscopic surgery to reverse tubal sterilization using titanium staples to reapproximate the oviducts. A total of 14 women underwent the procedure which involved excision of the tubal eschar, stenting of the severed remnants, and circumferential stapling of the muscularis and serosa. Reapproximation was possible in all cases, with a measured tubal length post-anastomosis of 4.5 +/- 0.5 cm (range 3.0-7.0 cm). The length of operating time was 2.8 +/- 0.2 h (range 2.2-3.8 h), and all patients were discharged the same day. There were no operative complications, and no readmissions were necessary. Within 6 months of surgery there were six pregnancies including one spontaneous abortion and five ongoing pregnancies. Of those not conceiving within 8 months, seven (100%) demonstrated tubal patency on a follow-up hysterosalpingogram. We conclude the laparoscopic approach to tubal sterilization reversal is a viable alternative to open abdominal microsurgical approaches. Although preliminary, laparoscopic surgery promises to be cost effective, as it can be performed on an outpatient basis, may reduce operative time and minimizes the recuperative period of patients.   相似文献   
178.

Background  

Prioritisation instruments were developed for patients on waiting list for hip and knee arthroplasties (AI) and cataract surgery (CI). The aim of the study was to assess their convergent and discriminant validity and inter-observer reliability.  相似文献   
179.
180.
The activation marker CD30 is expressed on the cell surface of the malignant cells in Hodgkin's disease and a few non-Hodgkin lymphomas. We have analyzed the regulation of membrane-bound CD30 and found that the binding of a variety of anti-CD30 antibodies induced down-regulation of CD30 on cell lines. In addition, such down-modulation was also observed after treatment of the cell surface proteins with the sulfhydryl reagent iodoacetamide or after stimulation of the second messenger pathway with phorbol ester or calcium ionophore. This modulation was abolished at 4°C and strongly inhibited by chelators like EDTA or 1, 10-phenanthroline, whereas EGTA, a selective inhibitor of Ca2+-dependent proteinases and other inhibitors of serine, thiol and acid proteinases, showed no effect. The down-modulation was strengthened by Zn2+ or Cd2+, but not by other divalent cations such as Fe2+, Mn2+, Mg2+, Ca2+ or Co2+, thus indicating the involvement of a zinc metalloproteinase in CD30 modulation which can be activated by protein kinase C and by alkylation of sulfhydryl groups. Pulse-chase experiments, analysis of the CD30 glycosylation and specific measurement of the 90-kDa soluble form of CD30 (sCD30) with a sandwich radioimmunoassay revealed that CD30 down-modulation results from enhanced release of 90-kDa sCD30 by the site-specific cleavage of CD30 accomplished by a zinc metalloproteinase. This release occurs at the cell membrane without prior endocytosis. © 1995 Wiley-Liss, Inc.  相似文献   
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