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81.
Treatment of Dysoxylum pure triterpenes 3beta,24,25-trihydroxycycloartane and beddomei lactone to the rice leaffolder (RLF), Cnaphalocrocis medinalis (Guenée) (Lepidoptera: Pyralidae), resulted in prolonged larval duration and reduced larval weight. In leaf cut choice assay and topical application experiments, beddomei lactone and 3beta,24,25-trihydroxycycloartaneto showed strong antifeedant and growth inhibitor activity against fourth instar larvae of C. medinalis. Also average leaf consumption was decreased (89%) by the treatment of the two terpinoids when compared with controls. Number of eggs laid by the female (fecundity) was decreased and oviposition deterrence index was increased due to the treatment. This result further shows that the pure triterpenes of Dysoxylum act as both an antifeedant and chronic toxin to the rice leaffolder larvae.  相似文献   
82.
The vehicles used to carry calcium hydroxide intracanal medicament are many and may affect the retrieval. Access cavities were prepared in 40 single rooted anterior teeth, cleaning and shaping was done and filled with either Metapex or pure calcium hydroxide powder in distilled water. After 7 days the calcium hydroxide was retrieved using either 17% EDTA or 10% citric acid in combination with ultrasonic agitation. Volume analysis was done using spiral computed tomography. The percentage difference was calculated and statistically analyzed using Kruskal-Wallis and Mann-Whitney U test. 10% citric acid showed better removal efficiency than 17% EDTA for Metapex (p = 0.003). The 17% EDTA showed excellent removal efficiency of powder form of calcium hydroxide in distilled water than Metapex (p < 0.001). Ten percent citric acid removed powder form of calcium hydroxide in distilled water better than Metapex (p = 0.05).  相似文献   
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84.
BACKGROUND: Concern exists that prednisone-free maintenance immunosuppression in kidney transplant recipients will increase acute and/or chronic rejection. METHODS: From October 1, 1999, through February 29, 2004, at our center, 477 kidney transplant recipients (341 living donor, 136 cadaver) discontinued prednisone on postoperative day 6, per our protocol. Immunosuppression consisted of polyclonal antibody (Thymoglobulin) for 5 days, prednisone intraoperatively and for 5 days, a calcineurin inhibitor, and either sirolimus or mycophenolate mofetil. We compared outcome with that of historical controls who did not discontinue prednisone. RESULTS: The recipients on prednisone-free maintenance immunosuppression had excellent 4-year actuarial patient survival (92%), graft survival (90%), acute rejection-free graft survival (86%), and chronic rejection-free graft survival (95%). The mean serum creatinine level (+/- SD) at 1 year was 1.6 +/- 0.6; at 4 years, 1.6 +/- 0.6. We noted that 8% of recipients had cytomegalovirus (CMV) disease; 4.5%, fractures; 2.8%, cataracts; 1%, posttransplant diabetes; 0.2%, avascular necrosis; 0.2%, posttransplant lymphoproliferative disease; and 0%, polyomavirus. In all, 85% of kidney recipients with functioning grafts remain prednisone-free as of April 1, 2004.As compared with historical controls, the recipients on prednisone-free maintenance immunosuppression had better patient (P = 0.02) and graft survival (P < 0.0001) and lower rates of acute (P = 0.0004) and chronic (P = 0.02) rejection. In addition, they had a significantly lower rate of CMV disease (P < 0.0001), cataracts (P < 0.0001), posttransplant diabetes (P < 0.0001), and avascular necrosis (P = 0.0003). CONCLUSIONS: Prednisone-related side effects can be minimized without maintenance immunosuppression; our prednisone-free recipients do not have increased acute or chronic rejection.  相似文献   
85.
Prednisone-minimization protocols have been successful in low-risk recipients. We report on the use of a protocol incorporating rapid discontinuation of prednisone in a cohort of kidney transplant recipients (n = 79) at increased immunologic risk. Our data suggests that such recipients should not be excluded from prednisone-minimization protocols.  相似文献   
86.
BACKGROUND: Despite improvements in immunosuppressive protocols and patient care, kidney allografts continue to fail. We studied causes of graft loss for primary kidney transplants in the 1990s to determine major causes and potential interventions. METHODS: Causes of graft loss were reviewed for 1467 primary kidney transplants done at our institution between January 1, 1990, and December 31, 1999. Graft loss for that entire population was studied and then the causes of loss selectively examined at <1 year, 1 to 5 years, and>5 years post-transplant. Finally, causes of loss in the 1990s versus the 1980s were compared. RESULTS: Five major causes of graft loss were noted in the 1990s: thrombosis, acute rejection (either alone or combined with delayed graft function or infection), chronic rejection, death with function, and noncompliance. In the first year post-transplant, thrombosis (25%) and death with function (41%) were the major causes of graft loss. After the first year, chronic rejection and death with function predominated. For recipients dying with graft function, cardiovascular disease was the major cause of death. CONCLUSIONS: This study identified the five major causes of kidney graft loss in the 1990s. Different interventions are required to decrease loss from each of these causes. Future research needs to be directed at such interventions.  相似文献   
87.
Upto 35% of infants aged between 6 and 11 months are infected with measles in India with its associated high morbidity and mortality. The objective of the study is to know the waning pattern of placentally transmitted antibodies (PTA) for measles so that the age at which children are likely to become susceptible to measles infection could be identified. A cross-sectional serological survey of children aged 3 to 11 months in one of the Integrated Child Development Service (ICDS) area in Madras city slums was done. Venous blood from 376 children was collected and was tested for Hemagglutination Inhibition (HI) antibodies by standard microtitration technique. Titre greater than or equal to 1:8 has been considered as protective. The proportion of children with immune level and the Geometric Mean Titre (GMT), declined to the least by 5 months which denotes that most of the infants become susceptible to measles infection from as early as 5 months of age. There is no significant difference in the waning pattern between different age groups, sex and nutritional status. A community study for effectiveness of measles vaccine at 6-8 months of age is needed to know the feasibility of immunization earlier than 9 months of age.  相似文献   
88.
Poliomyelitis continues to be one of the crippling diseases affecting children in our country. Seventy four percent of the affected children were under the age of two years. Nearly seventy two per cent of these children were totally unprotected and another 18·4% were partially protected. In 66·6% of the children intramuscular infection served as a provocative factor. Spinal poliomyelitis constituted 72%; the rest were bulbospinal 22·5%, bulbar 3·5%, encephalitic type 2·3% and isolated facial palsy 0·5%. The importance of immunization before the age of one year is stressed.  相似文献   
89.
BACKGROUND: For certain uremic, diabetic patients, a sequential transplant of a kidney (usually from a living donor) followed by a cadaver pancreas has become an attractive option. But how long to wait after the kidney transplant before proceeding with a pancreas transplant is unclear. We studied outcomes in recipients of a pancreas at varying times after a kidney to determine the optimal timing for the second transplant. METHODS: We compared pancreas after kidney (PAK) transplants performed early (< or =4 months) and late (>4 months) after the kidney transplant to determine any significant differences in surgical complications or outcomes between the two groups. RESULTS: Between January 1, 1994, and September 30, 1998, we performed 123 cadaver PAK transplants. Of these, 25 (20%) were early and 98 (80%) were late. Characteristics of the two recipient groups were similar. We found no significant differences in outcome between the two groups. The incidence of surgical complications (bleeding, leaks, thrombosis, infections) and of opportunistic infections (such as cytomegalovirus) did not significantly differ between the two groups. Graft and patient survival rates were also equivalent (P=NS). The incidence of acute rejection by 3 months posttransplant was 20% in both groups. CONCLUSION: The timing of the pancreas transplant for PAK recipients does not seem to influence outcome. As long as an acceptable organ is available and the recipient is clinically stable, a PAK transplant can be performed relatively soon after the kidney transplant.  相似文献   
90.
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