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91.
OBJECTIVES: To examine trends in rates of firearm related deaths in Victoria, Australia, over 22 years in the context of legislative reform and describe and investigate impact measures to explain trends. DESIGN: Mortality data were extracted from vital statistics for 1979-2000. Data on firearm related deaths that were unintentional deaths, assaults, suicides, and of undetermined intent were analyzed. Rates were calculated with population data derived from estimates by the Australian Bureau of Statistics. A quasi-experimental design that used a Poisson regression model was adopted to compare relative rates of firearm related deaths for Victoria and the rest of Australia over three critical periods of legislative reform. The Wilcoxon signed ranks test was used to assess changes in the types of firearm related deaths before and after 1998. RESULTS: In Victoria, two periods of legislative reform related to firearms followed mass shooting events in 1988 and 1996. A national firearm amnesty and buyback scheme followed the latter. Victorian and Australian rates of firearm related deaths before reforms (1979-86) were steady. After initial Victorian reforms, a significant downward trend was seen for numbers of all firearm related deaths between 1988 and 1995 (17.3% in Victoria compared with the rest of Australia, p<0.0001). A further significant decline between 1997 and 2000 followed the later reforms. After the later all state legislation, similar strong declines occurred in the rest of Australia from 1997 (14.0% reduction compared with Victoria, p = 0.0372). Victorian reductions were observed in frequencies of firearm related suicides, assaults, and unintentional deaths before and after the 1988 reforms, but statistical significance was reached only for suicide. CONCLUSION: Dramatic reductions in overall firearm related deaths and particularly suicides by firearms were achieved in the context of the implementation of strong regulatory reform.  相似文献   
92.
Among 318 cases of non-Hodgkin's lymphoma (NHL) treated in our unit, 145 (45.6%) had primary extranodal NHL (PE-NHL). The stomach was the most common site (42.1 %), followed by the PE-NHL of the head and neck region. Histologically aggressive histologies (65.5% intermediate and 20.7% high grade) predominated. 89.6% of the cases were localized (stage Ie, 51% and stage II, 38.6%) but 28% had B symptoms. CR was achieved in 82.1 % of the cases. 5-years disease free survival and overall survival were both 65%. Factors that influence prognosis were stage and high grade histology. Among various primary sites the Waldeyer's ring, small intestine and testes had the worse prognosis. Compared to nodal NHL, the PE-NHL were more frequently localized, belonged more often to aggressive histologies and had more often distal extranodal relapses. CR rates and disease free and overall survival were significantly better for PE-NHL. The survival rates, however, listed according to stage and histology for nodal and PE-NHL were not different.

We conclude that although PE-NHL differed from nodal NHL in several respects, prognosis is mainly a factor of stage and histology rather than of the primary localization per se.  相似文献   
93.
94.
For the last 50 years, high-energy electron beams have been used mainly for treatment of superficial targets. Accordingly, two-dimensional (2D) measurements are required to determine the margin between the surface and protected normal tissues in high-dose-gradient regions. As recommended by the AAPM, 2D electron beam dosimetry should be conducted primarily with films because of their high spatial resolution and because of the fact that they produce permanent records. In this work, the dosimetric characteristics of a newly developed radiochromic film, GAFCHROMIC EBT film were used to study treatment parameters for therapeutic electron beams. The dose-response curve was found to be weakly dependent on the electron beam energy (within +/-4%). The effect of fractionation, as well as electron beam dose rate, had small influence on the calibration curve of EBT films (+/-2.5% and 2%, respectively). For the investigated range of depth, dose-response curves are nearly independent of the calibration depth. As for the cone size dependence, we found that it is accurate to calibrate GAFCHROMIC EBT films using a 10 x 10 cm(2) cone and apply this calibration to other cone sizes.  相似文献   
95.
OBJECTIVE: To quantify and describe medically treated sport and active recreation injuries in a defined region of the Latrobe Valley from 7 November 1994 to 6 November 1995. METHOD: A geographic target area was defined, restricted to the six postcodes that fell wholly within the catchment area of the Latrobe Regional Hospital. Data describing medically treated sport and active recreation injuries to Latrobe Valley residents aged over 4 years (about 70,000) were selected by postcode from three sources: the Victorian Admitted Episodes Dataset (hospital admissions), the Victorian Injury Surveillance System (presentations to hospital emergency departments), and the Extended Latrobe Valley Injury Surveillance (ELVIS) project (presentations to general practitioners). RESULTS: At least 2300 cases of medically treated sport and active recreation injury were recorded. This corresponds to a hospital admission rate of 16/10,000 population, emergency department presentation rate of 169/10,000 population, and a general practitioner presentation rate of 187/10,000 population. There were more male patients than female, and younger age groups were also overrepresented, but these data may reflect the greater participation of these groups in sport and active recreation. Australian football was associated with the highest number of injuries (accounting for 24.0% and 22.0% of presentations to emergency departments and general practitioners respectively) followed by cycling (15.7% and 12.6%) and basketball (17.5% and 13.5%). CONCLUSIONS: This study shows that routine health sector data collections in defined populations can provide useful information on the size, distribution, and characteristics of the problem of sport and active recreation injuries at the community level. However, all current health sector systems for injury data collection and surveillance require attention to improve case capture and identification and data quality.  相似文献   
96.
AIM: Hemodialysis for patients bleeding or at risk for bleeding requires special modalities of treatment that are difficult to perform without potential side effects. A simple, safe and adequate method may be applied. METHODS: A modified way of extracorporeal circuit preparation, which focuses on minimizing the blood-air interface and negligible saline flushing of 50 ml/h, is applied for a maximum of 3-hour session with routine (not one-to-one) nursing attendance. Data from 16,954 sessions performed with patients bleeding or at risk for bleeding (15,730 retrospectively and 1,224 prospectively collected) were analyzed. RESULTS: Cumulative failure of treatment, as defined by clotting of the extracorporeal circuit requiring termination of the procedure or replacement of the clotted part, was not more than 5% as expected for anticoagulation-free hemodialysis. For the prospectively recorded sessions, blood flow was 234 +/- 30 ml/min with less than 250 ml/min in 42.4% of the sessions. Native blood access was used in 426 (34.8%), double-lumen catheter in 798 (65.2%), 42 were isolated ultrafiltration sessions and 64 blood, 21 plasma, 9 platelet units were transfused. Post/pre urea ratio was 0.50 +/- 0.12. Logistic regression showed that among the following: duration of the session, type of dialysis, ultrafiltration rate, hematocrit, number of platelets, serum total protein, transfusions, blood flow and type of access, only blood flow significantly affected failure incidence (coefficient B = -0.041, exp(B) = 0.96, p = 0.04). No complications due to treatment were noted. CONCLUSION: In patients with active, or at risk for, bleeding, hemodialysis without systemic anticoagulation can be adequately and safely performed almost as a routine session.  相似文献   
97.
To evaluate the prevalence of hepatitis C virus (HCV) infection in Greek renal transplant (RT) patients and its association with abnormal liver function tests (LFTs), serum anti-HCV was determined (Ortho-ELISA test system) in 206 RT and 245 haemodialysis patients (HD) as controls. The prevalence (10.2%) of anti-HCV in RT patients was significantly higher (P < 0.0001) than in the Greek general population (0.7%) and lower (P < 0.0001) than in the HD patients (23.8%), and was not related to the patients' age, post-transplant time or pre-transplant HD time. None of the anti-HCV RT patients was HBsAg +, whereas 13 (62%) and 12 (57%) of them were anti-HBsAg + and anti-HBc +, respectively. The incidence of abnormal LFTs in anti-HCV + HBsAg ? and anti-HCV ? HBsAg + RT patients was similar. Our findings indicate that: (a) the prevalence of serum anti-HCV in the Greek RT population is high, although considerably lower than in HD pts; (b) anti-HCV + RT patients have a high incidence of abnormal LFTs, comparable to that seen in HBsAg + RT patients; and (c) in a substantial proportion of anti-HCV + RT patients there is evidence of previous HBV infection.  相似文献   
98.
OBJECTIVE: To describe the motorcycle fleet and rider characteristics on Victorian farms. DESIGN: Cross-sectional postal survey. SETTING: Victorian agricultural industries. PARTICIPANTS: A total of 1382 randomly selected farmers in 2001. MAIN OUTCOME MEASURES: Farm motorcycle characteristics, use and maintenance schedule; motorcycle rider characteristics, respondent demographics and property characteristics. RESULTS: A total of 70% of farms had motorcycles, with an average of 1.7 per property. A total of 49% were four-wheel, and 44% were two-wheel. The average engine size and age were 255 cc and 8.8 years, respectively. The milk cattle sector owned the largest share of the motorcycle fleet and cereal/grain farms the smallest share. Four-wheel motorcycles were often used across the entire spectrum of agricultural tasks. Two-wheel motorcycle use was concentrated more on mustering and transport. A total of 61% of farms performed motorcycle maintenance every 1-6 months. Fifteen per cent of riders were under 15 years of age, and the majority (71%) rode four-wheel motorcycles. A total of 29% of all riders had received some form of motorcycle training. CONCLUSIONS: This study provides useful information on state-level patterns of farm motorcycle use, as well as the key safety behaviours of rider training and motorcycle maintenance. This information might serve as baseline data for future monitoring and surveillance, and might assist with planning of prevention programs.  相似文献   
99.
100.
Plasma fibronectin was determined in 121 normal adults and in 149 patients. Fibronectin levels in normals were strongly influenced by sex and age. The mean value of the protein in cancer patients did not differ from that in normal controls; however, patients with cryofibrinogenaemia or extensive liver metastases had lower values whereas those with obstructive jaundice due to pancreatic carcinoma had higher values than normal controls. Fibronectin levels were greatly increased in patients with primary biliary cirrhosis and moderately elevated in nephrotic syndrome. In patients with severe infection or sepsis, plasma fibronectin did not show a consistent pattern. Patients with overt disseminated intravascular coagulation, irrespective of its cause, had the lowest plasma fibronectin concentrations.  相似文献   
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