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21.
The aim of this study was to evaluate the clinical outcome of freeze-dried compared to fresh frozen allograft tissue used as a substitute for a ruptured ACL of the knee. In addition, the incidence of any graft rejection phenomena was recorded. Forty-one patients with ACL deficient knees underwent reconstructive surgery using a patellar bone-tendon-bone allograft that had been freeze-dried (Group 1, N = 14) or fresh frozen (Group 2, N = 27). All patients underwent the same implant technique and rehabilitation program. Followup ranged from 24 to 36 months. The evaluation consisted of subjective, objective, and instrumented laxity testing (KT-1000, MEDmetric, San Diego, CA; and Genucom, FARO Medical Technologies, Inc., Montreal, Canada). There were 31 males and 10 females. Eleven (79%) patients in Group 1 thought their knee was "normal" or "improved," and 25 (93%) in Group 2 thought the same. In addition, 10 (71%) patients in Group 1 denied any "giving way," compared to 26 (96%) in Group 2. The mean Lysholm knee score in Group 1 was 86/100 (range, 22 to 100) compared to 92/100 (range, 59 to 100). Clinical examination included the Lachman test and tests for anterior drawer sign and pivot shift. Postoperatively, Group 1 patients had the following results: Lachman test--seven Grade 0, six Grade 1, one Grade 2; anterior drawer sign--eight Grade 0, five Grade 1, one Grade 2; and pivot shift--seven Grade 0, five "trace," and two "present."(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Keypecking by seven pigeons, maintained by a fixed-ratio 30 schedule of food presentation, was decreased in rate by acute pre-session administration of cocaine. In Part 1 (four pigeons), tolerance to the rate-suppressing effects of cocaine developed during daily administration conditions. Tolerance persisted (1) when daily cocaine injections were replaced by conditions in which cocaine was administered every other day, then every fourth day, then every eighth day, then every 16th day, with all intervening sessions preceded by saline injections and (2) when daily cocaine administration was replaced abruptly by a condition in which cocaine injections were spaced 16 days apart, with all intervening sessions preceded by saline. In Part 2 (three pigeons), tolerance developed during intermittent administration conditions (e.g. cocaine injected every eighth day) for two subjects, and during daily administration for the third subject. As in Part 1, tolerance persisted when cocaine was administered only once every 16 days. These results are consistent with an interpretation of tolerance based upon operant compensatory reactions to drug-induced behavioral disruptions and suggest that a simple associationist model of tolerance to cocaine-induced response-rate suppression may be inadequate. The data also have practical implications regarding tolerance development during intermittent administration conditions similar to conventional acute dose-effect determination procedures.  相似文献   
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PURPOSE: African Americans have a higher incidence of hypertension than other racial groups. Furthermore, some research suggests that normotensive individuals who exhibit exaggerated blood pressure (BP) responses to exercise may be at risk for future hypertension. This study sought to determine whether normotensive African Americans exhibited exaggerated BP responses to static exercise or dynamic exercise relative to Caucasian Americans and Asian Americans. METHODS: Thirty normotensive subjects participated from each of the three racial groups (15 men and 15 women). Subjects held 30% of maximal voluntary contraction (right knee extension) for 3 min, and BP was recorded during the 3rd min. On a separate occasion, subjects cycled for six min at a power equivalent to 70% of VO2 reserve, and BP was recorded during the 6th min. RESULTS: Static exercise produced large, significant increases in both systolic and diastolic BP (35 +/- 1.5 and 29 +/- 1.3 mm Hg, respectively). Dynamic exercise produced large, significant increases in systolic BP (51 +/- 1.6 mm Hg) and moderate, yet significant, increases in diastolic BP (8 +/- 1.0 mm Hg). There were no significant differences between racial groups in BP response to either static exercise or dynamic exercise. However, during dynamic exercise, men had a higher systolic BP response than did women. CONCLUSIONS: African Americans who are normotensive at rest do not exhibit a greater BP response to static exercise or dynamic exercise than do Caucasian Americans or Asian Americans.  相似文献   
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BACKGROUND: Therapeutic ineffectiveness and noncompliance with antipsychotic agents are major contributors to rehospitalization in patients with psychotic disorders. It is unknown whether risperidone's favorable side effect profile compared with that of the conventional antipsychotics results in improved compliance and reduced hospitalizations in a naturalistic setting. The purpose of this study was to test the hypothesis that treatment with risperidone reduces readmission rates and associated costs when compared with treatment with perphenazine or haloperidol. METHOD: Inpatients prescribed either risperidone, perphenazine, or haloperidol between January 1, 1995, and December 31, 1995, as a single oral antipsychotic at discharge were retrospectively identified. Data were collected for that index hospitalization and for a 1-year follow-up period. Primary outcome measures included re-admission rates, changes in antipsychotic therapy, anticholinergic drug use, and costs. RESULTS: There were 202 evaluable patients (81 treated with risperidone, 78 with perphenazine, and 43 with haloperidol). Baseline demographics were similar between groups except that more patients in the risperidone group had a primary diagnosis of psychotic disorder or had been hospitalized in the year prior to study. The percentage of patients readmitted during the 1-year follow-up period was similar among drug groups (41% risperidone, 26% perphenazine, and 35% haloperidol) when controlled for baseline differences in diagnosis and hospitalization history (p = .32). Anticholinergic drug use was more common in the haloperidol group (p = .004). Mean yearly cost (drug + hospitalization) in the risperidone group was $20,317, nearly double that in the other treatment groups (p < .001). CONCLUSION: The results from this naturalistic study indicate that the high cost of risperidone is not offset by a reduction in readmission rates when compared with conventional antipsychotics.  相似文献   
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In a simulated field trial Bacillus thuringiensis var israelensis (BTI) pellet formulation exhibited an enhanced efficacy with increasing dose. A dosage of 1.0 and 1.5 ppm was most effective under simulated field conditions. In field trials persistence of BTI pellet (1.0 ppm) was observed for 35 days in moderately polluted water collection as compared to 21 days in highly polluted water bodies.KEY WORDS: Bacillus thuringiensis, Malaria, Mosquito control  相似文献   
28.
OBJECTIVE: We attempted to compare the use of low-dose heparin with a standard dose of 40 mg prednisone daily (both plus low-dose aspirin) for treatment of pregnant women with antiphospholipid antibody-associated recurrent fetal loss with respect to maternal and perinatal morbidity and efficacy in prevention of fetal death. STUDY DESIGN: A multicenter randomized trial included 20 patients. Generalizability of results from randomized patients was evaluated by means of additional data from 13 women refusing and 12 women ineligible for randomization. Data from study groups were compared with Fisher's exact test, and generalizability was evaluated with a chi 2 test for trend. RESULTS: Live birth rates were the same (75%) with either treatment, but "serious" maternal morbidity and the frequency of preterm delivery were significantly higher among women randomly assigned to prednisone (p = 0.02 vs p = 0.006). Preterm delivery among prednisone-treated women was usually associated with premature rupture of the membranes or preeclampsia. These results could be generalized to the other groups of women ascertained during the course of the study. CONCLUSIONS: Low-dose heparin should be preferred to prednisone when treatment is indicated for high-risk pregnant women with antiphospholipid antibodies.  相似文献   
29.
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration /= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children.  相似文献   
30.
Hypospadias trends in two US surveillance systems   总被引:6,自引:0,他引:6  
OBJECTIVE: Hypospadias is a common congenital anomaly, the cause of which is unknown. Unexplained increases in the rates of hypospadias occurred in five European countries in the 1970s and 1980s. We examined data from two birth defects surveillance systems in the United States for evidence of similar trends. METHODOLOGY: The Metropolitan Atlanta Congenital Defects Program (MACDP) provided birth prevalence rates from 1968 to 1993. The nationwide Birth Defects Monitoring Program (BDMP) provided rates from 1970 to 1993. MACDP data are population-based and could be categorized by the severity of the hypospadias. BDMP data allowed analysis of rate trends for the four census regions of the United States. RESULTS: Data from both surveillance systems showed an approximate doubling of hypospadias rates in the 1970s and 1980s. MACDP data showed that the rate of severe cases increased while the ratio of mild to severe cases decreased. BDMP data showed that hypospadias rates increased markedly in all four regions of the United States. CONCLUSIONS: The observed increases are unlikely to be attributable to increased sensitivity of the surveillance systems or the identification of more mild cases by physicians over time, because either trend would have increased rather than decreased the ratio of mild to severe cases. If real, these trends represent the largest number of cases and the first report of an increase in hypospadias rates outside of Europe. Additional investigation of a possible increase in hypospadias rates is warranted.  相似文献   
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