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991.
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AIM: To review 9 years of annual assessment data in cystic fibrosis (CF) and evaluate the frequency of hepatobiliary abnormalities and the correlation between ultrasound and biochemical findings. MATERIALS AND METHODS: Over a 9-year period (1990-99), 168 children (age range 1-18 years) with CF have undergone an annual assessment which has included clinical, biochemical and ultrasonographic evaluation of the hepatobiliary system. We have retrospectively reviewed the sequential ultrasound reports and correlated them with the contemporaneous biochemical results. RESULTS: A total of 725 ultrasound examinations were performed over the review period. Sixty patients had at least one examination showing an abnormality of liver echo texture and in 39 patients this was a persisting finding. Seven patients (4.2%) developed frank cirrhotic change on ultrasound criteria, while 15 patients (8.9%) had evidence of persistent splenomegaly. Gall-bladder calculi were present in 4.8%. In 176 examinations (24%) there was disparity between the ultrasound findings and aspartate aminotransferase (AST) levels. In 3.0% of cases (five patients) there were persisting abnormalities of liver echo texture and persisting splenomegaly with a normal range AST value. CONCLUSION: No perfect method of assessing hepatobiliary involvement in CF is currently available. Ultrasonographic and biochemical assessment may reflect different aspects of disease progression. Routine use of ultrasound in annual assessment allows identification of a minority of patients with liver changes but with normal biochemistry.  相似文献   
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Individuals undergoing an unaccustomed exercise bout incorporating a high degree of eccentric muscle contractions commonly experience delayed onset muscle soreness. The damage manifests itself via tenderness, loss of strength, swelling, elevated muscle enzyme activity and loss of flexibility. Following an initial "damage bout," a repeated bout results in reduced symptoms. This protective effect is known as the repeated bout effect (RBE) and can last up to 24 weeks between bouts. The mechanism for this RBE is unclear and both central and local mechanisms have been suggested. In an attempt to test the central hypothesis, 12 subjects (mean age = 22.5± 4yrs, ht = 167±9cm, mass = 71.5±13.5kg) underwent an exercise protocol whereby one leg was exercised eccentrically and following complete recovery; the contralateral leg was exercised in the same manner. Subjects were required to step on and off a 46-cm step for 20 minutes at a cadence of 15 steps/minute. One leg was used to go up the step (concentric) while the opposite was used to go down (eccentric). Approximately two weeks later and following complete recovery, the protocol was repeated with the concentrically exercise leg now performing the eccentric contraction. Data analyses indicate that muscle damage was induced during both trials on the eccentrically exercised leg as evidenced by a change in tenderness (bout 1 P < 0.05: bout 2 P < 0.01), pain scores (bout 1 P < 0.0001; bout 2 P < 0.01), and strength loss (bout 1 P = 0.001; bout 2 P = 0.001) over the four day follow up period. No tenderness was evident on the concentrically exercised limbs when compared to baseline (Bout 1: P =0.13, Bout 2: P = .06). Pain was significantly lower in bout two versus bout one (P< 0.04), however, we attribute this to a tolerance effect. Neither strength loss nor tenderness were significantly different between bouts. In the current study, damage was induced in both bouts in the eccentrically exercised limbs. This preliminary data does not provide evidence for a central mechanism in that an initial bout of eccentric exercise using one limb did not provide protection against damage from a repeated bout with the contralateral limb two weeks later.Key words: Eccentric, exercise, muscle damage, protection, contralateral  相似文献   
997.
OBJECTIVE: The purpose of this study was to determine the predictive ability of parameters of 24-hour ambulatory blood pressure monitoring for the development of preeclampsia or gestational hypertension in women who are already considered at risk for these disorders. STUDY DESIGN: One hundred twenty-two pregnant women who were considered high risk for the development of preeclampsia underwent 24-hour ambulatory blood pressure monitoring between 18 and 30 weeks gestation, while their condition was normotensive according to routine mercury sphygmomanometry. One hundred sixty-four healthy primigravid women who were considered at usual risk for preeclampsia underwent the same tests as a parallel study. Routine blood pressure, awake and sleep average blood pressure, and 24-hour mean average blood pressure were entered into multiple logistic regression as predictors of either preeclampsia or gestational hypertension; significant variables were then tested by a series of receiver operator curves. RESULTS: Eight percent of usual risk and 45% of high risk women experienced the development of preeclampsia or gestational hypertension. In both groups, the average routine mercury blood pressure and awake, sleeping, and 24-hour ambulatory blood pressure monitoring-derived blood pressure were significantly higher in women who later experienced the development of preeclampsia or gestational hypertension. In usual risk women, 24-hour systolic blood pressure of >or=115 mm Hg and sleeping systolic blood pressure of >or=106 mm Hg were predictive of later preeclampsia or gestational hypertension, but sensitivities were low (77% and 54%, respectively). In high risk women, sleeping diastolic blood pressure of >or=62 mm Hg and sleeping mean arterial pressure of >or=79 mm Hg were predictive of preeclampsia or gestational hypertension, but again sensitivities were low (70% and 65%, respectively). CONCLUSION: Awake and sleeping blood pressure are higher in midpregnancy in women who later experience the development of preeclampsia or gestational hypertension. Twenty-four-hour ambulatory blood pressure monitoring provides a noninvasive method of selecting some of these women, but this test has a sensitivity no better than that of other predictive tests, even in women at high risk for preeclampsia.  相似文献   
998.
BACKGROUND: This article describes the use of focus groups in research, including the advantages and disadvantages of using this type of research methodology. Using an example of a focus group of patients who experienced chronic pain, the authors discuss the planning, organisation, conduct and analysis of focus groups. CONCLUSION: Focus groups enabled an exploration of the topics in-depth including obtaining insight from a patient's perspective of the management of their chronic pain. It was important and of value to take into account the experiences and expectations of health service delivery from a consumer's perspective.  相似文献   
999.
BACKGROUND: No consensus exists on the amount of tension that should be applied to anterior cruciate ligament grafts to best facilitate graft incorporation and re-create normal knee mechanics. HYPOTHESIS: Differences in initial graft tension will affect postoperative knee stability. STUDY DESIGN: Prospective, randomized, double-blind clinical trial. METHODS: Forty-nine patients undergoing bone-patellar tendon-bone autograft anterior cruciate ligament reconstruction by a single surgeon were randomized into high-tension (n = 27) and low-tension (n = 22) groups. Grafts were set at 90 N or 45 N. Arthrometric measurements (KT-1000 arthrometer manual maximum) of anterior tibial displacement and knee range of motion were made before surgery and at 1 week and an average of 20 months after surgery. Knee outcome scores were collected before and after surgery, and a single-leg hop test was also performed at final follow-up. RESULTS: After anterior cruciate ligament reconstruction, anterior tibial displacement was significantly greater in the patients in the low-tension group (P < .05). The side-to-side difference in anterior tibial displacement in the high-tension and low-tension groups was 1.1 +/- 1.7 mm versus 2.4 +/- 2.4 mm 1 week after surgery and 2.2 +/- 1.6 mm versus 3.0 +/- 2.2 mm at follow-up. Five patients had abnormal anterior tibial displacement (>5 mm side-to-side difference), and all were in the low-tension group (P <.05). Knee outcome scores improved with surgery (P <.01), with similar results for low-tension and high-tension groups. Hop test deficits were not different between groups. CONCLUSIONS: Initial graft tension affects the restoration of knee stability. A graft tension of 45 N was not sufficient for restoring knee stability.  相似文献   
1000.
BACKGROUND: This study aimed to determine the reasons for dentists' choice of materials, in particular amalgam and resin composite, in Australia. METHOD: A questionnaire was developed to elicit this information. The names and addresses of 1000 dentists in Australia were selected at random. The questionnaire was mailed to these dentists with an explanatory letter and reply-paid envelope. RESULTS: A total of 560 replies were received. Regarding choice of material, 99 per cent of respondents cited clinical indication as an influencing factor, although patients' aesthetic demands (99 per cent of respondents), patients' wish (96 per cent), patients' financial situation (82 per cent), and lecturers' suggestions (72 per cent) were also reported to influence respondents' choice of materials. Twelve per cent of respondents used composite 'always', 29 per cent 'often', 32 per cent 'sometimes', 23 per cent 'seldom' and 4 per cent 'never' in extensive load-bearing cavities in molar teeth. For composite restorations in posterior teeth, 84 per cent 'always', 'often' or 'sometimes' used the total etch technique, 84 per cent used a thick glass-ionomer layer and 36 per cent never used rubber dam. Fifty-nine per cent of respondents reported a decreased use of amalgam over the previous five years. Sixty-eight per cent of respondents agreed with the statement 'discontinuation of amalgam restricts a dentist's ability to adequately treat patients'. Seventy-five per cent considered that the growth in the use of composites increased the total cost of oral health care. CONCLUSIONS: Of the respondents from Australia 73 per cent place large composite restorations in molar teeth and their choice of material is influenced greatly by clinical indications, and patients' aesthetic demands.  相似文献   
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