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71.
This prospective study compared images obtained with a photostimulable imaging plate with matched images obtained with a conventional screen-film combination in 26 patients undergoing intraoperative arteriography. Diagnostic accuracy of the two techniques was assessed objectively, and image quality was assessed subjectively. In 16 patients (62%), the radiation exposure was reduced by 50% for the imaging plate technique by decreasing the mAs level generally used for the screen-film combination. Because of the dynamic range of the imaging plate system, no repeat examinations were necessary, while 12% of the screen-film studies had to be repeated because of over- or under-penetration. Imaging plate studies required 6% more time for processing than screen-film studies. Receiver-operating-characteristic analysis indicated no difference in diagnostic accuracy between the two imaging techniques. Subjective evaluation also revealed no difference in observer preference for imaging plate or screen-film studies. The imaging plate technique is an excellent alternative to screen-film studies in the operating room.  相似文献   
72.
73.
T-lymphocyte subsets and human T-cell lymphotropic virus type III antibody prevalence were studied in African patients with the acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC), and in female prostitutes. African blood donors and healthy Zairian and Rwandese persons matched for age, sex, and annual income served as controls. Seropositivity was noted in 46 (87%) of 53 patients with AIDS, 29 (88%) of 33 patients with ARC, 67 (80%) of 84 prostitutes, and five (12.5%) of 40 and eight (15.5%) of 51 healthy controls and blood donors, respectively. Patients with AIDS and ARC had a significantly lower OKT4/OKT8 ratio than healthy African controls. These studies suggest that human T-cell lymphotropic virus type III infection has already spread extensively into the general African population and that female prostitutes could be an important human reservoir of AIDS virus in the heterosexual population.  相似文献   
74.
Autonomic response to auditory stimulation   总被引:2,自引:0,他引:2  
Autonomic and behavioral response to fear stimulation (sudden noise 80 dB) was studied in 12 sleeping infants at ages 8–50 weeks. The aim of the present study was to identify a possible passive defense response in infants. The response, which is widespread in birds and mammals, is characterized by apnea and bradycardia with circulatory changes as seen during the forced diving response. Upon stimulation, two respiratory responses were elicited: apnea preceded by irregular respiration or simple irregular respiration. Apnea was elicited in 58% of stimulations at ages 8–16 weeks compared to 14% at 28–50 weeks. The mean duration of apnea decreased from 7.8 s(± 1.8 s) at 8–13 weeks to 4.7s (± 1.1s) at 17–20 weeks. The preceding irregular respiration increased from 5.3 s (± 4.4 s) to 10.6 s (± 5.4 s) at the same ages. The heart rate response was biphasic and were interpreted as the orienting response. The mean deceleration in relation to apnea was 16% at 8–16 weeks and was reduced to 8% at 28–50 weeks. Infants of smoking mothers were more prone to respond with apnea than infants of nonsmoking mothers (73% versus 38%). REM sleep and long postprandial sleep time increased the probability of apnea response (62% versus 38% and 66% versus 35%). The responses seen may be interpreted as expressions of the passive defense response.  相似文献   
75.
Introduction: Vertical deviations in thyroid eye disease (TED) can present a surgical challenge due to the difficulty and unpredictability of surgery and the high risk of postoperative drift towards overcorrection. This study reports the postoperative outcomes of patients who underwent adjustable vertical strabismus surgery with Vicryl sutures for thyroid eye disease. Methods: We reviewed the records of patients seen for vertical TED strabismus surgery from January 2005 through December 2009. Clinical details were recorded preoperatively, post-adjustment, and at 3 weeks, 3 months, and 1 year postoperatively. Results: The study included 42 patients. Mean age was 62.4 years and 70% were female. All patients were diplopic preoperatively. The mean near vertical deviation was 21.1 prism diopters (PD) preoperatively, 4.0 PD at 3 weeks postoperatively, 5.0 PD at 3 months, and 4.4 PD at 1 year (all mean results representing undercorrection). 71.4% were free of diplopia postoperatively. Seven patients required further surgery, 2 patients needed further botulinum toxin A. Eight patients experienced an overcorrection; five at 3 weeks, seven at 3 months, and eight at 1 year. There was a significant difference in the mean near angle at tie-off post-adjustment in the patients that overcorrected compared to those that did not reverse (3.1 PD vs 7.1 PD; P=0.005). Discussion: Adjustable surgery for vertical strabismus in thyroid eye disease may result in late overcorrection and the need for further intervention. We propose that aiming for an immediate post-adjustment angle of 8 PD undercorrection for near would allow for postoperative drift and reduce the chances of a late overcorrection. This would require careful preoperative counseling of the patient in order to explain that immediate undercorrection and persistent diplopia were necessary in order to generate a better long-term result.  相似文献   
76.
BACKGROUND: Allergic reaction is characterized by a complex inflammatory process. Some of the new antihistamines have antiallergic effects and can affect the inflammatory cell recruitment via adhesion molecule downregulation. We aimed to assess in a 12-month study whether continuous treatment with an antihistamine (terfenadine) can reduce respiratory symptoms and local inflammation in children with mite allergy. METHODS: The study was double-blind and placebo-controlled: it involved two parallel groups of children suffering from rhinoconjunctivitis and/or mild intermittent asthma due to mite allergy. They received either terfenadine (1 mg/kg per body weight per day) or placebo for 1 year. Nasal, conjunctival, and bronchial symptoms were recorded by diary cards; at each of the programmed control visits, a nasal scraping for inflammatory cells and ICAM-1 was performed. Some additional clinical parameters were also recorded: days of school absence, extra visits for acute respiratory symptoms, and days of hospital admission. RESULTS: Only children treated with terfenadine achieved significant control of symptoms (P<0.05 in 8 out of 12 months) and allergic inflammation, as shown by inflammatory cell infiltrate and ICAM-1 expression at nasal level (P<0.001), and had significantly fewer extra visits and school absences than the placebo group (P<0.03). No side-effects were reported in either group. CONCLUSIONS: The present study demonstrates that continuous terfenadine treatment (1 mg/kg body weight per day) could decrease respiratory symptoms and allergic inflammation, and it had an additional antiallergic effect in reducing ICAM-1 expression on nasal epithelial cells. Therefore, the present results confirm the efficacy of a long-term therapeutic strategy in controlling allergic inflammation.  相似文献   
77.
Absence of the palmaris longus muscle: a population study.   总被引:4,自引:0,他引:4       下载免费PDF全文
We examined 300 Caucasian subjects (150 males, 150 females) aged 18-40 years to assess the incidence of palmaris longus absence. The presence or absence of palmaris longus was assessed by clinical inspection. Forty-nine subjects had unilateral absence of palmaris longus (16%). The tendon was absent bilaterally in 26 subjects (9%). Unilateral and bilateral absence was more common in males, however this was not statistically significant (p = 0.25 and 0.56 respectively). In those subjects with unilateral absence, the right side was found to be more commonly affected however no statistical significance was evident (p = 0.25).  相似文献   
78.
The development of effective vaccines against difficult disease targets will require the identification of new subunit vaccination strategies that can induce and maintain effective immune responses in humans. Here we report on a phase 1a clinical trial using the AMA1 antigen from the blood-stage Plasmodium falciparum malaria parasite delivered either as recombinant protein formulated with Alhydrogel adjuvant with and without CPG 7909, or using recombinant vectored vaccines—chimpanzee adenovirus ChAd63 and the orthopoxvirus MVA. A variety of promising “mixed-modality” regimens were tested. All volunteers were primed with ChAd63, and then subsequently boosted with MVA and/or protein-in-adjuvant using either an 8- or 16-week prime-boost interval. We report on the safety of these regimens, as well as the T cell, B cell, and serum antibody responses. Notably, IgG antibody responses primed by ChAd63 were comparably boosted by AMA1 protein vaccine, irrespective of whether CPG 7909 was included in the Alhydrogel adjuvant. The ability to improve the potency of a relatively weak aluminium-based adjuvant in humans, by previously priming with an adenoviral vaccine vector encoding the same antigen, thus offers a novel vaccination strategy for difficult or neglected disease targets when access to more potent adjuvants is not possible.  相似文献   
79.
Autologous bone marrow transplants (BMTs) can repopulate the hematologic system of patients treated with marrow-ablative chemotherapy and/or radiotherapy. However, treatment of the bone marrow graft to eliminate residual tumor cells prior to reinfusion can delay the return of peripheral blood elements, presumably from damage to or loss of hematopoietic stem cells responsible for hematologic recovery. To develop a model predictive of hematologic recovery, we studied the progenitor cell contents of 4-hydroperoxycyclophosphamide (100 micrograms/mL)-purged bone marrow grafts of 40 consecutive patients undergoing autologous BMT at this center. Granulocyte-macrophage colonies (CFU-GM) were grown from all grafts after treatment with this chemotherapeutic agent, but erythroid (BFU-E) and mixed (CFU-GEMM) colonies were grown from only 44% and 33% of the grafts respectively. The recovery of CFU-GM after purging ranged from 0.07% to 23%. The logarithm of CFU-GM content of the treated grafts was linearly correlated with the time to recovery of peripheral blood leukocytes (r = -0.80), neutrophils (r = -0.79), reticulocytes (r = -0.60), and platelets (r = -0.66). The CFU-GM content of purged autologous bone marrow grafts may reflect the hematopoietic stem cell content of the grafts and thus predict the rate of hematologic recovery in patients undergoing autologous BMT.  相似文献   
80.
We examined the effects of varying incubation conditions on the in vitro activity of 4-hydroperoxycyclophosphamide (4HC). 4HC activity against CFU-GM and against the K562 tumor cell line decreased with increasing the RBC concentration of the incubation mixture. Increasing the concentration of nucleated bone marrow cells in the incubation mixture also decreased the 4HC activity. Evaluation of 53 consecutive patients undergoing autologous bone marrow transplantation (BMT) revealed that the incubation RBC concentration during clinical purging showed a similar effect on CFU-GM recovery. Aldehyde dehydrogenase content of RBCs and nucleated marrow cells appears to be the cause of the inhibition of 4HC activity. Although there was no difference in individual CFU-GM sensitivity to 4HC among normals, previously treated patients undergoing autologous BMT showed significant variability in CFU-GM sensitivity to 4HC. The combined effects of incubation RBC concentration and individual patient 4HC sensitivity appear to account for most of the variability in CFU-GM recovery and speed of hematologic recovery after clinical purging with 4HC.  相似文献   
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