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131.
Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns.  相似文献   
132.
Our goal was to determine the primary stability of overlapping osteochondral grafts used in mosaicplasty by studying the effect of overlapping in an ex vivo model. Osteochondral grafts, 10 mm in diameter, were transplanted from the trochlea of cow femurs to the weight-bearing area of the lateral femoral condyle with 0, 15, or 30% overlap. The grafts were pushed in with a probe at a rate of 2 mm/min, and load (N)-displacement (mm) curves were recorded. In Group I (control, 0% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 572.3 +/- 273.6 and 999.3 +/- 427.6 N, respectively. In Group II (15% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 263.6 +/- 91.7 and 746.6 +/- 88.0 N, respectively. In Group III (30% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 179.4 +/- 31.2 and 657.0 +/- 106.5 N, respectively. The loads that were necessary to produce a 1-mm dent in the grafts were significantly different between Groups I and II and Groups I and III (p < 0.05). These results suggest that stability may be reduced by graft overlapping in mosaicplasty surgery. The results of this ex vivo animal study contribute to a more complete understanding of the primary stability of osteochondral grafts in an overlapping position as well as postoperative protocols.  相似文献   
133.
Maternal serum screening identifies women at an increased risk of a pregnancy with Down's syndrome or trisomy 18 or an open neural tube defect. The triple test, consisting of maternal serum alpha-fetoprotein, unconjugated estriol and human chorionic gonadotropin was carried out by a chemiluminescence immunoassay method in our laboratory. The study consisted of 373 pregnant women. The gestational range for the study group was 14-22 weeks. The mean maternal age for the study group was 28.53 +/- 5.46 years (range 17.4 to 43.5 years); 9.1% of the women were considered at high risk for Down's syndrome based on the test results. In our study the detection rate for Down's syndrome by prenatal karyotyping was 66.6%. Maternal serum screening allows reduction of the number of women requiring amniocentesis without a significant decrease in the detection rate.  相似文献   
134.
Bio-implants in the human body act as passive surfaces that are prone to bacterial adhesion potentially leading to deep body infections. Pedicle screws made of uncoated or silver-coated titanium alloy were used both in vitro and in vivo to determine whether silver-coated materials have antimicrobial properties when they are anodized. Twenty-four New Zealand Albino rabbits were divided into four groups with six in each. In Group 1, the rabbits were exposed to 8 muA direct current (DC) via silver-coated screws. In Group 2, the rabbits were not exposed to any electrical current, but silver-coated screws were used. In Group 3, the rabbits were exposed to 8 muA DC using uncoated screws. In Group 4, the rabbits were not exposed to any electrical current, but uncoated screws were used. Staphylococcus aureus (106 cfu) was inoculated into the rabbits before any electrical current was applied. All the animals were killed, and the areas surrounding the screws were histologically and microbiologically examined. Silver-coated titanium screws prevented implant-associated deep bone infections when they were polarized anodically. The antibacterial effects of the same screws with the same bacterium were confirmed in in vitro experiments on agar plates. When the screws were anodized with the same electrical parameters in vitro, a marked inhibition zone was detected around the silver-coated screws but not around the uncoated screws. Our findings suggest that silver-coated titanium implants can be used to prevent implant-associated deep bone infections when they are polarized anodically.  相似文献   
135.
An anatomical study was conducted to gain orientation regarding the posterolateral approaches. The asterion is defined as the junction of the lambdoid, parietomastoid, and occipitomastoid sutures. This anatomical point has been widely used as a landmark in lateral approaches to posterior fossa. Although there are many common practices in posterolateral approaches, studies providing accurate anatomical knowledge as to what is the correct point to start a craniotomy are limited in number. Therefore, this study was conducted in an attempt to determine the reliability of the asterion for the posterolateral approaches as surgical landmark.  相似文献   
136.
OBJECTIVE: To determine the reliability of medial canthus as a surface landmark to locate supratrochlear vascular pedicle. STUDY DESIGN AND SETTING: The distance from medial canthal line to supratrochlear vascular pedicle was measured in 57 healthy volunteers (Doppler imaging study) and also in 15 fresh cadavers. RESULTS: In the Doppler study, the pedicle was found at most 3 mm lateral or medial to medial canthus (mean +/- SD, 0.8 +/- 0.7 mm). SVP mark tended to be medial to the medial canthus mark in females (males, 6; females, 42), whereas it was lateral to it in males (males, 20; females, 5). In the cadaver study, the pedicle was found 0.7 mm away from medial canthus on average. CONCLUSION: Medial canthus can be used as a reliable landmark for paramedian forehead flaps. When Doppler examination fails, pedicle may be found at most 3 mm away from medial canthus. SVP is more commonly located lateral to medial canthus in males and medial to it in females.  相似文献   
137.
138.
BACKGROUND: Medical treatment is usually ineffective for Holmes' tremor, and surgery is the treatment of choice for many patients. Here we report the case of a 14-year-old girl who developed Holmes' tremor related to a thalamic abscess and was successfully treated with thalamic deep brain stimulation. CASE REPORT: The patient presented with left hemiparesis and headache and was hospitalized. Investigation revealed a thalamic abscess in the left cerebral hemisphere. The abscess was drained via stereotactic surgery and a course of antibiotic treatment was completed. Four months after treatment, the patient developed Holmes' tremor in her left upper extremity. When attempts at medical treatment with levodopa, clonazepam, and trihexyphenidyl all failed, an implant was placed and deep brain stimulation of the ventral intermediate nucleus of the thalamus was initiated. During 2.5 years of follow-up, her tremor diminished by 90%. CONCLUSION: This case demonstrates that medically resistant Holmes' tremor related to a thalamic lesion can be successfully treated with thalamic deep brain stimulation.  相似文献   
139.
OBJECTIVE: Sports-related injuries are among the major causes of testicular trauma. In this study, we aimed to determine sonographically whether chronic urogenital trauma during horse riding increases the prevalence of scrotal sonographic abnormalities. To our knowledge, there are no studies in the literature that have focused on this topic. METHODS: Group 1 included 26 male riders with a mean age +/- SD of 31 +/- 2.9 (range, 26-38) years and with a mean riding experience of 5 +/- 2.6 (range, 1-10) years, whereas group 2 included 26 healthy nonriding men with a mean age of 31 +/- 3.2 (range, 26-41) years. After the clinical evaluation, all patients underwent scrotal sonographic examination. RESULTS: The prevalence of overall scrotal sonographic abnormalities in group 1 was significantly higher than that in group 2 (77% versus 38%; P < .05). The detected sonographic findings in group 1 were varicocele (46%), hydrocele (19%), testicular cyst (4%), epididymal cyst (35%), testicular calcification (19%), epididymal calcification (8%), scrotal calculus (8%), and inhomogeneity of parenchymal echo texture (4%). However, only varicocele (19%), epididymal cyst (19%), testicular calcification (12%), and scrotal calculus (4%) were detected in group 2. Between the 2 groups, the difference was significant for varicocele prevalence (P < .05) and marginally significant for hydrocele prevalence (P = .051). CONCLUSIONS: We recommend scrotal sonographic examination of equestrians when they have a palpable mass or related symptoms, the etiology of which was found in our study to be closely related to horse riding.  相似文献   
140.
Autonomic function is impaired in anemic patients with various etiologies such as vitamin B12 deficiency, sickle cell trait, and thalassemia major. However, there are insufficient data about autonomic functions in patients with iron deficiency anemia, the leading cause for anemia in the general population. In the present study we aimed to investigate the autonomic status in iron deficiency anemia by analyzing the heart rate variability (HRV). Age- and gender-matched 43 patients with iron deficiency anemia and 39 healthy subjects were undertaken into 24-hr Holter monitoring for assessing the HRV. We used serum levels of iron, iron binding capacity, C-reactive protein, vitamin B12, and folate to exclude other causes of anemia. While age, gender, vitamin B12 and folate levels were not different between the groups, HRV values were lower in patients with iron deficiency anemia compared to control group, which reflects parasympathetic withdrawal. Blood hemorheological factors such as decreased viscosity and/or altered red cell deformability may be responsible for this decreased parasympathetic activity. However, these components do not display remarkable contribution in iron deficiency anemia. Therefore, we speculated a probable link between anemia and the accentuated sympathetic activity that may be triggered by hypoxia sensed through carotid bodies. Despite lacking adequate convincing evidence concerning exact mechanism of carotid body activation, it is assumed as due either to hypoxia-related mitochondrial respiratory chain inhibition or potassium channel suppression that leads to intracellular calcium accumulation. In conclusion, the present study demonstrates an altered autonomic balance in patients with true iron deficiency anemia.  相似文献   
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