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61.
BACKGROUND: Renal insufficiency is characterized by lipoprotein abnormalities including elevated triglyceride levels. PATIENTS AND METHODS: The safety and efficacy of micronized fenofibrate as a treatment for dyslipidemia in patients with progressive renal insufficiency was evaluated in a randomized, placebo-controlled double-blind study comparing fenofibrate and dietary modification to dietary modification alone. Patients were evaluated following a 3-month pre-randomization period of dietary counseling. Twenty-eight patients with moderate renal insufficiency and triglyceride levels 2.3 mmol/l or LDL/HDL ratio 5 were randomized to placebo (n = 12) or fenofibrate (n = 16) therapy. Treatment and dietary counseling continued for 6 months. RESULTS: Ten of 16 patients (63%) treated with fenofibrate achieved a 30% reduction in triglyceride levels or LDL/HDL ratio reduction < 5 compared to 2 of 17% in the placebo group (p = 0.015). Triglyceride levels were significantly reduced in the fenofibrate group (-31%) versus placebo (+1.3%, p = 0.003). In compliant patients (n = 25) there was also a significantly greater increase in HDL cholesterol levels in the fenofibrate group (+19.9%) compared to placebo (-4.7%, p = 0.001). Changes in measured creatinine clearance were not significantly different between the groups and there were no serious adverse effects of treatment. CONCLUSION: Fenofibrate therapy combined with dietary modification effectively reduced triglyceride levels in renal insufficiency patients without serious adverse effects.  相似文献   
62.
Nystagmus signaling vestibular dysfunction was observed after vibratory stimulation with a 100 Hz ABC stimulator in a population of 36 patients with unilateral labyrinthine pathology (ULP) (pre and postoperative neuromas, vestibular neurectomies) and 10 patients with vestibular neuritis. The stimulus was applied on 3 bony points of the skull (vertex and 2 mastoids) and 2 muscular points of the neck (right and left posterior cervical region). These results were compared with those in 95 normal subjects and 19 cases of central disease and were correlated on the same day with results of the caloric test and head shaking test (HST). A consistent nystagmus was found in only 6 % of the normal subjects (specificity 94 %) and in 10 % of the central lesions, but in 94 % of the 36 peripheral ULP. The sensitivity of the test was equivalent to the HST. The signal was optimized in 30 patients: stimulus frequency, amplitude, stimulator mass, form of the contact, patient tolerance. The best results were obtained for a frequency of 100 Hz and an amplitude of 0.5 mm (there was no response under 0.1 mm vibration amplitude). Under videoscopy and 3D videonystagmography, the direction or side of the nystagmus was constant, but its axis (horizontal, oblique or rotational) changed according to the location of the stimulator: on the mastoid (elective location of stimulation with responses in 94 % of cases) the axis was most often horizontal or horizontal rotational. On the vertex location (where nystagmus was observed in 60 % of cases) the axis of nystagmus was most often rotational or oblique and sometimes horizontal-rotational. The nystagmus showed short latency (less than 200 ms). It started and stopped as stimulation was initiated and interrupted. Nystagmus persisted for the duration of patient tolerance. This nystagmus generally signifies unilateral vestibular weakness rather than vestibular predominance. It is a good indicator of unilateral vestibular dysfunction and could serve as a useful test in clinical practice. We discuss the origin of the nystagmus which may originate in muscle proprioception (by propagation of the vibration to neck muscles) or in the labyrinth (simultaneous excitation of 3 canals on each side).  相似文献   
63.
OBJECTIVE: To determine whether use of a primary pull-through would result in equivalent perioperative and long-term complications compared with the two-stage approach. SUMMARY BACKGROUND DATA: During the past decade, the authors have advanced the use of a primary pull-through for Hirschsprung disease in the newborn, and preliminary results have suggested excellent outcomes. METHODS: From May 1989 through September 1999, 78 infants underwent a primary endorectal pull-through (ERPT) procedure at four pediatric surgical sites. Data were collected from medical records and a parental telephone interview (if the child was older than 3 years) to assess stooling patterns. A similar group of patients treated in a two-stage fashion served as a historical control. RESULTS: Mean age at the time of ERPT was 17.8 days of life. Comparing primary ERPT with a two-stage approach showed a trend toward a higher incidence of enterocolitis in the primary ERPT group compared with those with a two-stage approach (42.0% vs. 22.0%). Other complications were either lower in the primary ERPT group or similar, including rate of soiling and development of a bowel obstruction. Median number of stools per day was two at a mean follow-up of 4.1 +/- 2.5 years, with 83% having three or fewer stools per day. CONCLUSIONS: Performance of a primary ERPT for Hirschsprung disease in the newborn is an excellent option. Results were comparable to those of the two-stage procedure. The greater incidence of enterocolitis appears to be due to a lower threshold in diagnosing enterocolitis in more recent years.  相似文献   
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65.
Trichloroethylene (TCE) is a prevalent occupational and environmental contaminant that has been reported to cause a variety of toxic effects. Here, we have undertaken studies to test the hypothesis that TCE exposure adversely affects sperm function and fertilization. Sperm retrieved from mice exposed to TCE (1000 ppm) by inhalation for 1 to 6 weeks were incubated in vitro with eggs isolated from superovulated female mice. The number of sperm bound per egg was significantly decreased when mice were exposed to TCE for 2 and 6 weeks but not at exposures of 1 and 4 weeks. In vivo fertilization was also determined in superovulated female mice mated with males exposed to TCE for 2 to 6 weeks. The percentages of eggs fertilized, as assessed by the presence of two pronuclei, were significantly decreased after 2 and 6 weeks of TCE exposure. A slight but insignificant decrease was observed after 4 weeks of TCE exposure. The direct effects of TCE and its metabolites, chloral hydrate (CH) and trichloroethanol (TCOH), on in vitro sperm-egg binding were also investigated. Sperm-egg binding was significantly decreased when sperm were pretreated with CH (0.1-10 microg/mL). Significantly lower levels of sperm-egg binding were also detected with TCOH (0.1-10 microg/mL), although the decreases were not as pronounced as those for CH. These results showed that TCE exposure leads to impairment of sperm fertilizing ability, which may be attributed to TCE metabolites, CH, and TCOH.  相似文献   
66.
Penile plethysmography (PPG) is a measure of sexual interests that relies heavily on the stimuli it uses to generate valid results. Ethical considerations surrounding the use of real images in PPG have further limited the content admissible for these stimuli. To palliate this limitation, the current study aimed to combine audio and visual stimuli by incorporating computer-generated characters to create new stimuli capable of accurately classifying sex offenders with child victims, while also increasing the number of valid profiles. Three modalities (audio, visual, and audiovisual) were compared using two groups (15 sex offenders with child victims and 15 non-offenders). Both the new visual and audiovisual stimuli resulted in a 13% increase in the number of valid profiles at 2.5 mm, when compared to the standard audio stimuli. Furthermore, the new audiovisual stimuli generated a 34% increase in penile responses. All three modalities were able to discriminate between the two groups by their responses to the adult and child stimuli. Lastly, sexual interest indices for all three modalities could accurately classify participants in their appropriate groups, as demonstrated by ROC curve analysis (i.e., audio AUC = .81, 95% CI [.60, 1.00]; visual AUC = .84, 95% CI [.66, 1.00], and audiovisual AUC = .83, 95% CI [.63, 1.00]). Results suggest that computer-generated characters allow accurate discrimination of sex offenders with child victims and can be added to already validated stimuli to increase the number of valid profiles. The implications of audiovisual stimuli using computer-generated characters and their possible use in PPG evaluations are also discussed.  相似文献   
67.
Primary vertebral osteosarcoma is a rare type of osteosarcoma, differing from the appendicular forms by an incidence peak occurring at a higher age and a poorer prognosis, due to the difficulties of the surgical treatment. We present five cases of histologically proven primary vertebral osteosarcomas followed in our institution between 2004 and 2012. They allow to illustrate some essential radiologic features, useful to evoke this rare entity.  相似文献   
68.
This article presents an anthropologic study of the growth and developmental changes that occur within the bony components of the temporomandibular joint. The material used was provided by the Department of Physical Anthropology of the Smithsonian Institution Museum of Natural History, Washington, D.C.

Based on a Class I normal occlusion, the authors selected a total of 100 skulls with mandibles from the Aleutian Islands collection. These skulls, which were from 2-to 20-year-old subjects, were divided into four age groups. The approximate age of each skull was determined by charts based on eruption sequence, the number of permanent teeth present, and suture closure.

Anatomic landmarks and anthropologic techniques were used to make direct linear measurements on the bony components of the 200 temporomandibular joints. Three-dimensional measurements were made on the condyles, fossae, and articular eminences of each skull.

Several variables were chosen for statistical analysis: (1) The size of the individual components of the TMJ within each age group. (2) The changes with age in the anteroposterior, medial-lateral, and vertical dimensions of the individual TMJ components. (3) Asymmetries in size between the right and the left TMJ components. (4) The interrelationship of the individual TMJ components as seen in their growth changes.

The results obtained from the various measurements used in this study were compared to the findings of a number of earlier studies.  相似文献   
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