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81.
OBJECTIVE: The objective of this study was to evaluate work-related asthma among health maintenance organization (HMO) members. Recent reports suggest that the incidence of work-related asthma may be much higher than Sentinel Event Notification Systems for Occupational Risks (SENSOR) data estimate. METHODS: Using the HMO's electronic medical record, we identified 1,747 persons with evidence of new or recurrent asthma. Interviews with 352 of them elicited information about workplace exposures, symptoms, and home environment. Industrial hygienists rated the potential asthmagenicity of the respondents' work environments. RESULTS: Based on the industrial hygienist ratings and self-reported work-relatedness of asthma symptoms, we classified 33% of those interviewed as having potentially work-related asthma, suggesting an overall work-related asthma incidence/recurrence rate of 28 cases per 10,000. CONCLUSIONS: The contribution of occupation to the occurrence of adult onset asthma may be much higher than typically suggested in the literature.  相似文献   
82.
OBJECTIVE: To estimate the incidence of Churg-Strauss syndrome (CSS) among a large population of asthma drug users. METHODS: A retrospective study was conducted among patients who had been dispensed asthma drugs at 3 managed care organizations. Adults who received >or =3 dispensings of an asthma drug during any consecutive 12-month period between January 1, 1995 and June 30, 2000 were identified. Information on patient age, gender, enrollment status, asthma drugs dispensed, and inpatient and outpatient diagnoses and procedures was obtained from automated databases. Chart reviews were performed on persons identified by combinations of diagnostic and billing codes indicative of CSS. A rheumatologist reviewed abstracted information on all subjects; those who met >or =2 American College of Rheumatology criteria for CSS were reviewed by 2 clinical experts. Each clinical expert independently rated the cases; disagreements were resolved by consensus. Cases classified as having "probable/definite" CSS were included in these analyses. The incidence of CSS was estimated overall and according to patient gender, age, and calendar year. RESULTS: From a population of 184,667 asthma drug users contributing 606,184 person-years of exposure, 21 incident cases of CSS were identified (overall incidence of 34.6 per million person-years; 95% confidence interval 21.4 to 53.0). Incidence rates did not differ by gender and age group. The incidence rates for 1995, 1996, 1997, 1998, 1999, and the first 6 months of 2000 were 0, 22, 52, 75, 14, and 14 per million person-years respectively. CONCLUSIONS: Results from this population-based study suggest a somewhat lower incidence of CSS in asthma drug users than previously reported and provides important information as to the risk of developing CSS from a population-based perspective.  相似文献   
83.
Stereotypy is a relatively common behavioral disorder displayed by individuals with developmental disabilities, including autism. In this paper, we review selected studies on neurobiological interpretations of stereotypy and pharmacological interventions for stereotypy. Specifically, we review studies that evaluated the effects of serotonin uptake inhibitors (e.g., clomipramine) or opioid antagonists (e.g., naltrexone) on stereotypy displayed by humans. Throughout, suggestions are made for the incorporation of behavioral methods into this area of research.  相似文献   
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Carcinosarcoma of the uterus has been poorly characterized on cervicovaginal (Pap) smears, and we examine whether they effectively screen for carcinosarcoma and whether an abnormal Pap smear result has any clinical importance. Twenty-five patients with histologically confirmed carcinosarcoma had a conventional Pap smear shortly before diagnosis. Eleven smears (44%) originally were read as abnormal (malignant or atypical), and 4 additional cases were read as abnormal on retrospective review (15/25 [60%]). All malignant elements were epithelial, and 2 cases (8%) had atypical spindle cells, but no diagnostic sarcoma. Cervical involvement was the only histologic parameter correlating with an abnormal Pap smear result (P = .04). Univariate analysis found stage III or IV disease was an adverse prognostic sign compared with stage I or II disease (mean survival, 8 vs 36 months, respectively; P = .001), and multivariate analysis indicated that an abnormal Pap smear result correlated with worse survival (P = .023). The conventional Pap smear is insensitive (60%) for detecting carcinosarcoma, but when the result is abnormal, the Pap is an important stage-independent adverse prognosticator.  相似文献   
86.
BACKGROUND: In preterm infants there is a high risk of transmission of cytomegalovirus (CMV) via breast milk from seropositive mothers with reactivation of the virus during lactation. There is little information about the long term sequel of early postnatally acquired CMV infection in pre-term infants. This study aimed to investigate whether there was an increased frequency of impaired neurodevelopmental outcome and sensorineural hearing loss in preterm infants with postnatally acquired CMV infection through transmission by CMV-positive breast milk. METHODS: Twenty-two preterm infants [median birth weight, 1020 g (range, 600 to 1870 g); median gestational age, 27.6 weeks (range, 23.6 to 32 weeks] with early postnatally acquired CMV infection by breast-feeding (onset of viruria between Days 23 and 190 postnatally) were compared with 22 CMV-negative preterm infants individually matched for gestational age, birth weight, gender, intracranial hemorrhage and duration of ventilation. At 2 to 4.5 years of age, follow-up assessments were conducted consisting of neurologic examination, neurodevelopmental assessment and detailed audiologic tests. RESULTS: None of the children had sensorineural hearing loss. There was no difference between the groups with regard to neurologic, speech and language or motor development. CONCLUSION: The results of this study suggest that early postnatally acquired CMV infection via CMV-positive breast milk does not have a negative effect on neurodevelopment and hearing in this group of patients. Because we studied a small number of infants, further follow-up studies are warranted in preterm infants with early postnatally acquired CMV infection.  相似文献   
87.
Background Patients with prostate cancer with a pre-operative prostate-specific antigen (PSA) τ;15ng/ml who undergo radical retropubic prostatectomy (RRP) generally do not have a good outcome, yet may have organ-confined cancer and should be offered the option of surgery. Aim To assess the outcome of patients who underwent RRP with a pre-operative PSA ≥ 15ng/ml. Methods Thirty-four patients, mean pre-operative PSA: 25.46ng/ml (15.03–76.6) and mean Gleason score: 6.4 (5–9) were assessed. Results Two groups were identified. Group I: 41% (14/34) have no biochemical recurrence to mean follow up of 58 months (30–106). Mean PSA: 18.8ng/ml (15.03–25.84). Mean Gleason score: 6.1 (5–7). Clinical stage: T1c in 80%. No patient had seminal vesicle or lymph node involvement. Group II: 59% (20/34) have biochemical recurrence or died (3) from their disease to mean follow up of 66 months (36–98). Mean PSA: 28.9ng/ml (15.28–76.6). Mean Gleason score: 6.7 (5–9). Clinical stage: T1c in 25%. Eleven patients had seminal vesicle (8) involvement or positive lymph nodes (3) or both (2). Conclusion RRP seems feasible in patients whose pre-operative PSA is between 15 and 25ng/ml with stage T1c, Gleason score ≤ 7 and negative lymph node frozen section.  相似文献   
88.
Experiments were conducted to determine if the chronic absence of the neurotransmitter oxytocin (OT) in null mice resulted in alterations in the responsiveness and abundance of central OT receptors. Self-grooming elicited by intracerebroventricularly administered OT was studied as an indicator of the activation of central OT receptors and autoradiography was used to map the distribution and density of OT receptors in OT null and wild type mice. The intracerebroventricular administration of OT, but not vehicle, artificial cerebrospinal fluid (aCSF), produced a robust increase in grooming behavior in both OT null and wild type animals, P<.001. However, OT-induced grooming was significantly greater in OT null than wild type mice, P<.005. The enhanced grooming was selective to OT as indicated by the finding that grooming to intracerebroventricular arginine vasopressin (AVP) was of the same magnitude in both OT null and wild type mice. OT-induced grooming appears to be mediated through the activation of OT receptors because pretreatment of animals with an OT antagonist, Atosiban, abolished OT-induced grooming, but not AVP-induced grooming. OT receptor distribution and binding in brains of OT null and wild type mice were examined by autoradiography and were not significantly different. The results indicate that the chronic absence of OT in null mice leads to an increase in OT receptor responsiveness that contributes to the augmented grooming activity elicited by centrally administered OT.  相似文献   
89.
The antiobesity agent, fenfluramine, produces hypothermia in rodents by an, as yet, uncharacterized mechanism. The present study was conducted in conscious rats to determine if fenfluramine-induced hypothermia was associated with cutaneous dilation. In animals maintained at 16 degrees C, core body temperature (T(CORE)) was measured telemetrically, and tail surface temperature was monitored with thermocouples fixed to the tail (T(TAIL)). D-Fenfluramine (10 mg/kg ip) produced a rapid increase in T(TAIL) of 7.7+/-0.4 degrees C (P<.001) and a decline in T(CORE) of 4+/-0.3 degrees C (P<.001). Two findings indicate that the increase in T(TAIL) was due to the withdrawal of a sympathetic vasoconstrictor tone. First, pretreatment with the ganglionic blocker, pentolinium, prevented fenfluramine-induced changes in T(TAIL). Second, when sympathetic tone to the tail was physiologically withdrawn by increasing the environmental temperature to 28 degrees C, fenfluramine treatment produced no increase in T(TAIL). Moreover, the effects of fenfluramine on T(TAIL) and T(CORE) depended on the uptake of fenfluramine into serotonergic neurons because these effects were markedly attenuated by pretreatment with the selective serotonin re-uptake inhibitor, fluoxetine. The hypothermic effect of fenfluramine occurred despite the fact that total body oxygen consumption increased by 20%. The results suggest that heat loss due to the dilation of the cutaneous circulation contributes to fenfluramine-induced hypothermia.  相似文献   
90.
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