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101.
Widespread use of contemporary imaging techniques (ultrasound, computerized axial tomography, and magnetic resonance imaging scans) have led to the incidental discovery of asymptomatic adrenal neoplasms with increasing frequency. Patients with such adrenal "incidentalomas" typically have no clinical manifestations of adrenal cortical hyperfunction at the time of discovery. We have studied 122 patients with asymptomatic adrenal masses ranging in size from 2 to 7 cm in diameter from 1978 to 1988. Selected patients, after adrenal metastases, pheochromocytoma, myelolipomas, and cysts were ruled out, were further evaluated for adrenal cortical hyperfunction by measuring urinary 17-hydroxysteroids, 17-ketosteroids, and free cortisol, serum A.M., P.M. cortisol, and plasma ACTH levels. These values were also measured before and after dexamethasone suppression. NP-59 adrenal scintiscans were performed on all patients. Six patients were identified with sub-clinical Cushing's syndrome. Baseline cortisol levels were normal in each of these patients. Loss of diurnal rhythm appeared to be the most sensitive indicator of abnormal adrenal cortical function. When adrenalectomy is performed in such patients, especially when contralateral adrenal gland suppression is evidenced by NP-59 scanning or other biochemical assessment, perioperative steroids should be administered in a manner similar to that used for patients with symptomatic Cushing's syndrome. Unilateral adrenalectomy in a patient with an asymptomatic adrenal adenoma, insufficiently studied, may result in Addisonian crisis.  相似文献   
102.
103.
Modified Allen pictures to assess amblyopia in young children   总被引:1,自引:0,他引:1  
D L Mayer  R D Gross 《Ophthalmology》1990,97(6):827-832
To produce a test of visual acuity for young children that is more sensitive to amblyopia than current preschool vision tests, the authors surrounded four Allen pictures with "crowding" bars. This modified Allen test was evaluated by measuring acuity of amblyopic children (n = 28) and children (n = 10) and adults (n = 5) with normal eyes. Mean acuities of amblyopic eyes for the modified pictures was 0.8 octaves or nearly three logMar Snellen lines poorer than for the isolated pictures. For nonamblyopic and normal eyes modified picture acuity averaged 0.1 to 0.4 octaves poorer than isolated picture acuity. Average acuities of amblyopic eyes (n = 22) for the modified pictures agreed with line letter acuities. These results suggest that the modified picture test induces contour interaction similar to that of line letter tests, and thus, is a more sensitive test of amblyopia in the preschool child than isolated symbols.  相似文献   
104.
Crack users: the new AIDS risk group?   总被引:1,自引:0,他引:1  
Crack cocaine, a smokable form of cocaine hydrochloride, is now widely available in American inner cities. Reports of high rates of unprotected sexual activity among crack users, coupled with reports of high rates of sexually transmitted diseases (STDs), have raised fears that this population of drug users may soon be contracting and disseminating sexually transmitted HIV. In a study of 205 black adolescent crack users conducted in Oakland and San Francisco, California, 101 respondents (49% of the sample) who reported using crack in combination with sexual activity were examined. Those respondents who reported having a history of one or more STD were compared using discriminant analysis (DA). A successful discrimination (canonical correlation = 0.61, p = 0.000) identified five variables that distinguished those with a STD history from those with no STD history: gender (being female) (p = 0.000), frequency of marijuana use (p = 0.005), response to the question; "Do you plan for sex or does it just happen?" (p = 0.002), response to the statement, "I use drugs to get away from my problems" (0.029), and response to the question, "Do you agree that sex doesn't feel as good when you use a condom?" (p = 0.006). The selection of these variables was thought to represent an underlying passivity in the way that crack users who combine crack use with sex approach sexual activity.  相似文献   
105.
Down syndrome regression disorder (DSRD) is a clinical symptom cluster of acute or subacute neurocognitive regression in otherwise health persons with Down syndrome. The objective of this study was to evaluate if adverse childhood experiences (ACEs) were more prevalent in children with DSRD than those with DS alone. A survey-based, cohort-based study was performed. Caregivers of individuals with DSRD with onset of symptoms between age 10 and 30 years and DS alone were administered the ACEs questionnaire via an online REDCap survey. A total of 159 responses were collected after excluding incomplete surveys and those not meeting criteria for DSRD. Individuals with DSRD were not more likely to experience ACEs (p = 0.18, 95% confidence interval [CI]: 0.43–1.17). In those with ACEs prior to the onset of symptoms, the median time prior was 7 months (interquartile range: 5–10). Individuals with DSRD were more likely to report three or more ACEs (52, 33%) compared to those with DS alone (39, 22%) (p = 0.02, 95% CI: 1.08–2.87). Exposure to ACEs were not predictive of response to particular therapeutic interventions although those with multiple ACEs 3 months prior to the onset of symptoms was associated with lower response rates to benzodiazepines and immunotherapy (p = 0.02, 95% CI: −3.64–−1.13). This study provides preliminary data that individuals with DSRD experience ACEs at a similar rate to individuals with only DS alone, although three or more ACEs, often preceding the onset of symptoms, was more prevalent in individuals with DSRD.  相似文献   
106.
This study examined the role of perceived token resistance and previous sexual contact on women's ability to discriminate when a female wants her partner to stop his sexual advances. Participants included 101 White female undergraduate students and were randomly assigned to one of the four conditions: 1) perceived resistance with genital contact; 2) no resistance with genital contact; 3) perceived resistance with no genital contact; and 4) no resistance without genital contact. Subjects listened to an audiotaped date rape after being informed of the couple's sexual history based on the condition assigned to them. They were also informed that the couple had been on five previous dates, in which the man had manipulated the woman's breasts or genitals. In addition, the woman did not object to this contact, or the woman initially objected to the contact but subsequently stopped resisting contact. Participants in the perceived token resistance conditions took significantly longer to determine when the man should refrain from attempting further sexual contact. The findings of this study could be used to increase information on date rape, to educate individuals about the responses associated with date rape, and to reinforce rules concerning appropriate sexual behavior.  相似文献   
107.
108.
The contribution of the complement system to cerebral ischemic and ischemia/reperfusion injury was examined in a rabbit model of thromboembolic stroke by delivery of an autologous clot embolus to the intracranial circulation via the internal carotid artery. A two-by-two factorial design was employed to study the impact of complement depletion via pretreatment with cobra venom factor (CVF, 100 U/kg i.v.) in the setting of permanent (without tissue plasminogen activator; t-PA) and transient (with t-PA) cerebral ischemia. Thirty-two New Zealand white rabbits were assigned to one of four groups (n=8, each group): control without t-PA, control with t-PA, CVF without t-PA and CVF with t-PA. In the complement intact animals, t-PA administration resulted in an approximate 30% reduction in infarct size when compared to the group not receiving t-PA (20.4+/-6.6% of hemisphere area vs. 30.1+/-7.2%; mean+/-SEM). However, infarct sizes in the complement depleted rabbits, with (30.7+/-8.2%) or without (30.2+/-7.9%) t-PA, were no different from the control group receiving no therapy. Similarly, no difference in regional cerebral blood flow or final intracranial pressure values was noted between any of the four groups. Complement activation does not appear to be a primary contributor to brain injury in acute thromboembolic stroke.  相似文献   
109.
Summary. Perinatal hypoxia is known as a high risk factor for the development of long-lasting abnormalities in dopaminergic system. The early developmental alterations of dopamine (DA) metabolism induced by hypoxia could contribute to these abnormalities. To understand the hypoxia-induced changes of intra- and extracellular dopamine levels and its main metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), in immature dopaminergic neurons, we compared these changes in rat mesencephalic and diencephalic cell cultures on day in vitro (DIV) 2 (immature cells), DIV 8 and DIV 13 (mature cells). Cell cultures were exposed to an oxygen-free gas mixture in a Billups chamber for 2–4 hours. Mature cell cultures responded to hypoxia with an increase of DA levels in the cells and in the medium during the first 45 min (by an average of 57 and 114% respectively). Thereafter, DA levels decreased, and returned to the baseline within the next 30 min. The cellular DA levels continued to decrease up to 15% of the baseline during 255 min hypoxia whereas the extracellular DA content stabilized at the prehypoxic levels. Immature cell cultures (DIV 2) in contrast to mature ones, were unable to maintain normal extracellular DA levels during hypoxia and showed a decrease of the cellular and extracellular levels to 50% of the prehypoxic levels. DOPAC and HVA changes mimick, however, at a lower level, the pattern of DA changes during the exposure to hypoxia. In principle, in the diencephalic cell culture similar effects of hypoxia exposure on the investigated parameters were found (studied during 0–120 min). The present study demonstrates that mature and immature dopaminergic cells differ in the regulation of the extra- and intracellular DA levels during hypoxia. In immature cells the low synthetic capacity of tyrosine hydroxylase and the deficient capacities of the transport and storage processes result in decreased extracellular DA levels. This could be an important factor for the long-term modulation of the expression of tyrosine hydroxylase and subsequent long-term behavioral and/or neurological abnormalities induced by perinatal hypoxia. Received June 8, 1998; accepted July 21, 1998  相似文献   
110.
PURPOSE: To compare the 2.0% dorzolamide/0.5% timolol fixed combination (COSOPT; Merck & Co., Whitehouse Station, NJ) to 0.5% timolol plus 2.0% pilocarpine given concomitantly, and to determine patient preference, tolerability, and impact on daily life in patients with elevated intraocular pressure (IOP). METHODS: Two multi-center, randomized, cross-over, observer masked studies were conducted, one in the United States (97 patients) and one in Europe (93 patients). The Comparison of Ophthalmic Medications for Tolerability questionnaire was used to assess patient preference and perception of side effects and activity limitations resulting from study medications. Intraocular pressure was measured before and 2 hours after the morning dose of study medication (hour 0 and hour 2). RESULTS: In both studies, among patients with a preference, the combination was preterred to timolol plus pilocarpine by a ratio of 4 to 1. The most commonly cited reason for this preference was side effects. Patients in both studies also reported that the combination interfered significantly less with daily life in terms of side effects and activity limitations. They also reported missing significantly fewer doses of study medication while taking the combination and being significantly more satisfied with it. The efficacy of these two treatments was not significantly different, based on IOP measurements at hour 0 and 2 hours after administration. Patients reported significantly more adverse events while receiving timolol plus pilocarpine in both studies, and in the U.S. study, significantly more patients discontinued therapy while receiving timolol plus pilocarpine than while receiving the combination. CONCLUSION: Compared with timolol plus pilocarpine, patients preferred the combination of 2% dorzolamide/0.5% timolol, and reported less interference in daily activities, better tolerability, and better compliance with therapy.  相似文献   
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