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41.
The ability to discriminate perfect from imperfect mirror symmetry was examined at the fovea and at eccentricities out to 10 degrees in the nasal visual field. A 2-AFC method of constant stimuli was employed in which a bilaterally symmetric pattern was presented in one interval and a degraded version of this symmetric pattern in the other. The subject's task was to decide which interval contained the perfectly symmetric pattern. Pattern size was varied by changing the viewing distance. Probit analysis revealed the degree of asymmetry corresponding to 75% correct performance. Given sufficient size scaling, perfectly symmetric stimuli can be discriminated from degraded symmetric stimuli in extra-foveal vision. Spatial scaling with an E2 value similar to that for positional acuity was successful in removing the eccentricity dependence for the task. 相似文献
42.
Schroeder RE Acker BJ Schell MG Troyer JE Whitaker NK 《Hospital & health services administration》1992,37(4):491-502
This article analyzes the implementation of a traditional Economic Grand Rounds (EGR) program in a teaching hospital. The conclusions are that the original concepts of EGR--presentations of treatment costs by clinicians in a grand rounds setting, reinforcement of agreed changes in practice patterns, and subsequent evaluation and participation--are still valid but are inadequate to ensure a successful program. Other factors must be added if EGR is to attain its goals. These factors are administrative and nursing involvement, a provision to make policy changes, and incentives for the medical staff. This article also outlines areas of potential savings achieved through an EGR program in laboratory testing, preoperative laboratory testing, and intravenous therapy with antibiotics. 相似文献
43.
Predictive value of serial carcinoembryonic antigen levels in long-term follow-up of ovarian cancer.
The predictive value of serial levels of carcinoembryonic antigen (CEA) in tumor monitoring was examined in 213 patients with ovarian cancer; each patient had been followed-up at monthly intervals for at least 12 months. CEA was not detectable throughout the period of observation in 35% of the patients. In general. patterns showing a disappearance of CEA or persistently low levels were associated with a good prognosis, whereas those showing a reappearance or highly elevated and rising levels were associated with a poor prognosis. A transient reappearance of CEA was observed in 10 patients; this did not appear to be associated with tumor recurrence or progression. "False positive" results were obtained in 6 patients in whom no tumor has been clinically detectable to date. "False negative" results were obtained in 4 patients with obvious tumor progression. In terms of a good or poor prognosis, the use of CEA levels was highly accurate in patients with minimal or no residual disease (97% and 89%, respectively); the rate fell to 62% in patients with extensive disease. As the clinical significance and limitations become better known, serial CEA levels should contribute substantially to the monitoring of patients with ovarian cancer. 相似文献
44.
Treatment of selected neuromuscular patients with posterior instrumentation and arthrodesis ending with lumbar pedicle screw anchorage 总被引:3,自引:0,他引:3
STUDY DESIGN: This is a retrospective analysis of 23 patients with severe neuromuscular spinal deformity treated with posterior instrumentation and fusion ending in the lumbar spine. OBJECTIVES: The purposes of this study were to determine the safety and efficacy of stopping posterior instrumentation constructs in the lumbar spine with pedicle screw anchorage. SUMMARY OF BACKGROUND DATA: There are sparse data in the peer-reviewed literature regarding indications and outcomes in patients with neuromuscular disorders for instrumented fusion ended short of the pelvis with transpedicular fixation. METHODS: The average age of patients at surgery was 18.4 years (range, 10-61 years). Additional anterior discectomy and fusion were performed in four patients with large, stiff curves. No patient received anterior instrumentation. Criteria for exclusion of the pelvis from the fusion were less than 15 degrees of pelvic obliquity as a result of a compensatory curve below the major curve(s), the absence of problematic lower extremity contractures, and, often, the potential for ambulation. Process and clinical outcomes and complications were analyzed. RESULTS: Radiographic follow-up was available in 21 patients at an average of 62 months (range, 24-110 months) after surgery. Their average Cobb angle was 71 degrees before surgery, 25 degrees after surgery (64% correction), and 32 degrees at follow-up (54% correction). Their average spinal-pelvic obliquity was 6 degrees before surgery, 5 degrees after surgery, and 6 degrees at follow-up. The average lower instrumented vertebra was lumbar 3.7. Clinical follow-up was available for all 23 patients for an average of 61 months (range, 24-110 months). There were no perioperative deaths, deep wound infections, pseudarthroses, or instrument failures. Outcomes based on responses to questionnaires completed by patient, parent, or caregiver were highly satisfactory in 20 patients (87%), satisfactory in 2 patients (9%) and neither satisfactory nor unsatisfactory in 1 patient (4%). CONCLUSION: Posterior instrumentation and arthrodesis using lumbar lower instrumented vertebra pedicle screw anchorage can be performed safely and effectively, in selected patients patients with scoliosis and minimal pelvic obliquity. 相似文献
45.
Anthony R. Cox Simon Whitaker Angela M. Alexander 《The International journal of pharmacy practice》2003,11(1):25-32
Objective To analyse the content of messages to an internet mailing list for UK pharmacists and to ascertain if the list was performing a continuing professional development (CPD) function. Method For one month all messages to the main list were categorised by topic; details of the gender of the correspondent and their sector of the profession were noted. Members were surveyed using an internet questionnaire. Setting The population of subscribers to the mailing list at http:www.private‐rx.com Key findings The top three categories of e‐mails posted to the list were clinical pharmacy (20%), pharmacy politics (18%) and non‐pharmacy chat (14%). Other subjects included legal issues, the Drug Tariff, government policy, business, risk management and e‐mails of a personal and supportive nature. The survey obtained a 46% response rate. Ninety‐eight per cent of respondents found the list valuable. Respondents reported increased face to face and Internet contact with other pharmacists after joining the list. Forty‐four per cent of respondents said their practice had changed as a result of information gained from the mailing list. Qualitative data self‐reported by respondents indicated increased self‐perceived competence, confidence, knowledge and skills. Approaches to CPD had also been re‐examined. Listening to peers' views and overcoming isolation was seen as important. Conclusion Private‐Rx provided pharmacists with a rapid route for information gain, had perceived benefits and appeared to have brought about changes in practice. Internet discussion enables CPD without the restriction of time or place and reaches pharmacists who are under‐represented in formal education programmes. 相似文献
46.
OBJECTIVE: The goal of this study was to investigate the clinical and paraclinical features, treatment, and outcomes of patients with multiple sclerosis (MS) and coexisting spinal cord compression secondary to either cervical spondylosis or cervical disc disease. Patients with MS commonly experience neurological disabilities that present as myelopathy associated with bladder dysfunction. For some patients with MS, however, this neurological deterioration may result from coexisting spinal cord compression attributable to either spondylosis or a herniated disc. Overlapping symptoms of the two conditions do not allow clear clinical determination of the underlying cause of worsening. METHODS: Patients with MS who underwent cervical decompression surgery were selected. Medical records were retrospectively reviewed, to collect data on their pre- and postoperative clinical courses. RESULTS: Nine women and five men with definite MS were selected for cervical decompression surgery to treat neurological deterioration considered to be at least partially attributable to spinal cord compression. The most common symptoms were progressive myelopathy (n = 13), neck pain (n = 11), and cervical radiculopathy (n = 10). Bladder dysfunction was notably absent among these patients with MS with moderate disabilities. Surgical intervention was frequently delayed because the neurological deterioration was initially thought to be attributable to MS. The majority of patients experienced either improvement or stabilization of their preoperative symptoms in the immediate postoperative period; three subjects (21%) maintained this improvement after a mean follow-up period of 3.8 years. No MS relapses, permanent neurological worsening, or serious complications resulting from surgery or general anesthesia were noted. CONCLUSION: Carefully selected patients with MS and cervical spinal cord compression secondary to either spondylosis or disc disease may benefit from surgical decompression, with minimal associated morbidity. Clinical features (especially neck pain and cervical radiculopathy) and magnetic resonance imaging may assist clinicians in differentiating between the two conditions and may guide appropriate treatment without undue delay. 相似文献
47.
Samuel R. Whitaker Aldo Cordier Serge Kosjakov Ronald Charbonneau 《The Laryngoscope》1998,108(2):195-199
Exostoses of the external auditory canal can occur in patients living in coastal, southern California communities with a history of cold-water aquatic activities such as ocean surfing and swimming. Although most canal exostoses are asymptomatic, patients with canal obstruction greater than 80% can have recurrent episodes of external otitis and a related conductive hearing loss. In most cases, medical treatment resolves the symptomatic external otitis and related hearing loss. Patients recalcitrant to medical treatment are candidates for surgical removal of the exostoses. This report reviews the authors' surgical experience with 18 patients (27 ears) who have undergone surgical removal of exostoses. Their preferred surgical technique of transmeatal removal of exostoses with a specialized mallet and thin chisel under local anesthesia is described. 相似文献
48.
A case of reflex sympathetic dystrophy is presented in a 12-year-old girl with comorbid conversion disorder. Her identical twin also had a conversion disorder. This is the first reported case of coexistence of reflex sympathetic dystrophy and conversion disorder. It is important for clinicians to be aware that these conditions may coexist since the presentation of symptoms differ, even though there are shared features of treatment. 相似文献
49.
Arif JM; Gairola CG; Glauert HP; Kelloff GJ; Lubet RA; Gupta RC 《Carcinogenesis》1998,19(8):1515-1517
The present study investigated the effects of dietary oltipraz on cigarette
smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats
were exposed daily to sidestream cigarette smoke in a whole- body exposure
chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained
on control diet while another group received the same diet supplemented
with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz,
starting 1 week prior to initiation of smoke exposure until the end of the
experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated
32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5
predominated in both the lung and the heart while adduct nos 3 and 2
predominated in the trachea and bladder, respectively. Quantitative
analysis revealed that the total adduct level was the highest in lungs
(270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48
adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides)
and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz
treatment reduced the adduct levels in lungs and bladder by >60%, while
the reduction in lungs in the low-dose group was approximately 35%. In
trachea, the effect of low and high dietary oltipraz on smoke DNA adduction
was equivocal, while smoke-related DNA adducts in the heart were minimally
inhibited by high-dose oltipraz. In a repeat experiment that employed a
3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to
inhibit the formation of DNA adducts in rat lungs and trachea by 80 and
65%, respectively. These data clearly demonstrate a high efficacy of
oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts
in the target tissues.
相似文献
50.
Chen YH Dale TJ Romanos MA Whitaker WR Xie XM Clare JJ 《The European journal of neuroscience》2000,12(12):4281-4289
The type III voltage-gated sodium channel was cloned from human brain. The full-length cDNA has 89% identity with rat type III, and the predicted protein (1951 amino acids) has 55 differences. The expression pattern of human type III mRNA was determined in adult brain tissue and, in contrast to rat, was detected in many regions, including caudate nucleus, cerebellum, hippocampus and frontal lobe. The human type III channel was stably expressed in Chinese hamster ovary (CHO) cells and its biophysical properties compared to the human type II channel using identical conditions. The voltage dependence and kinetics of activation were found to be similar to that of type II. The kinetics of inactivation of the two human subtypes were also similar. However, type III channels inactivated at more hyperpolarized potentials and were slower to recover from inactivation than type II. When expressed in human embryonic kidney (HEK293T) cells, type III channels produced currents with a prominent persistent component, which were similar to those reported for rat type II [Ma et al. (1997) Neuron, 19, 443-452]. However, unlike type II, this was prominent even in the absence of coexpressed G-proteins, suggesting type III may adopt this gating mode more readily. The distinct properties of the channel, together with its wide distribution in adult brain, suggest that in humans, type III may have important physiological roles under normal, and perhaps also pathological conditions. 相似文献