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1.
Carlo Bertucci Enrico Domenici Piero Salvadori 《Journal of pharmaceutical and biomedical analysis》1990,8(8-12):843-846
The application of a circular dichroism (c.d.) detection system in HPLC using a chiral stationary phase is presented. The simultaneous measurement of the absorbance and c.d. signal allows the evaluation of the anisotropy factor (g = Δ/) and thus the determination of the enantiomeric excess (e.e.) of the eluates. When this detection system is used in preparative chiral chromatography the collection of the enantiomeric fractions can be readily optimized. 相似文献
2.
3.
Ferrari Angela MD Lozzi Gian Piero MD Fargnoli Maria Concetta MD Peris Ketty MD 《Dermatologic surgery》2005,31(11):1448-1450
Background. A combined nevus most commonly consists of a blue nevus in combination with a Clark or Spitz nevus. Dermoscopically, combined nevus can mimic melanoma owing to the presence of dermoscopic features common to both types of lesions. Benign clinical and dermoscopic changes can occur in nevi over time, especially in children and young adults.
Objective. To describe the dermoscopic evolution of a congenital combined nevus showing unusual dermoscopic features.
Methods. Digital dermoscopic analysis was performed at the initial visit and after 8 months. The lesion was surgically excised and histopathologically examined.
Results. An asymptomatic plaque with a central blue area and peripheral brown pigmentation located on the back of a 13-year-old boy was diagnosed dermoscopically as combined nevus. Dermoscopic analysis 8 months later showed color changes from steel blue to gray-blue and black in the central area of the lesion, an increased number of blue-black dots or globules, and peripheral irregular streaks. Histopathology revealed typical features of a congenital combined nevus (blue nevus + compound nevus).
Conclusion. Over time, congenital combined nevus may show clinical and dermoscopic changes in size, color, and structure. Surgical excision is recommended when clinical and dermoscopic features are equivocal and the diagnosis of melanoma cannot be ruled out.
ANGELA FERRARI, MD, GIAN PIERO LOZZI, MD, MARIA CONCETTA FARGNOLI, MD, AND KETTY PERIS, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. 相似文献
Objective. To describe the dermoscopic evolution of a congenital combined nevus showing unusual dermoscopic features.
Methods. Digital dermoscopic analysis was performed at the initial visit and after 8 months. The lesion was surgically excised and histopathologically examined.
Results. An asymptomatic plaque with a central blue area and peripheral brown pigmentation located on the back of a 13-year-old boy was diagnosed dermoscopically as combined nevus. Dermoscopic analysis 8 months later showed color changes from steel blue to gray-blue and black in the central area of the lesion, an increased number of blue-black dots or globules, and peripheral irregular streaks. Histopathology revealed typical features of a congenital combined nevus (blue nevus + compound nevus).
Conclusion. Over time, congenital combined nevus may show clinical and dermoscopic changes in size, color, and structure. Surgical excision is recommended when clinical and dermoscopic features are equivocal and the diagnosis of melanoma cannot be ruled out.
ANGELA FERRARI, MD, GIAN PIERO LOZZI, MD, MARIA CONCETTA FARGNOLI, MD, AND KETTY PERIS, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. 相似文献
4.
Angelo Cagnacci Gian Benedetto Melis Renza Soldani Anna Maria Paoletti Marco Gambacciani Adriana Spinetti Piero Fioretti 《Maturitas》1991,13(4):283-296
The neuroendocrine and clinical effects of transdermal 17β-estradiol (rated at 50 μg/day; TTS 50) were studied in 40 postmenopausal women; ten additional postmenopausal women did not receive any drugs. The changes in LH and rectal temperature induced by the infusion of the opioid antagonist naloxone (10 mg i.v. bolus plus 10 mg/h for 4 h) were used to evaluate the central activity of endogenous opioid peptides. TTS 50 increased opioid activity, as evidenced by the restoration of the LH response (P < 0.01) and the enhancement of the hypothermic effect (P < 0.05) of naloxone. A greater reduction in hot flushes was observed in TTS 50-treated subjects than in untreated women, with the maximal effect of TTS 50 achieved after 3 months of therapy. TTS 50 did not modify the concentrations of circulating lipids, glucose or liver enzymes but reduced the biochemical parameters indicative of bone reabsorption. Bone density of the distal radius significantly increased during TTS 50 (P < 0.02), reaching its maximum value after 6 months of therapy. Thereafter bone density declined, but more slowly than in untreated women.
Our data suggest that TTS 50 has marked neuroendocrine effects, that it diminishes the incidence of hot flushes and reduces bone demineralization. By contrast, it has a very little, if any, metabolic impact on the liver or on glucose and lipid metabolism. 相似文献
5.
Luca Oscar Redaelli De Zinis Andrea Bolzoni Cesare Piazza Piero Nicolai 《European archives of oto-rhino-laryngology》2006,263(12):1131-1135
Lymph node (LN) metastases represent the most important negative prognostic factor in squamous cell carcinoma (SCC) of the oral cavity, even though controversies still exist regarding their management. The aim of this study was to retrospectively analyze our experience in surgical management of SCC of the oral cavity with particular focus on the prevalence and localization of lymph nodal metastases and recurrences. The clinical records of 89 consecutive patients treated from 1983 to 2002 by concomitant surgery on both the T and N sites, excluding those undergoing salvage surgery, were reviewed. A total of 119 neck dissections (ND) were performed. Survival outcomes were calculated by the Kaplan–Meier method, while univariate comparisons by the log-rank and non-parametric tests were performed between different groups of patients. Five-year overall and determinate survivals were 50 and 57%, respectively. LN metastases were observed in 52% (56% of these showing extracapsular spread) and their presence strongly correlated with determinate survival (p < 0.0001). The prevalence of clinical and occult nodal disease was not related to the pT status. Neck levels II (59%) and I (56%) were most frequently involved. Metastases to level IV accounted for 15% of positive LN, even though 28% of them turned out to be skip metastases. Five neck recurrences were observed, only one of which was salvaged by surgery. The high prevalence of clinical and occult LN metastases in this setting suggests that ND should be performed on a nearly routine basis, even for lesions with a low-T category and a cN0 neck. Moreover, ND should always encompass level IV due to the possibility of skip metastases, particularly in tumors involving the oral tongue. In patients with a cN+ neck, levels from I to V should be addressed, particularly in the presence of metastases at levels III and IV. 相似文献
6.
Hydrogen breath test for diagnosis of lactose malabsorption: the importance of timing and the number of breath samples. 总被引:2,自引:0,他引:2
Mauro Di Camillo Vanessa Marinaro Fiorenza Argnani Tiziana Foglietta Piero Vernia 《Journal canadien de gastroenterologie》2006,20(4):265-268
BACKGROUND: The hydrogen breath test (H(2)BT) is the most widely used procedure in the diagnostic workup of lactose malabsorption and lactose intolerance. AIM: To establish whether a simplified two- or three-sample test may reduce time, costs and staff resources without reducing the sensitivity of the procedure. PATIENTS AND METHODS: Data from 1,112 patients (292 men, 820 women) with a positive 4 h, nine-sample H(2)BT were retrospectively analyzed. Patients were stratified according to the degree of lactose malabsorption, the occurrence and type of symptoms. Loss of sensitivity in the procedure was evaluated taking into account two-sample tests (0 min and 120 min or 0 min and 210 min) or three-sample tests (0 min, 120 min and 180 min or 0 min, 120 min and 210 min). RESULTS: Using a two-sample test (0 min and 120 min or 0 min and 210 min) the false-negative rate was 33.4% and 22.7%, respectively. With a three-sample test (0 min, 120 min and 180 min or 0 min, 120 min or 210 min), lactose malabsorption was diagnosed in 91.2% (1,014 of 1,112) patients and in 96.1% (1,068 of 1,112) patients, respectively. Of 594 patients with abdominal symptoms, 158 (26.6%) and 73 (12.2%) would have false-negative results with 0 min and 120 min or 0 min and 210 min two-sample tests, respectively. The three-sample tests, 0 min, 120 min and 180 min or 0 min, 120 min and 210 min, have a false-negative rate of 5.9% and 2.1%, respectively. CONCLUSIONS: A three-sample H(2)BT is time- and cost-sparing without significant loss of sensitivity for the diagnosis both of lactose malabsorption and lactose intolerance. 相似文献
7.
P Pantano V Di Piero C Fieschi A Judica C Guariglia L Pizzamiglio 《The International journal of neuroscience》1992,66(3-4):153-161
The CBF was assessed in seven patients before and after rehabilitation for visuospatial neglect. Two months of treatment produced an increased perfusion both in the right posterior and left anterior areas of the brain. However, only the left anterior CBF increase was correlated with the neglect disorders. The left anterior improvement in CBF was inversely correlated with right-left cerebellum asymmetry in pre- and post-treatment. The present data suggest the role of the frontal eye-fields in the mechanism of recovery of visual exploration in patients with severe neglect. 相似文献
8.
Piero Volpi Luca Marinoni Corrado Bait Marco Galli Matteo Denti 《Knee surgery, sports traumatology, arthroscopy》2007,15(8):1028-1034
Lateral unicompartmental knee arthroplasty (UKA) is a valid alternative treatment in the event of arthritis confined to the
lateral compartment. This paper examines its indications, technique and short to medium-term results. A total of 159 Miller–Galante
cemented UKA prostheses (Zimmer, Warsaw, Indiana) were implanted consecutively (131 medial and 28 lateral) by the same surgeon.
This study investigates 28 lateral UKAs in 27 patients. Twenty-five implants in 24 patients (including a subject operated
bilaterally) were followed up for 12–60 months. Three patients were discarded on account of to short a follow-up period. The
Hospital for Special Surgery (HSS) knee score was used to compare the pre- and post-operative results of the lateral UKA patients.
The HSS score improved from a pre-op mean of 59.92 (range 48–68) to 88.04 (range 71–95) at the last follow-up. There was a
positive increase in the pain, function and ROM components of the score. The lateral UKA prosthesis can be regarded as a sound
alternative to total knee replacement. Correct patient selection on the basis of optimum surgical indications, however, is
essential.
No benefits of funds were received in support of the study. 相似文献
9.
Treatment of Hemorrhoids in Day Surgery: Stapled Hemorrhoidopexy vs Milligan–Morgan Hemorrhoidectomy
Vito Maria Stolfi Pierpaolo Sileri Chiara Micossi Isabella Carbonaro Marco Venza Paolo Gentileschi Piero Rossi Alessandro Falchetti Achille Gaspari 《Journal of gastrointestinal surgery》2008,12(5):795-801
Background Recently, it has been demonstrated that surgical treatment of hemorrhoids in a day-care basis is possible and safe. The aim
of this study was to compare the Longo stapled hemorrhoidopexy (SH) and the Milligan–Morgan hemorrhoidectomy (MMH).
Methods One hundred seventy one patients (95 cases in SH group and 76 cases in MMH group) entered the study: 83 cases were III degree
hemorrhoids, 88 IV degree. A priori and a post hoc power analysis were performed. Results, prospectively collected, were compared
using chi squared test and student t test. Visual analog scale was used for pain evaluation. Postoperative pain, duration of pain, wound secretion, bleeding,
resumption of a normal lifestyle, and postoperative complication were evaluated.
Results Surgical time was 28.41 ± 10.78 for MMH and 28.30 ± 13.28 min in SH (P = 0.94). Postoperative pain was not different between MMH and SH during the first two postoperative days (4.73 ± 2.91 vs
5.1 ± 3.048; P = 0.4), during the following 6 days, patients treated with SH had less pain (4.63 ± 2.04 in MMH vs 3.60 ± 2.35 in SH; P = 0.006). In the SH group, seven patients needed further hospital stay for complicated course. SH showed higher incidence
of anal fissure compared with MMH (6.3% vs 0%; P = 0.025) but no differences in urinary retention, anal stricture, urgency, or anal hemorrhage.
Conclusions This study confirms that SH is associated with less postoperative pain and shorter postoperative symptoms, compared with MMH.
SH may be a viable addition to the therapy for hemorrhoids with some advantages in early postoperative pain and some disadvantages
in postoperative complications and costs. 相似文献
10.