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81.
Teeth with white spot lesions (WSL) might be more prone to enamel loss during bracket debonding. This in vitro study compared enamel loss from teeth with (n = 14) and without (n = 14) WSL after polishing with low-speed finishing burs or disks (Sof-Lex, 3M ESPE, St Paul, Minn). Debonded surfaces were analyzed with a contact stylus profilometer, and digitized data were compared with baseline readings by using AnSur NT software (Regents, University of Minnesota, Minneapolis, Minn). Specimen surfaces were also examined with a scanning electron microscope. Two-way analysis of variance was performed to analyze the data. In teeth without WSL, the volume losses were 0.16 mm(3) for the bur group and 0.10 mm(3) for the disk group; the mean maximum depths were 47.7 microm for the bur group and 54.3 microm for the disk group. In teeth with WSL, the volume losses were 0.06 and 0.17 mm(3), and the mean maximum depths were 35.1 and 48.7 microm for the bur and disk groups, respectively. There were no significant differences in enamel loss between the 2 groups of teeth without WSL (P =.12). However, in teeth with WSL, the burs removed less enamel than the disks (P = 0.006). Scanning electron microscope examination showed that any damage on the enamel surface was usually located in the cervical third of the teeth. On most specimens, even though tooth surfaces appeared resin-free to the naked eye, there were remnants of it. The differences between groups were so small that they might be clinically insignificant.  相似文献   
82.
PURPOSE: To present a case of laryngeal damage in an infant caused by a too large and inappropriately designed cuffed tracheal tube. CLINICAL FEATURES: A 13-month-old child undergoing cardiac surgery was intubated with an uncuffed endotracheal tube with an internal diameter (ID) of 4.0 mm. Because of an important air leak around the tracheal tube during mechanical ventilation, a cuffed endotracheal tube ID 4.0 mm was inserted. The air leak with the tube cuff not inflated was acceptable at 25 cm H2O airway pressure. After extubation on the third postoperative day, the patient showed increasing stridor and respiratory deterioration. Fibreoptic laryngoscopy of the spontaneously breathing patient showed a large intra-laryngeal web. After surgical removal of the web, the child rapidly recovered and was discharged from the hospital on the 12th postoperative day. Inspection of the 4.0 mm (ID) cuffed tracheal tube revealed a cuff positioned inappropriately high and an increase of 0.7 mm in outer tube diameter compared to the 4.0 mm (ID) uncuffed tracheal tube from the same manufacturer. The tube cuff is likely to be situated within the larynx when placed in accordance to insertion depth formulas or radiological criteria, as used for uncuffed tracheal tubes in children. CONCLUSION: The larger than expected tracheal tube with its intra-laryngeal cuff position in a 13-month-old child likely caused mucosal damage and an inflammatory reaction within the larynx resulting in granulation tissue formation and fibrous healing around the tracheal tube.  相似文献   
83.
Laparoscopic Heller myotomy (LHM) has become the standard treatment option for achalasia. The incidence of esophageal perforation reported is about 5%–10%. Robotically assisted Heller myotomy (RAHM) is emerging as a safe alternative to LHM. Data comparing the two approaches are scant. The aim of this study was to compare RAHM with LHM in terms of efficacy and safety for treatment of achalasia. A total of 121 patients underwent surgical treatment of achalasia at three institutions. A retrospective review of prospectively collected perioperative data was performed. Patients were divided into two groups: group A (RAHM), 59 patients, and group B (LHM), 62 patients. All the operations were completed using minimally invasive techniques. There were 63 women and 58 men, with a mean age of 45 ±19 years (14–82 years). Fifty-one percent of patients in group A and 95% of patients in group B reported weight loss. Duration of symptoms was equal for both groups. Dysphagia was the main complaint in both groups (P = NS). There was no difference in preoperative endoscopic treatment in both groups (44% versus 27%, P = NS). Operative time was significantly shorter for LHM in the first half of the experience (141 ± 49 versus 122 ± 44 minutes, P < .05). However, in the last 30 cases there was no difference in operative time between the groups (P = NS). Intraoperative complications (esophageal perforation) were more frequent in group B (16% versus 0%). The incidence of postoperative heartburn did not differ by group. There were no deaths. At 18 and 22 months, 92% and 90% of patients had relief of their dysphagia. This study suggests that RAHM is safer than LHM, because it decreases the incidence of esophageal perforation to 0%, even in patients who had previous treatment. At short-term follow-up, relief of dysphagia was equally achieved in both groups. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation). This study was supported in part by a grant provided by Intuitive Surgical, Inc. and Ethicon Endo-Surgery, Inc.  相似文献   
84.
Forty consecutive adult patients under the age of 50 with acute non-lymphoblastic leukemia (ANLL) in first complete remission, underwent autologous bone marrow transplantation (ABMT) between March 1984 and April 1990. The conditioning regimen employed included cyclophosphamide and total body irradiation, followed by the administration of unpurged ABMT. The median time from diagnosis to transplant was 7 months (3-15 months), and the median time from complete remission to ABMT was 4 months (range 3-9 months). Twenty-two (51%) patients remain in complete remission 6-81 months (median 24 months) after ABMT.

The causes of death were, recurrent leukemia (11 patients), parenchymal toxicities such as acute respiratory distress syndrome and veno-occlusive disease (3 patients), hemorrhage (2 patients) and infection (2 patients). Eleven patients relapsed after 3-12 months (median 5 months). This study has produced survival data comparable to those of other institutions employing TBI for either allo or autotransplants.  相似文献   
85.
We demonstrate that a mixture of four recombinant dengue virus E polypeptides corresponding to the N-terminal region of the envelope protein from all serotypes substitutes for standard antigens in two immunoglobulin M enzyme-linked immunosorbent assay formats with 100% concordance, making these polypeptides a useful and accessible reagent for serological diagnosis of dengue in endemic countries.  相似文献   
86.
The purpose of the present study was to investigate the influence of different drugs exhibiting different solubility on the viscoelastic properties and on the skin diffusion profile of a ringing gel. In a preliminary rheology study with the placebo gel predominating elastic properties were confirmed and a temperature influence was indicated. Fluconazole, fludrocortisone-acetate, flumethasone-pivalate, flutamide and flufenamic-acid each 1% (w/w) were incorporated into the preparation and oscillatory measurements were performed at temperatures of 25, 28, 32 and 37 degrees C. In all drug containing formulations a high elastic G' value predominated the viscous G' value. The highest G' value could be obtained with the incorporated flumethasone-pivalate. Additionally in almost all cases the G' values decreased with increasing temperature compared to the placebo gel. Additionally in vitro standard diffusion experiments using Franz-type cells and porcine skin were performed. Following rank order of the cumulative drug release after 48 h was obtained: fluconazole>flufenamic-acid>flumethasone-pivalate>flutamide>fludrocortisone-acetate. Furthermore an excellent chemical stability of all incorporated drugs was confirmed over 10 weeks.  相似文献   
87.
ReProComet: a new in vitro method to assess DNA damage in mammalian sperm.   总被引:1,自引:0,他引:1  
The increasing request of chemical safety assessment demands for the validation of alternative methods to reduce the resort to animal experimentation. Methods that evaluate reproductive toxicity are among those requiring the largest use of animals. Presently, no validated in vitro alternative exists for the assessment of reproductive toxicity. Mammalian sperm are sensitive targets of DNA-reactive chemicals, which form premutagenic adducts. Here, we propose a new method based on comet assay to detect DNA damage induced by potential germ cell mutagens in bull sperm available from assisted reproduction practices. In somatic cells, chemical-induced adducts can be revealed by comet assay that detects DNA breaks produced during adduct repair. Mature sperm, however, are devoid of repair enzymes, and adducts are processed only after fertilization. For this reason, comet assay is not sensitive to detect DNA lesions induced in sperm by most chemicals. To overcome such limitation, we developed a modified comet assay based on the addition of a protein extract from HeLa cells to agarose-embedded sperm on microscopic slides. To test the method, sperm were treated in vitro with methyl methanesulfonate (MMS) or melphalan (MLP) and comet assay was conducted both with and without protein supplementation. No effect of MMS or MLP was detected without protein supplementation; on the contrary, a clear-cut dose-dependent effect was measured after addition of the cell extract. These results represent a proof of concept of a novel in vitro mutagenicity test on sperm that could offer a promising approach to complement previously validated in vivo germ cell genotoxicity assays.  相似文献   
88.
AIM: To gain insight into the impact of urinary incontinence on the daily lives of Moroccan and Turkish women and their preferences for treatment. DESIGN OF STUDY: A qualitative analysis of data from semi-structured in depth interviews with 30 Moroccan and Turkish migrant women with urinary incontinence. SETTING: Six general practices with large numbers of immigrant families in four cities in the Netherlands. METHOD: Semi-structured in depth interviews were conducted with Moroccan and Turkish migrant women, who presented with complaints of urinary incontinence in six general practices with large numbers of immigrant families on the practice list in four different cities in the Netherlands. RESULTS: All the women adhered closely to bodily cleanliness and considered incontinence to be dirty. As Muslims, they were obliged to perform ritual prayers preceded by ablution five times per day and the urinary incontinence breached their status of ritual purity. Therefore, they had to wash more often and experienced this as a heavy burden. In a number of the women, shame formed a reason why they could not talk to anybody about the incontinence, not even with the doctor. One-third of the women felt that their GP had not taken them seriously. Knowledge about anatomy, physiology and available treatments was mostly lacking. In addition, the women did not understand the aim of the exercises from the physiotherapist. The majority of women gave preference to help from a female doctor. CONCLUSION: Urinary incontinence in Moroccan and Turkish migrant women formed a considerable problem in their daily following of the Islam faith. Shame on the part of the patient and miscommunication at the doctor's surgery led to inadequate care.  相似文献   
89.
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   
90.
This study investigates whether tissue recoil or patient intrinsic factors influence the final position of the nipple areola complex (NAC) after reduction mammoplasty. The age, pre-operative ptosis, BMI and weight of the tissue resected were recorded as patient intrinsic factors in 37 patients undergoing reduction mammoplasty. The “spring-back” value was defined as the distance from the sternal notch to a nipple landmark on the breast meridian with the patient sitting up, minus the same measurement repeated with the patient recumbent to eliminate the pull of gravity on the breast. Spring back was measured pre-operatively for the nipple and nipple mark then post-operative for the nipple. The difference in centimeters between the final post-operative distance from the sternal notch to the nipple and the level intended by the pre-operative nipple mark was termed the “judgment error.” The final position of the post-operative nipple and the judgment error was compared to the spring-back values and patient intrinsic factors. Pre-operative ptosis was statistically related to increasing patient BMI and mass of tissue resected per breast. Pre-operative spring-back values for the nipple increased with increasing ptosis, BMI and decreasing age. Spring-back values were greater in the lower pole of the breast than in the upper pole. The final position of the nipple was higher than the pre-operative mark in 65% of cases, lower in 8% and as marked in 27% of cases. The post-operative NAC was, on average, 0.6 cm higher than planned pre-operatively. The post-operative distance from the sternal notch to the nipple increased with increasing pre-operative ptosis, mass of breast tissue resected per breast and all three spring-back values. The difference between the level of the pre-operative mark and the final nipple position showed a weak correlation with post-operative spring-back values. The parameters of ptosis, BMI, weight of tissue resected per breast and pre-operative nipple spring back reflect body habitus and breast size. Spring-back values vary between the upper and lower pole of the breast. The final NAC position was higher than that intended at pre-operative marking in the majority of cases. The surgeon instinctively marks the nipple lower in patients with greater pre-operative ptosis and in whom a larger resection is anticipated. Judgment error did not relate to intrinsic factors nor to pre-operative spring-back values; hence, these parameters cannot be applied as predictive tools for more accurate pre-operative marking of the nipple position. This study suggests that the pre-operative nipple mark should be placed, with the patient sitting up, at least 23 cm from the sternal notch and 0.6 cm lower than the final position estimated using the inframammary crease as a landmark. An invited commentary on this paper is available at .  相似文献   
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