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991.
Limited data in children with cystic fibrosis (CF) suggest that respiratory viral infections during infancy result in substantial morbidity. Eighty of 101 (79%) infants with CF diagnosed by neonatal screening during 1991–1996 were recruited into a prospective, multiple-birth cohort study. We aimed to perform an initial, then annual bronchoalveolar lavage (BAL) for bacterial and viral culture, cytology, IL-8, and elastolytic activity over the following 2 years. When possible, BAL was also performed during any hospitalization for a pulmonary exacerbation, and additional specimens for viral culture were collected by nasopharyngeal aspiration. Thirteen infants undergoing bronchoscopy for congenital stridor served as disease controls. During infancy, 31 children (39%) were hospitalized for respiratory disease and 20 (65%) cases had an etiologic agent identified. Respiratory viruses were detected in 16/31 (52%) cases, including four with simultaneous bacterial infection. Another four were infected with Staphylococcus aureus. Respiratory syncytial virus predominated and was found in seven infants. In the absence of bacteria, those with viral infections had acute onset of respiratory distress, were not treated with antibiotics, and had an uncomplicated hospital course. Compared to noninfected CF subjects and controls, infected infants had elevated BAL inflammatory indices (P < 0.01). Eleven of 31 (35%) hospitalized infants followed for 12–60 months acquired Pseudomonas aeruginosa, compared with only three of 49 (6%) subjects not hospitalized for respiratory symptoms during infancy (risk ratio 5.8, CI 1.9, 24). We conclude that respiratory viruses are important causes of hospitalization in CF infants. While viral infections were self-limited, they were accompanied by airway inflammatory changes, and admission to hospital was associated with early acquisition of Pseudomonas aeruginosa and persistent respiratory symptoms. Pediatr Pulmonol. 1998; 26:371–379. © 1998 Wiley-Liss, Inc.  相似文献   
992.
993.
Ultrafast computed tomography (CT) can be performed in almost all children with little or no sedation. The benefit has to be balanced against financial cost and radiation dose. Since observing a steady increase in numbers of scans performed, we analyzed the contribution to management of 106 pediatric chest CT scans performed over a 12-month period. Forty-eight of 106 yielded a positive diagnosis and a further 43/106 provided clearly useful information. CT was most useful in children with chronic productive cough (21/48 scans showed bronchiectasis) and suspected interstitial lung disease. It was least useful in the preoperative assessment of empyema complicating community-acquired pneumonia (0/11 scans giving information that changed management). We conclude that the increased ease of performance of chest CT in children has not led to a large number of inappropriate requests. In the large majority of cases, diagnostically useful information was provided. Pediatr Pulmonol. 1998; 26:389–395. © 1998 Wiley-Liss, Inc.  相似文献   
994.
995.
We report on the unprecedented combination of two recessively inherited disorders, the kyphoscoliosis type of Ehlers-Danlos syndrome (EDS type VI) and cystic fibrosis (CF), in two sibs born to consanguineous Turkish parents. Because of failure to thrive and bronchitis CF was diagnosed in the index patient early whereas EDS VI was recognized only very late. Both patients had marked muscular hypotonia at birth, delayed gross motor development, progressive kyphoscoliosis, joint dislocations, Marfanoid habitus, hypertrophic and atrophic scars, and osteopenia. EDS VI was proven by collagen studies and the pathognomonic pattern of urinary pyridinolines. Because the genes coding for the two disorders are located on different chromosomes and a chromosomal rearrangement was excluded, we conclude that their combination is a chance association. The cardiopulmonary impairment common to both diseases makes the prognosis dismal. Am. J. Med. Genet. 78: 455–460, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
996.
The aims of this study are to depict the special but constant cytomorphologic features which allow a distinction among grossly similar skin tumors and to show that cytological assessment of many uncommon skin lesions is possible. The fine-needle aspiration findings of 181 cytologically interesting cases of primary skin tumors selected from 2,301 primary skin lesions examined in our department from 1990–1995 are described. Seventy-five cases were cytologically reported as benign and 89 as malignant. In 17 cases the aspirated material was considered inconclusive, although some possible diagnoses could be supported. A subsequent histological examination followed the cytologic assessment in all cases. Fine-needle aspiration cytology identified uncommon cutaneous cystic lesions (bronchogenic, dermoid, myxoid), benign and malignant tumors of epidermal appendages such as chondroid syringomas, cylindromas, pilomatrixomas, sebaceous carcinoma, and primary adenoid cystic carcinoma, as well as tumors of the dermis and subcutaneous fat. Primary cutaneous lymphomas were also diagnosed and classified morphologically and immunocytochemically. In our diagnoses of uncommon skin tumors new cytologic criteria were created and utilized and are described in this report in detail. Diagn. Cytopathol. 1998;19:17–28. © 1998 Wiley-Liss, Inc.  相似文献   
997.
We report the case of a male newborn infant with an intra-abdominal cavernous lymphangioma that produced acute abdominal symptoms. Sonography showed a cystic mass with thin septations, which caused intestinal obstruction and stenosis of the iliac artery. The histologic findings after surgical resection reflected the sonographic appearance of the mass. The differential diagnosis of cystic abdominal lesions is discussed. Sonography is the preferred method of diagnosis. © 1998 John Wiley & Sons, Inc. J Clin Ultrasound 26:320–322, 1998.  相似文献   
998.
999.
More than 500 mutations have been identified in the CFTR gene, making it an excellent system for testing mutation scanning techniques. To assess the sensitivity of denaturing gradient gel electrophoresis (DGGE), we collected a representative group of 202 CFTR mutations. All mutations analyzed were detected by scanning methods other than the DGGE approach evaluated in this study. DGGE analysis was performed on 24 of the 27 exons and their flanking splice site sequences. After optimization, 201 of the 202 control samples produced an altered migration pattern in the region in which an alteration occurred. The remaining sample was sequenced and found not to have the reported mutation. The ability of DGGE to identify novel mutations was evaluated in three Asian CF patients with four unknown CF alleles. Three novel Asian mutations were detected—K166E, L568X, and 3121-2 A→G (in homozygosity)—accounting for all CF alleles. These results indicate that an optimized DGGE scanning strategy is highly sensitive and specific and can detect 100% of mutations. Hum Mutat 9:136–147, l997. © 1997 Wiley-Liss, Inc.  相似文献   
1000.
Forty-two histologically confirmed cases of pancreatic cystic lesions with cytologic evaluation by needle aspiration biopsy (NAB) were reviewed. There were 21 inflammatory pseudocysts (IPC), nine mucinous cystic neoplasms (MCN), six microcystic serous adenomas (MSA), one macrocystic serous adenoma, and five papillary solid and cystic neoplasms (PSCN). Correct cytodiagnosis was made in all cases of IPC and MCN. The contents of IPCs were characterized by turbid or blood-tinged fluid containing cellular debris, numerous foamy macrophages, and other inflammatory cells. There were few or no epithelial lining cells. The aspirates from MCNs showed gelatinous mucoid material containing mucus-secreting cells that were present singly, in clusters, or in sheets. Depending on the individual case, benign or malignant columnar cells, or an admixture of these cells, were present in a mucinous background. The preoperative needle aspirates of five MSAs were acellular. In one case of MSA and in one example of macrocystic serous adenoma, small monolayered sheets of benign cubic epithelial cells were seen in the needle aspirates. Similar cytologic findings were noted in the materials obtained by intraoperative NAB performed under direct vision of the aforementioned five MSAs. Difficulties were encountered in typing three PSCNs that yielded in NAB cells resembling those of an islet cell tumor. They were diagnosed as low-grade neoplasms (PSCN vs. islet cell tumor). In two other patients, a cytodiagnosis of PSCN was correctly made as the NAB revealed monomorphic tumor cells wrapping around small capillary blood vessels. Diagn. Cytopathol. 1997;17:177–182. © 1997 Wiley-Liss, Inc.  相似文献   
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