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781.
BACKGROUND: Although mouse allergen is known to cause occupational asthma in laboratory workers, its potential significance in home environments has never been studied. OBJECTIVE: This study was designed to define the prevalence of mouse sensitivity and its relationship to mouse allergen exposure and disease activity in inner-city children with asthma. METHODS: A subset of 499 subjects from the National Cooperative Inner-City Asthma Study had dust samples adequate for mouse allergen analysis, as well as valid puncture skin test (PST) results. Data were analyzed to relate mouse allergen exposure and other risk factors to mouse sensitization and asthma morbidity. RESULTS: Eighty-nine (18%) of the 499 children had a positive mouse skin test response. Children whose homes had mouse allergen levels above the median (1.60 microg/g) in the kitchen had a significantly higher rate of mouse sensitization (23% vs 11%, P =. 007). Atopy was also significantly related to mouse sensitization, with 40% of those with more than 4 positive PST responses having mouse sensitivity compared with 4% of those with no other positive PST responses (P <.0001). When atopy and exposure were considered together, 53% of those with more than 4 positive PST responses and allergen levels above the median had a positive PST response to mouse allergen compared with 22% of those with more than 4 positive PST responses and allergen levels below the median (P <.0001). The relationship among mouse allergen exposure, sensitization, and any measures of asthma morbidity was not statistically significant. CONCLUSIONS: Mouse allergen may be an important indoor allergen in inner-city children with asthma, with exposure and atopy contributing to mouse sensitization.  相似文献   
782.
A papillomavirus antigen has been identified in tissue sections of laryngeal papillomata removed at endoscopic operations. The demonstration of the papillomavirus antigen was achieved using the peroxidase-anti-peroxidase test of Sternberger after a broadly cross-reactive rabbit antiserum to the papillomavirus capsid antigen was incubated with the tissue sections. The antigen was detected in specimens from 7 of 15 patients with juvenile-onset laryngeal papillomas, but could not be demonstrated in the specimens from 6 patients with adult-onset papillomas. In all, 73 biopsy specimens from 21 patients were selected for study; 18% (11/61) of the sections from the juvenile-onset patients and 0% (0/12) of the sections from the adult-onset patient specimens exhibited the papillomavirus antigen. The presence of the virus antigen did not correlate with the stage of disease, nor with the duration or severity of the illness. The implications of the findings are discussed.  相似文献   
783.
Desmoid tumors are locally invasive fibrous neoplasms that arise from musculoaponeurotic structures. We report the first case of a desmoid tumor of the larynx complicating pregnancy. At 21 weeks' gestation fiberoptic and indirect otolaryngologic examination of the patient's larynx revealed a submucosal tumor involving the left true vocal cord, ventricle of the larynx, and false vocal cord. Histopathologic examination revealed areas of extensive fibrosis intermixed with degenerated vocal cord skeletal muscle. Despite a subtotal excisional biopsy, growth of the desmoid tumor continued during pregnancy. Endoscopic evaluation 9 weeks post partum revealed complete regression of the tumor.  相似文献   
784.
Introduction of bacteria into the amniotic cavity has been associated with oral sex through an ascending infectious route. Previous reports have implicated both Capnocytophaga and Fusobacterium nucleatum via this process. We report a case of Streptococcus viridans intra-amniotic infection occurring at 25 weeks' gestation. Patient questioning revealed a close temporal relationship between the onset of symptoms and previous episodes of cunnilingus. The diagnosis of subclinical bacterial colonization of the amniotic fluid should be considered in patients presenting with preterm labour and no apparent aetiology. A history of recent cunnilingus may be associated with the presence of Streptococcus viridans in the amniotic fluid.  相似文献   
785.
BACKGROUND: Enterovesical fistula is a rare cause of recurrent urinary tract infections. This condition is unusual in young people as common etiologies include diverticular disease and cancer. When an enterovesical fistula occurs in women of childbearing age, Crohn's disease is a likely cause. To our knowledge, enterovesical fistula complicating pregnancy has not been reported before. CASE: A pregnant woman with recurrent urinary tract infections was evaluated. Cystoscopy was suggestive of an enterovesical fistula, which was confirmed by charcoaluria following oral charcoal administration. The prenatal course was complicated by two episodes of hemorrhagic cystitis despite antibiotic prophylaxis. The patient had an uncomplicated term spontaneous vaginal delivery. An upper gastrointestinal series performed postpartum was suggestive of Crohn's disease and confirmed an enterovesical fistula. Surgical repair was successfully performed three months following delivery, revealing Crohn's disease. CONCLUSION: Enterovesical fistula may be an unusual cause of recurrent urinary tract infections in pregnancy. In this case, enterovesical fistula was the presenting symptom of Crohn's disease.  相似文献   
786.
The node, or its zebrafish equivalent, Kupffers Vesicle (KV), is thought to generate laterality cues through cilia-dependent signaling. An interaction between Nodal ligands and Nodal antagonists around the node/KV is also required. Here we investigate whether loss of Brachyury/Notail or Tbx16/Spadetail disrupts the balance of Nodal ligands (Southpaw) and antagonists (Charon) around Kupffers Vesicle. Reduction of Spadetail or Notail disrupts expression of southpaw in the perinodal domains flanking Kupffers Vesicle. Similar to what was published for Notail, we find Spadetail is also required for expression of charon. We present evidence for the model that Notail has a direct role in regulating the charon promoter. In particular, a flanking genomic region with putative Notail binding sites can drive KV expression of a reporter in a Notail-dependent fashion. This region also contains motifs for CSL/RBP-J/Su(H). Consistent with this, we find charon expression is strongly Notch-dependent whereas perinodal southpaw expression is not.  相似文献   
787.
The primary tumors and metastases from 30 patients with stage II breast carcinoma treated with low- or standard-dose combination chemotherapy (cyclophosphamide, methotrexate, 5-fluorouracil) were studied by the immunoperoxidase technique for pregnancy-associated plasma protein A (PAPP-A), pregnancy-specific beta-1-glycoprotein (SP-1), and placental protein five (PP-5). In addition to immunostaining, 25 traditional clinicopathologic features were assessed with respect to early (at less than two years) recurrence. Of the 11 patients with early recurrences, nine (82 per cent) were PAPP-A-positive, while 16 of the 19 patients without early recurrences (84 per cent) were PAPP-A-negative (P less than 0.0005). None of the other clinicopathologic features correlated with early recurrence. Immunostaining for PAPP-A is thus a clinically significant predictor of early recurrence in patients with stage II breast carcinoma.  相似文献   
788.
We have used assays for histamine and for the specific mast cell enzyme, tryptase, to examine the response of the nasal mucosa to provocation with several different stimuli and to evaluate the reliability of histamine as a marker of mast cell activation. High levels of histamine detected in baseline lavages of some subjects are not associated with any detectable tryptase, suggesting they are not mast cell derived. During pronounced immediate allergic responses, however, mast cell degranulation clearly occurs, and a striking correlation between histamine and tryptase is observed. This correlation is weaker when a more modest allergic response is induced, possibly reflecting differential diffusion of the two mediators across the epithelium. Provocation of susceptible individuals with cold, dry air leads to increased recoveries of both histamine and tryptase, confirming that mast cell degranulation occurs during this reaction. Although hyperosmolarity of the nasal mucosa may contribute to mast cell degranulation induced by cold, dry air, a brief exposure of the nasal cavity to hyperosmolar mannitol was not associated with measurable production of tryptase. The combined use of histamine and tryptase measurements can therefore provide useful evidence regarding the role of mast cell activation in the pathogenesis of inflammatory responses.  相似文献   
789.
With monoclonal antibody D-274, raised against guinea pig milk fat globule membrane, the distribution of mucinlike glycoproteins of Mrs greater than or equal to 400,000 was determined in benign fibrocystic disease and infiltrating duct carcinoma of the human breast. These glycoproteins, called collectively PAS-I, were detected in 19 out of 20 cases of benign fibrocystic disease and in at least 26 out of 47 cases of infiltrating duct carcinoma. PAS-I was concentrated on luminal surfaces of ducts and alveoli in morphologically differentiated regions of the tumors. In areas where the glandular nature of the tissue was less evident in infiltrating duct carcinoma, the PAS-I determinant recognized by antibody D-274 was present on irregular luminal surfaces and in the cytoplasm. There was a negative correlation between the short-term recurrence (less than 2 years) of infiltrating duct carcinoma and the detection of strong positive staining with antibody D-274. The results are discussed with reference to recent studies on PAS-I in human breast tissue using monoclonal antibodies raised against human milk fat globule membrane.  相似文献   
790.
BACKGROUND: Exposure to mouse allergen is prevalent in inner-city homes and is associated with an increased risk of mouse skin test sensitivity in inner-city children with asthma. OBJECTIVE: To determine the distribution of mouse allergen and its relationship to mouse skin test sensitivity in a primarily suburban, middle-class population of asthmatic children. METHODS: Children with asthma, 6 to 17 years old, were recruited from 3 pediatric practices located in counties surrounding the city of Baltimore and from 1 practice located within the city limits. Participants underwent skin prick testing and completed a baseline questionnaire. Their homes were inspected, and settled dust samples were collected for allergen analysis. RESULTS: Two hundred fifty-seven of 335 (76.7%) participants resided outside the city, and 53.7% had annual incomes >$50,000. Mouse allergen was detected in 74.9% of bedrooms, and 13.1% were sensitized to mouse. Lower maternal education (odds ratio [OR], 2.17; 95% CI, 1.28-3.67), city residence (OR, 5.39; 95% CI, 2.23-13.02), and higher bedroom cockroach allergen levels (OR, 9.61; 95% CI, 1.17-79.03) were independent predictors of high bedroom mouse allergen. The risk of mouse skin test sensitivity increased with increasing bedroom Mus m 1 exposure (OR, 1.43; 95% CI, 1.04-1.96, with each increase in quartile), and dog skin test sensitivity was a strong independent predictor of mouse skin test sensitivity (OR, 7.23; 95% CI, 3.03-17.22). CONCLUSION: Mouse allergen exposure is common among suburban, middle-class asthmatic children. Increasing bedroom levels of Mus m 1 and dog skin test sensitivity are risk factors for mouse skin test sensitivity.  相似文献   
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