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121.
A defective Vkappa A2 allele in Navajos which may play a role in increased susceptibility to haemophilus influenzae type b disease. 总被引:1,自引:0,他引:1 下载免费PDF全文
A J Feeney M J Atkinson M J Cowan G Escuro G Lugo 《The Journal of clinical investigation》1996,97(10):2277-2282
The antibody response to H. influenzae type b (Hib) is pauciclonal, and is dominated by antibodies using the VkappaA2 gene. Navajos have a 5-10-fold increased incidence of Hib disease compared with control populations. We hypothesized that a polymorphism in one of the genes in this oligoclonal response may lead to increased disease susceptibility. Since the predominant A2+ anti-Hib antibodies have high avidity for Hib and can be unmutated, the A2 Vkappa gene was analyzed. Over half of the Navajos studied, but only one control individual, had a new allele of A2, termed A2b, with three changes from the published A2 germline sequence. One of the changes was in the recombination signal sequence, suggesting that the A2b allele might not undergo V-J rearrangement very frequently. This possibility was confirmed by analyzing the relative frequency of non-productive A2 rearrangements in A2a/b heterozygous Navajos. Many fewer A2b rearrangements were observed, showing that the A2b allele is defective in its ability to undergo rearrangement. The prevalence of this allele in Navajos may play a role in their increased susceptibility to invasive Hib disease. If so, it would underscore the importance of the germline Ig repertoire for protective antibody responses to pathogenic bacteria in unimmunized children. 相似文献
122.
L Willocks F Cowan R P Brettle F X Emmanuel P J Flegg S Burns 《The Journal of infection》1992,24(1):37-42
In a retrospective analysis of all known HIV-positive patients admitted to the City Hospital before November 1989, 208 patients accounted for 612 admissions, 72% being injection drug users (IDUs). One hundred and eighty admissions (29%) were for chest-related disorders, and this was the commonest reason for admission. Unlike other U.K. centres where more than 50% chest problems are due to Pneumocystis carinii pneumonia (PCP), only 27% of our chest admissions were for PCP. Fifty-four percent of chest admissions were for bacterial chest infections (BCIs), the commonest organism isolated being Haemophilus influenzae. Despite the fact that most (50/97) of these admissions were in patients with 'asymptomatic' HIV disease (CDC classification 2 and 3), 50% had radiological pneumonia, 43% were hypoxic, 28% were hypercapnic and the average duration of hospitalisation was 10 days. BCIs were more common in HIV-positive IDUs when compared with HIV-negative IDUs, other HIV-positive patients and the general age-matched population. Medical provision for IDU-related HIV disease should take into account the high rate of BCIs and of hospital admissions in patients who do not yet have CDC stage 4 disease. 相似文献
123.
Jennifer M. Rudd Miruthula Tamil Selvan Shannon Cowan Yun-Fan Kao Cecily C. Midkiff Sai Narayanan Akhilesh Ramachandran Jerry W. Ritchey Craig A. Miller 《Viruses》2021,13(8)
The emergence and ensuing dominance of COVID-19 on the world stage has emphasized the urgency of efficient animal models for the development of therapeutics for and assessment of immune responses to SARS-CoV-2 infection. Shortcomings of current animal models for SARS-CoV-2 include limited lower respiratory disease, divergence from clinical COVID-19 disease, and requirements for host genetic modifications to permit infection. In this study, n = 12 specific-pathogen-free domestic cats were infected intratracheally with SARS-CoV-2 to evaluate clinical disease, histopathologic lesions, and viral infection kinetics at 4 and 8 days post-inoculation; n = 6 sham-inoculated cats served as controls. Intratracheal inoculation of SARS-CoV-2 produced a significant degree of clinical disease (lethargy, fever, dyspnea, and dry cough) consistent with that observed in the early exudative phase of COVID-19. Pulmonary lesions such as diffuse alveolar damage, hyaline membrane formation, fibrin deposition, and proteinaceous exudates were also observed with SARS-CoV-2 infection, replicating lesions identified in people hospitalized with ARDS from COVID-19. A significant correlation was observed between the degree of clinical disease identified in infected cats and pulmonary lesions. Viral loads and ACE2 expression were also quantified in nasal turbinates, distal trachea, lungs, and other organs. Results of this study validate a feline model for SARS-CoV-2 infection that results in clinical disease and histopathologic lesions consistent with acute COVID-19 in humans, thus encouraging its use for future translational studies. 相似文献
124.
Arnold Danielle E. Chellapandian Deepak Parikh Suhag Mallhi Kanwaldeep Marsh Rebecca A. Heimall Jennifer R. Grossman Debra Chitty-Lopez Maria Murguia-Favela Luis Gennery Andrew R. Boulad Farid Arbuckle Erin Cowan Morton J. Dvorak Christopher C. Griffith Linda M. Haddad Elie Kohn Donald B. Notarangelo Luigi D. Pai Sung-Yun Puck Jennifer M. Pulsipher Michael A. Torgerson Troy Kang Elizabeth M. Malech Harry L. Leiding Jennifer W. 《Journal of clinical immunology》2022,42(5):1026-1035
Journal of Clinical Immunology - Granulocyte transfusions are sometimes used as adjunctive therapy for the treatment of infection in patients with chronic granulomatous disease (CGD). However,... 相似文献
125.
126.
Detection of Human T-Lymphotropic Virus (HTLV) tax Sequences in New York City Blood Donors Seronegative for HTLV Types 1 and 2 下载免费PDF全文
Charlene S. Dezzutti Patricia C. Guenthner Sylvester Daniel Ursula Utz Thania Cabrera James H. Marshall Celso Bianco Renu B. Lal Elliot P. Cowan 《Clinical and Vaccine Immunology : CVI》2003,10(4):715-717
A potential public health concern is the reported detection of the human T-lymphotropic virus (HTLV) tax gene in the lymphocytes of up to 11% of a low-risk group of New York City blood donors (NYBD). This study aimed to independently confirm the prevalence of HTLV tax sequences in 293 NYBD. All NYBD tested negative for antibodies to HTLV types 1 and 2 and HTLV Tax. HTLV tax sequences were not detected in the NYBD lymphocytes. These data demonstrate the lack of HTLV-1 tax in this group of NYBD at low risk for HTLV infection. 相似文献
127.
Yimin Ge Mario A. Luna Daniel F. Cowan Luan D. Truong Alberto G. Ayala 《Annals of diagnostic pathology》2009,13(6):384-389
Because thyrolipoma (adenolipoma of thyroid) and thyrolipomatosis (diffuse lipomatosis of thyroid) are distinctively rare conditions with only few cases reported in the literature, we are reporting 5 additional cases. All the 5 patients were adult females, with ages from 38 to 79 years, who presented with thyroid masses. Four of the patients had normal thyroid function tests and one had mild hypothyroidism. All patients received partial or total thyroidectomy. The thyroid specimens showed either circumscribed yellow-tan masses (cases 1, 2, and 3) or diffuse yellow-brown discoloration (cases 4 and 5). Histologic examination revealed abundant mature fat infiltrating the affected thyroid tissue in 3 distinct patterns: (1) fat infiltration limited to follicular adenomas (thyrolipoma); (2) fat diffusely infiltrating throughout the thyroid gland (thyrolipomatosis); or (3) fat infiltration involving both follicular adenoma and their surrounding thyroid tissue. Because of the rarity of thyroid fat-containing lesions, confusion in differential diagnosis may occasionally occur. It is important to be aware during frozen section that these lesions may present as extrathyroidal nodules, which can be radioactive on intraoperative scan for parathyroid glands. In addition, a papillary thyroid carcinoma was also identified in one case of thyrolipomatosis. All patients recovered well after surgery and there has been no recurrence of the lesions after 1 to 24 years of clinical follow-up. In summary, we are reporting 5 rare cases of thyrolipoma and thyrolipomatosis with distinct histologic patterns. Previously reported cases of thyrolipomatosis were reviewed and analyzed with the current cases. 相似文献
128.
Doreen Nguyen Diana Taheri Simeon Springer Morgan Cowan Gunes Guner Maria Angelica Mendoza Rodriguez Yuxuan Wang Isaac Kinde Christopher J. VandenBussche Matthew T. Olson Bernardo F. P. Ricardo Isabela Cunha Kazutoshi Fujita Dilek Ertoy Kenneth W. Kinzler Trinity J. Bivalacqua Nickolas Papadopoulos Bert Vogelstein George J. Netto 《Virchows Archiv : an international journal of pathology》2016,469(4):427-434
129.
130.
Induction of immunity at mucosal surfaces is thought to be an essential feature in the protection of the host against the many pathogens that gain access through these surfaces. Here we describe how strong local and systemic immune responses can be generated when proteins are genetically conjugated to pneumolysin (PLY) from Streptococcus pneumoniae. Using green fluorescent protein (eGFP) and PsaA from S. pneumoniae, we have shown that genetic fusion (eGFPPLY and PsaAPLY) is essential to ensure high levels of antigen specific IgG and IgA in the serum and at mucosal surfaces. This form of vaccination is highly effective with antigen specific antibodies detected after a single dose of nanogram quantities of the conjugated proteins. In addition, generation of a non-toxic variant (eGFPΔ6PLY) indicated that while the toxic activity of PLY was not essential for adjuvanticity, it contributed to the magnitude of the response generated. Whilst vaccination with the PsaAPLY fusion proteins did not protect the animals from challenge, these studies confirm the utility of pneumolysin to act as a novel mucosal adjuvant to substantially increase the local and systemic humoral response to genetically fused protein antigens. 相似文献