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991.
Siegfried Scherer Gerhard Herrmann Joseph Hirschberg Peter Böger 《Current genetics》1991,19(6):503-507
Summary When only plastidic features are considered, it is difficult to distinguish between monophyletic and polyphyletic xenogenous origins of plastids. We suggest that a direct comparison of nuclear and plastidic sequence-similarity pattern will help to solve this problem. The D1 amino acid sequence of six major groups of photosynthetic eukaryotes and of the two groups of photosynthetic prokaryotes are now available, including the psbA-gene product from Bumilleriopsis filiformis, which is the first molecular sequence reported for a xanthophycean alga. Evidence is provided for an independent and polyphyletic origin of plastids from five out of the six major taxa of photosynthetic eukaryotes. This conclusion is reached by comparing a plastid-based pattern of D1 similarity with a nucleus-based similarity pattern published recently. Furthermore, the availability of D1 sequences from five eukaryotic algae led to a re-evaluation of the taxonomic position of Prochlorothrix. 相似文献
992.
The mortality of neonates with oesophageal atresia in the Third World remains high because of delays in presentation and diagnosis. Lack of appropriate intensive care facilities is a further contributing factor. Caudothoracic epidural anaesthesia was used during surgical repair of oesophageal atresia in 35 patients in an attempt to minimise the need for post-operative ventionally support. This group was compared with 36 patients whose surgery was performed under general anaesthesia. The age at the time of referral, sex ratio, and weight were comparable in both groups. Using the Waterson classification, a greater number of poorer prognostic patients were seen in the epidural group (P <0.02). In all Waterson risk categories fewer patients required ventionally support post-operatively, which was statistically significant (P <0.01) when all categories were combined. We are encouraged by our results and believe this technique has a rôle in the management of neonates undergoing major surgery, both where neonatal intensive care exist or is deficient as in many parts of the Third World. 相似文献
993.
Lupus vulgaris in a patient with systemic lupus erythematosus and persistent IgG deficiency 总被引:2,自引:0,他引:2
N. Düzgün M. Duman B. Sonel Y. Peksari C. Erdem G. Tokgöz 《Rheumatology international》1997,16(5):213-216
We present the case of a patient with juvenile onset systemic lupus erythematosus (SLE) who developed a persistent, acquired hypogammaglobulinaemia with IgG deficiency. The hypogammaglobulinaemia was probably a complication of high dose corticosteroid treatment. The serum IgG level remained subnormal despite intravenous immunoglobulin therapy. Lupus vulgaris, which developed on the nasal cartilage in this patient with SLE, is not an expected finding. This patient is probably the first reported case of SLE associated with lupus vulgaris. 相似文献
994.
995.
996.
Age, hematopoietic growth factors, cyclosporin A, mode of bone marrow transplantation (BMT) (autologous, allogeneic-related,
unrelated), and underlying disease were assessed as potential risk factors for capillary leakage syndrome (CLS) in 96 patients
after BMT. CLS was defined as unexplained weight gain of >3% within 24 h and nonresponsiveness to furosemide. CLS occurred
in 9/21 patients after unrelated compared with 2/33 after allogeneic-related BMT (p=0.0017) for hematopoietic disorders (n=54) and in 6/7 patients after allogeneic-related compared with 3/35 after autologous BMT (p=0.0001) for solid tumors (n=42). Hematopoietic growth factors and cyclosporin A were no signficant risk factors on their own. We conclude that unrelated
BMTs or high-intensity conditioning regimens used in combination with allogeneic-related BMT are the main risk factors for
CLS.
Received: 6 January 1997 / Accepted: 10 March 1997 相似文献
997.
998.
A. Böcking 《Der Pathologe》1998,19(1):53-58
Zusammenfassung
Die transrektale, palpatorisch kontrollierte FNAB der Prostata ist eine preiswerte und schnelle Methode zur Diagnostik palpabler
und nichpalpabler Raumforderungen mit hoher Sensitivit?t (ca. 95%) und niedriger Komplikationsrate ( <1%). Ihre Spezifit?t
betr?gt >97%. Der Mangel an geübten Punkteuren und zytologisch erfahrenen Pathologen schr?nkt jedoch bisher die klinische
Anwendung der Methode ein. Neben diversen Formen der Prostatis k?nnen 5 verschiedene Prim?rtumortypen differenziert werden.
W?hrend PIN I zytologisch nicht diagnostizierbar ist, mu? man bei PIN-II/III-L?sionen mit falsch-positiven zytologischen Karzinomdiagnosen
rechnen. Das zytologische Malignit?tsgrading ist prognostisch relevant und eng mit dem histologischen korreliert. Die pr?operative,
radiologisch kontrollierte FNAB pelviner und paraaortaler Lymphknoten tr?gt mit einer Sensitivit?t von ca. 86% und einer Spezifit?t
von ca. 100% zur Vermeidung wegen Lymphknotenmetastasierung nicht indizierter Prostatektomien bei.
Die diagnostische DNA-Zytometrie erkennt in den konstant und repr?sentativ diploiden und tetraploiden Prostatakarzinomen diejenigen,
welche nicht nur ein sehr geringes Progressionsrisiko aufweisen, sondern die auch unbehandelt gegenüber gleichalten gesunden
Patienten kein erh?htes Sterberisiko mit sich bringen. DNA-tetraploide Prostatakarzinome zeigen unter Hormontherapie wahrscheinlich
eine Verschlechterung der Prognose. DNA-aneuploide Prostatakarzinome dürfen nicht abwartend therapiert werden; sie sprechen
auch auf eine Hormontherapie nicht an.
相似文献
999.
1000.
Viktoria Werkström Lars Ny Katarina Persson K.-E. Andersson 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(2):151-158
Neuronal regulation of smooth muscle tone in the female pig urethra has mainly been studied in vitro using electrical field
stimulation (EFS) of nerves. Excitatory control is considered to be exerted by released noradrenaline, whereas inhibitory
control is non-adrenergic non-cholinergic (NANC), and mediated by nitric oxide (NO), and an as yet unidentified agent. We
investigated the functional and morphological effects of α-latrotoxin (αLTX), a spider neurotoxin believed to cause massive
release of vesicle-stored neurotransmitters, on spontaneously developed urethral smooth muscle tone. The effects were compared
to those of EFS and high potassium. In the presence of the NO-synthesis inhibitor Nω-nitro-L-arginine (L-NOARG: 0.3 mM) both αLTX and EFS evoked contractions. After treatment with scopolamine and phentolamine,
no contraction was observed, and under these conditions αLTX and EFS induced relaxation. At low frequencies (<12 Hz), the
EFS-induced relaxations were rapid, whereas at higher frequencies (>12 Hz), they were biphasic, consisting of a rapid first
phase followed by a more long-lasting second phase. L-NOARG abolished the relaxations at low frequencies, as well as the first
phase of the biphasic relaxation. The second phase was not affected by treatment with L-NOARG, but 0.1 μM ω-conotoxin GVIA,
blocker of N-type voltage-operated calcium- channels (VOCCs), markedly reduced or abolished the response. In the presence
of L-NOARG or ω-conotoxin GVIA, the αLTX-induced relaxation was significantly decreased, and the combination of L-NOARG and
ω-conotoxin GVIA further reduced or abolished the relaxation. In preparationstreated with tetrodotoxin or scorpion venom,
believed to inactivate nerves by acting on sodium channels, αLTX and EFS had no effects. αLTX-induced relaxation was not associated
with changes in cyclic GMP or cyclic AMP content. High (80 mM) potassium solution induced a triphasic response of the preparation.
A transient relaxation was followed by a restoration of tone, and then by a persistent relaxation. The persistent relaxation
was slightly reduced by scorpion venom or L-NOARG, but reduced by 50% by a combination of L-NOARG and ω-conotoxin GVIA. Ultrastructural
analysis of the urethral circular smooth muscle layer revealed a moderate amount of nerve profiles supplying the smooth muscle.
In control preparations, the nerve profiles contained both small synaptic vesicles and large dense core vesicles. αLTX caused
a major loss of both types of vesicle. The present data suggest that αLTX has the ability to release not only adrenergic and
cholinergic transmitters, but also NANC mediators of relaxation, including NO, from nerve terminals in the urethra.
Received: 13 January 1997 / Accepted: 17 April 1997 相似文献