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OBJECTIVE: To determine frequency of urinary tract infection (UTI) among dogs with pruritic disorders that were or were not receiving long-term glucocorticoid treatment. DESIGN: Observational study. ANIMALS: 127 dogs receiving glucocorticoids for > 6 months and 94 dogs not receiving glucocorticoids. PROCEDURE: Bacterial culture of urine samples was performed in dogs receiving long-term glucocorticoid treatment, and information was collected on drug administered, dosage, frequency of administration, duration of glucocorticoid treatment, and clinical signs of UTI. For dogs not receiving glucocorticoids, a single urine sample was submitted for bacterial culture. RESULTS: Multiple (2 to 6) urine samples were submitted for 70 of the 127 (55%) dogs receiving glucocorticoids; thus, 240 urine samples were analyzed. For 23 of the 127 (18.1%) dogs, results of bacterial culture were positive at least once, but none of the dogs had clinical signs of UTI. Pyuria and bacteriuria (present vs absent) were found to correctly predict results of bacterial culture for 89.9% and 95.8% of the samples, respectively. Type of glycocorticoid, dosage, frequency of administration, and duration of treatment were not associated with frequency of UTI. None of the urine samples from dogs not receiving glucocorticoids yielded bacterial growth. The frequency of UTI was significantly higher for dogs treated with glucocorticoids than for dogs that had not received glucocorticoids. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that dogs receiving long-term glucocorticoid treatment have an increased risk of developing a UTI. On this basis, we recommend that urine samples be submitted for bacterial culture at least yearly for such dogs.  相似文献   
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Simulations are a major tool to evaluate new statistical methods and optimize experimental designs in the genomic era. However, this can only be achieved when the simulations are close enough to reality, as well as diverse enough to be realistic. For mapping studies, it is thus critical to re-create as much as possible the forces generating linkage (mutation, random drift, changes in population sizes, selection and pedigree structure) and the mechanisms producing trait genetic architecture (additivity, dominance, epistasis). We present here a computer program (ldso) simulating these phenomena. Optional outputs provide statistics on the linkage disequilibrium (LD) structure and the identity by descent between chromosomal segments, facilitating further data analyses. Furthermore, ldso enables the simulation of genomic data in known pedigrees, which sticks as precisely as possible to recent population history and structures of the long-range LD, allowing optimization of fine-mapping strategies.  相似文献   
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The anatomy of the neck and forelimb of Chrysochloris asiatica is described and illustrated. The sequence of events during digging and modifications for fossorial action are described. Modifications include the appearance of a third bone in the forearm; the shortening and fusion of bones in the manus; enlarged processes on the scapula, humerus and ulna for greater muscle attachment; enlarged neck muscles and a dip in the spine in the cervical region to accommodate these and the enlarged shoulder muscles; an enlarged occiput for insertion of the powerful neck muscles; a greatly enlarged triceps and movement of the shoulder girdle to a position anterior to that normal in mammals. The possibility of the third forearm bone being the ossified tendon of a flexor muscle is discussed, without any conclusion being reached as to its true origin.  相似文献   
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The following sequence of treatments was administered to a Saint Bernard dog with a primary distal right radius osteosarcoma: 54 days of daily disodium 1-hydroxyethylidenediphosphonate (HEDP) subcutaneous injections; 53 days of HEDP per os ; one 32P-HEDP intravenous injection. During the pretreatment period, there was an extensive increase in calcific tumor growth and osteoblastic proliferation. After the subcutaneous HEDP treatment, almost complete tumor necrosis was seen. After the oral HEDP treatment, only the deepest tumor portion contained active osteoblasts, calcific growth of the tumor was completely blocked, and uptake of 99mTc-Sn-HEDP was reduced to one fourth of the pretreatment uptake. After a single 32P-HEDP dose, large areas of tumor necrosis were evident histopathologically. However, subsequent resumption of cellular activity occurred in the tumor, and the uptake of 99mTc-Sn-HEDP increased to pretreatment values. These data suggest that systemically administered HEDP should be studied further for its possible therapeutic potential in the treatment of osteosarcoma and indicate a need for further study of 32P-HEDP or possibly 33P-HEDP.  相似文献   
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Lomustine for treatment of mast cell tumors in cats: 38 cases (1999-2005)   总被引:1,自引:0,他引:1  
OBJECTIVE: To determine clinical activity and toxic effects of lomustine when used to treat cats with mast cell tumors (MCTs). DESIGN: Retrospective case series. ANIMALS: 38 cats with measurable, histologically or cytologically confirmed MCTs treated with lomustine at a dosage > or = 50 mg/m(2). PROCEDURES: Medical records were reviewed to determine response to treatment and evidence of drug toxicoses. The Kaplan-Meier method was used to estimate remission duration. RESULTS: 26 cats had cutaneous MCTs, 7 had MCTs of the mesenteric lymph nodes, 2 had gastrointestinal tract MCTs, 2 had hepatic MCTs, and 1 had MCTs involving multiple organs. Targeted lomustine dosage was 50 mg/m(2) in 22 cats and 60 mg/m(2) in 16 cats. Median administered dosage of lomustine was 56 mg/m(2) (range, 48 to 65 mg/m(2)), and median number of doses administered was 2 (range, 1 to 12). Seven cats had a complete response and 12 had a partial response, for an overall response rate of 50%. Median response duration was 168 days (range, 25 to 727 days). The most common toxicoses were neutropenia and thrombocytopenia. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that lomustine had activity against MCTs in cats and was well tolerated. Further, findings suggested that treatment with lomustine should be considered for cats with MCTs for which local treatment is not an option.  相似文献   
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An eight-year-old, spayed, female golden retriever was presented with progressive right hindlimb lameness and polyuria/polydipsia. Multiple soft tissue masses were palpable within the hindlimb muscles. A tentative diagnosis of sarcoma was made on fine needle aspiration. A computed tomography scan of the hindlimb and thorax confirmed the presence and location of the masses, none of which were associated with the bones of the hindlimb. In addition, two pulmonary lesions were identified in the right cranial lung lobe. A diagnosis of chondrosarcoma was confirmed on histopathology with a final diagnosis of extraskeletal chondrosarcoma. A high, hindlimb amputation was performed, and chemotherapy was initiated. Polyuria and polydipsia resolved 2 weeks postoperatively. Numerous lung lesions, suspected to be metastases were found on routine followup radiographs, 73 days post surgery after which the dog was lost to follow-up.  相似文献   
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OBJECTIVE: To determine the pharmacokinetics of doxorubicin in sulphur-crested cockatoos, so that its use in clinical studies in birds can be considered. DESIGN: A pharmacokinetic study of doxorubicin, following a single intravenous (i.v.) infusion over 20 min, was performed in four healthy sulphur-crested cockatoos (Cacatua galerita). PROCEDURE: Birds were anaesthetised and both jugular veins were cannulated, one for doxorubicin infusion and the other for blood collection. Doxorubicin hydrochloride (2 mg/kg) in normal saline was infused i.v. over 20 min at a constant rate. Serial blood samples were collected for 96 h after initiation of the infusion. Plasma doxorubicin concentrations were assayed using an HPLC method involving ethyl acetate extraction, reverse-phase chromatography and fluorescence detection. The limit of quantification was 20 ng/mL. Established non-parametric methods were used for the analysis of plasma doxorubicin data. RESULTS: During the infusion the mean +/- SD for the Cmax of doxorubicin was 4037 +/- 2577 ng/mL. Plasma concentrations declined biexponentially immediately after the infusion was ceased. There was considerable intersubject variability in all pharmacokinetic variables. The terminal (beta-phase) half-life was 41.4 +/- 18.5 min, the systemic clearance (CI) was 45.7 +/- 18.0 mL/min/kg, the mean residence time (MRT) was 4.8 +/- 1.4 min, and the volume of distribution at steady state (V(SS)) was 238 +/- 131 mL/kg. The extrapolated area under the curve (AUC(0-infinity)) was 950 +/- 677 ng/mL x h. The reduced metabolite, doxorubicinol, was detected in the plasma of all four parrots but could be quantified in only one bird with the profile suggesting formation rate-limited pharmacokinetics of doxorubicinol. CONCLUSIONS AND CLINICAL RELEVANCE: Doxorubicin infusion in sulphur-crested cockatoos produced mild, transient inappetence. The volume of distribution per kilogram and terminal half-life were considerably smaller, but the clearance per kilogram was similar to or larger than reported in the dog, rat and humans. Traces of doxorubicinol, a metabolite of doxorubicin, were detected in the plasma.  相似文献   
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